Concord, Mass.
Ball's Hill.
1900
May 31.
  Cloudless with light W to S.W. winds. Oppressively
warm in the afternoon. Ther. 60 degrees - 83 degrees (78 degrees at 7.30 P.M.)
  My observations today showed very conclusively
that nearly all the northern bound migrants which were
here yesterday left during the night and that no fresh
arrivals came up from the South. Along the river front
of Ball's Hill I found the adult male Mourning warbler, 2 or 3
Water Thrushes, and 2 large Gray-cheeked Thrushes; behind
the Hill a Black-poll Warbler singing, the only one
met with during the day. The Canadian Warblers had
wholly departed and I could find no Wilson's Black caps.
North-bound
Migrants
Nearly all gone.
Mourning Warbler
Alice's Thrushes 
  In the Barrett woods, which I visited at about 
8 A.M., the only northern species noted were a Bay-
breasted and a Blackburnian Warbler which were 
in full song not far from Pulpit Rock. As the 
Blackburnian usually breeds in these woods the one
just mentioned was very likely settled for the Summer.
I not only heard but saw the Bay-breast, a fine
old male.
Bay breast Warbler 
  In a cluster of raspberry bushes near the barn at
the Barrett farm I found an Indigo Bird's nest with
2 eggs. The female came into a tree near by & chirped at 
me & the male sang a few times in the distance.
Indigo Bird's
nest at Farm.
  All our local birds were singing freely from 7 to 9 A.M.
and again towards evening. I heard 2 Brown Thrushes 
& 2 Field Sparrows in the morning.
  Previous to this afternoon I have heard only one
Bittern for two weeks or more. But from 4 P.M. to
sunset today there were two, one in the usual
place up river, the other nearly opposite the cabin.
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