SHARP-SHINNED HAWK 97 



year. The height from the ground, of my other 17 nests, varied 

 from 20 to 55 feet, and about half of them were between 30 and 35 

 feet. The nests were all made of small sticks or twigs, and about 

 half of them had no lining at all, except a smooth layer of finer 

 twigs in the hollow of the nest; in others a few chips of outer 

 bark of the pine had been added. Most of the nests were freshly 

 built, but some of them were evidently old nests, to which new mate- 

 rial had been added. The presence of many old nests, in a grove 

 occupied by these hawks, indicates that they prefer to build a new 

 nest each year. This hawk often builds a very large nest in propor- 

 tion to its size, so that the incubating bird is invisible from below; 

 but often, on the smaller nests, the bird's tail may be seen projecting 

 over the edge. A typical large nest, w^hich was in use for its second 

 consecutive year, had outside measurements of 26 by 25 inches; it 

 completely encircled the trunk of the tree and from the trunk to the 

 outer edge it was 16 inches wdde; it was 7 inches in height; it 

 measured 6 inches across the inner cavity, which was 3 inches deep, 

 very deeply hollowed for this species. There is much individual 

 variation in the behavior of different birds ; sometimes the incubating 

 bird will sneak quietly off the nest, as the intruder approaches, and 

 not show herself again; in such cases it is easy to pass by a nest 

 and not notice it; another may not leave the nest imtil the tree is 

 rapped; still another may stick to the nest until the climber is part 

 way up the tree; and once I saw the climber within 3 feet of the 

 nest before the sitting hawk left. Even if the hawks are not seen 

 or heard, there are other signs to guide the collector to the nest. 

 During the courtship season in April, the shrill plaintive call notes 

 of the male may be heard in some likely spot, and the chances are 

 that a nest will be built near there later. After incubation begins 

 one may see a small bit of white down on or near an occupied nest ; 

 but there is never so much down to be seen on an Accipiter's nest 

 as is usually seen on a Buteo's, and oftener there is none. But almost 

 always a patch of woods occupied b}'^ a breeding pair of sharpshins 

 shows ample signs of their bird-killing habits, wings and feathers 

 of domestic pigeons, robins, blue jays, and other small birds; often 

 cast-off flight feathers of the hawks are seen, as they begin to molt 

 in May. Where such signs are abundant it pays to climb to every 

 likely looking nest. A sharp-shinned hawk's nest is usually recog- 

 nizable as a broad, rather flat platform of clean sticks, built on hori- 

 zontal branches against the trunk, quite unlike a crow's nest. 



I have seen a pair of these hawks acting as if they had a nest 

 in a dense cedar swamp, but I have never found a nest in such a 

 situation. Others have found them in other parts of New England 

 nesting in cedars, hemlocks, spruces, and firs, but very seldom in a 

 deciduous tree. Out of eight Massachusetts nests recorded in Col. 



