Concord, Mass.
1901.
October 28.
  Brilliantly clear with light E. wind. A heavy white frost
covered the fields in the early morning but the middle of the
day was soft and warm.
  Both yesterday and today the woods between Ball's and
Davis's Hills have been alive with small birds chiefly
Chickadees, Golden-crests, Juncos & Tree Sparrows with a few
Yellow rumps and Brown Creepers. Yesterday I saw a
Canada Nuthatch and on both yesterday morning and this
I heard a Pine Linnet passing overhead.
  The Juncos and the Tree Sparrows have been feeding much of
late in the tops of the gray birches. At first I supposed 
they were eating the seeds of the birch cones with which
the trees were thickly hung but on watching them closely I
discovered that they were picking off the greenish Aphidae
which infest the leaves of the gray birches at this season.
The Yellow rumps, Chickadees and I think the Golden crests
also eat these Aphidae and on October 19th I saw a
number of Rusty Blackbirds feeding on them greedily.
  Early this morning as I was watching a flock of little
birds consisting chiefly of Chickadees, Kinglets, & Yellow-rumps
a brave Northern Shrike suddenly appeared in their midst.
His presence did not seem to cause the other birds any alarm
or even uneasiness nor did he show any inclination to attack
them, although more than once or more of them was
within a yard or two of him as he flitted from place
to place among the dense foliage of some white pines. He behaved
so nearly like a Blue Jay that at first I mistook him
for a bird of that species but I finally had a clear view
of him at short range.
Peculiar
behavior of a
Northern Shrike.
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