VCE closed out June on Mt. Mansfield under remarkably
consistent conditions -- wet, cool weather that challenged our ability
to run mist nets. Our team of 5 arrived on the ridgeline at 5 pm on
Tuesday, knowing that numerous cells of rain and thunderstorms were
moving eastward from New York. We hustled to get 22 nets up, then
quickly closed them as a wave of rain and strong hail hit us, with a few
lightning flashes much too close for comfort. We retreated to the
Octagon ski patrol hut and waited out the storms, a couple of us
returning once they passed to catch the dusk chorus and open a handful
of nets. The chorus was subdued at best, though 3 robins sang with
gusto.
The morning forecast promised clearing skies and
calm winds, so we were dismayed to climb out of our sleeping bags at
3:45 am and find the mountain still bathed in clouds, the vegetation
soaked. We made it back up to the ridgeline and dutifully reopened our
nets, only to have the skies open up at 4:30. Of course! Mercifully, by
the time dawn broke fully 20 minutes later and birds started to move,
the rain had subsided, and we were able to leave nets open. Over the
next 5+ hours, we watched our weather apps carefully, shook cloud
droplets from our nets, and hoped for the best. Bird activity was
predictably slow, but we managed to keep our nets open and capture a
total of 24 individuals, half of which were Bicknell's Thrushes (BITH).
This overall capture rate is well below 50% of what we'd normally expect
in late June, but birds simply don't move much when the coniferous
vegetation is soaked. Surprisingly, 5 of the 12 BITH were females with full incubation (or brood) patches. We'd have expected actively-nesting females to be sitting tight on their eggs or chicks. The only other female bird we captured was a robin, and she was in a net with a fledgling (which struggled out and escaped), so no longer attending her nest. Another surprise was capturing a female BITH that we had first banded as an adult of unknown sex in September 2011, next captured in September 2015 (still unknown sex, as they're no longer in breeding condition then), and not encountered again until yesterday. No doubt she nested locally but outside our netting area in each summer from 2011-16, and just happened to wander upslope this year, or is perhaps nesting closer to our nets.
Bicknell's Thrush 12 -- 5 new birds (3 males, 2 females) and 7 previously banded birds (6 from 2011-2016, 1 from earlier in 2017; 4 males and 3 females)
Swainson's Thrush (Olive-backed) 1 -- recapture of a bird banded as a yearling in 2016
American Robin 2 -- both new birds
Blackpoll Warbler 2 -- 2 returning males banded as yearlings in June 2016
Yellow-rumped Warbler (Myrtle) 3 -- 2 new yearling males; 1 male banded as a yearling in June 2015)
Dark-eyed Junco (Slate-colored) 2 -- 1 new, 1 banded on 22 June
White-throated Sparrow 3 -- males: 1 new, 2 returns (1 banded in May 2016, 1 in July 2014 and recaptured 2X in 2016)
View this checklist online at http://ebird.org/ebird/view/ch
Needless to say, we're hoping that our final 4 field trips in July present less challenging weather...
Chris
________________________
Chris Rimmer
Vermont Center for Ecostudies
PO Box 420 | Norwich, Vermont 05055
802.649.1431 x202
http://vtecostudies.org/
