I was asked the other day to elaborate about seeing the "rough-wing" on a Northern Rough-winged Swallow. This is one of those species names that only becomes obvious when you have the bird in the hand. (fortunately captured alive - and not shot and stuffed). On the outer edge of the last primary flight feather (P9), the tiny barbs show a "serration" pattern, that also distinguishes age and sex. On the adult male the fine comb-tooth barbs (hence "rough-wing") angle downwards, and in the adult female, they angle upwards. On juv males the barbs point about straight-out, and the juv female they are hardly there at all. Why, or what effect this might have on drag in flight I have no idea, but the the wing under magnification surely shows it's "rough" edge. ( Peter Pyle, "Identification Guide to North American Birds, Part 1", Figure 208, page 326.)
Today was cool and drizzly, with a low ceiling, and slight breeze, so miserable for me, but GREAT for migration! I had many waves of mixed migrants come through and passing overhead. AIt was a real good day of banding for a "corridor" station rather than a migrant trap. Biggest numbers were of Yellow Warbler (12) and Com Yellowthroat (9). Probably the best birds were a Least Flycatcher, and my 5th N Waterthrush this spring. Also seen - Olive-sided Flycatcher, and the Virginia's Rail continues to call nearby.
Banded today:
Dusky Flycatcher 2
Least Flycatcher
Warbling Vireo 3
House Wren
Gray Catbird
Swainson's Thrush 2 (FOS)
N Waterthrush
Yellow Warbler 12
Orange-crowned Warbler
Com Yellowthroat 9
Myrtle Yellow-rumped Warbler
MacGillivray's Warbler
Green-tailed Towhee
Lincoln's Sparrow 2
Red-winged Blackbird 2
Brown-headed Cowbird
Total birds today, 41 - My best spring day ever at CSR, also my last day banding at CSR this spring. :(
Happy Migration,
Steve Brown
Colorado Springs
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