MIGRATION . 
127 
All migrants are not desirable visitors. An 
inroad of hawks is far from pleasant for the 
birds of a neighborhood, or for other migrants. 
All through the month of September hawks 
abound. They circle round the peak of Cho- 
corua, seemingly for the pleasure of it. Often 
a dozen sharp-shinned and young Cooper’s 
hawks are in sight there at once. Sometimes 
great flocks of hawks pass across the sky, not 
circling, as the red-tailed and red-shouldered 
hawks are so fond of doing, but sailing straight 
before the wind like a fleet of mackerelmen 
running down the coast wing and wing. I once 
saw three hundred and thirty migrating hawks 
in one forenoon, most of them a thousand feet 
or less above the earth, but some so high that 
a powerful glass only just brought them into 
view. The stately progress of these birds, mov¬ 
ing many miles an hour without a wing-beat 
visible to the observer, is one of the wonders of 
nature. The Dead Tree is a resting-place for 
migrating hawks, eagles, and ospreys. I doubt 
not that by night it is used by owls, when they 
too move southward as their food grows scarce. 
In several different years I have seen my big 
blue heron sail away southward. In each in¬ 
stance it has been about four o’clock in the 
afternoon. Rising with slow and dignified 
flight, he makes two or three immense circles 
