Despite challenging weather, with low clouds and a very slowly clearing 
NW wind soaking the vegetation, the VCE field team was able to run mist 
nets on our Mansfield ridgeline study plot on Thursday morning.  No big 
surprises, but Bicknell's Thrushes were even more vocally active than 
during our previous visit 2 weeks earlier.  A loose group of 10 Turkey 
Vultures over the ridgeline in late morning, after clouds had lifted, 
was an unprecedented number up there.

A number of observers around the Northeast have remarked on the apparent 
influx of Swainson's Thrushes (SWTH) on mountaintops this June, in some 
cases seeming to "replace" many of the Bicknell's Thrushes (BITH) that 
would have formerly been present.  VCE has certainly detected an 
increase of SWTH on Mansfield in the last few years, especially in 2011 
and this season.  The species used to be uncommon on the ridgeline, but 
now rivals BITH in abundance - we've captured 15 so far, and only one is 
a bird banded in a previous year.  We haven't yet looked closely at our 
mist net or point count data, but BITH appear to be at about "normal" 
numbers - we've so far caught 18 individuals, including 6 females with 
full incubation/brood patches.  There are also greater numbers of 
American Robins, Magnolia Warblers, and Yellow-bellied Flycatchers on 
the ridgline this season, the latter two species typically being found 
more commonly on forested slopes below the ridgeline.  It would be 
interesting to know whether others are documenting, or even sensing, 
similar changes on mountaintops in Vermont or elsewhere.


Mt. Mansfield - MANS, Lamoille, US-VT
Jun 28, 2012 4:30 AM - 11:30 AM
16 species

Turkey Vulture  10
Yellow-bellied Flycatcher  2     calling
Common Raven  1
Red-breasted Nuthatch  1
Winter Wren  4     singing
Bicknell's Thrush  16     singing and calling
Swainson's Thrush  8     singing and calling, fewer than previous June visits
American Robin  10
Magnolia Warbler  2     singing
Blackpoll Warbler  8     singing
Yellow-rumped Warbler  8
White-throated Sparrow  12
Dark-eyed Junco  6
Purple Finch  2     pair
White-winged Crossbill  2
Pine Siskin  3

This report was generated automatically by eBird v3 (

Chris Rimmer
Vermont Center for Ecostudies
P.O. Box 420
Norwich, VT 05055
802-649-1431 ext. 1