Week 7:  September 12-18, 2005

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This week Nashville Warbler took over from Magnolia as the most abundant warbler
 banded.  Most of the Nashville Warblers passing through now are hatch-year birds,
but there are still occasional adults, such as the male shown above.  Overall it was
a great week for warblers, with 23 species observed and 20 banded, with as many
as 16 species caught on some days.  (Photo by Marcel Gahbauer)


# birds (and species) banded 426 (50) 1454 (65) 2187 (83) 3108 (90)
# birds (and species) repeat 63 (20) 216 (24) 461 (31) 639 (38)
# birds (and species) return 3 (2) 22 (7) 53 (12) 53 (12)
# species observed 90 123 149 163
# net hours 425.0 1898.2 3553.0 4527.5
# birds banded / 100 net hours 100.2 76.6 61.6 68.6

Note: table does not include nocturnal banding (owls)

Banders-in-charge:  Marcel Gahbauer, Barbara Frei, Marie-Anne Hudson
Assistants:  Pierre Bannon, Lina Bardo, Martin Bowman, Jean Demers, Sarah Fraser, Jacinthe Gregoire, Gay Gruner, Marie-Eve Jacques, Isabel Julian, Juliana Lisi, Andreanne Lortie, Barbara MacDuff, Francine Marcoux, Mike Mayer, Betsy McFarlane, Anthi Mimidakis, Julia Mlynarek, Chris Murphy, Robert Oligny, Julie Pépin, Majorie Poirier, Limoilou-Amélie Renaud, Clémence Soulard, Kim Tendland-Frenette

Quiz:  Can you identify the bird below by its tail?  Answer at the end of the weekly report.

Notes:  What a way to make up for a quiet week 6!  Last week's total was eclipsed before Wednesday morning was finished, and by the end of Thursday we had shattered our existing record of birds banded in a week by more than 50%.  With two more good mornings on Friday and Sunday, we ended up with 426 for the week, more than doubling last week's volume.  Along the way we also raised our single-day record twice, to 101 on Tuesday, and then 106 on Thursday.  Surprisingly, the big rush of birds came during above seasonal temperatures, with noon temperatures approaching 30 Celsius, higher still when factoring in the humidity.

Leading the way this week were six species which accounted for 53% of the birds banded:  White-throated Sparrow (44), American Goldfinch (40), Nashville Warbler (38), Magnolia Warbler (37), Red-eyed Vireo (35), and Palm Warbler (32, all but one of them Yellow).  The 50 species banded this week is also a one-week record for MBO, and is actually five species more than we banded in the entire 2004 fall season (though to be fair, that ran from mid-September to late October).

Significant bandings this week included Grey-cheeked Thrush, Cape May Warbler, Northern Parula, and Orange-crowned Warbler (each just banded once or twice previously), and Swainson's Thrush (13 individuals, compared to a previous total of just 8).  Also of note, an unusually late Yellow Warbler on Friday.

A busy week like this is only possible through the help of great volunteers.  Congratulations are due to Marie-Anne and Barbara for doing a great job as new banders-in-charge during the hectic first three days of the week, and especially to their Tuesday crew of Isabel, Julie, Martin, Jean, and Clémence for helping them manage the unexpected record volume of birds.  Likewise, special thanks to Marie-Eve, who carefully scribed for almost all of the birds during Thursday's record output.

While the volume of birds banded this week was more than double that of last week, the list of new species grew more slowly.  Newly observed for the season were Bald Eagle (first ever for MBO), Eastern Screech-Owl, Orange-crowned Warbler, and Grey-cheeked Thrush.  The latter two were among the five new species banded this week, along with Eastern Phoebe, Ruby-crowned Kinglet, and Lincoln's Sparrow.  Overall, the diversity of species observed this week was the highest yet, with a total of 90 species seen at least once, with 55 on Thursday and a near record of 62 on Sunday.  Among the week's birds were 23 species of warbler (including 18 on Sunday alone), all but three of which were banded.  In all likelihood we have just experienced the peak of this fall's migration, but we know that for many species the majority of individuals are yet to arrive, and expect to remain busy through the final six weeks of the season.

Quiz answer: it is a Swamp Sparrow!  The white tail feathers are reminiscent of a Slate-
coloured Junco, a species which is known to have hybridized with various other sparrow
species.  However, there are no documented records of Swamp Sparrows interbreeding with
 any other species, and in all other respects this bird looks like a typical Swamp Sparrow.
One of the many mysteries uncovered in the process of banding!  (Photo by Marcel Gahbauer)




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