PELICANS, CORMORANTS, AND PETRELS. 257 
Susquehanna, but is reported now by Dr. Warren to 
occur in Pennsylvania only on the lake-shore in Erie 
County. Dr. Turnbull says they are “ rare;” many, 
however, pass along the coast to winter farther south. 
As the cormorant feeds almost exclusively on fish, 
if not quite so, it is necessarily an expert swimmer 
and diver. It can remain a long time, too, under 
water. “ The activity the bird displays under water 
is almost incredible to those who have not seen its 
performances, and in a shallow river scarcely a fish 
escapes its keen eyes and sudden turns, except by 
taking refuge under a stone or root, or in the mud 
that may be stirred up during the operation, and so 
avoiding observation.” 
This bird builds a conical nest of sticks with a de- 
pression at the top. In some localities this and the 
preceding are found nesting in the same place. They 
choose cliff-sides, surfaces of rocky islands, and some- 
times trees. They are soon fouled by the excre- 
ment of the birds, and with the ground immediately 
surrounding “ generally look as though bespattered 
with whitewash.” 
Moseley, in “ Naturalist on the ‘ Challenger,’” gives 
the following amusing anecdote of a species of cormo- 
rant he saw in the South Pacific at Kerguelen Land. 
“An idea of the relations of the various birds to one another in 
the struggle for existence will be gained from the following incident : 
I saw a cormorant rise to the surface of the water, and lifting its 
head, make desperate efforts to gorge a small fish which it had caught, 
evidently knowing its danger, and in a fearful hurry to get it down. 
Before it could swallow its prey, down came a gull, snatched the fish 
after a light struggle, and carried it off to the rocks on the shore. 
Here a lot of other gulls immediately began to assert their right to a 
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