18 GAME, AQUATIC, AND KAPACIOUS BIRDS. 



New Jersey has spent thousands of dollars in trying to reduce the 

 numbers of this pest. The killdeer thus befriends man, but it does 

 something also for the domestic animals, not only by eating horseflies 

 and mosquitoes, as just mentioned, but also by preying upon ticks, 

 including the American fever or cattle tick, which has caused such 

 enormous losses in some parts of the South. 



Crawfish, well-known pests in levees, and even in corn, cotton, and 

 other fields in certain localities, are another item of the killdeer's 

 food, and 3,62 per cent of the subsistence of the 228 birds examined 

 was composed of worms of the genus Nereis, which prey upon oysters. 



In all, 97.72 per cent of the killdeer's food is composed of insects 

 and other animal matter. The bird preys upon many of the worst 

 crop pests and is a valuable economic factor. There can be no 

 logical reason for continuing to regard it as a game bird. w. L. M. 



HORNED GREBE. 



( Colymbus auritus.) 



Grebes are among the most interesting of water birds. Their 

 power of diving as quick as a flash or of sinking beneath the surface 

 without leaving a ripple has earned for them such names as hell-diver, 

 sprite, and water witch. Grebes are not only accomplished divers, 

 but swim well under water for long distances not exclusively by 

 aid of the feet, however, as is often stated. The writer has more 

 than once seen the pied-bill grebe using its wings in underwater 

 progression. Grebes have difficulty in rising from the water, but fly 

 well when under way. When alighting they strike the water with a 

 splash, gliding some distance on the breast. The nests are built of 

 water-soaked vegetation, a portion of which is used to cover the eggs 

 in the absence of the parents. 



To illustrate the food habits of grebes, the horned grebe (fig. 7) is 

 chosen. This species has a circumpolar range. In North America 

 it breeds from the northern tier of the United States northward, and 

 winters from the southern boundary of the breeding range south to 

 Florida and California. The most remarkable point about the food 

 habits of grebes is that the stomachs almost invariably contain a 

 considerable mass of feathers. Feathers are fed to the young, and 

 there is no question that they play some essential though unknown 

 part in the digestive economy. As they are finely ground in the 

 gizzards it is probable that finally they are digested and the available 

 nutriment assimilated. Feathers constituted practically 66 per cent 

 of the contents of the 57 horned grebe stomachs examined. How- 

 ever, it is not likely that they furnish a very large percentage of the 

 nourishment needed by the birds. As the nutritive value of the 

 feathers is unknown, this part of the stomach contents is ignored. 



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