Concord, Mass.
1908.
April 27
  Clear and warm with light S.E. wind.
  I noted today for the first time this season
Least Flycatcher 1 singing in our orchard at 6 A.M. & later
Bank Swallow - heard near Bensen's at 5 P.M.
Cat bird - One seen by Gilbert by roadside, Punkatasset Hill
Arrivals
  This is the fourth day that the Chickadees have been
at work excavating their nest in the apple tree by our
dining room window. They begin soon after sunrise and
labor ceaselessly through the forenoon but, as far as we have
observed, they never work at all in the afternoon although
they sometimes come to the hole as if to see that all is
right there. They are boring nearly straight down & have
already got to a depth of about five inches. The work is
shared equally one bird succeeding the other the instant
the first has taken wing with a mouthful of chips.
Each bird usually makes a visit to the hole about once every ten
seconds, so rapidly do they work.
Chickadees building
  There is a round hole about 3.5 inches in diameter sixty
feet above the ground in our big elm in which a pair
of Flickers bored their nest six or seven years ago. It has
since been occupied at all seasons by Gray Squirrels. I have
seen these animals enter & leave it within a week. Yet this
morning about 8 o'clock one pair of White-bellied Nuthatches
were building a nest there. The female did most of the work
& performed it with remarkable rapidity. She would run 
out on a large branch pry off a scab of bark 5 or 6 inches long
take it into the hole & almost instantly reappear and go after
another. The male occasionally got one and poked it into
the hole without entering himself.
Nuthatches building in Squirrel hole high up