1903.
June 19
(No 2)
and congenial a nesting place? As I was speculating
 on this point I noticed some scratches on the face of
the bank immediately below one of the holes. On examining
the other holes I found that only one (that which I had
seen the birds enter) was without those tell-tale marks.
Invariably they extended from the bottom of the hole (ie of
its entrance) nearly or quite to the foot of the vertical part
of the bank and in some instances they were also present
on one or both sides of the hole. They resembled deep
pin-scratches running nearly straight up and down. Usually
there were five of them, from 1/8 to 1/4 of an inch apart and
perfectly parallel even where they followed a somewhat
wavy course but in places on two or three could be
distinctly traced. Most of them looked rather fresh but
some had become much obscured by the action of
the weather. Quite evidently they had been made by
some animal with sharp-pointed claws in climbing to,
descending from, or clinging just below, the holes.
At first I suspected the creature to have been a cat
for I remembered to have seen a large black cat perched
on a narrow shelf at the sand bank at Concord last 
summer striking at the anxious and excited Bank Swallows
as they darted in swarms close about her. A little
reflection convinced, me however, that no cat would be
likely to so utterly break up so large a breeding colony
as this. I therefore descended to the river bank hoping
to find the solution of the mystery there. Nor was
I disappointed for the entire expanse of smooth, wet
sand along the water's edge was thickly covered with
Mink tracks. They were of various ages from perfectly
fresh-looking imprints that clearly showed the marks