Saturday, November 29, 2008

Why Do Turkeys Have Naked Heads? Blakeman on a Red-tail's Age. Plus Bambi and Thumper

Photo by Francois Portmann
I was curious about the Red-tail from the Portmann Hood. Here's what Red-tailed Hawk Expert John Blakeman had to say--

The bird is clearly a second -year Red-tail. The eye color is still a bit yellow, but with the hint of brown often seen in second-year birds. The tip-off is the length of the tail, which is way too short for a first-year bird. Lastly, the shading of the head and shoulders of first-year birds is identically dark chocolate brown. On this bird, the head is a bit tawny compared to the darker shoulders.
Clearly, a second year Red-tail. The horizontal bands of the belly are normal and usual at this age.

Sally of Kentucky sent in what I thought was a very good question.

I was chatting with the Tulsa folks about turkey vultures, their name and their head appearing similar to a turkey's and the usefulness of a "naked" head for a scavenger reaching up into the carcass for the "good stuff", and I started wondering aloud why then would a turkey also have a naked head? It’s certainly not because it is sticking its head up inside a carcass to eat. Camouflage in the high grasses when hiding from Donegal's camera? But other long-necked birds are not naked headed. Hmm. Any thoughts?


Well there are a few other species of long-necked naked headed birds like the Ibis and some Herons, but certainly many more who aren’t.

If you think about it though, many bare headed birds have a characteristic in common, that of brightly colored portions of skin that lump, bump, droop, and wrinkle. Though of course there are feather headed birds that have colorful skin that do have feathers at least on the tops of their heads like chickens.

During breeding season a turkey’s colorful patches become even more vividly colored for courtship purposes. And when a turkey is excited their entire skin tends to color as well. Which no doubt communicates something to other turkeys worth communicating.

I’d always wondered why Quicksilver my African Grey, had only teeny sparse pale feathers over portions of his face, particularly near his eyes. I thought perhaps it was because oil or fat wicked up the feathers and became a problem in some way in the wild where napkins weren’t particularly handy, until I noticed that when he was feeling affectionate and asked to be “tickled”, (a tickle for a Grey is a gentle rub with a finger on his neck and face), his skin took on a blush which was visible to the viewer due to the nearly naked portions of his face. Once again, the lack of feathers, allowed the skin to “communicate” with others.

There may be other reasons for the bald head adaptation as well but that’s what I’ve came up with for the moment.

Photo: Tanja Askani

R. of Illinois looked at these and remembered the blog discussion about just how intensely curious deer are about new smells.

Bambi and Thumper really do exist.

Photo: Tanja Askani

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