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Birds in the News / Re: News: Bird Science
« Last post by Jazzerkins on Today at 18:35 »
Interesting article.  I look forward to more of their findings in regards to the shape of eggs of different types of birds.
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Radisson's Green Girl who has nested at Weber has 3 girls and 1 boy at banding yesterday.
Bev will give more details when she has a moment .
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Bell Tower has 2 girls and the male maybe Radisson's chick from 3 years ago.
Bev will give more details when she has a moment .
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Birds in the News / News: Bird Science
« Last post by The Peregrine Chick on Today at 13:32 »
Here's a cool article .... if you want to see the photos, click on the link at the bottom

Why Do Bird Eggs Have Different Shapes? Look to the Wings
In the most comprehensive study of egg shapes to date, scientists say that the best predictor of long or pointy eggs is a bird’s flying ability.

By Steph Yin / Science / June 22, 2017

Owls’ are spherical, hummingbirds’ are elliptical and sandpipers’ are pointy.

All bird eggs have the same function — to protect and nourish a growing chick. But they come in a brilliant array of shapes. This variety has puzzled biologists for centuries. Now, in the most comprehensive study of egg shapes to date, published Thursday in Science, a team of scientists seems to have found an answer.

The researchers cataloged the natural variation of egg shapes across 1,400 bird species, created a mathematical model to explain that variation, and then looked for connections between egg shape and many key traits of birds. On a global scale, the authors found, one of the best predictors of egg shape is flight ability, with strong fliers tending to lay long or pointy eggs.

“This paper is remarkable because it creates a wonderfully unified theory for the variety of egg shapes we see in nature,” said Claire Spottiswoode, a bird ecologist at the University of Cambridge and the University of Cape Town who did not participate in the research.

In the new study, the authors conducted a multistep investigation that brought together biology, computer science, mathematics and physics. They first wrote a computer program, named Eggxtractor — who says scientists have no sense of humor? —, that classified eggs based on their ellipticity and asymmetry. Elliptical eggs are elongated and round on both ends, like cucumbers, and asymmetric eggs are pointier on one end, like mangoes.

With Eggxtractor, the researchers plotted nearly 50,000 eggs, representing all major bird orders, from a database of digital images by the Museum of Vertebrate Zoology in Berkeley, Calif.

“We could see then that egg shapes varied from spherical, to elliptical, to very pointy, to almost everything in between,” said Mary Caswell Stoddard, an assistant professor of ecology and evolutionary biology at Princeton University and the lead author of the study.

Next, the researchers attempted to answer how eggs might acquire varying shapes. Rather than looking at the shell, as one might expect, they focused on the egg’s membrane (the film you see when peeling a hard-boiled egg), which is essential to the egg’s shape.

The scientists identified two parameters that could influence egg form: variations in the membrane’s composition and differences in pressure applied to the membrane before the egg hatches.

By adjusting these two parameters, “we were able to completely recover the entire range of observed avian egg shapes” — a good test of the model, said L. Mahadevan, a professor of applied math, biology and physics at Harvard University and an author of the study.

Finally, the researchers looked into why egg shapes might be so spectacularly diverse. One popular hypothesis centered on nest location: Cliff-nesting birds, it was thought, lay pointy eggs so that if the eggs are bumped, they spin in a circle rather than rolling off the cliff. Another suggested that birds lay eggs in shapes that pack together best in different-size clutches.

But when the authors related egg shape to these and other variables, they were surprised to find that none of them fit on a global scale (though they may still play important roles on smaller scales). Instead, egg shape was strongly correlated with a measure of wing shape, called the hand-wing index, that reflects flight ability.

So what connects flight to egg shape? In general, birds want to pack as many nutrients as possible into their eggs. But, in order to fly, they must maintain sleek bodies — meaning their eggs can’t be too wide.

Common murres, for instance, are fast, powerful fliers and have asymmetric eggs, as do least sandpipers, which migrate long distances.

Wandering albatrosses are one of the most far-ranging fliers — some have been known to circumnavigate the Antarctic Ocean three times in a year — and have elliptical eggs.

Eastern screech owls rarely move beyond their small territory, where they tend to fly in short, low-powered glides, and have almost spherical eggs.

“Perhaps, evolutionarily, birds stumbled upon this very natural, geometric solution, which is to increase the ellipticity and asymmetry of their eggs,” Dr. Mahadevan said, since doing so allows for greater volume without increasing girth. This explanation requires further research, he added.

Ultimately, this study shows that “we can challenge old assumptions,” Dr. Stoddard said. ”In something as familiar and common as a bird egg, we are still discovering new truths.”


Source:  https://www.nytimes.com/2017/06/22/science/bird-eggs-shapes-flight.html
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Banding should take place on Friday June 29th at U of A

Radisson's Green Girl who has nested at Weber has 3 girls and 1 boy at banding yesterday.
And Bell Tower has 2 girls and the male maybe Radisson's chick from 3 years ago.
Bev will give more details when she has a moment .
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Logan Peregrines / Re: Logan - 2017 / Hart & Jolicoeur
« Last post by photosbydennis on Today at 08:20 »
Good morning to all the Peregrine Phanatics...as your well aware banding of the Logan and West Wpg chicks has taken place July 18th.
Couldn't ask for a better Nice Fathers Day present !

Banding Galleries have been created and more photos will be added in the days to come.

Stop by and have a look at the kids close up http://www.pbase.com/photosbydennis/peregrines_2017

Cheers !
Dennis
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Good morning to all the Peregrine Phanatics...as your well aware banding of the Logan and West Wpg chicks has taken place July 18th.
Couldn't ask for a better Nice Fathers Day present !

Banding Galleries have been created and more photos will be added in the days to come.

Stop by and have a look at the kids close up http://www.pbase.com/photosbydennis/peregrines_2017

Cheers !
Dennis
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New story from North Dakota - http://www.kvrr.com/2017/06/20/audubon-dakota-monitoring-area-peregrine-falcons/

Nothing wrong with the reporter but I'm not sure the Audubon Dakota rep knows much about peregrines based on his replies.  Perhaps he was pitch-hitting for the person who is the expert.  These are the folks who have successfully/unsuccessfully run the camera in Fargo the last few years.  I haven't ever been able to get them to respond to queries about the birds, nest, cam or anything so I'm afraid I don't have any knowledge of them or their operations ... well other than they are not good at responding to information requests and in this case, don't seem to particularly invested in finding out if Annie is injured or not - even if they can't do anything about it.  But maybe I'm being too harsh and they are working on it as we speak ... time will tell I guess.
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West Winnipeg Peregrines / Re: Beatrix Rescued in Texas
« Last post by The Peregrine Chick on June 21, 2017, 13:53 »
June 2017 Update

She's still coming along - bumblefoot can be a tough nut to crack at times.  PWRC is looking at some supplemental therapies to help with the healing but so far, so good.  She's being a peregrine which is good.  Not out of tricks in our bag yet and she's miffed but not in any risk of anything at the moment ... other than getting bored :)

They have food for the moment and we just paid a couple of months work of medications, vet care and surgery.  For those wanting to support her care, you can hang onto your donation until we call for donations OR just include a note on your donation - there is space on all the donation pages online to include a note if you wish.  Or you can mail it in (don't forget to include a copy of the donation form). 

I have to update some information on the page, but Beatrix has her own page on our website if you want to check it out - the links to donate are at the bottom of the page.
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