1914] Bryant: Economic Status of tlic Western Mcadowlark 447 



Food op Nestlings 



Three methods are available for determining the food of 

 nestlings ; first, the rate of feeding may be determined by watch- 

 ing the number of trips made to the nest by the adult birds while 

 feeding the young; second, the young birds may be made to 

 disgorge their food; or third, the bird may be killed and the 

 food in the digestive tract examined. The first method has not 

 been used with any great degree of success because of the diffi- 

 culty in approaching near enough to the nest to observe the 

 feeding. The western meadowlark does not lieeome accustomed 

 to an intruder so easily as do other birds. The food observed 

 in the bills of adult birds carrying food to their young has most 

 often been cutworms or grasshoppers. One female bird, while 

 feeding, persistently flew into an oat field and returned each 

 time with cutworms. Another female bird was seen to catch 

 three or four grasshoppers in her bill, and then fly to the nest. 



Examination of the digestive tract of nestling birds has 

 sho\ra that they are fed very largely on cutworms, grasshoppers, 

 and ground-beetles. The stomaeks of two nestlings obtained from 

 the same nest contained egg-shells. This is not an unusual occur- 

 rence, for nestling birds of other species are fed on the egg-shells. 

 In no case was grain found in the stomachs, and in only a few 

 cases were weed seeds found. Young birds doubtless need a 

 larger quantity of food than adults. In almost every case the 

 stomachs were average full or over. This means that each stomach 

 contained nearly three cubic centimeters of food. Since it has 

 been shown that young birds need over one-half their own weight 

 of food each day, the birds when hatched must consume about 

 one-fourth of an ounce a day. and when ready to fly about two 

 ounces. 



This increased consumption of insects due to the demands 

 of young birds comes at a time when there are growing crops 

 which need protection and when insects are most numerous, thus 

 emphasizing the value of birds as balancers. The fact that 

 meadowlarks show a greater preference for certain kinds of food 

 while feeding the young enlarges their sphere of usefulness. 



In spite of the fact that a certain amount of grain and weed 

 seed is available, young nestling birds are fed almost entirely 



