the fishie was not small but not very big either and yet it prevented the eagle from getting airborne. i think that one could estimate the weight how much an eagle can take in the air based on this video. this eagle was a bald eagle i think but i suppose the same max weight would apply to WTEs, too.
what was amazing was to see how the eagle rowed 'breast stroke' with unchanging pace over a rather long distance. it didn't seemed to be tired at all even after it got up to dry land.
According to the Stewards of the Upper Mississippi River Refuge, 2015/2016 will be the third year that this trio of Bald Eagles has been together. For the first time it was possible to document their activities: "We have been watching them work on the nest for a month, now they are ready for the next stage.” (Source: Youtube video description.) Many thanks to forum member b.h-p for this interesting link.
Upload: Stewards of the Upper Mississippi River Refuge, 3 February 2016
And yes, White-tailed Eagles do it too. Some information on this subject, compiled last summer, below.
Re: Talk about
Posted: February 6th, 2016, 12:24 am
Would you see the third eagle? A note on alternative family structures
Would we notice a third parent bird in or around a White-tailed Eagle nest where we usually expect to see a pair? Experiments show that it´s even possible to overlook a gorilla... “Cooperative groups may be overlooked in raptors (...) for several reasons:
(1) there are few raptor studies involving banded birds;
(2) many species have large territories, making it difﬁcult for observers to see all individuals residing in the territory;
(3) many raptors are sensitive to disturbance and will avoid their nest or behave abnormally when a human observer is present; and
(4) distance between territories may make it difﬁcult to monitor a large number of nests in enough detail necessary to detect cooperative behavior. In addition, because most raptors are thought to be monogamous, additional birds may be viewed by casual observers as transients and thus not recorded.” (Kimball et al 2003)
The most creative raptor concerning family structures seems to be the Madagascar fish eagle: “35 percent of the known breeding population exhibits cooperative breeding strategies”. (For more information see e.g.: Population status of the Madagascar Fish Eagle Haliaeetus vociferoides in 2005–2006, G. Razaﬁmanjato et al. or The Eagle Watchers/Madagascar Fish Eagle, Ruth E. Tingay.) There are also some reports of Bald Eagle (Garcelon et al. 1995) and other eagle breeding trios. Gunnar Bergo, for example, describes such a group of Golden Eagles in Norway: “All three birds in the 'trio' took part in all breeding activities, but only two were sexed with certainty.”
Occasionally the White-tailed Eagle cooperates in a similar way. As yet I found these sources:
Scotland: “The establishment of the reintroduced population was slow at first. No eggs were produced until 1983 when one of two breeding attempts involved a trio (a pair with a second female); both clutches were damaged as a consequence. Such trios have since been observed in the Scottish population several times, and may persist for several years.” White-tailed Eagle. John A. Love in: The Birds of Scotland, 2007
Unspecified: “Some eagles breed in polyandrous trios (one female with two males); this occasional behavior has been reported for some white-tailed sea eagles and Spanish imperial eagles”. The Eagle Watchers: Observing and Conserving Raptors around the World edited by Ruth E. Tingay and Todd E. Katzner, 2010
Ireland: “White-tailed Eagles have successfully hatched chicks across four counties in Ireland. Eight pairs of White-tailed Eagles have nested and laid eggs with five nests successfully hatching chicks in counties Clare, Cork, Galway and Kerry. In the last few weeks’ chicks hatched in nests on Lough Derg at Mountshannon, Co. Clare, at Glengarriff in West Cork, and in Killarney National Park, Co. Kerry. Pairs also successfully hatched chicks at a nest in Co. Galway for the first time and at another site in Kerry. Three other pairs nesting in Kerry failed to hatch successfully. Interestingly two of these ‘pairs’ were made up of trios: two males and a single female at one site and two females and a male at another, both in Kerry!” Press release. Golden Eagle Trust, 2 June 2015. Update on the Kerry breeding trio, 20 September 2016 https://www.facebook.com/permalink.php? ... 4808950774
Update, 16 August 2017. UK/Scotland. Also interesting: “A male sea eagle has successfully raised chicks from two different nests in East Scotland for the first time ever in Scotland. The eight year old male sea eagle, known as Turquoise Z, has been travelling between Angus and Fife visiting two nests, more than 28 miles apart, and raising chicks with two different females.” Read more at: http://www.fifetoday.co.uk/news/environ ... -1-4532872
Bergo, G. Territorial behaviour of Golden Eagles in Western Norway. Brit birds 80: 361-376, August 1987
Drew, T., Vo, M. L., & Wolfe, J. M. (2013). The invisible gorilla strikes again: Sustained inattentional blindness in expert observers. Psychological Science, 24(9), 1848–53
Garcelon, D. K., G. L. Slater, C. D. Danilson, and R. C. Helm. 1995. Cooperative nesting by a trio of Bald Eagles. Raptor Research 29:210-213
Kimball R. T., Parker P. G., Bednarz J. C. 2003. Occurrence and evolution of cooperative breeding among the diurnal raptors (Accipitridae and Falconidae). Auk 120, 712-729
Edit: The third eagle in the Latvian nest in the picture above was added by me, but theoretically it can happen ... Stay vigilant and question everything ;-).
Re: Talk about
Posted: February 6th, 2016, 4:47 pm
Update: Looduskalender Multi-Camera View
Urmas Lett created this feature last year. Click on the link below to see at a glance what´s happening at all monitored places. Click any of the thumbnail images to view the corresponding camera. The images should refresh automatically after 2 minutes. If that doesn’t work, try the "Refresh" button of your web browser.
How eagles went from worshipped ‘kings of the skies’ to victims of rat poison
“Say the word ‘eagle’ and the associations that come to mind are ‘soaring’, ‘majestic’, ‘eagle eye’ and ‘king of the skies’. (…) For centuries, eagles were respected for their strength and endurance as a predator. They were seen as a form or messenger of immortal Gods or royalty – from Zeus in Greek mythology to his Roman counterpart Jupiter, from Norse mythology to Celtic folklore, from Roman emperors to Catholic kings, and the Torah.” (Sanya Khetani-Shah, BirdLife International) Read more: http://www.birdlife.org/europe-and-cent ... rat-poison
Re: Talk about
Posted: February 13th, 2016, 4:24 pm
Place names where eagles dared
After Ragnarök. By Emil Doepler (1855-1922), public domain
Evans, R.J., O'Toole, L. and Whitfield, D.P. (2012). The history of eagles in Britain and Ireland: an ecological review of place name and documentary evidence from the last 1500 years. Bird Study 59: 335-349.
I hope you saw the right bird this morning. Whatever bird you saw first, "it is sure to foretell that you are a person that loves nature and that birds will be a part of your future for years to come and that is always a good omen!" Read more at Wild Birds Unlimited: http://blog.wbu.com/2012/02/14/valentin ... the-birds/
The raptor exhibited signs of lead poisoning. “This fate is terrible for affected eagles, but is also completely preventable. If you deer hunt, please check out copper bulllets. They come in all sizes, and are an equally good if not better bullet. They cost slightly more, but isn't an eagle's life worth it? Learn more about non-lead ammo here: http://www.huntingwithnonlead.org."
Source, story and pictures: Wildwoods/Facebook: https://www.facebook.com/media/set/?set ... 035&type=3
A study shows that lead in hunting bullets is dispensable: Performance of Lead-Free versus Lead-Based Hunting Ammunition in Ballistic Soap. By Felix Gremse, Oliver Krone, Mirko Thamm, Fabian Kiessling, René Hany Tolba, Siegfried Rieger and Carl Gremse, published 16 July 2014, Plos One http://journals.plos.org/plosone/articl ... ne.0102015
Re: Talk about
Posted: February 16th, 2016, 5:28 pm
EU: Failure to ban toxic ammunition putting bird lives at risk
According to the Food Standards Agency (UK), "people who frequently eat lead-shot game, particularly small game, should cut down their consumption. This is especially important for vulnerable groups such as toddlers and children, pregnant women and women trying for a baby, as exposure to lead can harm the developing brain and nervous system." Read more: http://www.food.gov.uk/science/advice-t ... -with-lead
"Lead is a particularly soft metal. (...) It is easily eroded and oxidized, and it becomes more toxic
and contaminant in acid environment." Photo: Public domain via Wikimedia Commons.
Lead poisoning in White-tailed Sea Eagles: Causes and approaches to solutions in Germany. By Oliver Krone, Norbert Kenntner, Anna Trinogga, Mirjam Nadjafzadeh, Friederike Scholz, Justine Sulawa, Katrin Totschek, Petra Schuck-Wersig and Roland Zieschank. PDF available via Google
Global lead advice & support service (GLASS). Goal: “Working to eliminate lead poisoning globally and to protect the environment from lead in all its uses: past, current and new uses.” https://www.lead.org.au/fs/fst1.html
Interesting new book: The Most Perfect Thing: Inside [and Outside] a Bird's Egg by Tim Birkhead
“The Most Perfect Thing is about how eggs in general are made, fertilized, developed, and hatched. The eggs of most birds spend just 24 hours in the oviduct; however, that journey takes 48 hours in cuckoos, which surreptitiously lay their eggs in the nests of other birds. (…) Birkhead uses birds' eggs as wondrous portals into natural history, enlivened by the stories of naturalists and scientists (...)." Source: http://www.buteobooks.com/product/14610 ... rslib.html
Another interesting question: “What is it like to be a bird?” According to Birkhead, after decades of watching and studying birds he “began to realise that there was much more going on in a bird’s brain than we give them credit for. Birds see better and differently from us; their sense of smell, touch and taste are much better than we have so far imagined.” Lern more: http://bird-sense.com/the-book/
Artist: G. van Raalten. Source: Naturalis Biodiversity Center/Wikimedia Commons
About the author: “Tim Birkhead is a professor at the University of Sheffield where he teaches animal behaviour and the history of science. He is a Fellow of the Royal Society of London and his research has taken him all over the world in the quest to understand the lives of birds. He has written for the Independent, New Scientist, BBC Wildlife.” (Amazon) Read more about Tim Birkhead http://bird-sense.com/author/
Literature search tip: KVK (Karlsruhe Virtual Catalog). Book search interface for more than hundreds of million books and serials in library and book trade catalogs worldwide. http://www.ubka.uni-karlsruhe.de/kvk_en.html
Re: Talk about
Posted: February 21st, 2016, 7:37 pm
Raptor: A Journey Through Birds by James Macdonald Lockhart – review
“In the opening chapter of Raptor, the author describes a Neolithic chambered tomb found on South Ronaldsay, Orkney. Among the remains of 340 people were the bones of 35 birds, two thirds of which belonged to white-tailed eagles. Archaeologists have concluded that the human corpses had been exposed so that they could be stripped of their flesh.” Read more: http://www.theguardian.com/books/2016/f ... d-lockhart
Author James Macdonald Lockhart: "My eyes are always quivering for birds of prey. I have always been turned to their presence". Source: HarperCollins
“Reassuring to know all 4 chicks hatched last year are alive, well and exploring the country. Better still we also know that the 2014 hatched Mountshannon chick was back on the Little Brosna callows in Jan 2016, the same area she spent last winter.” Golden Eagle Trust/Facebook, 23 February. Read more: https://www.facebook.com/pages/Golden-E ... =ts&v=wall
Eagle-TV Denmark: DOF preapares for upcoming nesting season
“Danish Ornithological Society/BirdLife Denmark (in Danish: Dansk Ornitologisk Forening - DOF) is a private society working for the protection of birds and nature as well as the procurement of knowledge on birds” (source: dofbasen.dk). The nest is located on Lolland, the fourth largest island of Denmark.
Denmark: The last season was very interesting – both eggs were destroyed by a marten in the early morning of March 20th (see video below). The clutch was replaced about ten days later. In early June one of the chicks was injured by the talon of a parent bird, even though the adults usually carefully clench their talons into balls in the nest (video: https://www.youtube.com/watch?v=PCWQ4V9 ... re=youtu.b). The eaglet survived, and the siblings left the nest around August 20th.
A marten destroys the first clutch. Video by DOFBirdLife
Here some general information on the subject and details about the Danish eagle family in English:
Replacement clutches in eagles – some notes and sources (see 23 April 2015)
Video documentation: Loss of the first clutch and laying of a replacement clutch in a White-tailed Eagle nest in Denmark (see 24 April)
"Thus a conflict there is not every day: conservationists against environmentalists; Greenpeace against Naturschutzbund Germany (NABU). The problem: The Greenpeace offshoot Planet Energy wants to build wind turbines in the Weser valley near Rinteln. But in that very valley in the district of Schaumburg broods a pair of eagles, therefore comes fierce headwind from NABU"