108 BULLETIN 17 0, UNITED STATES NATIONAL MUSEUM 



fluttered wings and definite approach towards the male. The male 

 was observed to call only when actually dropping down to the female." 



According to my observation, coitus, which often takes place on the 

 branch of a tree, is a noisy, boisterous proceeding, accompanied by a 

 good deal of wing flapping on the part of the male bird. 



Nesting. — Unlike most hawks, which either make true nests in trees 

 or lay their eggs on open ledges of bare cliffs, the sparrow hawk, in the 

 great majority of instances, hides its eggs away in deep hollows — 

 either in a natural cavity in a tree or in a hole excavated by a flicker 

 or some woodpecker of similar size. 



W. E. D. Scott (1886) speaks of the bird in an arid part of Arizona 

 as breeding "commonly in deserted Woodpecker holes in the giant 

 cacti wherever they flourish", and, in a letter to Mr. Bent, A. Dawes 

 DuBois reports a remarkably high nest "in a hole in a dead branch at 

 the top of a tree, at a measured height of eighty-one feet above the 

 ground." R. C. Harlow (1912) mentions a nest site in "an enormous 

 natural cavity, two feet in diameter", and Bendire (1892) reports an 

 unusual case of its resorting "to holes in sandstone cliffs and clay 

 banks." 



Dr. Louis B. Bishop writes to Mr. Bent of a nest in a hole in an elm 

 tree, 20 feet up, in which a female sparrow hawk was "sitting on one 

 golden-eye's egg, with the others and her own eggs around her. The 

 hole was reported to have been used by the golden-eye in previous 

 years." 



On rare occasions the sparrow hawk uses an open nest of another 

 bird — a habit it shares with the pigeon hawk. Thus Dice (1918) says: 

 "A nest was found * * * [in southeastern Washington] in an 

 old magpie nest about twelve feet high in an osage hedge", and Rock- 

 well (1909), speaking of sparrow hawks breeding in magpies' nests, 

 says: "The Sparrow Hawk, unlike the preceding species [screech 

 owl], seems to prefer nests which are rooft over, and instances where 

 the eggs are deposited in open nests are quite rare. It is of some 

 interest to note that Sparrow Hawks nesting in this manner are much 

 more timid than those nesting in cavities, and whereas it is a common 

 occurrence to find a brooding female so fearless that it is necessary to 

 remove her from her eggs in a cavity, it is seldom that one can ap- 

 proach within thirty yards of a bird brooding in a magpie's nest with- 

 out flushing it. Apparently the bird does not feel perfectly secure in 

 a location which is not altogether natural to the inherited instinct of 

 the species." 



Since the advent of civilized man to the country, the sparrow hawk 

 frequently makes use of buildings and bird boxes for breeding purposes. 

 The birds habitually use their chosen cavity as they find it. They 

 add little if any nesting material but lay their eggs either on the bare 

 floor or on whatever the previous occupant has left behind. Illus- 



