226 BULLETIN 17 6, UNITED STATES NATIONAX. MUSEUM 



about twenty small grasshoppers, and many small, hard insects" in 

 its crop. 



Flies, plant lice, and mosquitoes frequently form an important 

 element of the food of the nighthawk. A nighthawk examined by 

 the Biological Survey had eaten more than 300 mosquitoes, and 

 E. H. Forbush (1907) reports finding 500 mosquitoes in the stomach 

 of one bird. McAtee (1926) reports that he found 650 plant lice in 

 the stomach of a single nighthawk. Phoebe Knappen (1934) found 

 stone flies in 21 nighthawks. The insects were chiefly adults but 

 also a few larvae, nymphs, and eggs were present. 



In the South various observers have noted that the nighthawk is 

 an important factor in the control of tlie cotton-boll weevil. F. H. 

 Herri ck (1901) writes of a nighthawk that had been feeding on 

 fireflies ; the wide open mouth of an adult observed feeding its young 

 was brilliantly illuminated like a spacious apartment all aglow 

 with electricity. F. H. Carpenter (1886) relates a unique experience 

 with nighthawks that darted at the artificial flies on his line when 

 he was casting for trout. It is not an unusual experience to see 

 nighthawks after dusk flying about electric lights of city streets 

 (Knowlton, 1896) or about campfires of remote districts where they 

 capture myriads of insects attracted by the lights. 



During the migration nighthawks frequently fly near the ground 

 and at such times may take advantage of any insects that appear in 

 their path. During an afternoon late in August I observed a flight 

 of several hundred nighthawks near Urbana, 111. As I sat in a car 

 alongside a large meadow I noticed that the birds were ravenously 

 feasting on grasshoppers. Some of the birds lingered long enough 

 to capture half a dozen of the insects before passing on to make 

 place for other nighthawks in the migrating procession. A. Dawes 

 DuBois, of Excelsior, Minn., relates a similar experience he had in 

 the vicinity of Salt Creek, Logan County, 111., as follows : "At dusk 

 on the evening of May 22, 1913, as I walked along a cloverfield, we 

 witnessed an assemblage of nighthawks in pursuit of low-flying 

 insects. They skimmed over the clover like swallows; and their 

 dusky forms were so numerous that they seemed to be weaving an 

 intricate pattern in the gray twilight. They were so intent on their 

 bountiful repast that they paid no heed to our presence, but some- 

 times darted past us only a few feet away." 



Nighthawks not only capture food on the wing, but they also have 

 been observed to drink, in the manner of swallows, as they skim near 

 the surface of the water of lakes and streams. F. Stephens (1913) 

 observed a nighthawk drinking from a watering trough. This bird 

 dropped its lower mandible into the water, rippling the surface of 

 the water as it passed along. A. Dawes DuBois writes of the follow- 



