BIRDS OF NEW YORK 73 



occasions I have found the nest of the Marsh hawk in small peat bogs 

 overgrown with huckleberries, cassandra and Labrador tea, the situation 

 being surrounded by cultivated fields and not far from the farm house. 

 The nest is nearly the size of a crow's nest, but not quite so deep, and 

 is composed entirely of grasses, twigs and weed stalks. The eggs, which are 

 laid from the 15th to the 30th of May, are from 3 to 7 or even 9 in 

 number, usually 5 or 6 in western New York, ovate in shape and bluish 

 white in color, often with obscure shell markings and brownish spots, and 

 nearly always much nest-stained. They average about 1.78 by 1.40 

 inches in dimensions. The period of incubation is 25 days or more, the 

 young hatching at successive intervals for several days, the female usually 

 beginning to sit as soon as 1 or 2 eggs have been laid, a habit which 

 has probably been acquired to protect the eggs from the attacks of crows 

 which would easily discover them, attracted by the light-colored eggs, as 

 they fly over the exposed nest. While crossing bogs like those in Bergen 

 swamp, Junius pond and Mendon pond I have several times picked up 

 eggs of the Marsh hawk which had recently been sucked by crows, and have 

 known them to treat the nests of Cooper and Red-tailed hawks in a similar 

 manner. Marsh hawk nestlings are covered with a buffy white down, 

 through which the wing feathers begin to show in about 10 days, and in 

 5 or 6 weeks they are able to fly. Nestlings which I brought up by hand 

 required each from 2 to 5 mice or English sparrows daily to supply the 

 cravings of hunger, so that the 5 young if left at Mendon pond would have 

 consumed 600 mice and small birds, more or less, before they left the nest. 

 The two old birds would consume in the 10 weeks of their sojourn near 

 the nest about 500 more. So it is easy to see that a family of Marsh hawks 

 on the farm makes a considerable difference in the abundance of meadow 

 mice, song sparrows and other small inhabitants of the fields. 



