Blog Birding #73
by Nate Swick
An informative piece from Gavin Leighton at Boom Chachalaca on why birds took to the air in the first place:
One of the major hypotheses for why flight evolved capitalizes upon observations of contemporary birds. Since many birds spend significant time in the trees, the arboreal hypothesis of flight argues that wings evolved to help birds navigate from tree to tree. The progression of evolution begins with individuals living primarily arboreal lifestyles (i.e. foraging in trees and spending most of the time in tree canopies). Such a lifestyle would put selection pressure on individuals to move from tree to tree without having to return to the ground first. These observations led to the arboreal theory.
Radd Icenoggle shares some photos and video of an American Dipper gathering nesting material:
Short film and images of American Dippers gathering moss for their nest, which is located underneath a bridge that spans rattlesnake Creek in Greenough Park. Notice that the birds are consistently dunking the nesting material, namely moss. The wetting is thought to keep the moss alive and, therefore, more pliable. The American Dipper nest is ideally placed under a cliff overhang or bridge that is above the home range stream. The nest itself is a large (~1 foot), mossy dome, which consists of an outer shell of moss and grass, and interior cup is made of grass, bark stripes, and leaves. The entrance of the nest is towards the bottom of the dome. Both sexes are responsible for the nest construction, although the female chooses the nest location.
From Scientific American, a really thorough piece on the wonders of tubenose physiology:
It used to be thought that the petrel nasal tube acted as a nozzle allowing the birds to squirt stomach oil as a defensive measure. In fact, the birds squirt oil defensively through the mouth (though, when handled, they do sometimes drip oil from the nasal tube). This oil-squirting behaviour is most famously practised by fulmars (Fulmarus) but other members of the petrel group Fulmarini (all of which nest out in the open, rather than in burrows like many other petrels) do it as well.
At 10,000 Birds, Walter Kitundu offers some photos of birds doing things you won't find in your field guide:
When you spend a lot of time outdoors you get to see strange things happen. Birds are consumate improvisors and they are always open to the demands of the moment. So while they may have regular habits, weird things do occur and the field guide will only help you to a point… the rest is just watching. Here now, with brief captions, are some oddities.
The irreverent and entertaining Seagull Steve of Bourbon, Bastards and Birds is Arizona dreaming:
For much of the time of my work stint we stayed at the research station Florida Canyon, where birds like Black-capped Gnatcatcher and Rufous-capped Warbler lived within walking distance, and a Ring-tailed Cat lived in our attic. Yes, it was the best roommate ever, thank you very much. Our survey sites were, not coincidentally, some of the best birding spots in the area...Miller Canyon, Carr Peak, Madera Canyon, the Nature Conservancy's Patagonia reserve....you get the picture. One gets to feel a bit smug to essentially just go birdwatching in areas people pay large sums of money just to get to. Part of the charm of the area (granted, this is arguable) is the vast numbers of birders you will meet, and the number of homes and yards that have been opened up to birders simply so we can stare at the birdfeeders...I thought it was quite funny to be doing a point count next to the Patons' legendary backyard, counting Violet-crowned Hummingbirds for SCIENCE!