Saturday, June 11, 2011
While navigating the narrow, twisting road into Starr Ranch at some ungodly hour this morning, I realized with a start that it has been at least a year since I banded there. That is a pity, since banding provides a unique way to get intimate with birds while contributing to science and your own knowledge. It was a good morning of banding with 28 new birds banded, 13 recaptured, and 5 released unbanded.
This recaptured Common Yellowthroat had something funky going on with its head, with that orange coloration on the face...jokingly, we said that it beat some of the legitimate Orange-crowned Warblers for that title, but, it really was true!
Speaking of Orange-crowned Warblers, we banded six and recaptured one more. Many were hatch-year birds, easily recognized by their yellowish gapes, buff-tinged wing bars, and loose, fluffy feathering on the underparts. This individual boasted an unusual feature that also identified it as a youngster--a fault bar across the tail. These are formed when the growth of feathers is retarded or stopped during a period of food shortage. For some reason or another, this bird didn't have adequate food one day--maybe it was raining, and the parents couldn't gather enough food, or its nestmates trampled it underfoot and beat it to the food.
Speaking of growing feathers, this Hutton's Vireo was doing some hardcore molting. Note the contrast between the old outer primaries, which appear pale and tattered, and the new secondaries, which are darker and more pristine. Also, one feather (p2) is still in its sheath. This probably indicates that this bird is done breeding, since, as any bird will tell you, the simultaneous stresses of breeding and molting are not conducive to survival.
Speaking of, uh, birds, here's one of the Song Sparrows we handled today. With sedentary species such as this, we seldom catch new birds except for juveniles. This axiom held true today--we banded one new bird but processed four recaptures.
Speaking of brown, streaky birds, we banded two species of finches that often frustrate and foil birders: Purple and House. And, as this photo proves, classic field marks are not always reliable. Purple Finches are supposed to have straighter culmens than House Finches. Well, check out these birds. Sure, in direct comparison to the House Finch, the Purple may have a slightly straighter culmen, but, on a lone bird, I believe birders are universally screwed until someone invents a culmometer. Eastern birds are easier, with their more prominent white eyebrows, but note the considerably chunkier, bull-headed, grosbeak-like Purple (left) with the more svelte House (the opposite of left).
Speaking of identification problems, Black Phoebes pose none whatsoever (except the occasional confusion with Black-necked Stilts, but I won't dwell on that). Remember about that whippersnapper Orange-crowned with the cinnamon wing bars? Well, hatch-year Black Phoebes have them too. (As do Northern Rough-winged Swallows, California Thrashers, Pacific-slope Flycatchers, and many others...what's going on here?!) Also, check out those pale outer webs on the outer retrices, a characteristic shared with several other flycatchers (Eastern Phoebe, Vermilion...)
Speaking of outer retrices, it's late; I'm going to bed.