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I joined our field crew on East Mt. Tuesday night and 
Wed.  Bicknell's Thrush (BITH) continue to be very active there, 
singing and calling.  We mist-netted 4 previously unbanded 
males.  This has been a "banner" summer for BITH, following 2 
productive breeding seasons, when numbers of red squirrels were low 
(they are a major predator).  Squirrel populations track fir cone 
crops, which generally follow a two-year boom or bust cycle in 
montane forests.  The pattern occasionally skips a year, and 
2005-2006 both featured low squirrel numbers, with the result that 
BITH (and other open-cup nesting species) enjoyed relatively high 
breeding productivity.  BITH numbers have generally rebounded 
throughout the Northeast in 2007, with mountains like Burke -- a 
small peak on which we have detected no more than one BITH since the 
late 1990s, none last year -- supporting good numbers.  I found 3 
BITH on Burke in early June.  I managed to mist-net all 3, and 2 were 
yearlings.  A high proportion of the BITH we've captured on East, 
Mansfield and Stratton are also yearlings, reflecting 2006's solid 
productivity.

This summer features a different story in terms of squirrel 
populations.  Many of you will recall last fall's massive cone 
crop.  The mountains are now overrun with squirrels!  East Mt. in 
particular has obscene numbers, like nothing we have ever seen.  They 
are undoubtedly depredating nests of BITH and other species, which 
means that many birds will renest after failing, accounting at least 
in part for the continued strong vocal activity, at a time of summer 
when things normally begin to quiet down.  The good news is that the 
2007 cone crop is all but absent, so BITH should have a relatively 
squirrel-free 2008.

Pine Siskins and White-winged Crossbills continue to be present on 
East in small flocks.  We caught a family of recently-fledged Boreal 
Chickadees and a female Black-backed Woodpecker that we had banded in 
2005.  Blackpoll Warbler numbers continue to be low.

I spent the late mornnig and afternoon atlassing along the access 
road to East Mt, which like the summit is on the Seneca Mt. 6 
block.  Interestingly, Blackpolls were all over the place in suitable 
habitats of dense, small fir and spruce, at elevations of 6-800 m.  I 
flushed a female off a nest with 2 eggs and had at least 6-7 pairs 
carrying food.  I wish other species had been as easy to confirm.... 
I needed 11 new confirmations but only came away with 6.  All were of 
adults carrying food and/or feeding fledglings, and included 
Black-throated Green Warbler, Black-and-white Warbler, Canada 
Warbler, Mourning Warbler, Common Yellowthroat, and Lincoln's 
Sparrow.  Two interesting new species for the block included a female 
Tennessee Warbler and a (Western) Palm Warbler at the edge of a small 
bog -- both investigated my pishing, but neither had food or acted 
agitated as if a nest or young were nearby.

Chris
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Chris Rimmer
Conservation Biology Dept.
Vermont Institute of Natural Science
6565 Woodstock Road
P.O. Box 1281
Quechee, VT 05059
802-359-5001 ext. 230
www.vinsweb.org/cbd/index.html