Week 1:  August 1-7, 2005

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We tend to think of May and September as the peak periods for warbler migration.
Yet it was this week, on August 6, that we set a new site record for the highest number
of warbler species banded in one day, with 11.  See if you can identify all of the species
(and plumages) above ... including the impostor.  The answers are below, at the end of
the weekly summary.  (Photos by Marcel Gahbauer, composition by Marie-Anne Hudson)


# birds (and species) banded 70 (22) 70 (22) 803 (66) 1724 (80)
# birds (and species) repeat 2 (2) 2 (2) 247 (18) 425 (28)
# birds (and species) return -- -- 29 (6) 31 (7)
# species observed 74 74 142 157
# net hours 71.5 71.5 1726.4 2700.9
# birds banded / net hour 97.9 97.9 46.6 63.8

Note: table does not include nocturnal banding (owls)

Bander-in-charge:  Marcel Gahbauer
Assistants:  Helen Garland, Gay Gruner, Marie-Anne Hudson, Betsy McFarlane, Chris Murphy

Notes:  At first it felt strange to declare the fall season underway on August 1, but over the past week we have found plenty of evidence that migration has indeed begun.  While the greatest number of species seen on any day this week was 42, a total of 74 were seen, with many of them just passing through on one or two mornings.  This is already more species than were seen in all of July!

One of the most noticeable migrations this week was that of the Yellow Warblers, which peaked on Wednesday morning with roughly 30 in the area.  Also noteworthy were the flocks of juvenile Baltimore Orioles, sometimes 6-8 of them sharing the same branch of a large tree.  Though most were present in small numbers, it was equally impressive to have 13 species of warbler present on August 6.  With the addition of three others the next morning, we ended up with 16 warbler species for the week, including MBO's first ever Bay-breasted.

The banding season got off to a great start with 21 birds in a single hour on August 1.  Subsequent efforts on August 3 and 6 produced somewhat more modest numbers, but all the same we're very happy to have already banded 69 birds in our first week, at a rate of nearly 100 birds per 100 net hours (double our spring average).

Top row (left to right):  Nashville Warbler (juv), Common Yellowthroat (AHY male),
Yellow Warbler (AHY female), Black-throated Green Warbler (AHY male)
Middle row (left to right):  Tennessee Warbler (HY unknown sex), Black-and-white Warbler (AHY
female), Northern Waterthrush (AHY unknown sex), Black-throated Blue Warbler (HY female)
Bottom row (left to right):  Wilson's Warbler (HY male), American Redstart (AHY female),
Swamp Sparrow (HY unknown sex), Ovenbird (juv)




2002- The Migration Research Foundation Inc.