12 



THE oOlogist liTCO 



The JJse of Old Nests. 



It is a strange economy of Nature, 

 which impels Hawks and Owls, to use 

 old and unattractive nests, when but 

 little energy need be expended, in the 

 construction of new abodes, when each 

 would then build, and differentiate, 

 according to his specific instinct. 



April 18th. 1695, we saw an Accipiter 

 cooperi nearby a nest which was just 

 begun, and concluded that she was 

 constructing same. May 5th, the nest 

 was completed, and on May 19th, we 

 took therefrom a set of five slightly in- 

 cubated eggs. The nest was typical of 

 the species, very bulky, composed of 

 small sticks and lined with the outer 

 bark of chestnut in chunks from two 

 to five inches long, and from one-half 

 to one and one-half inches wide. It 

 was placed in the crotch of a tall, slen- 

 der chestnut tree, fifty-five feet from 

 the ground. In 1896 this nest was occu- 

 pied by a Barred Owl, which hatched 

 its clutch there. When we visited the 

 site April 13th, the shells, strewn about 

 the base of the tree, appeared as if the 

 young had been hatched a day or two 

 previously. The nest appeared, from 

 the ground, as if some inner bark and 

 leaves had been added since it was oc- 

 cupied by the Cooper's, but I think 

 this was probably done by squirrels, 

 during the preceding Fall, as I have 

 never known the Barred Owl to do 

 anything toward building a nest, or 

 fixing over an old one. They appear 

 to be satisfied with what they can find. 

 We again visited this site, in the Fall of 

 '96 and saw by the numerous tracks 

 about the tree, that the nest was occu- 

 pied, but, by what we could not 

 make out, as the tracks were strange to 

 us. A charge of shot into the nest 

 brought down a pair of old, and four 

 young, white-footed mice. This ended 

 the history of that nest, as it was blown 

 down the following winter. 



April 21, 1896, and April 11th, 1897, 



we collected sets of four Red-should- 

 ered Hawk's eggs from a nest in the 

 crotch of an oak tree, forty-one feet 

 nine inches from the ground. The nest 

 was a typical Buteo's, made of large 

 sticks and containing much inner bark. 

 In '98 the Red shouldered Hawk did 

 not appear but a pair of Cooper's added 

 to the top a few small branches, and 

 reared their young there. During the 

 winter of 1898-1899 this nest was blown 

 down Last spring the Cooper's Hawks 

 built a new nest, whose history we 

 spoiled by removing it entire, together 

 with its complement of three incubated 

 eggs, to our den. 



In 18S7, on April 20th, we located 

 nests of the Red-shouldered and Coop- 

 er's Hawks, which were not more than 

 two hundred feet distant from each 

 other. These were both of the build of 

 '97 and were typical, each, of its spec- 

 ies. The Red-shouldered's nest con- 

 tained two slightly incubated eggs, 

 which we took. The nest of the Coop, 

 er's was just completed. On April 

 30th, we took a set of four fresh eggs 

 from it. Visiting the locality after 

 Chickadee's eggs on May 12th, the 

 same year, we were surprised to start a 

 Cooper's Hawk from the Buteo's nest. 

 A climb to the nest showed that every 

 vestige of the inner bark had been re- 

 moved. A few small sticks had been 

 added, and the nest relined with outer 

 bark. The nest contained three eggs 

 of the Cooper's. One of the eggs look- 

 ed as if it might have been deposited 

 many days before the other two, as it 

 had lost all its bluish tint, and other- 

 wise appeared to be highly incubated, 

 while the remaining two had the ap- 

 pearance of being perfectly fresh. We 

 believed, and still do, that this faded 

 egg was part of the first set, which had 

 been taken before it was completed, 

 so we decided to take the set to see if 

 this would not be evidenced by the dif- 

 ferent stages of incubation. But, on 

 blowing, it proved no different from 



