Subject: Re: Lincoln's Sparrow
Date: Oct 24 21:37 PD 1996
From: Michael Price - mprice at mindlink.bc.ca


Hi Tweets,

Re: Lincoln's Sparrows

Michael Smith writes:
(snip)
>They look only superficially like a Song Sparrow, that is, same
>genus, and same general gray-and-brown patterns. But the Lincoln's is
>smaller, and has a very distinct buffy breast. And Lincoln's Sparrow is
>noted for raising its crest when alarmed. They're pretty easy to
>differentiate.

Lincoln's Sparrow (LISP) seems to have a buffy breast mostly in
post-Alternate plumage, so you're more likely to see it on LISP's in the
southbound migration or on the few overwintering birds: on the northbound
birds I've seen in Vancouver BC and on the breeding grounds in north-central
BC, I was surprised to see that the adults usually had a pale grey breast
finely streaked medium grey with little to no buff wash, with little buff
even in the malar stripe, and the average territorial adult of either sex
had a small coalescent central breast spot on the streaked breast as the
most conspicuous plumage feature. They then can be *quite* similar to Song
Sparrow (SOSP) at first glance. Pyle's Passerine Guide has virtually nothing
on LISP, though, to help with real fine points (unusual for such an abundant
and abundantly-caught species). One's unlikely, though, when up north to see
a territorial SOSP singing from atop a 5-meter shrub or tree isolated in the
middle of a new clearcut, where LISP is going to be, with Dark-eyed Juncos,
the common breeding species.

On territory, they were more likely to use a 'tchap' call note, like a junco
alarm-note (also used by Savannah and Fox Sparrows) but off-territory,
whether in migration or on wintering territory, you're much more likely to
locate them by their soft, junco-like 'bzzt' calls. Their territorial songs
are closest in phrasing, pitch, and quality to that of the House Wren
(HOWR), except slightly drier. It's a clear loud bubbling trill, dropping at
the end, so similar that in the case of one territorial male in one of our
study areas, the song was actually identical (I grew up in southern Ontario
where HOWR are a common backyard resident). Only the knowledge that the
nearest House Wren was likely over a thousand kilometers to the south plus a
visual confirmation convinced the 'but-maybe' part of me that it was a LISP
male.

I've found that a good way to hike 'em up into view is to use a modified
form of pishing, where a sustained, high-pitched sibilant 'pssssst,
psssssssssst' seems to engage their curiosity quicker than the conventional
technique. If you sustain this sound for several minutes, more and more LISP
will jump up, crests raised, until as many as ten or fifteen may be visible
in a scrubby little patch you'd think couldn't support one (of course, if
you sustain this sound for several minutes, you're likely to hyperventilate
and pitch forward into the marsh face-first, if some exasperated birder
doesn't help you on the way with a well-placed foot first). When they hop up
from the grass into a shrub for a better look, they almost invariably go the
lowest branch first, then ascend branch by branch until their curiosity is
satisfied. If in reeds, they similarly start low and slowly work upward.

Average arrival and departure dates in Vancouver BC are northbound arrival
Apr 07, northbound departure May 03; average southbound arrival is Aug 25,
departure undeterminable by present record-keeping. Apparently small numbers
(10-30, probably higher) overwinter in rough pasture and saltmarshes
throughout the checklist area.



Michael Price If asked "What is Man?" a biologist might
Vancouver BC Canada answer, "Well, 99% a Chimpanzee..."
mprice at mindlink.net -The Economist