Lancaster, Mass.
1902.
June 3
  Clear and hot with short but sharp thunder shower
at 3 P.M.
  Started off with John E. Thayer & his assistant Harriman
at 9 A.M. He drove directly to the fine old forests of
white pines beyond the Pansy Farm on the road to Harvard.
Tying the horse in the usual place we spent the entire
forenoon looking for nests of the Blackburnian Warbler but
without success. The birds were even more numerous than 
last year. I counted eleven different males singing within
a space of less than fifteen acres and at one time heard four
within twenty yards of one another. I do not think that I
have ever found a greater number in an area of similar
extent even in the most favored locations at Umbagog.
No females were seen. The males kept in the tops of the 
largest or, at least, tallest pines and sang almost continuously
through the entire forenoon. The song of the Blackburnian
has two regular variations which I noted to-day as follows:-
We-we-we-we-we -e-e-e-e (running up the scale towards the end like
an Usnea Warbler's song) and we-chee, we-chee, we-chee, we-chee,
we-chee very like that of Mniotilta varia. The same individual
bird often uses both forms, repeating one a dozen times or
more in succession and then changing to the other, All the
notes of both songs have a peculiar metallic quality by which
the voice of their author may be at once distinguished from
that on any other of our Warblers although in form his
song resembles that of the Usnea Warbler or of the Black & White Creeper
very easily at times, as I have just indicated. Or, to put
the matter in another way, his song, whatever may be its form,
never possesses the guttural quality of the Usnea Warbler's
nor the fine wiry character of the black & White Creeper's.
Visit to a breeding haunt of the Blackburnian Warbler
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