Geese are surprisingly complicated for birds that seem to only swim and chase after any children with bread crusts. Even one of the most familiar North American birds may not be exactly what it seems. While this looks like a Canada Goose (Branta canadensis), there is a fair chance that current ornithologists would label it as a Cackling Goose (Branta hutchinsii). Slightly smaller and with more petite features than the Canada Goose, the Cackling Goose has had a long wait to be recognized as a separate species. At first, it was just assumed that some Canada Geese were smaller than others. After a while, researchers noticed that there seemed to be distinct size differences in the populations, determining that the smaller geese must be a subspecies of the Canada Goose. Finally, in 2004, the Cackling Goose was represented as its own species by the American Ornithologists’ Union, and as other experts began to agree, populations of these closely related geese have been marked as either the old or new species. The birds can still often be seen together, which makes for some great size comparisons, but they can also be distinguished by the proportions of their beaks. Which do you think this specimen is?

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Can you identify the species in these photos from Malheur National Wildlife Refuge? Follow @nprskunkbear and the hashtag #FlockupyMalheur on twitter for fun facts about these birds.

Most of the images come from Flickr user Dan Dzurisin - he has lots of amazing wildlife photography on his page. The landscape comes from Flickr user Mathew Foster.

Other images:

Why is the refuge occupied by armed militants? Read all about it here.

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John James Audobon - The Birds of America

The Birds of America is a book by naturalist and painter John James Audubon, containing illustrations of a wide variety of birds of the United States.

Printed between 1827 and 1838, it contains 435 life-sized watercolours of North American birds, all reproduced from hand-engraved plates, and is considered to be the archetype of wildlife illustration.

https://www.audubon.org/birds-of-america

Feathers

Found only on birds, feathers are some of the most complex integumentary (skin) structures found in vertebrates.

There are two primary types of feathers: flight and down. Some birds, such as peacocks and birds-of-paradise, also have display feathers.

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Flight feathers come in two categories of their own: remiges (wing feathers), and rectrices (tail feathers). These strong feathers are what allow most birds to fly. They have strong midline ridges, called the shaft (or rachus). The rachus is mostly covered in the fluffy-but-structured extensions, what most people think of as the “feather”, called the vane. At the bottom of the rachus, below the vane, is the bare quill (or calamus). Each extension on the vane is covered in many hooks and hooklets (also called barbs and barbicels), which is what birds are putting back into place when they preen - gotta keep everything in order to fly well!

Down feathers don’t have the hooks or the rachus of the flight feathers. There are many types of down feathers, but all of them serve the same basic purpose, which is temperature regulation. They trap air close to the bird’s body, which insulates it from the cold. When a bird puffs up in the middle of winter, it’s creating a bigger insulating layer to trap body heat, so that it doesn’t cool off as quickly.

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To replace their feathers on a regular basis (to remove damaged or correct for lost feathers), birds undergo a process called moulting. Depending upon the species, this can happen all at once, be staggered over the course of a year, or happen gradually over several years. Many species undergo moulting during breeding season, to show off their flashy plumage.

Moulting is regulated by the pineal gland and circadian rhythms in most birds, though in pet birds, a somewhat-constant slow moult (punctuated by one or two “big moults” a year) is found, as a result of artificial lighting.

Nouveau Larousse Illustre. Claude Auge, 1898.

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I wanted to share this awesome, brand new bird poster from the artists at Pop Chart Lab with you all. This large 39″ x 27″ poster features a stunning 740+ species of native and introduced birds found in North America. They are drawn *somewhat* to scale and grouped by family. Pop Chart Lab is offering 5% off for @becausebirds​ followers with the code: BBirds5

Birds of North America The Complete Collection

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If there ever was a top-ten of the most gorgeous creatures on Earth (or, for that matter in the Universe :) ), the birds-of-paradise would definitely have to be shortlisted. There’s a great documentary by David Attenborough about these exquisite birds, you can watch it here.

Drawings from Histoire Naturelle des Oiseaux de Paradis et des Rolliers, suivie de celle des Toucans et des Barbus by François Levaillant and Jacques Barraband.