Pictorial_Highlights

PICTORIAL HIGHLIGHTS, WEEK OF 5/29/01-6/03/01

We had to put up with unseasonably cool temperatures, rain showers and breezy conditions all morning on 6/3, the last official day of the spring banding season at Powdermill. Birds were few and far between, and for the first day since 4/20, we failed to band a single wood warbler of any kind!

We did catch two more Yellow-bellied Flycatchers, both of which were SYs showing more typical molt limits (see Pyle's [1997] fig. 146C) than the YBFL pictured below on 5/31. The photo did not turn out to be as well-focused as we hoped, but the molt limits are nonetheless clearly visible between retained brownish juvenal primaries 1-3 and the much darker molted outer seven primaries; retained juvenal secondaries 1-4 and molted inner secondaries 5-9; retained outer juvenal greater coverts 1-4 and molted greater coverts 5-10; retained outermost median covert and the molted inner median coverts. Note, also, the very brown, retained juvenal primary coverts.

Partly cloudy and mild early AM, becoming windy and warm by afternoon on 6/2. A return to very low banding capture rates, but a nice diversity of birds was caught ranging from Hairy Woodpecker to Northern Rough-winged Swallow to Golden-crowned Kinglet to Mourning Warbler and Lincoln's Sparrow.

The Hairy Woodpecker, a hatching year (HY) male, had an extensive red juvenal crown patch (females have black or very limited red juvenal crown feathers). During the bird's first prebasic molt later this summer, its red juvenal crown will be lost and a red nuchal patch (on he back of the head) characteristic of "adult" males will molt in.

We banded two female Mourning Warblers, which differed greatly in appearance--one was an ASY with a full, sharply delimited gray hood (top left), while the other was an SY with partial gray hood mixed with yellow and green (top right). Closeup photos of their wing plumage show the uniformly fresh, brightly colored and edged coverts and alula on the ASY female (bottom left) compared to the more worn, brownish primary coverts and two large alula feathers (the alula covert was molted) of the SY bird (bottom right).

The Golden-crowned Kinglet was quite unusual, because it was one-third of the way through its prebasic (i.e., post-breeding) molt. It had a wing molt score of 36 out of a possible 95 (primaries 1-5 freshly molted, p6 1/3 grown, p7-10 unmolted; secondary 1 2/3 grown, s2 in full sheath, s7 freshly molted, s3-6 and s8-9 unmolted; see photo). The bird, a female, had no trace of a brood patch, and, because her molt probably began 2-3 weeks prior to her capture on 6/2, at a time when most GCKIs are in the early stages of nesting, we suspect that, for some reason, she did not attempt nesting at all this year.

Because of wind, the threat of rain, and, shortly thereafter, the reality of rain, banding effort was very limited on 6/01. Although only 15 birds were banded, due to the minimal banding effort, this actually represented a substantial increase in our capture rate compared to yesterday (which isn't saying very much!). We recaptured a female Blackpoll Warbler that we forgot to photograph when she was originally banded yesterday, enabling us to correct that oversight and thereby provide you with a companion photograph to our portrait of the male BLPW (see Past Pictorial Highlights for the week of 5/23; also, to compare with our possible hybrid female Bay-breasted X Blackpoll Warbler).

Nets were frozen shut early AM on 5/31! As a result, banding was not begun until well after sunrise, and this undoubtedly contributed to our logging the lowest capture rate so far this spring. Among just a dozen birds banded were two migrant species--a female Blackpoll Warbler and a Yellow-bellied Flycatcher.

As we said before, the YBFL is one of our favorite species (it is also THE favorite species of a good friend of ours who, based on his studies of its nesting ecology, thinks "Moss Tyrant" is a more appropriate common name). Anyway, we think it rates another picture!

Today's YBFL was an SY (second year) bird (i.e., hatched in the calendar year 2000) based on wing molt limits. In the picture above, you can see a few retained (brownish) juvenal lesser coverts on the bird's "shoulder" or bend of the wing. Also visible are a retained median covert (brownish with a white tip) in the next row of coverts, and, in the bottom row, four retained outer greater coverts (also brownish with white tips). This bird apparently had undergone a very limited first prealternate wing molt on its wintering grounds. All of its flight feathers were retained juvenal, except for the inner four secondaries (this molt limit is barely visible in the photo just below the molted, yellowish tipped inner greater coverts). The bird's wing plumage closely resembled Fig. 146A in Pyle's (1997) Identification Guide to North American Birds.

We had a few more birds to band on 5/30 than yesterday, and proportionately higher species diversity on 5/30. Migrants banded included Philadelphia Vireo, Wilson's Warbler, and Northern Waterthrush. An ASY male American Redstart was only our second to band this spring in this plumage.

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