NORTHERN CLIFF SWALLOW 477 



Lepidoptera were not important; very few birds are fond of 

 adult butterflies or moths though they may relish their lai-vae. 

 Orthoptera, according to Beal, are lightly regarded by the cliff swal- 

 low, but Bryant (1914) includes the cliff swallows as destroyers of 

 grasshoppers in California. He reports that an individual cliff 

 swallow eats on the average of three grasshoppers a day. Beal 

 found a few other insects, such as dragonflies. Mayflies, and lace- 

 winged flies, represented in the food. McAtee reports that 18 speci- 

 mens of the southern corn rootwonn {Diahrotica duodecimpunctata) 

 in the stomach of a single cliff swallow. Murie (1935) examined a 

 cliff swallow killed by an automobile; it had its crop filled with 

 brine flies {Ephydra millbrae). The cliff swallow is one of the birds 

 responsible for the destruction of mosquitoes. 



It is evident from the above determinations that the cliff swallow 

 is distinctly beneficial to the best interests of man as far as its food 

 habits are concerned. It is also obvious from the nature of the in- 

 sects eaten that the cliff swallows capture the greater part of their 

 food during flight, 



Beal (1907) in a special investigation conducted in California 

 identified the food of 22 nestlings varying in age from two days to 

 those just leaving the nest. They were taken from May 30 to July 

 2, inclusive. Beal found animal matter in the food of the young 

 to be similar to that eaten by the adults but differing in its relative 

 proportions. Soft-bodied insects, such as Hymenoptera and Diptera, 

 ranked highest, amounting to three-fourths of the food eaten by the 

 young. Hemiptera and Coleoptera, hard-bodied insects, which are 

 freely eaten by the adults, represented a relatively small percentage 

 of the food of the young. An unaccountable difference existed in 

 the fact that a considerable amount of gravel was taken from the 

 stomachs of the young, while none was found in the stomachs of the 

 adult cliff swallows examined. 



Brown (1910) made observations of the feeding activities at col- 

 onies of cliff swallows in Washington County, Maine. He counted 

 the number of visits of the adults and, finding that they carried on 

 an average of three insects each trip, estimated that 900 insects 

 were destroyed on an average for each day the young were in the 

 nests. Such figures should convey a distinct meaning to those who 

 may be ignorant of or doubt the value of the cliff swallow in its 

 relations to the farmer on whose buildings it seeks a nesting site. 



Voice. — The swallows are not distinguished as far as their songs 

 are concerned, and in this the cliff swallow is no exception. Roberts 

 (1932) states: "The notes consist of a rapid twittering or chattering, 

 sometimes rather harsh and creaky, but during the nesting-season 

 these acquire a more musical quality and fill the place of a more 



