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Summer 2007 Notes and
Highlights
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- During the second half of
summer, our banding station operated on 23 days. We banded 679 birds of 55 species
and processed 183 recaptured birds. Our total effort (1,820 net hours) was similar to June, when less than half
as many (274) birds were banded, so the capture rate during the latter part of
the summer period
more than
doubled to 37.3 new birds per 100 net hours. Locally
breeding adults (usually in heavy molt) and young (Hatching Year) birds
comprised most of our
catch. And, except for
Red-eyed Vireo and Cedar Waxwing, HY birds dominated our totals for
most species.
The most commonly banded species during the second half of summer were American Redstart (96), Gray Catbird (89), Cedar Waxwing (63), Common Yellowthroat (46), Red-eyed Vireo (35), Hooded Warbler (34), Wood Thrush (32), Song Sparrow (28), Scarlet Tanager (20), and Veery (19). Our total for the period also included a number of early "fall" migrants, such as Least Flycatcher, Yellow Warbler, and Northern Waterthrush, distinguishable by their visible fat deposits. Our best banding days occurred at the beginning (7/5: 49 birds of 11 species) and the end of the period (8/2: 48 birds of 21 species). The former was greatly helped by an influx of Cedar Waxwings; the latter, by Gray Catbirds and Red-eyed Vireos.
Overall, the summer 2007 total of 953 birds banded was above (but not statistically so) our long-term average of 733, but it was well below our maximum summer banding total of 1,500 recorded in 2004. Similarly, the summer 2007 species total of 57 was close to the long-term average (~59) but well below the highest count of 78 species in 1998.
Most species were banded in statistically average numbers this summer (i.e., within one standard deviation of the long-term, 1961-2006, mean). No species were below average, but the following 17 species (out of 57 examined) were > 1 S.D. above the long-term average: Ruby-throated Hummingbird, Least Flycatcher, Veery, Wood Thrush, Gray Catbird, Cedar Waxwing, Chestnut-sided Warbler, Magnolia Warbler, Black-throated Blue Warbler, Cerulean Warbler, American Redstart, Kentucky Warbler, Common Yellowthroat, Hooded Warbler, Scarlet Tanager, Northern Cardinal, and Red-winged Blackbird. Fifteen species with long-term summer season averages > or = 1 were missed (e.g., Eastern Wood-Pewee, Great Crested Flycatcher, Blue-winged Warbler, Chipping Sparrow, and both cuckoos); conversely, we banded nine species with long-term averages <1 (e.g., Swainson's Thrush, Worm-eating Warbler, and Orchard Oriole). A Cooper's Hawk banded on July 17 was an addition to our all-time summer banding list, which now stands at 122 species. Click here to see all our summer 2007 totals compared to their associated long-term averages, minima, and maxima.
- We
thank Mary and Alex Shidel, Pam Ferkett, Matt
Shumar, Sally McDermott, Annie Lindsay, Mike Allen, Trish Miller, and Jean Rothe for their help with
banding in July.
- WARNING!--There are so many
photo highlights we had to split this update into two pages!
- Many adults are in heavy molt
in July as they begin to replace their entire plumage. Because of
the demands of nesting, some of these birds, especially SY birds whose
flight feathers are older, are in dire need of
molt! This Indigo Bunting (SY female) exemplified the need for
molt! At the time of capture (July 5th), she still had a
brood patch and had not begun molting, but, as you'll read below, other
birds with
shorter nesting seasons were already doing so.
- American Redstarts are one of
the earliest species to undergo their prebasic (i.e., post-breeding)
molt. An SY-M
AMRE (top photo below), had a molt score of 62 (out of 90)
on July
17th, compared to a fresh AHY male (bottom photo below) which already
had completed its molt (molt score = 90) as of August 5th.
Although we can't be sure, the early date of its molt completion
suggests that it, too, was an SY-M (all traces of its female-like SY
plumage having been replaced), because this age class generally has
much lower breeding success than adult (ASY) males.
- We captured several
molting Chestnut-sided Warbler adults this month, including these two
SY
females with molt scores of 16 and 31, respectively.
