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Re: What We Know About Black Storks

Posted: August 15th, 2019, 6:04 pm
by Biker
by Jo UK » August 14th, 2019, 2:58 pm
Posted by biker 14.08.2019

Wing Feathers

Feathers and flight ... and-flight
I was unsure about posting it directly also here. informations which there were published are about flight etc in general and not specifical about Black Storks.

Therefore: thanks for copying that links here.

Here the same again:

not specifical about Black Storks but a study

from 2013

well i don't know what models the Black storks have got, and if this danger current for them. But it is not less interesting than the links i posted above
It's a little bit worrisome already, because of the lack of knowledge on my part, which model the Black Storks wear, wether is it a more developed etc ... etteri.pdf

Re: What We Know About Black Storks

Posted: August 15th, 2019, 9:02 pm
by pica

when i suggested to put scientific matters apart, i knew, there would be many... but so many?

thank you all for sharing all these items :thumbs:

Re: What We Know About Black Storks

Posted: August 16th, 2019, 7:18 am
by Liz01
Causes of Ring-Related Leg Injuries in Birds – Evidence and Recommendations from Four Field Studies
One of the main techniques for recognizing individuals in avian field research is marking birds with plastic and metal leg rings. However, in some species individuals may react negatively to rings, causing leg injuries and, in extreme cases, the loss of a foot or limb. Here, we report problems that arise from ringing and illustrate solutions based on field data from Brown Thornbills (Acanthiza pusilla) (2 populations), Siberian Jays (Perisoreus infaustus) and Purple-crowned Fairy-wrens (Malurus coronatus). We encountered three problems caused by plastic rings: inflammations triggered by material accumulating under the ring (Purple-crowned Fairy-wrens), contact inflammations as a consequence of plastic rings touching the foot or tibio-tarsal joint (Brown Thornbills), and toes or the foot getting trapped in partly unwrapped flat-band colour rings (Siberian Jays). Metal rings caused two problems: the edges of aluminium rings bent inwards if mounted on top of each other (Brown Thornbills), and too small a ring size led to inflammation (Purple-crowned Fairy-wrens). We overcame these problems by changing the ringing technique (using different ring types or larger rings), or using different adhesive. Additionally, we developed and tested a novel, simple technique of gluing plastic rings onto metal rings in Brown Thornbills. A review of studies reporting ring injuries (N = 23) showed that small birds (<55 g body weight) are more prone to leg infections while larger birds (>35 g) tend to get rings stuck over their feet. We give methodological advice on how these problems can be avoided, and suggest a ringing hazard index to compare the impact of ringing in terms of injury on different bird species. Finally, to facilitate improvements in ringing techniques, we encourage online deposition of information regarding ringing injuries of birds at a website hosted by the European Union for Bird Ringing (EURING). ... ne.0051891

Re: What We Know About Black Storks

Posted: August 16th, 2019, 2:28 pm
by Liz01

Searching for thermals

Travelling storks

I think it is almost the same as with black Storks.

Re: What We Know About Black Storks

Posted: August 16th, 2019, 4:43 pm
by Anne7
Bird anatomy

5. Digestive system

Re: What We Know About Black Storks

Posted: August 16th, 2019, 4:57 pm
by Anne7
Bird anatomy

6. Reproductive and urogenital systems

Egg Formation, egg Structure, laying schedule, …

Relevance of turning the eggs
Broody hens provide optimum conditions for embryos developing in the eggs they are sitting on. The brood patch provides heat from one direction only, and the eggs at the side of the patch are cooler than those in the middle of the nest. However, because the broody hen regularly turns and moves the eggs in the nest, uniform egg temperature is achieved. ... rning.html

The Art of Hatching an Egg, Explained
Tim Birkhead ... -explained

The Most Perfect Thing - Inside (and Outside) a Bird’s Egg (book)
Tim Birkhead
"I think that, if required on pain of death to name instantly the most perfect thing in the universe, I should risk my fate on a bird's egg"
Thomas Wentworth Higginson, 1862
How are eggs of different shapes made, and why are they the shape they are? When does the shell of an egg harden? Why do some eggs contain two yolks? How are the colours and patterns of an eggshell created, and why do they vary? And which end of an egg is laid first - the blunt end or the pointy end? These are just some of the questions "A Bird's Egg" answers, as the journey of a bird's egg from creation and fertilisation to its eventual hatching is examined, with current scientific knowledge placed within an historical context. Beginning with an examination of the stunning eggs of the guillemot, each of which is so variable in pattern and colour that no two are ever the same, acclaimed ornithologist Tim Birkhead then looks at the eggs of hens, cuckoos and many other birds, revealing weird and wonderful facts about these miracles of nature. Woven around and supporting these facts are extraordinary stories of the individuals who from as far back as Ancient Egypt have been fixated on the study and collection of eggs, not always to the benefit of their conservation. Firmly grounded in science and enriched by a wealth of observation drawn from a lifetime spent studying birds, "A Bird's Egg" is an illuminating and engaging exploration of the science behind eggs and the history of man's obsession with them.

An Egg’s Incredible Journey

Avian Reproduction: Anatomy & the Bird Egg

Contributed by Liz01
Incubation: Warming the Egg
© 1988 by Paul R. Ehrlich, David S. Dobkin, and Darryl Wheye
For an egg to develop normally, it must be exposed for a considerable length of time to temperatures a few degrees below the normal 104 degrees F (40 degrees C) avian body temperature. Indeed, the ideal incubation temperature for many birds' eggs is about human body temperature, 98.6 degrees F. Almost all birds create the required temperature by sitting on the eggs and incubating them, often transferring heat via a temporarily bare area of abdominal skin called the "brood patch." A few birds, like penguins, pelicans, and gannets, transfer heat through their webbed feet. A unique form of incubation is found in the turkey-like megapodes of Australia. They heat their eggs by depositing them in a large mound of decaying vegetation, which the birds have scratched together. By opening and closing the mound as needed, the birds carefully regulate the heat of decomposition, which takes the place of the parental body heat used in normal incubation.
On the other hand, the embryo inside the egg is also very sensitive to high temperatures, so that in some situations eggs must be protected from the sun. Ducks with open nests, for example, will pull downy feathers (originally plucked to form their brood patches) over the nest to cover the eggs when they leave it, providing shade if the weather is hot and helping to retard heat loss when it is cold. Open-nesting ducks usually have camouflage down that does not reveal the nest's location; hole-nesting ducks have white down. Other species may stand over the nest and shade the eggs when temperatures rise. Killdeer and some other shorebirds soak the feathers of their bellies and use them to wet the eggs before shading, thus helping to cool the developing embryos by evaporative heat loss.
Embryos are less sensitive to cold than to heat, particularly before incubation has started. Mallard eggs have been known to crack by freezing and still hatch successfully. Eggs cool when incubation is interrupted, but this is not usually harmful, and few birds incubate continuously. Instead, egg temperature is regulated in response to changes in the temperature of the environment by varying the length of time that a parent bird sits on them or the tightness of the "sit." For instance, female House Wrens (which incubate without help from the males) sat on the eggs for periods averaging 14 minutes when the temperature was 59 degrees F (15 degrees C), but an average of only 7.5 minutes when it rose to 86 degrees F (30 degrees C).
Many birds apparently sense the egg temperature with receptors in the brood patches, which helps them to regulate their attentiveness (time spent incubating) more accurately. Since the embryo itself increasingly generates heat as it develops, periods of attentiveness should generally decline as incubation progresses. Attentiveness is also influenced by the insulating properties of a particular nest.
Eggs are also turned periodically -- from about every eight minutes by American Redstarts to once an hour by Mallards. The turning presumably helps to warm the eggs more evenly, and to prevent embryonic membranes from sticking to the shell. ... ation.html

Posted here: viewtopic.php?p=599880#p599880
Hatching strategies – when and why?
By Daryl Anne Goldman
... The female deposits differing amounts of hormones, immunoglobulins, and antioxidants in the yolk, albumen, and shells of the eggs she lays, which then affects the survival of each hatchling. For instance, in some species, yolk antioxidant and immunoglobulin concentrations may decrease across laying order, thus handicapping the immune system of the last-hatched chicks. However, in the same species, yolk testosterone concentrations may increase with laying order, which may compensate for poorer immune function by helping accelerate growth and food begging rates. ...
"... There is a higher rate of mortality with this hatching strategy (asynchronous hatching), and the last chick is usually not expected to survive and is more of an insurance policy against the loss of the first offspring. ... In some bird species, the firstborn, stronger chicks or even the parents may push the weaker, last-born chick(s) out of the nest." ... trategies/

BACK TO THE TABLE OF CONTENTS » viewtopic.php?p=685683#p685683

Re: What We Know About Black Storks

Posted: August 16th, 2019, 5:33 pm
by Anne7
Bird anatomy

7. Nervous system

8. Immune system

Re: What We Know About Black Storks

Posted: August 16th, 2019, 8:40 pm
by Liz01
Influence of weather conditions on the flight of migrating black storks

This study tested the potential influence of meteorological parameters (temperature, humidity, wind direction, thermal convection) on different migration characteristics (namely flight speed, altitude and direction and daily distance) in 16 black storks (Ciconia nigra).
The birds were tracked by satellite during their entire autumnal and spring migration, from 1998 to 2006. Our data reveal that during their 27-day-long migration between Europe and Africa (mean distance of 4100 km), the periods of maximum flight activity corresponded to periods of maximum thermal energy, underlining the importance of atmospheric thermal convection in the migratory flight of the black stork. In some cases, tailwind was recorded at the same altitude and position as the birds, and was associated with a significant rise in flight speed, but wind often produced a side azimuth along the birds' migratory route. Whatever the season, the distance travelled daily was on average shorter in Europe than in Africa, with values of 200 and 270 km d−1, respectively. The fastest instantaneous flight speeds of up to 112 km h−1 were also observed above Africa. This observation confirms the hypothesis of thermal-dependant flight behaviour, and also reveals differences in flight costs between Europe and Africa. Furthermore, differences in food availability, a crucial factor for black storks during their flight between Europe and Africa, may also contribute to the above-mentioned shift in daily flight speeds. ... ack_storks

Re: What We Know About Black Storks

Posted: August 17th, 2019, 1:10 pm
by Liz01
The use of stopover sites by Black Storks (Ciconia nigra) migrating between West Europe and West Africa as revealed by satellite telemetry
Migration is known to be a bottleneck in the annual cycle of many birds, and its success can depend on the availability of stopovers along the migration route. Satellite tracking was used to identify migratory strategies and important stopovers in 16 Black Storks (Ciconia nigra) during their autumn and spring migrations between European breeding areas and West African wintering sites. Some birds migrate without using stopovers, whereas others need to stop at least once during their migration: 1–5 stopovers were observed per bird, and half of all stopovers were located in Spain. Precise GPS locations indicated that it is unlikely that the storks forage near their night roost, just after or before their migratory flights. For the birds that do make stopovers, the tracking data reveal both inter- and intra-individual variability in the use of stopovers over the two migrations, suggesting a lack of fidelity to such sites. The number of stopovers was similar for potential breeders and non-breeders, although the length of stopovers was significantly longer for non-breeders than for potential breeders. No difference in stopover duration was found between autumn and spring migrations. Six stopovers were considered as important ones, based on the time spent there (>10 days). This study underlines the importance of protected areas along migratory paths and the necessity to plan protective measures for those stopover sites. ... ck-Storks-(Ciconia-Chevallier-Maho/d39b762af4b39df711939b8b7f87794bd555a8cc

Slowly I think about which links are already here

Re: What We Know About Black Storks

Posted: August 17th, 2019, 3:30 pm
by Liz01
Longevity and survival of the black stork Ciconia nigra based on ring recoveries

Enik˝o Anna Tamás E¨otv¨os József College, Faculty of Technology and Economics, H-6500 Baja, Hungary, Bajcsy-Zs. u. 14; e-mail:
Abstract: To understand population dynamics, the determination of survival rates is very important. For the black stork Ciconia nigra no survival rate determination has been published to date. This might be due to the fact that ringing activity and recovery numbers in general are still relatively low for the species. The international black stork colour ringing
storks have been colour ringed worldwide, of which 1,069 individuals were marked in Hungary. This article’s objective is the determination of the survival rates for the black stork, as well as to estimate the longevity of the species based on live encounters of ringed individuals. The conclusions are that longevity can be estimated based on the data, and is in agreement with previous knowledge; and that the survival rate of the species, with our present knowledge, shows a significant difference between first year (0.1696, 0.1297–0.219) and older birds (0.838, 0.773–0.887).

In order to understand population dynamics, there is a need to assess how much variation in survival, reproduction or dispersal contributes to population change (Krebs 2009). The need to understand the limitations of bird populations and the factors influencing these arose
with the knowledge on declines in the abundances of many species (Robbins et al. 1989). Thus, to be aware
of survival rates are crucial for the understanding of the processes of population dynamics, and is very important for the development of an effective protection strategy especially in long-lived species (Sæther et al. 2005). Survival may be influenced by numerous factors,
among which breeding success, the status of the habitat used during migration and wintering situations all play important roles, as shown for some long-distance migrant species (e.g., Boyd & Piersma 2001). For the black stork Ciconia nigra (L. 1758) no survival rate determination has been published to date. This might be due to the fact that ringing activity and recovery numbers in general are still relatively low for this species. It has been reported by different authors Sellis 2003; Strazds 2003; Tamás et al. 2006) that the
population of the species in the Baltic countries is decreasing, concluding that the deterioration of habitats and human impacts in the breeding territories and feeding areas caused the decline. Over the same period in
Germany and France (Villarubias et al. 2003; Janssen et al. 2004) an increase of the population is reported, and in the 1980’s the species started to re-colonise territories in Belgium, Luxembourg and Denmark, from where it had previously been lost (Janssen et al. 2004).
So far, we haven’t examined population changes in detail, we have only given estimates based on the census of breeding pairs which is highly influenced by the activity of volunteers in certain areas (Kalocsa & Tamás 2010). For an effective population study survival rate
determination is vital. The international black stork colour ringing programme is taking place with the participation of 25 countries. In Central Europe, particularly in the Czech Republic, Poland and Hungary, the intensity of ringing of this species is high. Altogether more than 7,000 black storks have been colour ringed worldwide (pers. comm., van den Bossche 2010), of which 1069 individuals were
marked in Hungary (∼15%), which fits with the criterion of the minimal sample size according to Krejcie & Morgan (1970). The number of recoveries is the highest in Hungary among all European countries, ostensibly because of the high level of volunteer activity and the
favourable geographical location of this country, with lots of black storks migrating through it, and many migration stopover places identified within the Carpathian Basin. One of the goals that was established in 1994, at the start of the colour ringing programme, was to determine how long black storks live (Kalocsa & Tamás 2002). I set two objectives in the present study: to determine longevity and survival rate based on ringing recoveries. ......
Graphics with data and more information here ... 0090-6.pdf

Re: What We Know About Black Storks

Posted: August 17th, 2019, 3:35 pm
by Liz01
Brood sex ratio and nestling physiological condition as indicators of the influence of weather conditions on breeding black storks Ciconia nigra - 2019

Maciej Kamińskia-Jerzy Bańburab Bartosz- Janica Katrin Kaldmac- Annika Konovalovc -Lidia Marszała -Piotr Miniasd Ülo Välic-Piotr Zielińskia

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. ... via%3Dihub

Re: What We Know About Black Storks

Posted: August 18th, 2019, 4:09 pm
by Ari19
Migration of juvenile Black Storks: stay with the family or go alone?


For many migratory species, social interactions on migration are poorly known, particularly the extent to which brood siblings remain together, at least during their first post-fledging migration. This study tested the assumption that Black Stork siblings stay together during migration and is the first time that juveniles from the same brood of a Palearctic sub-Saharan migratory stork species have been tracked on migration. Four juveniles from the same brood were followed by satellite tracking, and each dispersed or migrated in a completely different direction to its siblings. The results thus refute the idea that Black Stork siblings remain together on their first migration, but to confirm these new findings, it is important to repeat the study using additional nests.

Full Text

Since the early 1970s, the migratory behaviour of many species, especially birds, has been studied to understand the mechanisms of biodiversity loss at international levels and to allow appropriate conservation measures to be established (Canterbury et al 2000, Nguyen 2007). Migration represents an adaptive response to survival when an environment becomes periodically unfavourable. Migratory avian species are of particular interest because they use very different habitats during their life cycle, and across large spatial scales (Carignan & Villard 2002). Thus, in many avian species, individuals migrate annually between breeding and wintering regions (Zucca 2010) and these migratory phases are well documented (Greenwood & Harvey 1982, Balmer et al 2013). Many species travel and rest in groups from departure until their arrival on wintering or breeding areas and much research has focused on gregarious behaviours well known in Anatidae (ducks, geese and swans) and in Gruidae (cranes) (Frederick & Klaas 1982, Johnsgard 1983, Arzel et al 2006, Helm et al 2006); however, social associations are poorly known in migratory species that are less gregarious. In the Black Stork Ciconia nigra, a Palearctic sub-Saharan migratory species, individuals can aggregate in small groups during pre-migration periods (pre- and post-nuptial migration) and during the wintering period, when birds form groups in open habitats, a behaviour thought to reduce vulnerability to predation (Grischenko 1995, Tamás 2012). In contrast, grouping behaviour by Black Storks on migration is poorly documented because it is difficult to observe in situ (Perrins & Middleton 1985, Li et al 2011). In particular, it is not known whether some individuals migrate in family groups or whether brood siblings stay together for their first migration. For example, juvenile Snow Geese Anser caerulescens use the same migration route and at the same time as their parents after fledging (Nagel 1969). Since Black Storks of either sex tolerate their partner and chicks only during the breeding period (del Hoyo et al 1992), it is possible that juveniles from the same brood might migrate together for safety. As a result of technological innovations for animal tracking such as Argos-GPS tags, the migratory movements of this species can now be studied in detail (Bobek et al 2003, Chevallier et al 2010). Therefore, to test the hypothesis that siblings migrate together, four juvenile Black Storks from the same brood were followed by satellite tracking.
For our study, we chose a nest located in a 70-year-old maritime pine Pinus pinaster, which had been used by a pair of Black Storks for three years. The surrounding habitat of the nest comprised maritime pine forests, meadows, ponds and lakes. During the 2006 breeding season in western France, four juvenile Black Storks from this nest, the entire brood, were each fitted with

Figure 1. Satellite tracking of four juveniles from the same brood, tracked between July 2006 and February 2007. PTT tags (birds): 62 938, yellow; 62 970, blue; 62 937, orange; 44 855, red. The nest site, in France, is marked with a filled triangle.
Solar-GPS and Solar Argos PTTs (PTT-100 Solar Argos/ GPS PTT 45 g and 75 g, respectively, Microwave Telemetry, USA). These tags were attached using a Teflon (resistant and non-abrasive) harness, as high as possible on the stork’s back so that feathers did not obscure the solar panels. The tags were programmed to collect data every hour during daylight, between 0600 and 2200 GMT. For each location obtained (coordinated latitude and longitude), complementary data on date, hour and altitude were recorded. QGIS software was used to overlay location data onto maps to compare the migration routes of the four birds.
The first flight of the juveniles occurred between 19 July (for the oldest bird) and 31 July 2006 (the youngest bird). During these first flights, the siblings remained within 7 km of the nest and returned every evening to roost at the nest. This flight-learning phase lasted for about 30 days. It was followed by a dispersal phase, resulting in the definitive dispersal of the juveniles from the nest. As the starting of this second phase was related to the age of the juvenile, there was a gap in the departure dates. As shown in Figure 1 and Table 1, the final locations were recorded between 17 and 20 August 2006 and the juveniles had each gone in different directions: these observations are summarised in Table 1.
Table 1. Summary of travel information for each juvenile.
To summarise, our study shows an absence of gregarious behaviour of siblings during their migration, and completely different migratory paths. Therefore, these results refute our hypothesis: our initial expectation was that the four juvenile siblings would migrate together for safety and because of inexperience. In contrast, juvenile Snow Geese are known to use the same migration route (Nagel 1969) and studies have shown that the migratory behaviour of juvenile White Stork Ciconia ciconia is directly influenced by social interactions between juveniles (Chernetsov et al 2004). However, erratic behaviour is not uncommon in juvenile Black Storks until three years old, when the age of sexual maturity is reached (Jadoul et al 2003). Furthermore, a common assumption for this species is that members of the same family will remain as a group during migration. This is the first study to have tested such an assumption by tracking juveniles from the same brood of a Palearctic sub-Saharan migratory ciconiid species during their first long-distance movements from the nest.
The results for juvenile Black Storks match data for Bulgarian and Greek Egyptian Vultures Neophron percnopterus (Oppel et al 2015). However, given that this present study was limited to a single nest, it important to extend the work to additional nests to determine whether environmental constraints affect the migration behaviour of juvenile Black Storks (Chevallier et al 2010, personal data). Such studies are necessary to facilitate better protection and conservation of Black Storks throughout their annual cycle. ... r_go_alone

Re: What We Know About Black Storks

Posted: August 19th, 2019, 12:24 am
by Anne7
Wings, Flight and Feathers

Vertebrate Flight

John R. Hutchinson (edited by Kevin Padian and Dave Smith)
Flight is an amazing accomplishment, evolved only three times in the 500 million years of vertebrate history. By contrast, the invertebrates have only evolved flight once: in the insects, which were the first animals to evolve flight. We won't discuss insect flight here, as the diversity of flight types seen in insects really deserves a set of exhibits all its own. Good sources about insect flight include "The Biomechanics of Insect Flight", by Robert Dudley, and "Solving the Mystery of Insect Flight" by Michael Dickinson (Scientific American, June 2001). However, the same rules that govern vertebrate flight also apply to insect flight, so you can also use the information given here when considering insects. The question is, how do vertebrates manage to overcome the weight of their bodies in order to take to the skies? Let's look at how different animals move through the air, and then see what flight is all about. ... intro.html

Vertebrate Flight

John R. Hutchinson (edited by Dave Smith)
To understand flight, you must have a basic knowledge of the principles of physics, in this case categorized as biomechanics. Individuals at the UCMP and the Berkeley Department of Integrative Biology are leading experts in this field, which applies the laws of physics to organisms in an effort to understand how organisms function, and to perhaps answer questions such as : "How do organisms work?," "How do the laws of physics limit what organisms can do?," or "What can physics tell us about evolutionary possibilities for organisms?" and so on. If you particularly enjoy these exhibits, try our dinosaur speeds exhibit for a similar exercise in biomechanics. ... ysics.html

Vertebrate Flight

John R. Hutchinson (edited by Dave Smith)
As discussed previously, the difference between powered flight and gliding is the flight stroke, which produces thrust in true flyers. Gliders, then, do not produce thrust; they do not flap their wings. Indeed, a glider might compromise its lift production (i.e., fall) if it tried to do so — its gliding membrane would be too small to maintain enough lift to keep the animal aloft.
When looking at the structure of an animal, without knowing its behavior (whether it flies or not) we can note some common differences between typical flyers and gliders. Most importantly, flyers have an elongated distal wing, which is flapped to produce thrust. To flap the wings, they need strong shoulder muscles, so a keeled sternum (breastbone), large humerus (upper arm bone), and modified shoulder girdle are indicative of powered flight. Also, the forearms of flyers are more elongated than in gliders, although the hands exterior to the wing are usually small. Flyers need a rigid, confined power stroke to enhance stability, so motion of the arms should be limited by the joints that are involved in the flight stroke. And the wing should be stiffened by some structural elements (e.g., fibers in pterosaurs, feathers in birds, fingers in bats).
In contrast, gliders usually retain the locomotory abilities of their ancestors, most notably climbing and leaping adaptations (which include mobile joints and large hands). Some gliders have elongated ribs which support the gliding membrane (no flyers do this). Aerodynamically, gliders are less manoeuvrable (although they can still be very manoeuvrable) and have a lower aspect ratio (wing length/wing breadth) than flyers. So, if we find the remains of an animal, we can be pretty sure whether it glided or flew. ... iding.html

Vertebrate Flight

John R. Hutchinson (edited by Dave Smith)
The most diverse group of flyers ever to evolve are the birds (the clade Aves). Birds show a marvelous diversity not only of species but of flight adaptations. Compare the hummingbird with the albatross, and you'll get a good picture of how differently animals can fly. As is discussed in our bird origins exhibit, current theory holds that birds had a common ancestor with dromaeosaurid dinosaurs during the Late Jurassic period (about 150 million years ago), if not earlier. Birds remained of relatively low diversity until the Cretaceous period.

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

Posted by Solo: viewtopic.php?p=616308#p616308
The reasons why bird wings are so amazing
By Christina Holvey
Why does an albatross soar on slender, motionless wings while a little house sparrow flaps small, stubby ones nineteen to the dozen? The shape and size of a bird’s wings are defined in no small part by their owner’s travel requirements, as well as by their lifestyle. Here’s your guide to the wonderfully revealing world of bird wings. ...
Thermals are created when the sun warms the ground, which in turn warms the air directly above it. The warmer air close to the surface expands to become less dense than the surrounding air and rises, taking even large and heavy birds such as eagles, hawks and storks along for the ride. Using these invisible elevators, golden eagles can climb several hundred metres without expending any energy. Once high in the skies, they are able to soar effortlessly around at an unhurried speed of 30mph, which is perfect for surveying their territories and spotting prey.
Storks use passive soaring wings for a different reason – to navigate long migration routes. White storks (Ciconia ciconia) journey annually between Europe and Sub-Saharan Africa and, for many, the shortest route would take them over a large stretch of the Mediterranean Sea. As air thermals don’t form over water, however, the storks would have to employ energetic wing-flapping to use such a route, a technique that burns 23 times more body fat than soaring over land. Instead, they cross over at the Strait of Gibraltar, where Europe and Africa are separated by a mere 7.7 nautical miles of ocean.
The storks rise as high as they can over the southern tip of Spain, after which they “surf” above the sea at height before once again picking up the thermals over land in north Africa. ... ... bird-wings

The biophysics of bird flight: functional relationships integrate aerodynamics, morphology, kinematics, muscles, and sensors 2015
Douglas L. Altshuler, Joseph W. Bahlman, Roslyn Dakin, Andrea H. Gaede, Benjamin Goller, David Lentink, Paolo S. Segre, and Dimitri A. Skandalis
Abstract: Bird flight is a remarkable adaptation that has allowed the approximately 10 000 extant species to colonize all terrestrial habitats on earth including high elevations, polar regions, distant islands, arid deserts, and many others. Birds exhibit numerous physiological and biomechanical adaptations for flight. Although bird flight is often studied at the level of aerodynamics, morphology, wingbeat kinematics, muscle activity, or sensory guidance independently, in reality these systems are naturally integrated. There has been an abundance of new studies in these mechanistic aspects of avian biology but comparatively less recent work on the physiological ecology of avian flight. Here we review research at the interface of the systems used in flight control and discuss several common themes. Modulation of aerodynamic forces to respond to different challenges is driven by three primary mechanisms: wing velocity about the shoulder, shape within the wing, and angle of attack. For birds that flap, the distinction between velocity and shape modulation synthesizes diverse studies in morphology, wing motion, and motor control. Recently developed tools for studying bird flight are influencing multiple areas of investigation, and in particular the role of sensory systems in flight control. How sensory information is transformed into motor commands in the avian brain remains, however, a largely unexplored frontier. ... 6735fa.pdf

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.

Bird flight
Bird flight is the primary mode of locomotion used by most bird species in which birds take off and fly. Flight assists birds with feeding, breeding, avoiding predators, and migrating.
Bird flight is one of the most complex forms of locomotion in the animal kingdom. Each facet of this type of motion, including hovering, taking off, and landing, involves many complex movements. As different bird species adapted over millions of years through evolution for specific environments, prey, predators, and other needs, they developed specializations in their wings, and acquired different forms of flight.
Various theories exist about how bird flight evolved, including flight from falling or gliding (the trees down hypothesis), from running or leaping (the ground up hypothesis), from wing-assisted incline running or from proavis (pouncing) behavior.

Contributed by Biker
Feathers and flight
Science Learning Hub
A bird is designed for flight. The combination of light weight, strength and shape, as well as precision control, is largely responsible for giving birds their special ability for sustained flight. Every part gives maximum power with a minimum of weight. The heavier the animal, the bigger its wings need to be. The bigger the wings, the more muscle is needed to move them. ...
Image ... and-flight

Contributed by Biker
Wing Feathers
Pepper W. Trail
Senior Forensic Scientist / Ornithologist National Fish & Wildlife Forensics Laboratory Ashland, OR 97520

PURPOSE: Providing an introduction to the topography of the avian wing, to the form and function of wing flight feathers, and to the use of flight feathers for determining the minimum number of individuals (mni)

Everything You Need To Know About Feathers 2014
Feather Anatomy: How Do Feathers Work?

Mya Thompson, Bird Academy. Illustrations: Andrew Leach, Jeff Szuc
Although feathers come in an incredible diversity of forms, they are all composed of the protein beta-keratin and made up of the same basic parts, arranged in a branching structure. In the most complex feathers, the calamus extends into a central rachis which branches into barbs, and then into barbules with small hooks that interlock with nearby barbules. The diversity in feathers comes from the evolution of small modifications in this basic branching structure to serve different functions.
Downy feathers look fluffy because they have a loosely arranged plumulaceous microstructure with flexible barbs and relatively long barbules that trap air close to the bird’s warm body. Pennaceous feathers are stiff and mostly flat, a big difference that comes from a small alteration in structure; microscopic hooks on the barbules that interlock to form a wind and waterproof barrier that allows birds to fly and stay dry. Many feathers have both fluffy plumulaceous regions and more structured pennaceous regions.
Feather types:

Everything You Need To Know About Feathers
Feather Function: What do feathers do?
Each feather on a bird’s body is a finely tuned structure that serves an important role in the bird’s activities. Feathers allow birds to fly, but they also help them show off, blend in, stay warm, and keep dry. Some feathers evolved as specialized airfoil for efficient flight. Others have been shaped into extreme ornamental forms that create impressive displays but may even hinder mobility. Often we can readily tell how a feather functions, but sometimes the role of a feather is mysterious and we need a scientific study to fill in the picture.

Everything You Need To Know About Feathers
Feather Growth: How do feathers develop?
Feathers are dead structures that cannot repair themselves when damaged. Because a healthy and functional coat is critical to survival, each year birds shed their old feathers and then grow a whole new set. This molting process is a carefully timed affair in which feathers are shed and regenerate in turn over a period of weeks so the bird can maintain its protective outer layer and ability to fly. Once the new set of feathers has matured, molt is complete and new growth only occurs before the next molt cycle when feathers are accidentally lost.
The growth process:

Cross sectional geometry of the forelimb (wing) skeleton and flight mode in pelecaniform birds.
Erin L. R. Simons, Tobin L Hieronymus, Patrick M. O'Connor;
Published in Journal of morphology 2011

Avian wing elements have been shown to experience both dorsoventral bending and torsional loads during flapping flight. However, not all birds use continuous flapping as a primary flight strategy. The pelecaniforms exhibit extraordinary diversity in flight mode, utilizing flapping, flap-gliding, and soaring. Here we (1) characterize the cross-sectional geometry of the three main wing bone (humerus, ulna, carpometacarpus), (2) use elements of beam theory to estimate resistance to loading, and (3) examine patterns of variation in hypothesized loading resistance relative to flight and diving mode in 16 species of pelecaniform birds. Patterns emerge that are common to all species, as well as some characteristics that are flight- and diving-mode specific. In all birds examined, the distal most wing segment (carpometacarpus) is the most elliptical (relatively high I(max) /I(min) ) at mid-shaft, suggesting a shape optimized to resist bending loads in a dorsoventral direction. As primary flight feathers attach at an oblique angle relative to the long axis of the carpometacarpus, they are likely responsible for inducing bending of this element during flight. Moreover, among flight modes examined the flapping group (cormorants) exhibits more elliptical humeri and carpometacarpi than other flight modes, perhaps pertaining to the higher frequency of bending loads in these elements. The soaring birds (pelicans and gannets) exhibit wing elements with near-circular cross-sections and higher polar moments of area than in the flap and flap-gliding birds, suggesting shapes optimized to offer increased resistance to torsional loads. This analysis of cross-sectional geometry has enhanced our interpretation of how the wing elements are being loaded and ultimately how they are being used during normal activities.
Fig. 7. Illustration of wing anatomy of (A) Morus bassanus (OUVC 10587) (the northern gannet), and (B) Pelecanus occidentalis (OUVC 10586) in ventral view. (C) Schematic of the distal forelimb skeleton and proximal feather attachments. The secondary flight feathers (shaded light gray in A and B) are oriented perpendicular to the axis of the ulna. The primary flight feathers are oriented obliquely to the axis of the carpometacarpus. Note also difference in mean chord length (width of wing) between species. Abbreviations: CMCmaj, major metacarpal; CMCmin, minor metacarpal. ... a15aaad3cc

Posted here: viewtopic.php?p=635938#p635938
The six degrees of freedom
Translational motion: (Translational motion is the motion by which a body shifts from one point in space to another.)
Moving forward and backward on the X-axis. (Surge)
Moving left and right on the Y-axis. (Sway)
Moving up and down on the Z-axis. (Heave)
Rotational motion:
Tilting side to side on the X-axis. (Roll)
Tilting forward and backward on the Y-axis. (Pitch)
Turning left and right on the Z-axis. (Yaw)

This very helpful video animation is about Roll - Pitch - Yaw
© Mark Wood

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Re: What We Know About Black Storks

Posted: August 19th, 2019, 12:47 am
by Ari19
Anne7 wrote:
August 19th, 2019, 12:24 am
:hi: Yes, Ari, it becomes hard to see if we don't post the same article twice. :nod:
What I do when I have doubts: I copy part of the new title (keywords) and paste it (between " " ) in the search tool (on top at the right).
If the same article has already been posted, it will be found this way.

Once everything will be arranged according to their theme, the checking on "doubles" will probably be easier.
Ah, that makes so much sense! Thank you Anne7! :wave:

Re: What We Know About Black Storks

Posted: August 19th, 2019, 1:33 pm
by Anne7
Bird vocalization

Contributed by Liz01
xeno-canto Bird sounds from all over the world
Black Stork

Communication and Perception
Though they are loudest of all storks, C. nigra are fairly quiet birds. They have few loud vocalizations, using low grunts, whistles and hisses, in a che lee che lee pattern. Most vocal communication takes place in the form of the bill-chattering during mating season. ("Storks (Ciconiidae)", 2003; Campbell, 1974; Perring and Middleton, 1985; Thompson, 1964)
Information is processed visually by C. nigra. They hunt by eye-sight, unlike some of their relatives, which catch prey by touch. Black storks also use vision and sound when finding a mate. ("Storks (Ciconiidae)", 2003; Campbell, 1974; Perring and Middleton, 1985; Thompson, 1964)

Bird vocalization

Bird Voices
by Paul R. Ehrlich, David S. Dobkin, and Darryl Wheye
The organ that birds use to produce vocalizations (songs and calls) is very different in location and structure from our own. The mammalian larynx is located at the top of the "windpipe" (trachea), and contains hard membranes (vocal cords) whose vibration as air passes is controlled by a complex of muscles and cartilage. The vocal organ of birds, in contrast, is a unique bony structure called a syrinx, which lies at the lower end of the trachea, is surrounded by an air sac, and may be deep in the breast cavity. Thus situated, the syrinx becomes a resonating chamber (the air sac may resonate also) in conjunction with highly elastic vibrating membranes. Specialized sets of syringeal muscles control the movement of the syrinx, including the tension on the membranes (which can be adjusted like the skin of a drum). Birds can vary both the intensity (loudness) and frequency (pitch) of sounds by altering the air pressure passing from the lungs to the syrinx and by varying the tension exerted by the syringeal muscles on the membranes. The attributes of song that characterize individual species appear to result mostly from differences in the learning process rather than from differences in the structure of the vocal apparatus.
Neurobiologist Fernando Nottebohm has shown that the two sides of the syrinx are independently controlled, which explains the "two-voice" phenomenon seen in sonograms of some species: simultaneous double tones that are nonharmonically related and therefore must be derived from two independent acoustic sources. Our understanding of how the syrinx works is based on studies of only a very few species (including the domestic chicken and Mallard, which hardly typify birds in general), and many of our ideas about how the passerine syrinx functions are based on "informed guesswork."
Recent work on the neural basis of song in passerines by Nottebohm and his colleagues not only identified the specific regions in the brain that control song production but also demonstrated differences between the sexes in the size of these regions. The substantially smaller size of these areas in female Canaries and Zebra Finches suggests an explanation for their inability to sing. The assertion that singing ability is dependent on the amount of brain space allocated to it is further supported by Nottebohm's demonstration that superior singers among male Canaries, Zebra Finches, and Marsh Wrens have larger song control regions in their brains. In fact, Pacific Coast Marsh Wrens, which have song repertoires that are three times larger than Atlantic Coast birds, have 30-40 percent larger song control areas in their brains. ... oices.html

Vocal Development
by Paul R. Ehrlich, David S. Dobkin, and Darryl Wheye
With practice, most birders learn to identify many species by their characteristic calls and songs. What are the underlying mechanisms that lead to "standardized" repertoires for each species? Are these characteristic sounds learned or are they genetically determined and fixed without learning (innate)? Where learning is involved, when does it take place? And how does each species "know" which sounds are appropriate and should be learned? The answers to these questions are as varied as birds themselves and have long served as a focus of research by ornithologists, ethologists, and neurobiologists.
Most of this research has been concerned with song development in species of songbirds, but relatively few species have been examined in detail. Most songbirds must learn at least part of their song repertoire. What little we know of vocal development in nonpasserines indicates that calls of those species (Mallard, American Coot, Ring-billed and Franklin's Gulls, domestic chicken, and Ringed Turtledove) are innate rather than learned, and that precocial young tend to have larger, better-developed repertoires of calls than do altricial young. Two exceptions among nonpasserines are hummingbirds and parrots, for which there is some evidence of vocal learning (there also is suggestive evidence for Greater Prairie-Chicken and Sharp-tailed Grouse). Studies of many groups have yet to be done.
The learning of songs is a gradual process that takes place over a period of weeks or months. Typically, a vague, jumbled "subsong" appears first which then gradually is transformed into a more structured, but still quite variable, "plastic song." The endpoint of this process is the production of a stable repertoire of "crystallized" songs. Much more material may be developed than is actually needed for the eventual crystallized repertoire, leading to a process of attrition as the mature song takes shape. Swamp Sparrows, for example, generate four to five times more song material during development than they eventually retain in the adult repertoire. ... pment.html

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Re: What We Know About Black Storks

Posted: August 19th, 2019, 7:29 pm
by Ari19
Predominance of maternal investment during the incubation period in the Black Stork

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. cico- nia) 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

Re: What We Know About Black Storks

Posted: August 19th, 2019, 7:37 pm
by Ari19
Form and function of aerial courtship displays in Black Storks Ciconia nigra

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 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 (Parallel Soaring). 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, Whiffling and 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 elaborat- ed 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

Re: What We Know About Black Storks

Posted: August 19th, 2019, 7:43 pm
by Bea
☼ ☼ ☼

IUCN-SSC Stork, Ibis and Spoonbill Specialist Group Special Publication 1.

VII International Conference on Black Stork Ciconia nigra: programme and abstracts
Doñana National Park, Spain. 28th-30th November 2018

Editors: Luis Santiago Cano Alonso and K. S. Gopi Sundar ... tracts.pdf




Plenary Discussion, Conclusions and Recommendations of the VII International Conference on Black Stork Ciconia nigra
(Doñana National Park, Spain)
Luis Santiago Canoa,, EnikőAnnaTamás and Maris Strazds ... ations.pdf


A lot of Historical literature

Probably most of this is already known and published here, in case it is so feel free to simply delete this here and kick it out :wink:

Re: What We Know About Black Storks

Posted: August 19th, 2019, 7:44 pm
by Ari19
The structure and composition of the white and black storks’ eggshells – preliminary results ... ry_results

Re: What We Know About Black Storks

Posted: August 19th, 2019, 8:24 pm
by Biker
>> reasons for equip female Black Storks with satellite transmitters
>> what role do chemicals play for the high mortality especially of young female Black Storks?

Tracking of the Black Storks is part of project "Priority actions for Black Stork conservation in Latvia" carried out by Latvian Ornithological Society and funded by Latvian Environmental Protection Fund and Max Planck Institute for Ornithology. It will be possible to follow the movements of Black Storks in the website Project is also supported by TV channel "LNT".