210 BULLETIN 146^ UNITED STATES NATIONAL MUSEUM 



other crustaceans, 21.12 per cent. The 2.28 per cent of vegetable mat- 

 ter is chiefly made up of weed seeds such as button weed, smart weed, 

 foxtail grass, and nightshade. He found that various kinds of wee- 

 vils were eaten such as those of alfalfa, cotton boll, clover, rice, white 

 pine, etc. In a single stomach he counted 41 alfalfa v/eevils. 



Harold C Bryant (1914a), during an outbreak of grasshoppers in 

 California, found that the contents of one stomach was 100 per cent 

 grasshoppers, and he estimated that each killdeer averaged 33 grass- 

 hoppers daily. Arthur H. Howell (1906) has found that the kill- 

 deer is among the most important of the birds that eat the cotton- 

 boll -weevil. Samuel Aughey (1878) found 258 locusts and 190 other 

 insects in the stomachs of nine birds taken in Nebraska. E. K. Kalm- 

 bach (1914) found in the stomach of a killdeer taken in a western 

 alfalfa field 316 weevils; in another 383. C. W. Nash (1909) has 

 found the stomachs of killdeers taken in orchards completely filled 

 with weevils, E. R. Kalmbach (1914) has also found May beetles 

 both in adult and grub form in the stomachs, wireworms, and insects 

 that attack sugar cane, corn, carrots, grape vine, sweet potato, to- 

 bacco, and sugar beets. Caterpillars, he found to be a favorite article 

 of diet, also grasshoppers and crickets, crane flies and their larvae. 

 One stomach contained hundreds of larvae of the salt marsh 

 mosquito. He adds: 



The killdeer thus befriends man, but it does something also for the domestie 

 animals, not only by eating horseflies and mosquitoes, as just mentioned, but 

 also by preying on ticks, including the American fever or cattle tick, which has 

 caused such enormous losses in some parts of the South. 



Arthur T. Wayne (1910) says: "This species is ver}'^ partial to 

 fields which are being ploughed, and at this time they are always very 

 tame, following each furrow as soon as it is turned over in order to 

 secure the worms which are exposed." I have watched a killdeer in 

 a ploughed field swallowing a large earthworm. Several strenuous 

 gulps were needed before the act was accomplished. 



Behavior. — The interesting behavior of this bird during courtship 

 and in the care of the eggs and young has already been detailed 

 under the approjjriate headings. In general it may be said that the 

 killdeer has the usual plover habits when feeding of alternately 

 running and then of standing still, as if to listen or look, always 

 with head up, and of dabbing suddenly at the ground for its food. 

 Like some other species of plover, it occasionally bobs or " teeters " 

 in a nervous manner. This varies from a slight bob of the head, 

 which is first hitched up and then brought down, to a bob combined 

 with a tilting up and down of the whole body on the hips. In swift 

 running they e«cel, and this serves them to good purpose in the 

 pursuit of insects. 



