FOOD HABITS. 2T 



FOOD HABITS OF BOBWIIITE. 



Both fidd and laboratory investigations of tlie food haijits of the 

 bobwhite have been conducted by the Biological Survey: The field 

 work was confined chiefly to Maryland and Virginia, arkd, although 

 it represents in some degree every month in the year, has been limited 

 mainly to the breeding and the hunting seasons. The laboratory 

 work to determine the difTerent kinds of food and their jaroportions 

 has included examination of the contents of crops and gizzards from 

 918 birds. This material was collected from 21 States, Canada, the 

 District of Columbia, and Mexico, but cliiefly from New York, Mary- 

 land, Virginia, Florida, Illinois, South Dakota, Nebraska, Kansas, 

 and Texas. Stomachs were obtained each month of the year, but un- 

 fortunately few were collected in the breeding season. Laboratory 

 work included also feeding experiments with three pairs of captive 

 bobwhites obtained from Kansas. 



The bird's digestive organs are well adapted to the character of its 

 diet. The stomach, or giz;zard, as it is commonly called, is provided 

 with powerful muscles for grinding the hard seeds on which the bird 

 largely subsists. The crop, a sac like enlargement of the oesophagus, 

 is a mere membranous receptacle for first receiA'ing the food, and is 

 without muscles. Its capacity is usually from four to six times that 

 of the stomach. 



The bobwhite is insectivorous as well as graminivorous. It is, in 

 fact, one of our most nearly omnivorous sioecies. In addition to 

 seeds, fruit, leaves, buds, tubers, and insects, it has been known to eat 

 spiders, myriapods, crustaceans, moUusks, and even batrachians. 

 The food for the year as a whole, calculated by volume and deter- 

 mined by analysis of the contents of 018 stomachs, consisted of vege- 

 table matter, 83. .59 per cent, and animal matter, lfi.41 per cent. In 

 addition, there was mineral matter varying in amount from '1 to 5 

 per cent of the gross contents of the stomachs, and in exceptional cases 

 rising to 30 per cent. This usually consisted of sand, with coarser 

 bits of quartz 2 to 7 mm. in diameter, which were taken to pulverize 

 the food and thus render it easier of assimilation. 



The vegetable part of the food consisted of grain, 17.38 per cent; 

 ■various seeds, chiefly weeds, 52.83 per cent; fruit, 9.57 per cent, and 

 miscellaneous vegetable matter, 3.81 per cent. The animal matter in 

 the food was distributed as follows: Beetles, 6.92 per cent; grass- 

 hoppers, 3.71 per cent; bugs, 2.77 per cent; caterpillars, 0.95 per 

 cent; miscellaneous insects, 0.70 per cent; and other invertebrates, 

 largely spiders, 1.36 per cent. 



The insect food of bobwhite, in comparison with that of other 

 birds, is interesting. It includes fewer caterpillars, ants, and other 

 Hymenoptera, but more bugs ; and, singularly enough in a terrestrial 



