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What We Know About Black Storks

Posted: August 9th, 2019, 4:14 pm
by Jo UK
What We Know About Black Storks.

For example -

solo p. 280

(see P 266)
Contributed by Anne7
In 2016, Urmas wrote:
"Chicks age at first flights depends on food abundance in previous stages in development. If we go back in years 2007-2011 then we see difference of first flight in weeks in the same nest. There may be different parents, but for sure the years are different for availability of food by parents. Our storklets were well fed by ringing time. According our Latvian colleague Maris Strazds better results are in surviving of the chicks which spend longer time in nest after fledging, means they return to the nest and step by step get independent, but are still getting food from parents in nest. Disturbance, what leads flying off the nest is negative for further survival. Therefore we are very much cautious in visiting the nests at late stage of breeding. Lets hope Karl will follow that hint to spread his genes firmly... Absence of Kati is not good in that context, though." ... 21#p488921
Concerning the known diet of nestling black storks see posts by Solo, Liz, Anne on p.274

Re: What We Know About Black Storks

Posted: August 9th, 2019, 4:19 pm
by Jo UK

Re: What We Know About Black Storks

Posted: August 9th, 2019, 4:19 pm
by Jo UK

Re: What We Know About Black Storks

Posted: August 9th, 2019, 4:20 pm
by Anne7
T A B L E . O F . C O N T E N T S
Please click on the link to jump directly to the chapter.


Black Storks in Estonia

Information on Black Storks in general

Habitat Analysis for the breeding Black Stork - Forest management and conservation planning

Black Stork Courtship Displays and Territories

Reproduction, Eggs and Brooding

Brood Reduction and Parental Infanticide among Black Storks

Black Stork Nestlings - Diet, gender ratio, body condition...

Depredation of Black Stork Nestlings and Eggs

Flight, Feathers and Moult

viewtopic.php?p=687664#p687664 PART 1. Different Routes
viewtopic.php?p=687682#p687682 PART 2. Stopover Places
viewtopic.php?p=687686#p687686 PART 3. The influence of the Weather
viewtopic.php?p=687712#p687712 PART 4. Migration of the Black Stork
viewtopic.php?p=687720#p687720 PART 5. Dangers during migration

Wintering Black Storks

Status of the black stork (Ciconia nigra) in countries other than Estonia

Parasites and diseases in the Black Stork - Avian medicine and microbiology

The family Ciconiidae


Bird anatomy
viewtopic.php?p=687819#p687819 PART 1. Skeletal system
viewtopic.php?p=687776#p687776 PART 2. Muscular system
viewtopic.php?p=687823#p687823 PART 3. Integumentary system
viewtopic.php?p=687846#p687846 PART 4. Respiratory and circulatory system
viewtopic.php?p=688469#p688469 PART 5. Digestive system
viewtopic.php?p=688474#p688474 PART 6. Reproductive and urogenital systems
viewtopic.php?p=688495#p688495 PART 7. Nervous system
viewtopic.php?p=688495#p688495 PART 8. Immune system

Wings, Flight and Feathers

Bird vocalization

Research into Bird Migration

Bird intelligence

Bird Senses
viewtopic.php?p=690352#p690352 In general
viewtopic.php?p=690352#p690352 PART 1. Smell (olfaction)
viewtopic.php?p=690366#p690366 PART 1. The role of olfaction in avian navigation
viewtopic.php?p=690371#p690371 PART 2. Sight (vision)
viewtopic.php?p=690382#p690382 PART 3. Hearing
viewtopic.php?p=690669#p690669 PART 4. Touch (tactition)
viewtopic.php?p=690689#p690689 PART 5. Taste


VII International Conference on Black Stork Ciconia nigra
viewtopic.php?p=690851#p690851 PART 1. Black Stork Population and Trends
viewtopic.php?p=690852#p690852 PART 2. Threats and Conservation of Black Stork
viewtopic.php?p=690853#p690853 PART 3. Ecology and Behaviour of Black Stork
viewtopic.php?p=690855#p690855 PART 4. Movements, Tracking, Ringing & Migration of Black Stork

Re: What We Know About Black Storks

Posted: August 9th, 2019, 11:49 pm
by Anne7
Black Storks in Estonia


Eagles and Black Storks in Estonia
Text: Fred Jüssi, Tiit Randla, Urmas Sellis, Ülo Väli
Every year, those checking the nests of this ”bird of the underworld”, the Black Stork, are faced with a disturbing sight at several of the nests – nestlings have starved to death before fully fledging. What can we do to help this species which is vanishing from this area? Is it enough to fill a fridge with small fish for the stork nestlings, carrying it in the back of the field worker’s car? Obviously, this tactic hasn’t been used and surely it would seem mysterious to the adult storks who don’t want to see people around their nest site. Evolution up to this time has led the Black Storks ever further from areas of human inhabitation. Could this adaptation, which through the past has been the key to its survival, now have negative effects? Or is it possible that the species can change its millennia-old behaviour in response to new conditions?
The Black Stork is rather widely distributed in the temperate zone of Eurasia, to the east and south of Estonia. This area, however, is covered very sparsely. The Black Stork more or less disappeared from Western and Central Europe over the past two- to three hundred years, mostly as a result of ever-diminishing forest cover and intensive land melioration activities, as well as with the uncontrollable use of chemical pesticides in the middle of the last century. The Baltic States, Poland, Belorussia and probably also western Russia remained more natural and cleaner as a result of climatic as well as political influences. The population, which remained stable in these parts, migrated to Africa, flying over areas that they had previously inhabited. So it is not so unusual that after the improvement of conditions there, some pairs of Black Storks again reoccupied western European nesting sites. Improved natural conditions and a positive attitude help provide a new chance for numbers in those areas to increase. ... ... chure1.pdf

The Black Stork in Estonia
The Black Stork is shy and beautiful bird, living as far from human settlements as possible. Black Storks forage along small streams in forest, on fishponds and on flood plains as well. For nesting they use huge trees with healthy branches, mainly in wide forested areas. In Estonia, we can find breeding about 80 pairs of Black Stork. Several specimens are tagged with transmitters and let us know about their behaviour and migration.
In Eastern Europe their numbers have greatly declined over the past thirty years, most likely due to land improvement (melioration) and the diminishing supply of suitable old forests for nesting.

Karula National Park
Environmental Board of Estonia
The smallest (surface area: 123 km2) and hilliest national park in Estonia, Karula National Park is located in the Karula Uplands, on the borders of Valga and Võru counties. The varied terrain of Karula was placed under national protection, with the original landscape protection area being designated a national park in 1993.
The park was established to preserve the natural environment found in the hilly landscapes characteristic of Southern Estonia, where forests and lakes abound, as well as species under the protection and the cultural heritage of the area. Karula National Park belongs to the Natura 2000 network of protected areas in the European Union.
The unique, beautiful terrain of the Karula Uplands formed more than 10,000 years ago as a result of the action of glacial ice. With the continental glacier retreating, the northern section of Karula came to feature predominantly dome-shaped kames, or hills covered with elds, grassland or forests. Kames are separated from one another by small, wet meadows, forest stands, patches of marshy ground and lakes. The hilly section of the national park is its most densely populated area. The southern part of Karula features groups of eskers and kames with mires and forests, where human settlements are quite rare. The highest point in the uplands is Tornimägi Hill (137.8 m) in the village of Rebasemõisa. The uplands between the Valga Depression and the Võru-Hargla Valley zone also function as a watershed area between Lake Peipus and the Gulf of Riga. The brooks and rivers which originate from the uplands are small and carry little water in their upper reaches. The best-known river here is the Mustjõgi, which flows from Lake Suur Saarjärv. ... ula_EN.pdf

The observed Black Stork nest in Karula National Park
This Black Stork nest is located in Karula National Park which is probably the best breeding area for Black Stork in Estonia nowadays. It was found in February 2016 by Eagle Club nest searching camp.

The old nest, on the right, collapsed after the breeding season 2017.
On the left, the new, artificial nest, build by Urmas & Friends, before the breeding season 2018.


Overview of the chicks raised in the observed nest in Karula National Park
2016 - 2018: Karl & Kati
2019: Karl II & Kati


Posted here viewtopic.php?p=620587#p620587
Feeding habits
Kotkaklubi website
The main food of the black stork includes all kinds of fish and amphibians that it prefers to catch from small forest rivers and ditches. On rarer occasions, the black stork can be seen feeding from lakes, fish ponds, shallow seawater, and meadows. Research in recent years indicates that male birds can fly distances of up to 25 km from the nest to reach good feeding grounds.

Posted here viewtopic.php?p=671270#p671270
Food items seen at the Karula nest
In 2018, we have seen these food items at the Karula nest:
- fish: pike, common roach, perch, trout, lamprey, eel, stickleback ...
- amphibians: different species of frogs, salamanders...
- reptiles: common adder, lizard (Kati)
- decapods: Astacus astacus (Kati)
- mammals: rodents (young muskrats? short-tailed vole?) (Kati)
- birds: chicks (from waterfowl?) (Kati)
- worms: earthworms, leeches
- (water)beetles, ... (Kati)
Kati brings mostly frogs, sometimes fish and other food.
She brought a much more extensive range of food items than both Karls.
Karl I (and in 2019, also Karl II) brought mostly fish, sometimes frogs.
This list is certainly not exhaustive.

Systematic list of Estonian amphibians
Salamanders, Newts, Salamandridae:
1. Crested Newt, Triturus cristatus Laurenti
2. Smooth Newt, Triturus vulgaris L.
Foot Toads, Pelobatidae:
3. Spade Foot Toad, Pelobates fuscus Laurenti
Toads, Bufonidae:
4. Common Toad, Bufo bufo L.
5. Green Toad, Bufo viridis Laurenti
6. Natterjack Toad, Bufo calamita Laurenti
Frogs, Ranidae:
7. Common Frog, Rana temporaria L.
8. Moor Frog, Rana arvalis L.
9. Pond Frog, Rana lessonae
10. Lake Frog, Rana ridibunda Pallas
11. Water Frog, Rana esculenta

Posted here viewtopic.php?p=589045#p589045
Systematic list of Estonian reptiles
A. Lacertidae
1. Common Lizard, Lacerta vivipara Jacquin
2. Sand Lizard, Lacerta agilis L.
B. Anguidae
3. Slow Worm, Anguis fragilis L. (a legless lizard)
C. Colubridae
4. Grass Snake, Natrix natrix (L.)
D. Viperidae
5. Adder, Vipera berus (L.)

Posted here: viewtopic.php?p=610918#p610918
List of Freshwater Fishes for Estonia
Number of freshwater fish species: 60

Foraging habitats of the black stork in Estonia
Asko Lõhmus and Urmas Sellis
According to casual observations in the 1990s, the main foraging habitats of the Black Stork (Ciconia nigra) in Estonia were waterbodies (87,8% of the total of 82 foraging sites), especially rivers, streams and ditches (63,4% of sites). The sites were often situated near roads and even farms, but were usually shaded by forest cover. The Storks foraged on average 3.6+0.8 km (range 0.7-5.9 km) from known nests, but this value is likely an underestimate. Lowered quality of foraging habitats due to forest drainage may be one of the reasons for the decrease of the species in Estonia. ... in_Estonia

Articles on the Black Stork population in Estonia

Will the Black Stork remain to breed in Estonia?
Urmas Sellis
The Black Stork (Ciconia nigra) is at the north-western border of its distribution range in Estonia. The paper summarises data on its numbers and distribution in Estonia in 1999, reproductive success in 1991-1999, and results of the special Bird of the Year project in 1998. The latter, which was aimed at rising public awareness and gathering additional data, resulted in three new nests. sites and a total of 62 territories counted. The main result, however, was propagation success - in public opinion the Black Stork was among the most well known protected species in 1999.
The numbers were estimated at 100-120 pairs in 1999, which is 2-2.5 times less than two decades ago (see Renno 1993, Ldhmus et al. 1998). Distribution concentrated into the largest forest areas rich in rivers and streams (Fig. 1). The population decline coincided with low productivity in the last decade, on the average 1.09 young per occupied (at least some nest-building activity registered) nest and 44% of nest sites successful (Table 1).
Trends in all reproductive criteria were negative (although not statistically significant), except the number of dead young in nests, which was highest in the years of summer droughts (1994-1997; Fig. 2). Most probably the reasons of decline and poor reproduction are in our breeding grounds, because some other populations that use the same migration route and wintering areas are increasing. Productivity in the neighbouring countries is as poor as here (Fig. 3), thus, there is no potential for immigration. Characteristically to declining population, the reproductive rates in Estonia fluctuated widely between years. Therefore, it is important to monitor the population every year. However, in the 1990s state monitoring program covered the Black Stork only in 1994 and 1999, which are not representative, as these happened to be the best years for breeding (Table 1).
In general, the status of the Black Stork in Europe is alarming. Decreases in the previous source-populations of Poland and the Baltic States are not compensated by increases in other, much smaller populations (Strazds et al. 1995). For conservation, it is important to find out the reasons for declines, which probably will be successful only by international cooperation.
The study and (especially) conservation of the Black Stork in Estonia is carried out by two closely co-operating NGOs, the Eagle Club and the Nature Conservation Society "Kotkas".
Legally, the Black Stork is included in the strictest conservation category (I) and the state, represented by the Ministry of the Environment, is responsible for organising the conservation. Probably, the national management plan for the Black Stork will be compiled in 2000. ... Kws3qXFUKX ... -4_205.pdf

Contributed by Ari19
Nest trees - a limiting factor for the Black Stork (Ciconia nigra) population in Estonia
ABSTRACT - To assess the role of nest trees as a limiting factor for the Black Stork population in Estonia, we have described 49 nest sites and have explored the availability of potential nest trees in randomly selected plots. Compared with the composition of neighbouring nest stands, the storks strongly preferred to nest on oaks and aspens, followed by pine, and avoided spruce. Our analysis shows that the disproportional use of tree species could be explained by their canopy structure, notably the opportunity to hold a large nest away from the main trunk. On average, the nest trees were 25.6 m high, 120 years old and had a 66-cm diameter at breast height. Different tree species became suitable at different ages. Similarly to the other Baltic countries, nest trees were older than nest stands, showing that older tree retention during forest management practices is important for the species. In a random landscape, 3.5% of forest land contained at least one tree suitable for nest building, but after considering also stand structure and location, only 0.3% of forest land could be listed as suitable. We conclude that the shortage of potential nest trees is severe enough to limit the Estonian Black Stork population, and that sylvicultural management for retaining or creating such trees in forested areas are by far under-used. ... 1-4_84.pdf

Have recent changes in forest structure reduced the Estonian black stork Ciconia nigra population?
Asko Lõhmus, Urmas Sellis, Raul Rosenvald
Abstract: The black stork Ciconia nigra is listed as a focal species for guiding forest management in Estonia, where forestry has recently intensified and the stork population has suffered a twofold decline. We explored a possible link between the decline of the population and man-induced changes in forest structure, by analysing nesting of the species in relation to forest cover, edge effects and stand structure. Although the storks had distinct habitat preferences (old remote stands near rivers and a certain distance far from ecotones in well-forested landscapes), these were hardly reflected in site re-occupancy and productivity. Therefore, changes in forest structure are probably not responsible for the population decline, although preferences for specific forest environments may limit the range of potential nest sites. The results indicated that edge avoidance cannot be considered a species-specific feature over large areas and clear habitat preferences are not necessarily related with the present success of a population. We also suggest that lists of focal species should be regularly updated and validated in the field. ... 004-9667-5

Solitude at periphery:
lack of partners limits reproduction of the Black Stork (Ciconia nigra) at the margin of the distribution range

Annika Konovalov, Rein Nellis, Renno Nellis, Ain Nurmla, Urmas Sellis & Ülo Väli
Abstract: Understanding the mechanisms forming species’ ranges is a central ecological question, which could be answered by analysing factors limiting peripheral populations. In threatened species, such studies are essential for establishing effective conservation measures across the range. We analysed factors potentially influencing breeding in a declining peripheral population of a long-lived bird, the Black Stork (Ciconia nigra). We assessed reproductive success and the effects of intra- and interspecific competition, as well as predation by recording events at nests by remote cameras (camera traps and a webcam). The productivity of storks was low (1.1 fledgelings per occupied nest) compared to the other parts of the range and resulted mainly from the lower proportion of successful nests (37% of occupied nests). The main reason for low breeding success was the occupancy of many nests (35%) by single non-reproductive birds. Breeders were often visited by non-local conspecifics, which harassed local birds but only seldomly caused direct damage. Impact of predators and interspecific nest-competitors on reproductive success was low. We suggest that many individuals have disappeared from the breeding population and shortage of mates is currently the most important factor lowering the reproductive success of the Black Stork at its northern range margin. This mechanism could also limit the peripheral abundance and distribution in other long-lived birds.

The black storks in Estonia are suffering from loneliness
In Estonia, the rare Black Stork are living on the northernmost edge of their distribution range. In recent decades, the population of the species has significantly declined; however, no unequivocal reason to it has been found. At the same time, the breeding success of the Black Stork in Estonia is much lower than in the rest of Europe, including Latvia and Lithuania.
A recently completed research by Estonian University of Life Sciences, NGO Eagle Club and Estonian Environment Agency tried to find out the factors impacting the low breeding success of the Black Stork that has led to the decline of its Estonian population. In the course of six years, automated cameras were installed close to the nests of the Black Stork all over Estonia in order to record events in the nest. Each year, up to twenty cameras were installed and a total of nearly 450 000 photos were analysed.
At first, the effect of predation on the breeding success was analysed, as the European pine marten was previously considered the main predator. However, the impact of predatory animals proved very low. As a surprise, it came out that one third of the nests of the Black Stork in Estonia are inhabited by single birds who cannot breed due to lack of partner. Such single birds may leave their nests and annoy breeding couples. Thus, the Black Stork in Estonia lack partners who may have died on long migration routes or proceeded to breed elsewhere where living conditions are more favourable than here. On the one side, the results of the research help clarify the ecology of factors shaping the species' range; on the other hand, they enable to pinpoint how to plan further steps for the protection of the species. ... 020619.php

Contributed by Biker
Extremely Sad Birds Show How a Population Can Die From Loneliness
"Waiting for a partner. Often in vain."

Black storks in Estonia are experiencing a situation all single people have lived through: Taking stock of your life and realizing that you’re completely, utterly alone. Unlike lonely millennials, these monogamous birds don’t have the option of swiping right for a last-ditch hookup, which is deeply unfortunate. As new research on this threatened species indicates, it could be possible for an entire population to die from loneliness.
Bird watchers in Estonia had noticed for years that some populations of the elegant black storks, with their spindly red legs and pointed beaks, have been declining for a long time, but nobody was sure whether it was predators, changing climate, or another factor altogether. ... ... you-and-me

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Re: What We Know About Black Storks

Posted: August 10th, 2019, 11:47 am
by Anne7
Information on Black Storks in general

Black stork
From Wikipedia, the free encyclopedia

Contributed by Bea
Stork, Ibis and Spoonbill Specialist Group
Historical literature

Der Schwarzstorch (BOOK in German)
Gerd Janssen, Martin Hormann, Carsten Rohde
Neue Brehm Bücherei, 2004

La Cigogne noire (BOOK in French)
Gérard Jadoul
Éditions du Perron, 1997

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Re: What We Know About Black Storks

Posted: August 12th, 2019, 12:47 am
by Anne7
Habitat Analysis for the breeding Black Stork.
Forest management and conservation planning

Posted here: viewtopic.php?p=545852#p545852
Breeding and migration of the Black Stork (Ciconia nigra), with special regard to a Central European population and the impact of hydro-meteorological factors and wetland status
Tamás Enikő Anna
Doctoral (PhD) thesis, 2012

People have been altering the Earth‘s surface for thousands of years. Land use and cover changes, caused by increasing human habitation coupled with resource consumption and extensive landscape modification, adversely impact natural ecosystems at multiple spatial scales. Habitat loss has induced increased extinction risks for rare and highly specialised species, and particularly to migratory birds, as migratory birds and species with specific habitat requirements are considered to be the most sensitive to anthropogenic disturbances. ... sAllowed=y

Habitat Preferences of Black Stork Nesting
SPC of NAS of Belarus for Biological Resources Minsk, Belarus

Studies of Black Stork Ciconia nigra habitat preferences are important to actualize the legislation on protection of Black Stork. Additionally, it is useful to select sites for building artificial platforms for Black Stork. In 2016-2017 we conducted a description of a number of characteristics of forest and other factors.
We studied habitat preferences between real Black Stork nesting places and random places (theoretically good for nesting) in forest environments, used as a control group. The study was conducted in Belorussian Polesie (Brest region) on 3 plots: Middle Pripyat (Stolin district, anthropogenic pressure is low, old forest, plot area is 95 km2, monitoring plot with all nests known), L'va (Stolin district, human activity exists, less old forest, plot area is 240 km2, monitoring plot with all nests known), Belovezhskaya Pushcha (Kamenec district, anthropogenic pressure is just absent, some of nests are known). Broadleaf and small-leafed swampy forests are dominating in Middle Pripyat and Belovezhskaya Pushcha and on L'va plot pine forests are dominating.
All 3 plots are different in tree density and age. Meanwhile, Black Stork habitat does not differ between plots significantly. Thus we can identify optimal habitat conditions for Black Stork nesting, which are same in all plots. Optimal density was 29.89 ind/500 m2 (±11.04) (N=148), tree diameter varies from 21.85 mm (±13.68) in L'va plot (N=633) to 24.68 mm (±15.14) in Belovezhskaya Pushcha (N=747). Projective cover ratio of bushes was 20.06 % (±20%), 38.96% in control (±34%). The role of bushes is mixed. They hide nests from predators, but in some cases, if Black Stork nest is very low, it can prevent Black Storks to visit their nest. ... t-Book.pdf

An analysis of nesting data of Black Storks Ciconia nigra in the Gemenc region of the Danube-Drava National Park (1992-2003)
Béla KALOCSA & Enikő Anna TAMÁS
Abstract: Between 1992 and 2003 we registered 189 Black Stork nests in the Gemenc area. We cooperate with the regional Nature Protection Authority, and give them our data so that they can carry out legal protective measures. For the surroundings of the registered nests, we analyzed the available data. From our studies, we concluded that the forest type chosen for nesting proved to be the most significant factor, and forestry proved to be the biggest threat to nesting. Breeding success and other factors influencing the Black Stork population have also been investigated for 12 years. ... 2-2003.pdf

Conservation Ecology of the Black Stork in Latvia
Dissertation for a PhD in Biology, Zoology. 2011
Māris Strazds
The black stork is a unique species in many ways. It has the most extensive breeding range of any species of storks (Hancock et al. 1992), as well as one of the widest distribution ranges among all bird species – the black stork has been recorded in more than 105 different countries (Strazds 1995). At the same time the black stork is not common in any country. At the regional level, it has been considered to be threatened in most of its range countries (Hancock et al. 1992). When Luthin (1987) was analysing the status of the world’s species of storks and the conservation priorities in this regard, he categorised the black stork as being globally vulnerable. Despite this, the bird has never been listed on any official list of globally threatened species. The main reason for this is the huge range which the bird covers, even though the overall size of the population only slightly exceeds the “small population” criterion (fewer than 10,000 mature individuals) of the IUCN/SSC (BirdLife International 2000). In Europe, the black stork is classified as rare, and it has been assigned the conservation priority rank of SPEC2 (BirdLife International 2004). ...

Black Stork is not only a bird... (In French) 2003
Philippe COLLAS
Summary: It's not a secret anymore, the Black Stork has been breeding again in Belgium for fifteen years. Incontestably, this return was a major event in the world of Belgian ornithology, but was also an occasion that the RNOB (Réserves Naturelles et Ornithologiques de Belgique) association couldn't miss.
Worried about a constant loss of wetlands, the richest ecosystems of the Ardennes (south-east Belgium), and aware of the need to react quickly to preserve what was left (2/3 of wetlands have already disappeared in less than a century), this association started in 1989, with the help of "Hëllef fir d'Natur" of Luxembourg, a program centred on Black Storks.
Although the primary goal of this project wasn't the protection of the species, but the conservation of its feeding areas, and consequently of the biodiversity of those wetlands, the Black Stork was chosen to be the symbol of this project.
This species was clearly fit to be a symbol because it frequents wetlands to forage for food, it was back after a long absence unlike other threatened species, and finally, it is well known to a wide public.
After more than 10 years, this project allowed the creation of 37 natural reserves covering a surface of 355 hectares. Those sites, now preserved from drainage, spruce plantation, filling in..., are situated in Fauvillers, Vaux-sur-Sûre, Léglise, Bertogne, Bastogne, Houffalize, Gouvy, Vielsalm, and Burg-Reuland.
Acquisition of those plots was made possible through the financial help of the Région Wallonne, the European Community and private sponsorship. Most purchases were done before 1995 (end of European financing), but since then, 10 to 20 hectares are bought annually among those districts. ... -4_207.pdf

Applying Objective Data for a Multi Temporal Analysis of Habitat Suitability Indices to Monitor Biodiversity - A Case Study for the Example Key Species Red Kite (Milvus milvus) and Black Stork (Ciconia nigra)
Bernhard Kenter
The study describes the potential of various habitat suitability indices (HSI) using remotely sensed data (Landsat 5 and 7) and other mapped information in digital format for the characterization and monitoring of rare species habitats at the landscape level over time. The main focus was to develop a flexible and open system for habitat monitoring which allows a pragmatic overview of habitat development without field assessments, or with very limited field assessments. The potential HSI models for the exemplary key species Red Kite (Milvus milvus) and Black Stork (Ciconia nigra) are analysed with regard to their sensitivity to changing environmental conditions, and also with regard to the influences of individual attributes used as input for the models. The Moritzburg area located close to the city of Dresden, Germany was selected as the study site. It is characterised by a pronounced heterogeneity of landscape elements such as forests, meadows and lakes. The remote sensing data for the year 2000 were combined with ground data collected in the field campaign of the EU research project “MNTFR”. In addition, the database “Datenspeicher Wald” provided forest information for the year 1989 based on the forest inventories at the company level. Attributes, based on Natura 2000, such as food supply or nesting resources, were utilised as input for HSI models. The in situ data were combined with satellite data using a spatial statistic approach called kNN method for extending in situ attributes to the entire area of interest. Habitat suitability maps for both occasions (1989 and 2000) were compared for the individual key species. The methods described underlay the three HSI models tested in this study: a) The Habitat Suitability Index (HSI) with binary attribute maps, b) The Enhanced Habitat Suitability Index (EHSI) applying binary attribute maps enhanced with fuzzy sets and c) The Habitat Suitability Index with Home Rage Aspect (HR-HSI) applying recalculated attribute maps with an activity radius of 200 m for each pixel. Each of these HSI models includes two levels of consideration: the attribute level and the life requisite level. The multiplicative approach with multiplicative combination of life requisites resulted in the original models HSI, the EHSI and HR-HSI and the summation approach with additive recombination of life requisites resulted in the models HSI+, EHSI+ and the HR-HSI+. While all six HSI models are able to detect habitat changes and to predict future habitat development, the EHSI model proved to be efficient to enhance purely binary data into discrete transition probabilities along suitable pixel with a decreasing probability within a distance of 150 m. The HR-HSI model proved to be useful in describing neighbourhood relations of habitat attributes. It offers a graduation of habitat potentials calculating continuous transition probabilities. The HR-HSI model is sensitive for areas of minimum 25 hectares indicating potential habitat loss or gain in the test site. The model approaches can support decision- and policy-making concerning landscape management, as well as enabling simulation of changing individual attributes.
The main obstacle to a successive implementation of the HSI models is a comprehensive description of factors driving habitat suitability that have hardly been presented in quantitative terms. Therefore an interdisciplinary knowledge transfer is recommended to realise the implementation of quantitative information of species specific requirements. ... online.pdf

The Impact of Different Management Scenarios on the Availability of Potential Forest Habitats for Wildlife on a Landscape Level: The Case of the Black Stork Ciconia nigra
Jan Banaś, Stanisław Zięba, Małgorzata Bujoczek and Leszek Bujoczek
Abstract: This study analyzed the effects of various forest management scenarios on habitats of the black stork, which has very specific requirements: it needs extensive forest complexes with a significant proportion of old trees for nesting, and bodies of water for foraging. The relationship between different forest management scenarios and the presence of black storks was examined in a large forest complex (9641 ha of managed stands) surrounded by wetland areas. A simulation of forest development under three management regimes was performed for eighteen 10-year periods. Management scenarios differed in terms of the species composition of stands, rotation age, retention tree areas, and silvicultural treatments. The basic scenario was characterized by a species composition consistent with natural-type stands, but with higher proportions of Scots pine and oak, with rotation ages of 100 and 140 years, respectively, managed by the shelterwood system. The productive scenario featured monospecific stands with a dominance of Scots pine with a rotation age of 90 years, harvested by clearcutting. Finally, the long rotation scenario introduced mixed tree stands with a long rotation age (110 and 180 years for Scots pine and oak, respectively). As compared to the basic scenario, the total harvest volume was greater by 14.6% in the productive scenario and smaller by 16.2% in the long rotation scenario. The availability of habitats for black stork changed as a result of different species compositions and age structures of tree stands. A considerable decrease in rotation age (below 100 years) and the elimination of oak trees from stands in the productive scenario adversely affected potential habitats for black stork. On the other hand, the factors favorable to black stork habitats were a long rotation age, the presence of oak in stands, the application of shelterwood cutting, and the use of retention trees in the long rotation scenario. This scenario would probably also benefit other bird species legally protected under the European Union’s Birds Directive.

Posted here: viewtopic.php?p=612979#p612979
Bokotey A., Strus Iu., Dzubenko N.
The study was based on an overlay analysis in GIS. Exact locations of 108 nest and layers representing forest types, prevailing tree species, forest age and productivity (bonitet class) were used. The analysis was performed on the level of individual nests (spatial join to point layer), and on the level of buffers with 500m radius around nests. To find the most preferable forest types for Black Stork we compared the frequency of distribution of forest types on the nesting territories with the frequency of distribution of those types in the study area and in 500m buffers around 108 random points. According to the results of our research, the spatial distribution of Black Stork nests to a great extant follows the general structure of forests in the region. We found some selectivity in case of wet forest types with prevalence of oak with pine, as well as with black alder, but the result is not statistically significant. The only statistically significant relation was found in case of forest age. Black Storks prefer old and mature forests. The most important trees for nesting were oak (53,3%) and pine (29,9%). ... view-paper

Nest-site use by Black Stork and Lesser Spotted Eagle in relation to fragmented forest cover: case study from Lithuania
Rimgaudas Treinys, Saulis Skuja, Danas Augutis, Darius Stončius
Black Stork and Lesser Spotted Eagle are forest-dwelling species that nest in mature forests, thus are in conflict with the timber harvesting. No recent research has evaluated the demand for continuous forest cover around nest-trees of these species. is article analyses nest-site use by Black Stork and Lesser Spotted Eagle in relation to ground cover, specifically comparing the nest-tree environment with availabilities in the forest landscape. Strong avoidance of field, low avoidance of shrubland (clear-cuts and forests up to 30 years of age) and preference of continuous forest cover (older than 30 years of age) are characteristic of the Black Stork nest-site use. Nest-sites of Lesser Spotted Eagle in relation to ground cover did not differ from availabilities in the forest landscape, except in the environment nearest to the nest-trees, where eagles preferred continuous forest cover and weakly avoided shrubland. We assume that the relatively low avoidance of shrubland by both species could be related with the present level of forest landscape fragmentation, ongoing adaptation to the fragmented forests, or the importance of a suitable nest-tree with only the immediate surrounding to provide protective cover. Some implications for conservation are discussed. ... c0a4da.pdf

The Black Stork Ciconia nigra between the Sió channel and the Drava river in the central Danube floodplain: transboundary monitoring and protection plan
Marko TUCAKOV, Béla KALOCSA, Tibor MIKUSKA, Anna Eniko TAMAS, Antun ŽULJEVIĆ, Boris ERG & Tamás DEME
Abstract: The largest and incomparable inland floodplain of the Danube extends 130 kilometres along its banks in the area where the borders of Hungary, Serbia and Croatia meet. Most of the area is protected: Gemenc and Beda-Karapancsa as a part of the Hungarian Danube- Drava National Park, Gornje Podunavlje as a Special Nature Reserve in Serbia, and Kopački Rit as a Nature Park in Croatia. Forest stands and a variety of water bodies (river branches, oxbows, marshy depressions, and carp fishponds) dominate over the site - the most valuable ones are preserved in a 52,500 ha large recent inundation area. However, the area is still under strong human pressure, being used for forestry, water management, hunting, agricultural and recreation purposes. The Black Stork, as a flagship species of the area, strongly bounds during its life cycle all habitats in this transboundary site. Its local distribution, numbers, breeding habits, movements, threatening factors, and its conservation needs have been studied by the authors in the International Black Stork Colour Ringing Program. ... n-plan.pdf

Breeding density, spacing of nest-sites and breeding performance of black storks Ciconia nigra in Dadia-Lefkimi-Soufli Forest National Park, north-eastern Greece
Olga ALEXANDROU, Dimitrios E. BAKALOUDIS, Malamati A. PAPAKOSTA and Christos G. VLACHOS
Abstract: Breeding densities and the breeding biology of the black stork Ciconia nigra were studied in Dadia – Lefkimi – Soufli Forest National Park, north-eastern Greece, during 2006–2008. One hundred and one breeding attempts were monitored during the 3-year study period. In total 271 fledglings were successfully raised during that period. Black storks arrived in the study area between the last days of February and mid- March. Mean fledging date was 16 July. An average of 3.26 fledglings per successful pair (n = 83) were produced. The mean nearest neighbour distance between occupied nests was 1.09 km (1SD: 0.94, n = 33). Nests containing fledglings were recorded as close as 228 m. The population density was calculated at 8.1 pairs/100 km2 for the whole study area. The steady increase of the black stork population in the study area during the last few decades is partially attributed to the intensification of agriculture at small scale, which has created ideal feeding grounds for the species. The establishment of shallow artificial ponds in grasslands or along streams within the protected area may improve the availability of food resources for the species. ... 6ba35a.pdf

Can intensified forestry be responsible for changes in habitat usage by the forest-dwelling Black Stork?
Rimgaudas Treinys, Gintautas Mozgeris and Saulis Skuja
Abstract: Populations of the internationally protected Black Stork Ciconia nigra in the northern parts of the distribution range, located to the east of the Baltic Sea, have suffered decline over recent decades. Since early 1990s, however, logging intensity has increased. In this paper, considering a ten-year period from the mid-1990s, we ask: (a) Did changes occur in the habitat preferred by Black Stork in the decade? (b) did the decade of intensified forestry significantly change forest characteristics? and (c) could the intensified forestry explain any observed changes in the utilization of habitat by storks? We compared forest characteristics at the beginning and end of this period at 75 random points and compared the habitat at 75 nest sites occupied by the Black Stork in the mid-1990s and 75 occupied nest sites at the end of the 2000s. In the 0.7-km zones around the random points, the abundance of mature stands decreased between the mid-1990s and the end of the 2000s, as did the abundance of broadleaved trees, but black alders increased. Nevertheless, the age and composition of tree species within the stands around the random points remained similar. Some changes were noted though in the habitat around nests used by Black Storks during two periods, with the data indicating that the Black Storks tended to occupy sites of better habitat quality (e.g. with a higher density of hydrological network and old oak trees, older nest stands) at the end of the 2000s than in the mid-1990s. Our results, however, do not support the idea that intensified forestry over the short term induced changes in the habitat used by the Black Storks. It is possible that nesting Black Storks became concentrated into the prime habitat when population retracted and/or abandoned habitat where recently recovered by the White-tailed Eagle. ... 016-1003-6

Population Trends and Multi-Scale Breeding Habitat Analysis for the Black Stork (Ciconia nigra) in Dadia-Lefkimi-Soufli National Park, North-Eastern Greece
Konstantinos Poirazidis, Vasileios Bontzorlos
Aims: The aim of the study was to assess Black stork (Ciconia nigra) population trends and breeding habitat preferences in two habitat scales, in the National Park of Dadia-Lefkimi-Soufli (Dadia NP), in north-eastern Greece. Dadia NP is a renowned European biodiversity hot-spot (N 40° 59' to N 41° 15', E 26° 19' to E 26° 36').
Study Design: The Black stork breeding population was monitored under the Systematic Raptor Monitoring Scheme (SRM), which was established in the area by World Wildlife Fund (WWF) Greece.
Place and Duration of Study: The study was conducted in Dadia NP with annual monitoring efforts from 2001 until 2006, and once again in 2012.
Methodology: Twenty-four vantage points and ten road transects were selected throughout the entire study area. All Black stork individuals were surveyed and mapped during five months (March to July), for each monitoring year. Nesting habitat was measured in two scales. To assess the microhabitat, nesting-trees and vegetation variables were measured in a circular area of 0.1 ha (radius 17.85 m) around each nest. For the macro-habitat scale, a total of ten environmental variables were analyzed to model habitat suitability. MaxEnt software was used using high spatial resolution satellite data for each monitoring year.
Results: Black stork territories increased in Dadia NP from 24 pairs in 2001 to 33 pairs in 2012 demonstrating a total of 34.7% relative increase. According to Man Kendal tests, the species had a positive MK slope (1.7) which although not significant (tau = 0.69, P = 0.08), denoted a continuous increase. Increasing trends were corroborated by GAM models. The Black stork generally used large mature trees for nesting in sparse forests patches. The variable “elevation” demonstrated the most useful information for habitat modeling. During all monitoring years, Black stork showed a clear preference for the lowlands close to arable fields and wetlands which were used for foraging. Following the positive trend of Black stork population, the species’ suitable nesting habitat also extended from 48% in 2001 to 72% in 2012. ... 6261/49252

GIS-based modelling to predict potential habitats for black stork (Ciconia nigra) in Sweden.
Sörhammar, Malin
Abstract: The black stork (Ciconia nigra L.) was lost from the Swedish fauna in the 1950’s. An increased understanding of the need to save endangered species has led to restoration or preservation of populations through reintroductions. To have background information about a species’ habitat requirements is important for introduction programs. A habitat model can be used to predict the requirements of the species, and provide suggestions for areas suitable for reintroduction. In this study, a Geographical Information System (GIS) is used to create a model to identify suitable habitats for a potential reintroduction project of black stork in Sweden. The geographical extent in the analysis was limited to the former distribution range of black stork in the southern part of Sweden. My results indicate several suitable black stork habitats in all counties included in the analysis, except the Baltic Sea Island of Gotland. Seven counties contained more than 18 % suitable habitats in relation to the total area of each county. I suggest that these areas should be the primary target areas for black stork reintroduction to Sweden. ... 150205.pdf

Nesting of the black stork (Ciconia nigra) and white-tailed eagle (Haliaeetus albicilla) in relation to forest management
Raul Rosenvald, Asko Lõhmus
Abstract: Since 1957, 200 m zones around known nests of the black stork (Ciconia nigra) and white-tailed eagle (Haliaeetus albicilla) have been strictly protected in Estonia. Yet, the black stork population has recently suffered a large decline, which coincides with the intensification of forestry. To check whether higher disturbance levels could have caused the decline, we related the extent of forestry operations and mature forest near black stork nests to their occupancy, treating the increasing eagle population as a comparison. For both species, we studied 1 km zone around 38 nest sites and, for each nest site, around two random points 2 km away. The total annually cut and reforested area was used to quantify forestry activity, since this single variable explained most of the variability in the extent of different forestry operations. Management was significantly more extensive in the landscapes inhabited by black storks than those inhabited by white-tailed eagles, but the periods of nest occupancy and unoccupancy did not differ significantly in either species. There were neither species-specific nor occupancy-related differences in the total area of mature forest. We conclude that, compared with the white-tailed eagle, the black stork is more vulnerable to disturbance and landscape change due to forestry operations, but these processes are probably not responsible for the recent decline of the stork population. ... 2703002160

Have recent changes in forest structure reduced the Estonian black stork Ciconia nigra population?
Asko Lõhmus, Urmas Sellis, Raul Rosenvald
Abstract: The black stork Ciconia nigra is listed as a focal species for guiding forest management in Estonia, where forestry has recently intensified and the stork population has suffered a twofold decline. We explored a possible link between the decline of the population and man-induced changes in forest structure, by analysing nesting of the species in relation to forest cover, edge effects and stand structure. Although the storks had distinct habitat preferences (old remote stands near rivers and a certain distance far from ecotones in well-forested landscapes), these were hardly reflected in site re-occupancy and productivity. Therefore, changes in forest structure are probably not responsible for the population decline, although preferences for specific forest environments may limit the range of potential nest sites. The results indicated that edge avoidance cannot be considered a species-specific feature over large areas and clear habitat preferences are not necessarily related with the present success of a population. We also suggest that lists of focal species should be regularly updated and validated in the field. ... 004-9667-5

Contributed by Ari19
Nest trees - a limiting factor for the Black Stork (Ciconia nigra) population in Estonia
ABSTRACT - To assess the role of nest trees as a limiting factor for the Black Stork population in Estonia, we have described 49 nest sites and have explored the availability of potential nest trees in randomly selected plots. Compared with the composition of neighbouring nest stands, the storks strongly preferred to nest on oaks and aspens, followed by pine, and avoided spruce. Our analysis shows that the disproportional use of tree species could be explained by their canopy structure, notably the opportunity to hold a large nest away from the main trunk. On average, the nest trees were 25.6 m high, 120 years old and had a 66-cm diameter at breast height. Different tree species became suitable at different ages. Similarly to the other Baltic countries, nest trees were older than nest stands, showing that older tree retention during forest management practices is important for the species. In a random landscape, 3.5% of forest land contained at least one tree suitable for nest building, but after considering also stand structure and location, only 0.3% of forest land could be listed as suitable. We conclude that the shortage of potential nest trees is severe enough to limit the Estonian Black Stork population, and that sylvicultural management for retaining or creating such trees in forested areas are by far under-used. ... 1-4_84.pdf

At the border of ecological change: status and nest sites of the Lithuanian Black Stork Ciconia nigra population 2000–2006 versus 1976–1992
Rimgaudas Treinys, Asko Lõhmus, Darius Stončius, Saulis Skuja, Eugenijus Drobelis, Bronius Šablevičius, Saulius Rumbutis, Deivis Dementavičius, Vladas Naruševičius, Antanas Petraška, Danas Augutis
Abstract: Recent trends in the European Black Stork Ciconia nigra population are geographically distinct: range expansion and adaptation to human activity dominate in western and central Europe, while declines—probably induced by landscape change—are reported in the east. We studied the large Lithuanian Black Stork population in the transition zone to explore whether, and how, the detrimental influences of recent Baltic landscape changes are balanced by the West European tendency of behavioural adaptation to human activity. Based on monitoring in sample plots, the current population was estimated at 650–950 pairs, indicating a significant decrease (possibly over 20%) during the last two decades. In comparison to the Latvian and Estonian populations, however, this decline is smaller, and the reproductive success remains at a high level [66% breeding success and 2.99 ± 0.97 (SD) fledglings per successful attempt, 2000–2006]; this north–south gradient suggests a climate-mediated impact of habitat degradation in the Baltic countries. The storks are also nesting closer to forest edges and in younger stands than 15–30 years ago, which has probably reduced the nest-tree limitation, as indicated by an increased use of large oaks. Thus, habitat degradation and adaptation seem to be taking place simultaneously in the Lithuanian Black Stork population, as was expected from its geographical location. In general, our study supports the view that, whenever possible, species conservation strategies and the use of indicator species should be geographically explicit. ... 007-0220-7

The role of ponds as feeding habitat for an umbrella species:
best management practices for the black stork Ciconia nigra in Spain

Rubén Moreno-Opo, Mariana Fernandez-Olalla, Francisco Guil Angel Arredondo, Rafael Higuero, Manuel Martin, Carlos Soria and José Guzman
Abstract To establish recommendations for wetland management that promote wildlife diversity in Mediterranean habitats we examined the factors that determine feeding habitat selection by the black stork Ciconia nigra in ponds. The black stork is considered an umbrella species because it is threatened, requires large foraging ranges in priority areas, is selective in its choice of diet and nesting sites, and inhabits a characteristic biological community with endemic and threatened taxa. Eighty-five ponds were monitored in central and western Spain to detect the stork feeding. At the same time, pond variables that could affect black stork feeding preferences were periodically evaluated. Generalized linear mixed models were used to analyse principal components obtained from groups of factors related to structural, location and ecological conditions. The black stork selects ponds distant from roads, with a large surface area, high water level, shallow shores, low turbidity, few traces of wild ungulates on the shores, a high diversity of fish and amphibian species, and a vegetated perimeter, in flat and open areas. Potential factors affecting feeding behaviour are discussed. We suggest measures for pond construction and management that could favour this species in particular and biodiversity in general in the Mediterranean environment. ... eab45d.pdf


Conservation ecology and landscape planning usually can deal with many data from the community level (e.g., Beja & Alcazar, 2003; Benayas & de la Montana, 2003; Kitahara & Watanabe, 2003) or using well known focal and umbrella species (e.g., Coppolillo et al., 2004; Roberge & Angelstam 2004) but in case of endangered and/or rare species, only few data could be available (e.g., Bearzi et al., 2003; Lovett-Doust et al., 2003; Stringer et al., 2003). In addition, in recent cases of arrival or spontaneous recolonization of new areas, species ecological requirements may be different from those known in other areas.
This is the case of the Black Stork, Ciconia nigra (Linnaeus, 1758), which became extinct as an Italian nesting bird, probably during the Middle Age, and naturally re-estab- lished successful breeding pairs since 1994 (Bordignon, 1995, 1999). In their analysis of the potentiality of the Italian area for all vertebrate species, Boitani et al. (2002) based their work on the Black Stork mainly on two variables: presence of (1) wet lowland woods with ponds where to feed and (2) old and large trees where to nest, as it was known from the lit- erature but from other countries. These assumptions gave a high potential for this species to areas which are not used; moreover, the actually used area in Northern Italy resulted as not really potential, i.e. pointing to a discrepancy between previous knowledge and actual requirements. It is of pivotal importance to know which environmental features the Black Stork prefers, as it is one of the species which can drive the institution of Areas of Special Protections, by the EEC directives “Birds” 79/409/CEE and 91/244/CEE. The use of money for environment conservation in relation to this species has to be based on its actual require- ments. Hence, the aim of this work is to clarify the environmental features which are actu- ally needed by this charismatic species in its nesting area in Northern Italy. Moreover, due to the lack of available data on this rare species, we used resampling statistics (Manly, 1997), which can be a useful way to bypass the problem of few data in case of need of indi- cations for political decisions about endangered species. ... 1569068464

Breeding Habitat of the Black Stork Ciconia nigra in Lithuania:
Implications for Conservation Planning

Abstract: A significant part of the European Black Stork population breeds in Lithuania. However, the preferences by this species for macrohabitat and microhabitat features have not been analysed statistically until now. In this study, we analyzed field material collected in the last 8 years with the aim of establishing: 1) which habitat characteristics are preferred by the breeding Black Stork at macrohabitat and microhabitat scales and 2) which habitat features should be considered in the planning of Special Protected Areas for the Natura 2000 network aimed at protecting the species and the selection of set aside areas under the sustainable forestry schemes. At the macrohabitat scale Black Stork significantly preferred only dense hydrographical network. Preference for older, productive stands with greater share of broadleaved trees, nesting in forest interior and avoidance of proximity to water bodies and stands with grey alder are the most characteristic features of Black Stork microhabitat in Lithuania. A list of criteria to be used in selection of forest stands potentially suitable for Black Stork nesting was developed. ... 033_40.pdf

Contributed by Ari19
Factors affecting the nest site selection of the black stork, Ciconia nigra in the Dadia-Lefkimi-Soufli National Park, north-eastern Greece
Christos G. VLACHOS1, Dimitrios E. BAKALOUDIS, Olga G. ALEXANDROU, Vasileios A. BONTZORLOS and Malamati A. PAPAKOSTA
Abstract: Nest site preference of black stork nesting in the Dadia-Lefkimi-Soufli National Park, northeastern Greece was studied through the 2003 - 2004 field seasons. Seventeen nest- trees and their surroundings (0.1 ha circular plot centered at nest-tree) were described and compared to the characteristics of the same number of paired, randomly selected plots. Black storks usually nested in old pines, on branches at a mean distance 1.5 m from the trunk or against the trunk. Nest sites were located at slopes significantly steeper and significantly closer to small streams compared to random plots. The total tree density at nest sites was significantly lower and the mean canopy closure immediately adjacent to black stork nest trees was also significantly lower compared to that adjacent to the randomly selected trees. Nest sites had lower tree basal area than randomly selected sites, suggesting that the less wood volume sites were preferred for nesting by black storks in the study area. ... _stork.pdf

The role of forest reserves in the protection of the Black Stork Ciconia nigra in central Poland
Abstract: The black stork Ciconia nigra in central Poland (Łódź voivodship) increased from about 3 breeding pairs in the 1940s to 59 pairs in 2003. The density of the BS was 0.3 pairs per 100 km2 of the total study area in 2003, 1.6 pairs per 100 km2 of forested area and 3.3 pairs per 100 km2 of forests older than 60 years. Eleven pairs of black storks built their nests within the boundaries of the forest reserves, 34 pairs had nests outside the forest reserves, and six pairs had one nest inside and one nest outside the reserves. Thus, the black stork shows a strong tendency to build nests in the forest reserves. The greatest increase in the number of breeding pairs in central Poland was recorded in the 1970s. At that time, most of the forest reserves were already established, making growth in the number of pairs possible. Forest reserves protect old-growth stands, which provide breeding trees for the storks. In addition, forest reserves serve as refuges from human encroachment and are thus of crucial importance for long-term protection of the breeding sites of the black stork. ... ral_Poland

Application of Geographic Information System (GIS) Technologies in Identification of Potential Nesting Habitats of Black Stork (Ciconia Nigra)
Danas Augutis & Stanislovas Sinkevičius
Abstract: The article analyses data on the negative or positive impact of independent abiotic/biotic (including anthropogenic) factors on the selection of breeding habitats and specific nesting sites by Black Stork (Ciconia nigra). Based on the analysis of environmental data for particular nesting sites of Black Stork, the modelling of suitable nesting areas was performed in forested territories – in the Giedraičiai and Glitiškės forest districts. A detailed assessment of suitable nesting areas for Black Stork, with the highest likelihood of the species’ breeding, was made with the help of GIS and local envirospace modelling. Eventually, a further extrapolation of generalised research results to much larger territories on the scale of the entire country or even region is possible. ... 5.10512603

Breeding Productivity in Relation to Nesting Substrate and Nest Site Accessibility to Humans in the Black Stork Ciconia Nigra
Luis Santiago Cano-Alonso, José Luis Tellería
Abstract: The black stork Ciconia nigra is a threatened tree-nesting species in Europe. The relatively poorly studied and isolated Iberian population is unusual in Europe in that the majority of known pairs are cliff-nesting. This permits the analysis of productivity differences in relation to nesting substrate in different subpopulations, comparing not only the mean number of fledged chicks/nest between cliff-nesting and tree-nesting pairs but also considering whether the nests are located in restricted- or open-access areas. The results reveal that nesting substrate does not determine differences in productivity. Only those cliff-nesting pairs that breed in open-access areas have significantly lower productivity than pairs that breed elsewhere. Therefore, whether or not black storks nest on cliffs and on trees should not have a relevant effect per se on the productivity of the species but such an effect may arise in relation to the degree of human access to the cliff-nesting sites. Further in-depth research is needed about the exact causes of lower productivity in pairs that nest on cliffs located in open-access areas. ... .357.short ... 7dbc05.pdf

Satellite tracking of breeding black storks Ciconia nigra: new incomes for spatial conservation issues
Frédéric Jiguet, Stéphane Villarubias
Abstract: Satellite tracking of black storks was used to estimate home range sizes and to study habitat selection during the breeding season. Breeding and non-breeding adults foraged over very large areas (ca. 54 000 ha for 12 territories), preferentially in woodlands with high number of river sources, mirroring the species needs for high quality water resource. Rearing and post-fledging ranges of breeding partners largely overlapped. Home ranges of non-breeding adults largely overlapped ranges of breeding birds, so that assessing home range size of breeding pairs from observed densities is not reliable. Protection and management of breeding and feeding habitats appear to be the most important conservation measures to be considered. This study allowed to evaluate how large these protected areas should be, and which habitat types they should encompass. Conservation measures for the species in western Europe should include protection of very large forest areas and also focus on managing river networks to ensure a high water quality as far as 20 km away from nests. ... lStork.pdf

May sympatric Lesser Spotted Eagles and Black Storks compete for nesting sites in spatially varying environments?
Saulis Skuja, Gintautas Mozgeris, Rimgaudas Treinys
Vol 25 No 1 (2019): Baltic Forestry

Sympatric species are likely to compete with one another unless there is a low degree of overlap in their resource use, in which case these species are able to coexist. Disclosing of biotic interactions between sympatric species is important from both theoretical and practical perspectives, especially when the species are of conservation concern. However, environmental heterogeneity may introduce variation in the intensity of biotic interactions due to differential a varying species responses to the environmental gradient. In this study, we analysed the overlap in nesting sites between the internationally protected, mature, forest-dwelling Lesser Spotted Eagle Clanga pomarina and the Black Stork Ciconia nigra. The importance of landscape heterogeneity for habitat segregation between these species was also assessed. The nesting sites of 123 pairs of Lesser Spotted Eagles and 78 pairs of Black Storks, located across different landscapes of the Central, Central-Eastern and Eastern Lithuanian ecoregions were described. A series of discriminant analyses were performed to explore the pattern of habitat differentiation between species nesting in the above-mentioned regions. The habitat differentiation was estimated by niche overlap values (range 0-1, with a value 0.6 suggested to be the threshold between coexistence and competition). Comparison of nesting sites of mature forest-dwellers resulted in the niche overlap values for Central, Central-Eastern and Eastern regions being 0.5, 0.63 and 0.55, respectively. These results indicated relatively high niche overdispersion between nesting sites occupied by eagles and storks. Different variables and/or their combinations resulted in habitat differences in each ecoregion. Our data indicate that biotic interaction between species is mediated by environmental heterogeneity. Although our data tend to support the coexistence of the Black Stork and the Lesser Spotted Eagle, in certain regions these mature, forest-dwelling predators may use similar habitats and compete for prime sites under specific landscape structures. We, therefore, propose the necessity of the importance of a spatially-segregated estimation on biotic interactions when developing conservation programmes and allocating conservation actions within the target region. ... oad/134/59

Black Stork (Ciconia nigra) – Hungary 2018
Prepared by Katrina Abhold
Summary: The Black Stork (Ciconia nigra) is a waterbird species that breeds in Europe, with most of its population migrating to Africa in winter. Although it is scarce, its threat status is considered to be Least Concern both globally and within Europe, as its population has been increasing. It predominantly feeds in wetlands, but requires old, undisturbed and open forests with old trees with large canopies for nesting. The main pressures and threats to the species are human-induced habitat degradation caused by deforestation, the rapid development of industry and farming, as well as the construction of dams and drainage of lakes for hydroelectric power production and irrigation. The species is also highly sensitive to human disturbances and will abandon its nests due to the presence of foresters and hunters. The principal conservation measures that have increased the Black Stork’s population have included the restoration of wetland and nesting habitats and the construction of artificial pools for feeding. LIFE projects, such as the ‘Conservation of endangered bird species populations in natural habitats of the Danube inland delta’, have helped restore such areas and raised awareness of the species and its needs with local communities. ... 7CVKj-7poB

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Re: What We Know About Black Storks

Posted: August 12th, 2019, 12:57 am
by Anne7
Black Stork Courtship Displays and Territories

Contributed by Ari19
Form and function of aerial courtship displays in Black Storks Ciconia nigra
Peter Sackl
Abstract: Hitherto unknown aerial courtship displays of Black Storks Ciconia nigra recorded for the most part during population surveys in northern and eastern Austria between 1979-1991 are described. Aerial displays were seen mainly during the early stages of the breeding cycle in April till mid-May (Fig. 1). They are characterized by mates soaring tight together in a highly synchronized manner above the nest-site or in other parts of the home range (ParallelSoaring). Additionally, melodious flight calls are given by both partners and the white undertail-coverts are widely spread. Occasionally soaring birds were seen whiffling or performing simultaneous darting flights (Fig. 3). According to (1) the regular participation of both breeding partners, (2) their regular performance around nest sites and/or within home ranges, (3) their largely restricted occurrence during early stages of the breeding cycle as well as (4) by their specific pattern of stereotyped and elaborated behavioural elements(Parallel Soaring, Displaying the Undertail-Coverts, Flight Calls, Whifflingand Darting Flights) ceremonial flights in Black Storks may generally operate as highly ritualised courtship flights. Thus, analogous to aerial displays in other large forest-living birds – like in many raptors – they may help in point-ing out nest-sites to potential mates, stimulate pair formation and assist in spacing by discouraging other birds from settling close. The highly elaborated courtship flights in Black Storks seem to be unique within the “typical” storks of the tribe Ciconiini and coincide with the solitary nesting habit of the species within the closed canopies of heavily wooded areas. ... onia_nigra

Males, Females and Black Stork Nests: Who Owns What and Do They Hold Territories?
Maris STRAZDS, Laboratory of Ornithology, Institute of Biology, University of Latvia, Latvia
Extensive ringing programme of Black Stork juveniles in Latvia started in 1990. Up until 2017, 1,603 juvenile storks had been ringed. In 2011, first remote sensing cameras were installed, and one of the nests has been permanently observed with a webcam since 2015. As of 2016, data from 20 cameras can be explored simultaneously. Obtained material comprises more than 1.2M pictures collected near 92 nests. From this material, more than 772K pictures from 41 nests, along with the videos filmed at two webcam-equipped nests, have been used for analyses of territorial behaviour and mate choice during the breeding season. In this talk, I discuss the validity of the widely explored concept of the "territorial” or “non-breeding pair" – a parameter that strongly affects all indices of productivity for any given territory. The data obtained exclusively from observations of ringed individuals with known sex and other individually identifiable birds suggest that this term is not relevant for Black Stork, consequently, all breeding success data should be reassessed. Similarly, the assumption that males own the nest appears not to be correct at least in some cases. The question whether it is true only for Storks in the surveyed range or characterises species as a whole should be the subject of a wider study over much larger territory in the future. ... t-Book.pdf

Beth Slikas
Evolution; International Journal Of Organic Evolution, 1998

Ethological studies in the 1940s and 1950s, most notably those of Lorenz and Tinbergen, emphasized a historical perspective. By the 1970s, the notion that behavioral traits are too plastic to retain historical information became prevalent, and evolutionary approaches in behavioral studies were largely abandoned. However, several recent studies have demonstrated that behavioral characters are remarkably consistent with phylogenies obtained from other data and not particularly prone to homoplasy. In this study, I coded descriptions of courtship display behaviors in stork species (Aves: Ciconiiformes: Ciconiidae) as a matrix of discrete characters. I mapped each behavioral character onto a phylogeny based on DNA-DNA hybridization distances to test the homology of individual characters. Generally, displays occurring early in courtship were congruent with phylogenetic relationships and showed little homoplasy, while displays occurring late in courtship were more homoplastic. I also performed a phylogenetic analysis of the behavioral data matrix using maximum parsimony. The strict consensus of the 24 most-parsimonious trees was congruent with the DNA-DNA hybridization tree in all nodes having greater than 70% bootstrap support. ... .tb03713.x

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Re: What We Know About Black Storks

Posted: August 12th, 2019, 12:58 am
by Anne7
Reproduction, Eggs and Brooding

Contributed by Ari19
The structure and composition of the white and black storks’ eggshells – preliminary results
Bartosz Budzyń, Piotr Profus
Eggshells of the white and black storks were investigated in terms of their structure as well as mineralogical and chemical composition. Analyzed samples of the white storks’ eggshells revealed higher thickness, lower porosity and higher content
of organic “micronet” than eggshells of the black storks.
Avian eggs form a relatively closed system in terms of energy flow — they exchange only gases (O2, CO2, and water vapor), but not solid or liquids with their environments. The shell of an egg, which serves as a barrier between the embryo and the external environment, must be sufficiently thick and strong to support the mass of the contents and incubating adult (Carey 1996). One of the most recent nomenclature applied to eggshell structures was proposed by Board, Sparks (1991).
These authors distinguished following structures (from outer to inner part of the eggshell): shell accessory materials, surface crystal layer, palisade layer, cone layer, basal caps, shell-membranes and limiting membrane. All of these — apart from membranes — build the so called true shell (Tyler 1969).
In this paper we report preliminary results of determinations of structure and variability of chemical compounds within the true shell of the white and black storks. ... ry_results

Contributed by Ari19
Predominance of maternal investment during the incubation period in the Black Stork
Cano Alonso L.S., Hopwood C.R. & Fernandez M.
Some details of the reproduction biology of the Black Stork were studied on one model pair in Madrid region. Duration of incubation, time of incubation spent by each mem- ber of the pair, duration and intervals of relief for incubation, bringing of materials for the nest... We can conclude that both members of the pair collaborate in all tasks but that the female invests the most effort during the incubation period.
Full Text
During a study aimed to follow the population of Black Storks (Ciconia nigra) in Madrid region (the centre of Spain), we observed that the per- iod of incubation is one of the most critical moments for the success of a reproductive pair. In this region, this period ranges from the first week of March to the middle of June. A close tracking has given us the opportunity to observe with precision some details of the reproductive biology of this species during its daily activities. To carry out the study we followed one model pair, obtaining the following results.
The period of incubation lasted 38 days, after which 4 eggs from that nest hatched asynchro- nously, which is described in any classical hand- book of ornithology (BAUER & GLUTZ, 1966; CRAMP & SIMMONS, 1977; DEL HOYO et al., 1992). Eleven copulations were observed, all of these in the first week of incubation. For 9 timed copulations there was a mean of 10.7 seconds per copulation (the range was between 4 and 15 seconds). There exist significant differences in the time of incubation spent by each member of the pair (Mann-Whitney; U=0.00, p<<0.001). While the female incubated for 58.34 % of the time (X=507.54 min/day, S.D.=33.40), the male only incubated 41.66 % of the time (X=351.27
min/day, S.D.=47.21). The intervals of relief for the incubation were very irregular. Of 48 controlled reliefs, the mean was 3 hours and 19 minutes, a time perceptibly greater than that observed for the White Stork (Ciconia c. ciconia) in the Iberian peninsula (CHOZAS, 1983). At all time at least one member of the pair stayed in the nest with the eggs. The time that the pair was in the nest together varied throughout the period of incubation. During laying of the eggs, the two individuals were in the nest together up to 20.5 % of the time, decreasing to 3.8 % before hatching of the eggs, at which point the time spent on the nest together increased once again to 8.4 %. Across the whole period of incubation the pair was in the nest together for 11.6 % of the daytime.
Throughout the time of incubation, we also observed a variation in delivery of material to the nest. The arrivals during the laying period (14) and during the hatching period (18) made a total of 32 deliveries of material. Again it is the female that was most involved in this work with 25 deliveries attributed to her. This is contrary to the described tendencies of other species of the Ciconiidae family (GONZ¡LEZ, 1992).
Using the obtained data it can be concluded that during the period of incubation of the Black Stork there is a sex-based difference in func- tions. Although both members of the pair colla- borate in all tasks, as described in the literature to date (BAUER & GLUTZ, 1966; CRAMP & SIMMONS , 1977; DEL HOYO et al., 1992), it is the female who invests the biggest effort during the period of incubation. Up to now, this had not been reported in the reproductive biology of this species in particular, nor for the family of Ciconiidae in general. Finally, although the data
above are based on observations of one single pair, the tendency has been confirmed (without such an exhaustive recording of behaviour) in other pairs breeding in the area of the study, and in other European populations, as in France (Laguet S., personal comment), so that it appears to be a generalized behavioural pattern. It would be desirable to extend such studies on other pairs because of the lack of knowledge about the behaviour of the species, in general terms. ... lack_Stork ... 1-4_72.pdf

Elemental Composition and Ultrastructure of Eggshells of White Storks and Black Storks on Condition of Artificial Rearing
Su Haijun, Ma Jianzhang, Tian Xiuhua(Northeast Forestry University, Harbin 150040, P. R. China)
A study was conducted to determine the elemental composition and to scan the ultrastructure of eggshells of captive white storks and black storks. Results showed that the content of N, Fe, P, Hg in white storks’eggshells is higher than that in black storks’, but Na does conversely. Heavy metal pollutant such as Pb, Cd, Sr, As and Hg were examined out in eggshells of both white stork and black stork, which indicates that the mother bodies have been polluted. The eggshells of both are divided into four layers: surface crystal layer, palisade layer, mammillary layer and shell membrane. In the aspects of ultrastructure, the shape of pore in white storks’eggshells is more regular and the wall of pore is smoother than those in black storks’, and the fibre density of shell membrane of the white storks’ are denser and arranged like bamboo forest. It is concluded that there are interspecific comparability and variability between these two relatives concerning physiology, genetics and phylogenesis. ... 601019.htm

Egg size variation in the White Stork (Ciconia ciconia)
Piotr Profus, Piotr Tryjanowski, Stanisław Tworek, Piotr Zduniak
White Stork (Ciconia ciconia) eggs were studied in Upper Silesia, Southern Poland. The measurements of eggs – their length, breadth, volume and elongation index were collected for 95 nests in years 1974–2002, and repeatability of these measurements was computed. Mean clutch size was 4.05 ± 0.82. Mean egg measurements were: 72.10 ± 2.18 mm, 52.19 ± 1.47 mm, 100.49 ± 6.92 cm3 and 1.38 ± 0.05, for length, breadth, volume and elongation index, respectively. Coefficients of variation for clutch means ranged from 1.68 (breadth) to 4.37 (volume). Mean repeatability estimates were 0.53, 0.68, 0.63, 0.58 for length, breadth, volume and elongation index, respectively. The results obtained suggest that one should expect relatively low or intermediate heritability of egg dimensions in population studied. ... ia_ciconia

More information on the reproductive and urogenital systems (birds in general) » viewtopic.php?p=688474#p688474

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Re: What We Know About Black Storks

Posted: August 12th, 2019, 12:59 am
by Anne7
Brood Reduction and Parental Infanticide among Black Storks


Are the White Stork Ciconia ciconia and the Black Stork C. nigra exceptional?
Piotr Zielinski
Abstract: Brood size in birds is reduced through fatal starvation, siblicide or parental infanticide (killing of own offspring). Both Black and White Storks were observed practising facultative parental infanticide. In the White Stork, parents regurgitate large amount of food consisting of many small items on the nest bottom. Chicks pick up food themselves, trying to eat as quickly as possible. No aggression among chicks is observed. As a result, monopolisation of food does not occur and elimination of the weakest chick is very ineffective. Sometimes parent storks accelerate brood reduction by killing some of the offspring. Surprisingly, although parental infanticide is a quick and efficient method of brood reduction it is rarely observed, even in species practising it. ... xceptional

A case of parental infanticide in the black stork Ciconia nigra.
Grzegorz Klosowski, Tomasz Klosowski and Piotr Zielinski
Killing conspecific nestlings by an adult bird is usual-ly observed in the context of sexually selected infanticide and it is the new breeding partner who kills the young (Hrdy 1979, Fujioka 1986, Banbura & Zielins-ki 1995). Very rarely chicks are killed by the parents(parental infanticide). Parental infanticide may save energetic resources otherwise wasted by a low-quality chick that will probably not survive, and the resources saved may enhance the probability of successful fled-ging by the surviving brood members (Mock & Parker1995). However, parental infanticidal behaviour has been observed, for example, in the white spoonbill Platalealeucorodia (Aguilera 1990), Heerman’s gull Larusheermanni(Urrutia & Drummond 1990) and the white stork Ciconia ciconia (Schüz 1957, Jakubiec 1991, Tortosa & Redondo 1992, see also review by Mock &Parker 1997). This study reports a clear case of parental infanticide by the black stork Ciconia nigra. ... onia_nigra

English translation by Trine
Why do birds kill their chicks?
Tuul Sepp
This year, as well as in previous years, the black stork webcam watchers have been witnessing events that appear to be incomprehensible and dreadful. One of the recently hatched fluffy-balls has been tossed to the nest rim and doomed to death, or even eaten up by its parents.
Infanticide as a means of regulating the brood size is not universal, but still quite common phenomenon among birds, particularly the species that are relatively big in size. The reason lies almost always in the limited resources, i.e. the parents do not have enough energy, time and food to nurture and feed all of their chicks.
Does this mean that the bird should have laid a smaller number of eggs? This would have been a very big mistake: what if some of the eggs would not have hatched? It is wise of a bird to lay more eggs, just in case. The reserve egg serves as an insurance in cases when something misfortunate happens during incubation, or when the foetus dies inside the egg. For instance, spotted eagles mainly lay two eggs, but frequently enough the second egg is rotten. Despite this, there will be at least one chick and the breeding season is not wasted.
More eggs means that the bird can adjust the size of the brood at a later date, if necessary. The optimal number of offspring may vary between the breeding seasons, and when it becomes clear that this time all nestlings cannot be fed, their number can be reduced accordingly. If all of the eggs produce a chick and the resources turn out to be plentiful, then there is a chance to raise all nestlings.
Asynchronous hatching, observed in many species, provides an opportunity to adjust the number of nestlings. This means that one of the chicks hatches, begins to beg for food and grow well before its siblings. Other chicks hatch later, one by one. Compared to its siblings, the last hatchling is weak and feeble; it is not that capable of begging for food, and it gets parental care only if the food resources are particularly plentiful. If they are not, the chick dies, mostly of starvation, sometimes with the “help” of its siblings (in some bird species, for instance blue-footed booby, siblicide is practised in a,ll broods). In this way the number of chicks can be adjusted to the prevailing conditions.
“Brood reduction” like this is regularly practised by for instance raptors and seagulls. The common gull always has a clutch of three eggs, but the last egg is smaller and lighter than other eggs. This egg very rarely produces a viable offspring. On the other hand, to have a third egg as a reserve is a reasonable strategy.
A famous English demographer Robert Malthus once wrote: “Through the animal and vegetable kingdoms, Nature has scattered the seeds of life abroad with the most profuse and liberal hand; but has been comparatively sparing in the room and the nourishment necessary to rear them.” There is an enormous difference between the amount of resources that parents are able to invest in their offspring, and the amount of resources that the offspring require.
Ecologists call this parental optimism. There are two hypotheses to explain the parental optimism, i.e. the overproduction of offspring. The first is bet-hedging: do not put all your eggs in one casket or, in other words, do not invest in only a single offspring. The second explanation is a possibility to select the best individuals from the overproduced offspring. Among mammals, for instance, selective abortion of weak foetuses occurs. Both hypotheses can act at a time and lead to overproduction of zygotes in all spheres of living nature.
It is obvious that the siblings alone cannot be made responsible for coping with the consequences of the optimistic overproduction of their parents. Unlike newborn hyena cubs, most animals are not able to cut the throats of their siblings. Therefore, sometimes the parents themselves must make corrections to the number of their too optimistically produced offspring.
Infanticide, killing of offspring by adult individuals of the same species, is a widespread phenomenon in animal kingdom. No doubt, it occurs also among humans. Peter Freuchen, a Danish journalist and traveller who spent years among Greenlandic Inuit in the early 20th century, describes an exemplary case in his memoirs: “A mother had four children to feed, but no help was anticipated. Everyone knew her story – how she hanged three of her children to save them from starving to death. She was often referred to as a beautiful exemplary model of maternal love.”
So let´s be not too hard on the black stork mother who jostled her fourth chick away from the nest bowl. It could have been a decision of vital importance, to grant the survival of the remaining three fluffy-balls. ... i-tapavad/

Motives for parental infanticide in White Storks Ciconia ciconia
Francisco S. Tortosa and Tomas Redondo
White Storks Ciconia ciconia parents were observed to kill their smaller chick in 9 out of 63 nests observed during a three-year study. Infanticidal parents were caring for larger broods and laid larger clutches than non-infanticidal birds. Males killed the chick in 8 out of 9 cases. Victims were born from the last-hatched egg in 4- and 5-egg clutches, they were the lightest in their brood and grew at lower rates than their nestmates during the days preceding their elimination. The last-hatched nestlings in 4-chick broods had lower pre-fledging survival rates than their elder sibs. Potential victims contributed a low fraction to parents'reproductive output, and 4-chick broods were especially costly to raise because parents provisioned them both more frequently and for longer nestling periods. Hence, the presence of an extra chick seems to lower the benefit/cost ratio to parents rearing a large brood once its elder siblings have hatched successfully. If nestlings do not compete aggressively for food, parents would be selected to eliminate the extra chick themselves. This hypothesis could provide an explanation for the existence of parental infanticide also in other species. ... 000000.pdf

Infanticide in the nest of the storks... One life is sacrificed to save the others
URDAIBAI RESERVE (white storks), 14 July 2017
Last week we witnessed a dramatic event in the white storks' nest in front of the Urdaibai Bird Center. As we were observing the nest and its occupants, the adult stork started to attack one of its young. Having received many vicious blows to its neck, the young stork finally fell out of the nest. Members of the UBC later recovered the bird but it was seriously injured. It was taken to the Biscay Regional Government Wildlife Sanctuary but died two days later.
In birds, parental infanticide is a means of saving energy. By eliminating the individual which has the least chance of survival, the adults aim to increase that of the others. This type of behaviour has been observed in the Eurasian coot, the Mexican gull, the white stork and the black stork. In a study carried out in Andalusia, parental infanticide was observed in 15% of white stork nests.
In general, it is the male which kills the smallest of the young and this usually occurs when they are less than a week old. What makes the event in Urdaibai different is that the individual which was killed was more than a month old and therefore almost fully grown.
The reason for this unusual behaviour could be the disappearance of one of the adults who had been feeding the chicks. It would appear that after the death of its partner, the remaining stork was left with the impossible task of rearing three chicks alone. Faced with this situation it could only eliminate one of its dependents in order to guarantee the survival of the others.
Nature is very wise. Had it not done this the entire brood would have been put at risk.
So, hard though it may seem, one life was sacrificed to save the others. ... za-de-vida

Kind to kin: weak interference competition among white stork Ciconia ciconia broodmates
José María Romero and Tomás Redondo
Altricial nestlings in structured families show a diverse array of behavioural mechanisms to compete for food, ranging from signalling scrambles to aggressive interference. Rates of filial infanticide are moderately high in white storks. It has been hypothesized that this unusual behaviour is an adaptive parental response to the absence of efficient mechanisms of brood reduction (aggression or direct physical interference) by nestlings. To test this latter assumption, we analyzed video recordings of 41 complete feeding episodes at 32 broods during the first half of the nestling period, when nestlings complete 90% of growth and chick mortality and size asymmetries are highest. Parents delivered food to all nestlings simultaneously by regurgitating on the nest floor. No direct (bill to bill) feeding was recorded. Senior nestlings were never observed to limit their junior nestlings from eating food, either by aggression or physical interference. Experimental feeding tests revealed that heavier nestlings handled prey items more efficiently and ate food at a higher speed. The high degree of tolerance shown by senior nestlings is unusual among birds with similar ecological and phylogenetic affinities, such as herons. Tolerance by seniors cannot be easily explained by the absence of parental favouritism or proximate factors known to affect the occurrence of sibling aggression in other species (rate of food transfer, brood size, hatching asynchrony or length of nestling period). ... /Tomás.pdf

Other birds

Parental infanticide in birds through early eviction from the nest: rare or under‐reported?
Juan Moreno
Avian parental infanticide is apparently a rare phenomenon judging from the scant reports in the literature. However, unexplained cases of single nestling disappearance or of apparent fall from the nest are rather common and are routinely attributed to parental eviction of dead nestlings, single chick predation or dislodging of nestlings through errors by nestlings or parents. During long‐term studies of pied flycatchers Ficedula hypoleuca in central Spain, 29 cases of eviction from the nest cup of mostly hatchlings or small, heterothermic nestlings were recorded, leading invariably and quickly to death. Parental errors and failed attempts to predate single chicks are unlikely in these cases. Although the incidence of recorded evictions was mostly below 5% of nests, it reached higher levels in years and populations where reproductive success was low. Some cases were preceded by prior egg eviction. In these studies, there were unexplained disappearances affecting 3.7% of eggs laid which amounted to 20% of all losses. During studies of three other passerine cavity-nesting species, similar cases were observed. The rarity of reports of parentally evicted nestlings is apparently based on the difficulty of directly observing parents evicting live nestlings but may also be due to observer bias as ejections of dead nestlings, erroneous dislodgings or single‐chick predation events are also rarely observed but are normally given as reasons for single‐chick losses. Field researchers should attempt to determine the real causes of partial brood loss before assuming that parsimony excludes parental infanticide through eviction. ... 11.05608.x

Brood reduction in birds: Selection for fratricide, infanticide and suicide?
Raymond J. O'Connor
Abstract: Kin selection and inclusive fitness concepts are used to formulate a general theory accounting for the phenomenon of brood reduction in birds. The theory shows that as starvation mortality increases, selection favours at first fratricide, then fratricide plus infanticide, and finally fratricide, infanticide and suicide (by the nestling with the shortest life expectancy). A theoretical treatment of the alternative option, food sharing accompanied by concomitant reduction in growth rate, shows the latter to be ineffective when nest predation is high. Brood reduction is not limited in this manner. The theory allows several testable predictions about the incidence of starvation, starvation mortality, and sibling aggression, as well as their brood-size dependence and timing. These predictions are largely supported by the available evidence. ... 7278900088

Siblicide, Parental Infanticide, and Cannibalism at a Northern Goshawk Nest 2017
Stephen B. Lewis
Asynchronous hatching in birds provides a density-dependent system for maximizing parental reproductive success (Lack 1947, Mock 1984, Mock and Parker 1997). This mechanism allows adjustment to food shortages during the nestling season that cannot be predicted earlier, during egg-laying and incubation (Mock and Schwagmeyer 2009). Evidence of this has been found throughout the avian world and it usually manifests in some form of infanticide (i.e., killing of dependent young by conspecifics; Hrdy 1979, Mock 1984, Morandini and Ferrer 2014). Kin infanticide can occur via siblicide, resulting from overt aggression of siblings, or parental infanticide, resulting from overt aggression of a parent (Hrdy 1979, Mock 1984, Franke et al. 2013). Explanations for this behavior are often linked to a limiting resource, usually food (Hrdy 1979, Newton 1979). ... 22.1.short

More Than Kin and Less Than Kind: The Evolution of Family Conflict (BOOK)
Douglas W. Mock
Harvard University Press, 2004

Sibling rivalry and intergenerational conflict are not limited to human beings. Among seals and piglets, storks and burying beetles, in bird nests and beehives, from apples to humans, family conflicts can be deadly serious, determining who will survive and who will perish. When offspring compete for scarce resources, sibling rivalry kicks in automatically. Parents sometime play favorites or even kill their young. In More Than Kin and Less Than Kind, Douglas Mock tells us what scientists have discovered about this disturbing side of family dynamics in the natural world.
Natural selection operates primarily for the benefit of individuals (and their genes). Thus a family member may profit directly, by producing its own offspring, or indirectly, by helping close kin to reproduce. Much of the biology of family behavior rests on a simple mathematical relationship called Hamilton's rule, which links the benefits and costs of seemingly altruistic or selfish behavior to the degree of relatedness between individuals.
Blending natural history and theoretical biology, Mock shows how Hamilton's rule illuminates the study of family strife by throwing a spotlight on the two powerful forces — cooperation and competition — that shape all interaction in the family arena. In More Than Kin and Less Than Kind, he offers a rare perspective on the family as testing ground for the evolutionary limits of selfishness. When budgets are tight, close kin are often deadly rivals.
On Black Storks in that book:
"... I want to close these accounts of parental infanticide with a point about the way many such phenomena ever come to light. Much of what we now find comprehensible was not even imaginable just a few decades ago. Science proceeds in fits and starts, sometimes with a new technique that allows us to measure something previously out of our reach (such as relatedness), sometimes with fresh thinking and an argument that makes so much sense that it inspires us to look at things differently. And sometimes it is simply that the old explanations come to be at odds with the accumulated facts. A topic like parental infanticide is greeted at first with a wall of denial. Being both rare in most animal populations and viscerally abhorrent to human observers, it is likely to be underreported when first noticed. The initial reaction is to assume it is unrepresentative, a trivial pathology. I became interested in the problem of underreporting when an ornithological journal editor contacted me several years ago to ask if I would take a look at a manuscript, with photographs, that described a single incident of parental infanticide in a large European bird, the black stork. The evidence was very straightforward and highly suggestive. Two Pol-ish brothers, Grzegorz and Tomasz Klosowslci,27 excellent nature photographers, were observing a brood of five nestlings from a blind. A visiting parent had just fed the brood on regurgitated fish and rested for twenty minutes, when it suddenly seized the smallest chick by the head and threw it over the rim. The chick landed on the ground ten meters below and died immediately. Not a lot can be inferred from an anecdote like this. The attacking adult was not individually banded or identified by sex. The case for it being the victim's parent is thus circumstantial, based on the fact that black storks nest in considerable isolation deep in the forest (averaging more than two miles between nests). And the victim had just eaten food delivered by the killer. It seems highly improbable that a strange adult would fly a great distance and then feed the family before committing an anonymous infanticide. What I find so interesting about the incident is that the Klosowski brothers probably would never have reported it at all if the biology of infanticide had not become scientifically acceptable. As it was, they took the photographs on 18 June 1978 but did not publish them until encouraged to do so twenty-four years later. ..."

Infanticide (zoology)
In animals, infanticide involves the killing of young offspring by a mature animal of the same species, and is studied in zoology, specifically in the field of ethology. Ovicide is the analogous destruction of eggs. The practice has been observed in many species throughout the animal kingdom, especially primates (primate infanticide). These include microscopic rotifers, insects, fish, amphibians, birds and mammals. Infanticide can be practised by both males and females.

Adaptive secondary sex ratio adjustments via sex-specific infanticide in a bird. 2011
Heinsohn R, Langmore NE, Cockburn A, Kokko H.
Infanticide is easiest to understand when it involves killing the offspring of others, but a parent may also kill its own offspring if the sacrifice of currently dependent young leads to higher survival of brood mates or an improvement in the parent's likely future reproduction. However, sex-specific infanticide by parents of their own offspring, although occurring in some human societies, is rare across species. Its rarity may be because killing one sex combines wasted parental effort with consequent biases in population sex ratios that are detrimental for the fitness of the overproduced sex. We show that killing male offspring can be advantageous to Eclectus parrot (Eclectus roratus) mothers even though frequency-dependent selection then elevates the reproductive value of sons above that of daughters. In poorer-quality nest hollows, broods with a single female nestling had higher reproductive value than broods in which the female had a younger brother. Our data demonstrate frequent targeted removal of male nestlings within 3 days of hatching in these specific brood types and nesting conditions. The ability of Eclectus parrots to perceive the sex of their offspring relatively early may favour decisions to kill one sex before further investment in parental care.
full text: ... 3B07B32649

Infanticide by male house sparrows: gaining time or manipulating females?
Jose ́ P. Veiga
The killing of genetically unrelated young by males has been viewed as a strategy that forces victimized females to advance the onset of their next fertile period, thus infanticidal males gain a time advantage that may be crucial to maximize reproductive success. Among females that may raise several broods in a year, a failure occurring relatively earlier in the time-course of the previous breeding attempt may result in an increased investment in the next breeding attempt. This female strategy may be exploited by males in their own interest, and may strongly select for male infanticidal behaviour. I demonstrate that, in the house sparrow, females mated with infanticidal males relaid earlier, initiated more breeding attempts and fledged more offspring than females mated with non-infanticidal males. These results suggest that both the time saving and the manipulation of female investment are independent mechanisms conferring advantages that may have selected for male infanticide in the studied population. ... 952645.pdf

Unfit mothers? Maternal infanticide in royal penguins
St. Clair, Colleen & Waas, Joseph & Clair, Robert & Boag, Peter. (1995)
Crested penguins (genus Eudyptes) have a remarkable brood reduction system in which the first of two eggs laid is much smaller than the second and frequently disappears from the nest. The causes of this mortality are uncertain. In royal penguins, E. schlegeli, 70 of 84 pairs lost their first egg during the 4-day interval before the second was laid, and in 15 of 22 observed losses, mothers actively ejected their own eggs from the nest. Most first-egg losses (57%) occurred within a day prior to the appearance of the second egg. Parental ejection in royal penguins was not associated with high rates of extra-pair parentage: DNA fingerprinting of 13 two-chick families detected only one individual that was unrelated to its putative father. A manipulation experiment, intended to assess the viability and insurance value of first eggs, yielded equivocal results. The hatching success of first eggs, which were temporarily removed and then substituted for second eggs, was only half that of second eggs that were not removed (48% versus 93%, N=89), but apparent viability differences due to egg-type may have been confounded by delayed incubation and additional handling. None the less, the apparent reproductive value of first eggs was low; only one of 137 unmanipulated first eggs hatched. Some testable hypotheses are suggested for the evolution of ejection behaviour in Eudyptes. ... 1&type=pdf

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Re: What We Know About Black Storks

Posted: August 13th, 2019, 1:05 am
by Ari19
Nest trees - a limiting factor
for the Black Stork (Ciconia nigra) population in Estonia
Asko LÕHMUS & Urmas SELLIS ... 1-4_84.pdf

:laugh: Do you see the authors?

Re: What We Know About Black Storks

Posted: August 13th, 2019, 1:20 am
by Ari19
Factors affecting the nest site selection of the black stork, Ciconia nigra in the Dadia-Lefkimi-Soufli National Park, north-eastern Greece ... ion_detail

Anne7, :hi: are you looking for info and articles such as these? Let me know.
If these scientific articles are appropriate, I can try to find more over time.

Re: What We Know About Black Storks

Posted: August 13th, 2019, 1:41 am
by Jo UK
Ari, thank you so much for your contributions. At last, someone else to do some of the work!. Your articles are just what is needed. And yes, I see the name of an author who is well known to us.
I do hope that other members will visit this topic and post other items, too.

Re: What We Know About Black Storks

Posted: August 13th, 2019, 6:43 am
by Liz01
Liz01 wrote: ↑August 8th, 2018, 5:08 am

Email from Maris Strazds

Start of migration. Departure from nest does NOT mean immediate start of migration. Some birds do but many hang around for quite some time. This can be identified for tagged bird ONLY, all other „data” are speculations. I do not know what the english version of Vikipedia (in general poor source concerning BS) quotes but very likely those can be birds from western flyway – France and Belgium. Even if the figures are correct from the right sources, those birds are very different from eastern flyers (like ours or EE storks are), so cannot be used as a reference concerning thoughts „when will these juveniles start migration?”. Czech birds fly both ways so those data must be devided per flyway before quoting. Another important aspect is extra 1000-1500 km birds from LV and EE shall fly. It adds some time that they require to make it happen.

Data (unpublised so far) from 22 LV storklets that started migration at all (from 27 tagged), the mean age of start of migration is at least 89.7 days, min. 73.4, max 142.2 days. Of those 5 birds that reached age of 1 year, mean age is 90.5 days (Mellene – 92.5, Kate – 85.4, Sarma – 115.2, Raitis – 83.0, Mare – 76.4).

Re: What We Know About Black Storks

Posted: August 13th, 2019, 11:53 am
by Anne7
Black Stork Nestlings.
Diet, gender ratio, body condition...

Age estimation of black stork (Ciconia nigra) nestlings from wing, bill, head, and tarsus lengths at the time of ringing
Abstract: Black stork nestlings were measured (wing, bill, head, and tarsus lengths) at weekly intervals in central Poland in 2012, 2014, and 2015. The aim of the study was to provide growth equations based on nestling measurements to allow age estimation of black stork nestlings. The hatching hour and date of nestlings in five nests were determined using trail cameras. The age of the measured nestlings ranged from 18 to 53 days. Wing, bill, and head lengths showed linear growth, while tarsus growth was only linear for nestlings not exceeding 35 days old. Within the age range studied, wing length grew 9.6 mm per day, head length grew 2.3 mm per day, and bill length grew 1.8 mm per day. The study provides the first growth parameters for the black stork. ... 702-42.pdf

The diet of young's and feeding places of Black Storks Ciconia nigra in Gemenc (Hungary)
Enikő Anna TAMÁS & Béla KALOCSA
AbstractWe have been carrying out investigations of the feeding of Black Storks Ciconia nigra in the Gemenc area since 1996. We have collected data about the species and quantity of prey found near nests and thrown up by young during ringing; furthermore, we regularly observe Black Storks at feeding places as well. Based on these eight years’ data, the food and feeding place preference of the Black Stork can be determined (for this habitat, or for this type of habitat). Main food of the Black Stork is fish, whereas the most important feed-ing grounds are temporary shallow floodplain waterbodies. ... Gemenc.pdf

Food Provisioning and Nestling Diet of the Black Stork in the Czech Republic
Radek Hampl, Stanislav Bureš, Peter Baláž, Miroslav Bobek, František Pojer
Abstract: The food composition, prey size, quantity of prey, feeding frequency and diurnal pattern in the feeding frequency of chicks of Black Stork (Ciconia nigra) were studied in six nests in the Czech Republic during the breeding seasons 1998-2003. Video cameras were used to record prey brought to the nests. Regurgitations and pellets were also analyzed. In total, 474 prey items were collected. Aquatic animals, mainly fish, prevailed in the nestlings’ diet. Six species of fish, undetermined frogs and snakes, two mammal species and eight insect species were found. Adults provisioned their young nestlings with smaller fish. The length of fish and total mass of consumed prey significantly increased with nestling age. No relationship between chick age and feeding rate was found. In total, each chick consumed 14-20 kg of food up to fledging. ... h_Republic

Diet of the Black Stork in the Czech Republic
Nature Conservation Agency of the Czech Republic, Kaplanova 1931/1, CZ 148 00 Prague, Czech Republic

2nd Records on Black Stork young food found on nests in Central and West Bohemia in 1994-2012 confirm the dominancy of fish. The food analysed was mostly that thrown out by nestlings during their ringing. Fish significantly dominated in the Black Stork nestling diet (89.4 % by numbers), followed by lampreys (4.9 %) and amphibians (2.8 %). Mammals (1.21 %), reptiles (0.4 %) and invertebrates (1.2 %) were less important. The freshwater Brown Trout Salmo trutta was the most abundant prey (35.7 %), while the Common Roach Rutilus rutilus, Common Carp Cyprinus carpio, European Perch Perca fluviatilis and the Tench Tinca tinca were preyed less frequently. The fish/Brown Trout captured mean size was 17.29 cm, while the mean weight was found to be 68.1 g. ... t-Book.pdf

Younger, weaker white stork (Ciconia ciconia) nestlings become the best breeders
José I. Aguirre and Pablo Vergara
Background: The literature suggests that migratory bird individuals that hatch first are more
fit than their siblings.
Hypothesis: Older siblings in better physical condition will produce more chicks as breeders.
Time and location: A population of white storks nesting in the province of Madrid (central
Spain) was monitored annually between 1999 and 2004.
Methods: Hatching order, weight of hatchlings and nestlings, and date of return were
recorded and correlated with subsequent fitness and measured as breeding outcome (binomial,
failed or successful nests) and productivity (number of nestlings produced).
Conclusions: Contrary to expectations based on their higher nestling weight, and to our
hypothesis, first-hatched siblings returned later to the breeding grounds, were less successful,
and produced fewer chicks than the rest of the brood. ... _9_355.pdf

Contributed by Liz01
Brood sex ratio and nestling physiological condition as indicators of the influence of weather conditions on breeding black storks Ciconia nigra
Maciej Kamińskia, Jerzy Bańburab, Bartosz Janica, Katrin Kaldmac, Annika Konovalovc, Lidia Marszała, Piotr Miniasd, Ülo Välic, Piotr Zielińskia
• The paper examines the influence of weather on Black Stork nestlings sex ratio.
• Temperatures in the pre-breeding period negatively correlate with nestling male ratio.
• Rainfalls in the hatching period negatively correlate with nestling male ratio.
• Delayed broods have lower nestling male ratio.
• Male nestlings have poorer body condition.
Abstract: In species with sexual dimorphism, raising female or male offspring may be associated with different costs and benefits, resulting in a skewed nestling sex ratio. We examined the influence of weather conditions, hatching date and brood size on nestling sex ratio in the black stork Ciconia nigra. We used molecular methods to determine the sex of 284 nestlings. Samples were collected during a 12-years study in central Poland. The overall nestling sex ratio was skewed towards females (61%), which are smaller, and presumably easier to raise than males. Delayed hatching date significantly increased the proportion of female nestlings. Warmer temperatures in the pre-breeding season were correlated with lower proportions of males. This is probably mediated by the influence of weather on water levels in black stork foraging sites. The second most important weather trait was total rainfall in May, the month in which the majority of nestlings hatch. Total May rainfall was negatively correlated with the percentage of male offspring. We used blood haemoglobin concentration as an indicator of body condition in a subsample of 122 nestlings. The males from the study population had lower blood haemoglobin concentrations, indicating their poorer body condition and supporting the hypothesis that they are the more vulnerable sex. We also observed that blood haemoglobin concentration of nestlings is lower in late broods. Deteriorating body condition of late offspring can explain the observed increase in female nestling proportions in delayed broods. ... 0X19303279

Growth of Young Black Stork in the Czech Republic
1 Nature Conservation Agency of the Czech Republic, Kaplanova 1931/1, CZ 148 00 Prague, Czech Republic
2 Moskevska 1446/61, CZ 101 00 Prague

In 1994-2012, biometric data of 576 young on nests (nestlings/pulli) were gathered during Black Stork´s ringing activity in the Czech Republic, particularly in an area located west and southwest of Prague. In total, 1,325 data on three measurements, namely wing, beak and tarsometatarsus lengths were collected. From the data raised during Black Stork young rearing at the Prague Zoo the growth curve was constructed and regression lines were calculated describing the linear relationship between wing, beak and tarsometatarsus lengths and nestling age throughout the brooding period. Wing and beak growth has not been finished at the time were young is ringed at the nest and has further been continuing, while tarsometatarsus growth is finished at that period, reaching the size known in adults.
Daily growth rates in the period of linear growth are 9.1 mm for wing, 1.9 mm for beak and 3.6 mm for tarsometatarsus. From the data gathered, the date reaching the wing length having been determined in advance at 400 mm, i.e. at the age of 50 days was computed for each young. Thus, the baseline age value distribution (i.e., the particular days = date) was analysed in the respective years. The timing of breeding in the respective years was tested against shifting in the starting nesting in 1994-2012: it was confirmed that the nesting has started 4 days earlier in the course of the above period, possibly caused by step-by-step climate change.
Ring recovery data obtained for the young studied (in total, 83 individuals) in relation to their size (i.e., to their age) at the nest. It was found that the oldest and biggest young, i.e. “first-born”) predominate among the recovered birds, assuming that they better survive (the latter are being better genetically fitted for survival, displaying better fitness).
For determining the age in young on the nest based on lessons learnt, it is recommended when determining the nestling age to measure the total wing size, the beak size respectively, the latter being the supplementary information for checking the calculation. The one-day margin for error corresponds with the accuracy/exactness of measurements and with the daily growth rate in both the parameters studied. ... t-Book.pdf

What Makes a Successful Migrant?
Lessons from a Five Year Tracking Project of a Long Distance Migratory Species

Maris STRAZDS1, Wolfgang FIEDLER2 and Hans-Günther BAUER2
1 Laboratory of Ornithology, Institute of Biology, University of Latvia, Latvia
2 Max Planck Institute of Ornithology, Germany

In 2013-2017 we have tracked 27 juvenile Black Storks Ciconia nigra with GSM transmitters from Latvia (NE Europe). Contrary to many migratory species, Black Stork is a solitary traveller. Juvenile birds during their first migration from northern Europe to trans-Saharan Africa must rely upon the resources they received at the nesting site and experience they gain during migration. Our data suggest that two domestic factors might have a significant impact on their migratory success - body weight and longevity of stay in nest. Early departure from the nest is strongly associated with migratory failure, so highlighting potential negative impact of late season disturbances in the vicinity of nests. Most successful birds left their nests late and started the southward migration straight from the nest. Typical migration consists of comparatively short bursts of flight days interspersed with longish foraging stops along their long journey - the longest one from our data exceeding 10,500 km one way. The most important factor affecting success of travel appears to be longevity of stay at the most important foraging stops rather than number of sites they explore. Those birds that made a backward migration visited most of the sites they had explored earlier, however, with different travel routes between the stops. None of one-year old birds did return to breeding grounds. Instead, they spent their second summer in suitable territories 1,000 – 2,000 km from their nests (in Turkey, Romania, Moldova, Ukraine). In all but one of those territories checked we found many more resting storks, mostly of similar age, along with other species of wading birds. In most cases these sites were not known for local ornithologists / conservationists as important bird gatherings. One of such locations in Romania may potentially be the most important summer roost of 2nd calendar year Black Storks from Eastern Europe, thus deserving high degree of attention from the conservation viewpoint. We discuss also other factors potentially affecting migration success, such as late vs. early brooding, weather conditions, role of predators and learning "en route". ... t-Book.pdf

Intra-Seasonal and Brood-Size Dependent Variation in the Diet of Black Stork (Ciconia nigra) Nestlings
Maciej Kamiński, Jerzy Bańbura, Bartosz Janic, Lidia Marszał, Piotr Minias, and Piotr Zieliński
Abstract: Nestling diet and parental provisioning rate are important determinants of reproductive success and future offspring performance in birds. The diet of Black Stork (Ciconia nigra) nestlings was characterized and tested for intra-seasonal and brood-size dependent variation in the type and mass of prey provisioned to the brood. Data were collected on 576 prey items from 45 Black Stork broods in central Poland during 2005–2016. Black Stork nestlings were provisioned almost exclusively with fish and amphibians; the proportion of invertebrates in their diet was marginal. Fish were a dominant component of nestling diet, comprising up to 65% of prey items and over 85% of total prey mass. Common spadefoot tadpoles (Pelobates fuscus), weatherfish (Misgurnus fossilis) and Prussian carp (Carassius gibelio) were among the most abundant prey. Black Storks foraged on relatively small prey, with an average length of 101.4 ± 1.5 mm (n = 576) and an average mass of 13.8 ± 1.0 g (n = 550). Larger broods were significantly more often fed with amphibians and with lighter prey. As the season progressed, the probability of preying on amphibians increased. This study provides evidence for Black Stork provisioning effort optimization mediated by selection of smaller, but easier to catch and handle prey, such as common spadefoot tadpoles. ... 0306.short

Spatio-temporal variation in nestling sex ratio among the Black Stork Ciconia nigra populations across Europe
Annika Konovalov, Katrin Kaldma, Andriy Bokotey, Paul Brossault, Frederic Chapalain, Marina Dmitrenok, Natalie Dzyubenko, Urmas Sellis, Māris Strazds, Luc Strenna, Rimgaudas Treinys, Piotr Zielinski, Ülo Väli
Abstract: Sex ratio is an indicator of population health as unexpected biases may indicate potential threats. We studied nestling sex ratio in Black Stork Ciconia nigra populations in order to check potential biases and differences along east–west and north–south gradient across its distribution range in Europe. We also studied variation between years, and checked potential correlations with weather variables. The overall sex ratio of nestlings in Europe was nearly equal with a non-significant deficiency (47.1 %) of males, the larger sex. Although yearly fluctuations in sex ratio were detected, no significant effect of the year alone was found, only simultaneously with population and brood size. There was a tendency to have a higher proportion of female nestlings in larger broods, but the pattern was probably scattered by the effect of reduction of largest broods. Compared to Western and Eastern Europe, a significant deficiency of male nestlings was found in Central Europe (Poland), whereas no differences were found along the north–south gradient. We did not find any effect of temperature, but rainfall during the incubation period was negatively correlated with the proportion of male nestlings in Central (Poland) and Western Europe (France) whereas in North-Eastern Europe (Latvia) the same effect of the precipitation in pre-breeding period was found. ... Europe.pdf

Molecular sexing of the Black Stork Ciconia nigra: sex ratios in the Portuguese population
Margarida FERNANDES, Carla BORGES, Fernanda SIMÕES, José Manuel CABALLERO, Carlos PACHECO & Cláudia FRANCO;
Abstract: We sexed 125 chicks of black stork ringed between 2003 and 2005 in Portugal. We use a combination of molecular methods which effectively determine sex in this species. Analysis was done mainly using feather samples, applying a non invasive approach to a threatened population. Sex ratios and female proportion within broods were calculated. An excess of females was observed during the years studied, and globally, the deviation from parity was statistically significant. This result needs to be confirmed and related to changes in habitat quality. The sex ratio of black stork populations should be monitored in the long term as they may be an important source of information for monitoring ecological stress. This is the first assessment of sex in a wild population in Portugal. ... lation.pdf

Artificial Incubation and Nestling Raising of Black Stork F_2
Liu Shuhua Bai Xiaojie Liang Weifeng (Qiqihar Longsha Park, Qiqihar 161005, China)
During the experiment of the artificial incubation of black stork (Ciconia nigra) from 2001 to 2004 in Longsha Park of Qiqihar city, the incubation temperatore and relative humidity were receded and the physiological indices, such as body weight, length of body, rostra, wing and tail, of 5F2 nestlings, hatched by artificial incabation, were measured, in order to investigate the growth progress of the nestlings. Results indicated that the temperature of egg incubation in the earlier period (1-29d) was 37.7℃ and the relative humidity was 55%. In the later period, (29-31d), the temperature of breaking the egg shell was 37℃ and the relative humidity was 65%. The temperature of the nestling incubator was 37℃ in the earlier 7 days, the gradually decreased for 0.5℃ per day; the relative humidity maintained at 55%. After 20 days, the nestling can be grown under room temperature. The growth curve of physiological indices of black stork F2 nestlings can be simulated by Logistic ... 506019.htm

Kind to kin: weak interference competition among white stork Ciconia ciconia broodmates
José María Romero and Tomás Redondo
Altricial nestlings in structured families show a diverse array of behavioural mechanisms to compete for food, ranging from signalling scrambles to aggressive interference. Rates of filial infanticide are moderately high in white storks. It has been hypothesized that this unusual behaviour is an adaptive parental response to the absence of efficient mechanisms of brood reduction (aggression or direct physical interference) by nestlings. To test this latter assumption, we analyzed video recordings of 41 complete feeding episodes at 32 broods during the first half of the nestling period, when nestlings complete 90% of growth and chick mortality and size asymmetries are highest. Parents delivered food to all nestlings simultaneously by regurgitating on the nest floor. No direct (bill to bill) feeding was recorded. Senior nestlings were never observed to limit their junior nestlings from eating food, either by aggression or physical interference. Experimental feeding tests revealed that heavier nestlings handled prey items more efficiently and ate food at a higher speed. The high degree of tolerance shown by senior nestlings is unusual among birds with similar ecological and phylogenetic affinities, such as herons. Tolerance by seniors cannot be easily explained by the absence of parental favouritism or proximate factors known to affect the occurrence of sibling aggression in other species (rate of food transfer, brood size, hatching asynchrony or length of nestling period). ... /Tomás.pdf

Posted by Urmas: viewtopic.php?p=488921#p488921
Chicks age at first flights depends on food abundance in previous stages in development. If we go back in years 2007-2011 then we see difference of first flight in weeks in the same nest. There may be different parents, but for sure the years are different for availability of food by parents. Our storklets were well fed by ringing time. According our Latvian colleague Maris Strazds better results are in surviving of the chicks which spend longer time in nest after fledging, means they return to the nest and step by step get independent, but are still getting food from parents in nest. Disturbance, what leads flying off the nest is negative for further survival. Therefore we are very much cautious in visiting the nests at late stage of breeding. Lets hope Karl will follow that hint to spread his genes firmly... Absence of Kati is not good in that context, though.

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Re: What We Know About Black Storks

Posted: August 13th, 2019, 11:57 am
by Ari19
Anne7 wrote:
August 13th, 2019, 11:53 am
Thank you, Ari! :hi: I'm glad you help!
Yes, this is the type of information that we want to collect here. All possible scientific articles about the Black Stork, good online info (eg from Audubon, but of course also from other good sources), all valuable information that has already appeared on the forum in recent years, etc ... For the time being, everything is collected randomly on this topic. We intend to organize everything later, by theme.

I personally find it useful if the abstract of a scientific article is copied under the link. This allows people to see at a glance what is being studied and discussed.

Liz, thank you too! Interesting info! :wave:
Sounds great, Anne7! I (and I’m sure other members too) will try to find more info and add it here. Thanks for the note on the abstracts, I will make sure to add in the future.
:nod: :wave:

Re: What We Know About Black Storks

Posted: August 13th, 2019, 6:48 pm
by Liz01
Anne :wave:
I can not really help right now. all interesting links and files are on my PC. I'm on vacation with a laptop.
I would have to read the threads :slap: .. that's too much work and very ineffective. so I wait until after my vacation.

Re: What We Know About Black Storks

Posted: August 13th, 2019, 10:07 pm
by Anne7
Depredation of Black Stork Nestlings and Eggs

The First Documented Case of Northern Goshawk Accipiter gentilis Predation on Black Stork Ciconia nigra Nestlings
Bartosz JANIC1, Maciej KAMIŃSKI1, Dariusz PIENIAK2, Michał STRAWIAK3 and Piotr ZIELIŃSKI1
1 Department of Ecology and Vertebrate Zoology, Faculty of Biology and Environmental Protection, University of Lodz, Banacha 12/16; 90-237 Łódź, Poland.
2 Institute of Forest Sciences, University of Lodz Branch in Tomaszow Mazowiecki, Konstytucji 3 Maja, 97-200 Tomaszów Mazowiecki, Poland.
3 Leśny Zakład Doświadczalny SGGW w Rogowie, ul. Akademicka 20, 95-063 Rogów, Poland.

In 2016 and 2017 five instances of the Northern Goshawk Accipiter gentilis depredating Black Stork Ciconia nigra nestlings were observed using web camera installed at a Black Stork nest in central Poland. In 2016 the Goshawk depredated whole brood of three Black Stork nestlings. The nestlings’ ages at the time of the attack were 23, 21 and 23 days. In 2017, at the same nest, the Goshawk partially depredated the brood, removing two (age 21 and 24 days) out of the four nestlings. In 2018, in other nest with web camera, the Goshawk depredated whole brood of five nestlings (age 26, 29, 35, 37 and 38 days). It is suggested that the impact of the Goshawk predation on Black Stork broods is much stronger than previously thought. This study was a part of a Black Stork joint project of the Regional Directorate of State Forests in Lodz, the Eagle Conservation Committee and the University of Lodz (2016-2017) and the Regional Directorate of State Forests in Lodz and the University of Lodz in 2018. ... t-Book.pdf

New Data on Black Stork Nest Predators in Latvia
Māris STRAZDS1 and Linda OSE 1,2
1 Laboratory of Ornithology, Institute of Biology, University of Latvia
2 Faculty of Geography and Earth sciences, University of Latvia

We used trail cameras to collect more accurate data on Black Stork phenology, to collect ring recoveries of adult birds and to improve knowledge on the behaviour of Black Storks in Latvia since 2011. The total amount of data to be used for analyses comprises 9,351 camera days, with 5,218 days of stork presence, 1,141,248 pictures in total. These data among other things also document numerous visits of predators and show some depredation cases in detail. The new data have changed our understanding of the significance of some of the known predator species, namely Goshawk Accipiter gentilis depredation is far more significant than was suspected earlier. Another important new finding is that many depredation cases are partial. This leaves some nests "depredated" but successful at the same time. Our data show that depredation during egg period is very strongly underrated and that partial depredation is most frequently not registered at all. We discuss the differences in patterns of attacks of various predator species and difficulties in discovering true causes of egg and/or chick loss during the breeding season. ... t-Book.pdf

Battle between a Pine Marten and a Black stork on a BS nest in Belgium VIDEO


Re: What We Know About Black Storks

Posted: August 14th, 2019, 3:27 pm
by Anne7
Flight, Feathers and Moult


Posted here: viewtopic.php?p=618022#p618022
Flight characteristics and atmospheric conditions
Mean flight altitude and flight speed values for the entire migration of the three birds tracked with GPS PTT were found to be 495 + 50 m above surface level and 33.0 + 1.7 km h, respectively. Assuming a similar flight altitude for the remaining birds tracked with ARGOS PTT, we selected wind speed and direction at an altitude of 110 m (the closest to 495 m of the altitudinal meteorological measurements available) and related those to flight speed and azimuth for all birds.
We analysed flight speed per hour and found that the lowest and highest values occurred, respectively, between 6.00 and 9.00 h and between 11.00 and 16.00 h
A figure showing flight altitudes and speed of Black Storks in a small case study:
Image ... .2010.0422

Contributed by Liz01
Storks on the wing
Scientists can predict which (White) storks will migrate to Africa in autumn and which will remain in Europe

For little Louis, it is the most exciting day of his life: just six or seven weeks ago, the young stork came into the world on a birch tree in Radolfzell on Lake Constance. Up to this day in June 2014, he has only known his parents and three siblings. But suddenly strange beings have appeared at the nest and are holding the four small white storks captive. They are Andrea Flack and Wolfgang Fiedler of the Max Planck Institute for Ornithology and the University of Konstanz. In the coming years, the scientists will learn from Louis and other young storks that, on their migrations south, storks follow other storks who are particularly good at exploiting thermals, allowing them to flap their wings as little as possible as they fly. The efficient fliers migrate to West Africa, while the others spend the winter in southern Europe. From their data, the researchers can tell which storks will fly where just ten minutes after the birds take off.
Searching for thermals

Travelling storks

Thermal soaring flight of birds and UAVs
Zsuzsa Ákos, Máté Nagy, Severin Leven and Tamás Vicsek
Abstract. Thermal soaring saves much energy, but flying large distances in this form
represents a great challenge for birds, people and Unmanned Aerial Vehicles (UAVs).
The solution is to make use of so-called thermals, which are localized, warmer regions in
the atmosphere moving upwards with a speed exceeding the descent rate of birds and
planes. Saving energy by exploiting the environment more efficiently is an important
possibility for autonomous UAVs as well. Successful control strategies have been
developed recently for UAVs in simulations and in real applications. This paper first
presents an overview of our knowledge of the soaring flight and strategy of birds,
followed by a discussion of control strategies that have been developed for soaring UAVs
both in simulations and applications on real platforms. To improve the accuracy of
simulation of thermal exploitation strategies we propose a method to take into account
the effect of turbulence. Finally, we propose a new GPS independent control strategy for
exploiting thermal updraft.

Lift (soaring)
Lift is a meteorological phenomenon used as an energy source by soaring aircraft and soaring birds. The most common human application of lift is in sport and recreation. The three air sports that use soaring flight are: gliding, hang gliding and paragliding.
Energy can be gained by using rising air from four sources:
• Thermals (where air rises due to heat),
• Ridge lift, where air is forced upwards by a slope,
• Wave lift, where a mountain produces a standing wave,
• Convergence, where two air masses meet

Physiological, aerodynamic and geometric constraints of flapping account for bird gaits, and bounding and flap-gliding flight strategies
Aerodynamically economical flight is steady and level. The high-amplitude flapping and bounding flight style of many small birds departs considerably from any aerodynamic or purely mechanical optimum. Further, many large birds adopt a flap-glide flight style in cruising flight which is not consistent with purely aerodynamic economy. Here, an account is made for such strategies by noting a well-described, general, physiological cost parameter of muscle: the cost of activation. Small birds, with brief downstrokes, experience disproportionately high costs due to muscle activation for power during contraction as opposed to work. Bounding flight may be an adaptation to modulate mean aerodynamic force production in response to (1) physiological pressure to extend the duration of downstroke to reduce power demands during contraction; (2) the prevention of a low-speed downstroke due to the geometric constraints of producing thrust; (3) an aerodynamic cost to flapping with very low lift coefficients. In contrast, flap-gliding birds, which tend to be larger, adopt a strategy that reduces the physiological cost of work due both to activation and contraction efficiency. Flap-gliding allows, despite constraints to modulation of aerodynamic force lever-arm, (1) adoption of moderately large wing-stroke amplitudes to achieve suitable muscle strains, thereby reducing the activation costs for work; (2) reasonably quick downstrokes, enabling muscle contraction at efficient velocities, while being (3) prevented from very slow weight-supporting upstrokes due to the cost of performing ‘negative’ muscle work.


Contributed by Liz01
The feathers of the Black stork (Ciconia nigra)
The hand-swings of the black stork are colored deep black-brown with a coppery glow and a full black keel. The inner flag is hardly brightened and the feather base is only slightly grayish lined. The arm swings have the same color and are rectangular in shape. The shield feathers are slightly enlarged. The control feathers are colored deep black - usually even darker than the wings - and only the outer control feathers have a slight whitening of the inner lug. The hand swing H6 to H10 (if this sometimes even vaguely in the lower part is wider) are partially constricted in the outer flag. H11 is completely narrowed. The inner lobes from H7 to H11 are also narrowed. In the habitat of the black stork, it can sometimes come to confusion with feathers of the white stork or the European crane. The white stork has a slightly more brownish inner flag, a clear white inner flag base and a whitish outer flag tire. The wings of the crane are generally lighter, so grayish and the inner flag is noticeably brightened. In addition, the feathers of white stork and crane are much duller, so have no metallic shine.

Moult of the Black Stork

Wing and tail moult in the Black Stork Ciconia nigra (in German)
Max Bloesch, Wendla Boettcher-Streim and Maurice Dizerens
Wing and tail moult of a first-year male Black Stork was studied in captivity over eight years. The scheme of moult, growth rate, growing period, frequency of moult of individual feathers and the annual amount of moult were recorded. Moult proceeded serially as follows: descendant from the innermost primary (H1), ascendant from the outermost secondary (A 1) and convergent from A 5 and A20, respectively. Tail feathers were moulted serially divergent, from the center (Si) outwards. These patterns were more or less symmetrical. The first moult started at the end of the first year of life (end of April/beginning of May). On average 12 of the 22 primaries, 22 of the 40 secondaries (excluding A21 which was moulted irregularly) and 6 of the 12 tail feathers were moulted per year, equivalent to 55% of the feathers and 10,8 m of feather growth. Growth rates varied according to the position of the feathers, from 4,2 to 7,2 mm/day. It was highest in primaries. Feathers attained 90% of their final length in 34-54 days. They were, on average, fully grown after 50-55 days; growth to completion of the longest primaries lasted for up to 75 days. Cycles increased in length from 1-1,5 years to replace the first feather generation to 3,5 years for the second; the fourth generation was not yet complete after 4 years. Feathers were worn for 1-3 years, depending on the position and generation. A consequence of this scheme of moult is that the areas of growing feathers are more and more spread over the wing, avoiding larger gaps. Unlike in the White Stork, moulting continued throughout the winter until the fourth year of life, when it was interrupted during the period of spring migration of the Black Stork. After this age, presumably when reaching sexual maturity, moult was concentrated to the normal breeding period in summer. ... loesch.pdf

More information on Wings, Flight and Feathers (birds in general) » viewtopic.php?p=689187#p689187

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Re: What We Know About Black Storks

Posted: August 14th, 2019, 3:37 pm
by Anne7
Migration: Different Routes

African Odyssey project –
satellite tracking of black storks Ciconia nigra breeding at a migratory divide

Miroslav Bobek, Radek Hampl, Lubomır Peske, Frantisek Pojer, Jaroslav Simek and Stanislav Bures
Abstract: The African Odyssey project focuses on studying the migration of the black stork Ciconia nigra breeding at a migratory divide. In 1995–2001, a total of 18 black storks breeding in the Czech Republic were equipped with satellite (PTT) and VHF transmitters. Of them, 11 birds were tracked during at least one migration season and three birds were tracked repeatedly. The birds migrated either across western or eastern Europe to spend the winter in tropical west or east Africa, respectively. One of the juveniles made an intermediate route through Italy where it was shot during the first autumn migration. The mean distance of autumn migration was 6,227 km. The eastern route was significantly longer than the western one (7,000 km and 5,667 km respectively). Important stopover sites were discovered in Africa and Israel. Wintering areas were found from Mauritania and Sierra Leone in the west to Ethiopia and Central African Republic in the east and south. One of the storks migrating by the eastern migration route surprisingly reached western Africa. Birds that arrived early in the wintering areas stayed longer than those arriving later. On the average, birds migrating via the western route spent 37 d on migration compared to 80 d for birds migrating via the eastern route. The mean migration speed in the autumn was 126 km/d and the fastest stork flew 488 km/d when crossing the Sahara. The repeatedly tracked storks showed high winter site fidelity.

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Breeding and MIGRATION of the Black Stork (Ciconia nigra), with special regard to a Central European population and the impact of hydro-meteorological factors and wetland status
Tamás Enikő Anna; Doctoral (PhD) thesis, 2012
... Due to the general absence of thermals above the sea, the storks circumvent the Mediterranean Sea via southern Spain, close to Gibraltar or via Turkey and Israel (Bobek et al. 2008).
The numbers of Black Storks using the different migration routes are the result of summarizing the averages of the recent years' migration counts carried out in different locations. ...
... The exact delimitation of Black Storks' migratory divides are not known (Bobek et al. 2008). But current knowledge shows no evidence of geographical coincidence between the European and Asian, the European and African, and the African and Asian populations. As there is no proof of overlaps in wintering grounds, and migration routes seem to be much different, I could assume these three geographical parts of the range are isolated. ... ... sAllowed=y

Figure 21. Main migratory routes of European Black Storks, based on literature, satellite tracking, colour ring recoveries and migration counts, re-drawn by the author (Tamás Enikő Anna)

The Eastern Route

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Breeding and MIGRATION of the Black Stork (Ciconia nigra), with special regard to a Central European population and the impact of hydro-meteorological factors and wetland status
Black Storks breeding in north-eastern-Europe and western-Asia use the eastern shorelines of the Black Sea to migrate near the Caucasus through Turkey and Israel to Africa. Janssen et al (2004) reports that a high number of Black Storks can be observed using this route. It is supposed that a part of these birds come from the Baltic, another part from Russian and Ukrainian breeding grounds. ...
Black Storks often suspend their autumn migration for several days, even weeks, supposedly in case they find a suitable refuelling site. Identified (colour-ringed) Black Storks using stopover sites in Israel spent 9 days at the site on the average, with a maximum of 29 days (van den Bossche 1996). ...
On the Eastern route, according to the counts carried out in Israel between 1988 and 1995, the start of fall migration is at the beginning of August, and the end is at the end of November. The most Black Storks cross Israel in the second half of September and the first half of October (even a daily 1000 individuals, the maximum counted was 1821). Migration peaks of adults and young birds are not the same in Israel, as adults arrive sometimes even 2-3 weeks earlier (pers. comm. van den Bossche). ... sAllowed=y

Spring migration of the White Stork, Ciconia ciconia, and the Black Stork, Ciconia nigra, over the Bosphorus
Zeynel Arslangündoğdu, Cem Dalyan, Ergün Bacak, Ümit Yardım, Cemil Gezgin & Vedat Beşkardeş (2011)
Abstract: The spring migration of the White Stork (Ciconia ciconia (Linnaeus)) and the Black Stork (C. nigra (Linnaeus)) over the Bosphorus, one of the migration bottlenecks of the eastern European population, was studied in 2006, 2008, 2009 and 2010 at a ridge north of Sarıyer close to the Black Sea. The number of White Storks counted per season was up to 119,381 in 2008, but it was less than half of that in 2006 and 2009. These big fluctuations do not reflect population trends but are probably due to slight shifts in migration routes from year to year. The number of Black Storks varied between 1,118 in 2006 and 3,052 in 2008. The medians of spring migration were 6 April for White Storks and 17 April for Black Storks. ... ode=tzme20

Autumn migration of the White Stork, Ciconia ciconia, and the Black Stork, C. nigra, over the Bosphorus (Aves: Ciconiidae)
Zeynel Arslangündoğdu, Ergün Bacak, Vedat Beşkardeş, Cem Dalyan, Luke Smith, Margaret R. Payne & Ümit Yardım
Abstract: The Bosphorus is one of the main migration routes for soaring birds in Europe. Migrating White Storks and Black Storks have been counted at Büyük Çamlica hill in the four autumn seasons of 2006, 2007, 2008 and 2009 for 78 days each year. The numbers recorded are significantly lower than those counted in the1970’s, and it is discussed whether this decline could be related to a change in migration routes caused by an increase in the size of the urban area of the City of Istanbul. The population of Istanbul has increased from 3.0 million in 1970 to 13.2 million in 2010. ... 17.1305496

Colour rings on migrating Black Storks Ciconia nigra
Paweł T. Dolata, Bertrand Posse
Throughout Europe the Black Stork is a rare breeding bird, including in Eastern Europe (principally Poland) where the majority of the population is to be found. For this reason most birds follow the eastern migration route via the Dardanelles and the Bosphorus. Colour ringing in several European countries, starting in 1994, has considerably improved the readability of rings during the bird’s migration halts. This is helping to provide better information about the migration of this species and should lead to better protection of the species during this period of its life cycle. First results show that 20 % of Czech storks follow a western migration route via the Straits of Gibraltar and also that young storks from Poland also appear to follow this route. Observers are requested to keep their eyes open for coloured rings on Black Storks at their migration halts; some have already been seen in Switzerland and France. ... onia_nigra

The Western Route

Variable shifts in the autumn migration phenology of soaring birds in southern Spain 2016
Micah N. Scholer, Beatriz Martín, Miguel Ferrer, Alejandro Onrubia, Marc J. Bechard, Greg S. Kaltenecker & Jay D. Carlisle
While alteration of the migratory habits of birds is widely regarded as one of the most evident ecological effects of climate change, studies reporting shifts in migration phenology for long-lived, long-distance migrants have been few. Using time-series of count data collected in southern Spain during autumn migration,we examined the magnitude and direction of phenological shifts for six common species of soaring birds. Many current methods for investigating phenological change rely on continuous data sets; however, these data may be unavailable for a variety of reasons. We used a cross-correlation analysis, which allowed us to compare recent data on the timing of migration from 1999–2011 to a historic data set collected during 1976–1977. The direction of phenological shifts for autumn migration was species-specific. White Storks Ciconia ciconia and Black Kites Milvus migrans appeared to have delayed passage. Black Storks Ciconia nigra and European Honey Buzzards Pernis apivorus have advanced their migratory timing, and we found no clear phenological change for Short-toed Eagles Circaetus gallicus or Booted Eagles Hieraaetus pennatus. ... view-paper

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Breeding and MIGRATION of the Black Stork (Ciconia nigra), with special regard to a Central European population and the impact of hydro-meteorological factors and wetland status
Tamás Enikő Anna; Doctoral (PhD) thesis, 2012
... The population using the Western route through the Pyrenees and the Straits of Gibraltar is increasing during the past 20 years (probably thanks to the re-colonization of these countries by the species), however, it is still only around ten percent of the estimated European Black Stork population. ... ... sAllowed=y

Migration and winter distribution of Iberian and central European black storks Ciconia nigra moving to Africa across the Strait of Gibraltar: a comparative study
Luis Santiago Cano, José Luis Tellería
Abstract: This paper compares the migratory movements of Iberian and central European satellite‐tagged black storks Ciconia nigra moving to Africa across the Strait of Gibraltar. Results show that the populations differ in departure dates from breeding areas (central European birds start to move 15 d before Iberian birds), cross the Strait of Gibraltar together and reach the Sahel on similar dates. This synchronic arrival to the Sahel may be related with the onset of suitable conditions for the species after summer rains, when many pools are available for fishing. In this area, Iberian birds occupied westernmost localities compared to central European birds crossing the Strait of Gibraltar, which were distributed closer to those storks arriving in Africa across the Bosporus. This suggests that the parallel distribution of breeding and wintering areas results from posterior rearrangements of the two populations crossing Gibraltar. These patterns appear to be linked to the increasing population of central European black storks located on the western side of the migratory divide that moves throughout the western flyway to sectors of the Sahel close to their ancestral wintering grounds. ... 12.05824.x

Other Routes

Breeding and MIGRATION of the Black Stork (Ciconia nigra), with special regard to a Central European population and the impact of hydro-meteorological factors and wetland status
Tamás Enikő Anna; Doctoral (PhD) thesis, 2012
... The Mediterranean migration route is represented only with around 0,2% of the Black Storks in the autumn passage, according to observations and recoveries mostly 1st year and immature birds, a significant number of which is not proven to survive (or proven not to survive).
Migrating Black Storks are in low numbers but regularly observed in Greek islands (pers. comm. Kakalis, Noidou). The number of these individuals totals 15-20 in autumn, according to observers. However, the targeted wintering grounds and the places of origin of these birds are still unknown; there was one case when a first calendar year Black Stork colour-ringed as pullus in Croatia was observed in Crete (pers. comm. Mikuska). ...
... There is supposed to be some regular Black Stork movement in Yemen towards Africa across the Red Sea as well, but numbers cannot be given at present knowledge, furthermore, there is even no estimate about the origin of these individuals (pers. comm. Balázs). ... ... sAllowed=y

At the crossroads from Asia to Europe: spring migration of raptors and black storks in Dadia National Park (Greece)
Stefan Schindlera, Kostas Poirazidisc, Carlos Ruizc, Chiara Scandolarac, Beatriz Cárcamoc, Chris Easthame and Giorgos Catsadorakisc
Abstract: Migrating raptors and black storks (Ciconia nigra) were studied in Dadia National Park, Greece, during spring 2003–2005. Vantage points and transects were used to evaluate magnitude, phenology, local variation and direction. We observed 23 species and 2030 individuals, including 715 common buzzards (Buteo buteo), 547 black storks and 136 short-toed eagles (Circaetus gallicus). Species-specific migration peaks were detected, starting in the second half of March, e.g. common buzzard, short-toed eagle, black stork, and ending early May, e.g. Levant sparrowhawk (Accipiter brevipes), red-footed falcon (Falco vespertinus), honey buzzard (Pernis apivorus). Most raptors were observed in the Evros valley, which may function as a migration corridor. The average direction of passing raptors was north. Species’ proportions and phenology in the study area were similar to those in neighbouring Bosphorus and Marmara Flyways. Further migration monitoring should be established in the area, which will provide important information not least to inform wind farm development location. ... on_JNH.pdf

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