7,6 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 85 



and beetles, though we have none of these forms in the United States ; 

 the mole crickets and a few other forms have special fetid secretions, 

 and the brown drop that so many orthoptera exude from the mouth 

 when captured is said to be a protective device. 



Bird enemies. — Nearly a tenth of all the identifications of insects 

 in bird stomachs are of leaping orthoptera. To name the birds that 

 eat grasshoppers is to name all birds not strict vegetarians. When 

 these insects are abundant, birds of all sizes turn their attention to 

 the Orthoptera and for the time being make them a staple food. As a 

 constant article of diet also, they are important to many birds. The 

 number of identifications of Saltatoria from stomach contents was 

 50 or more in the case of over 20 species of birds, more than 100 in 

 22 additional species, more than 200 in 10 other species, in excess of 

 1,000 in two cases, namely, of the common crow, and the meadowlark, 

 and more than 1,500 for the starling and crow blackljird. Expressed 

 in proportions of the annual subsistence of certain birds most fond 

 of the insects, we find according to Biological Survey records that 

 Saltatoria compose 21.29 per cent of the food of the western bluebird 

 (based on the examination of 217 stomachs), 22.01 per cent for the 

 eastern bluebird (855) ; grasshopper sparrow (170), 23 per cent; the 

 eastern and western meadowlarks combined (1,514), 26.08 per cent; 

 the Arkansas kingbird (109), 27.76 per cent; Franklin's gull (93), 

 43.43 per cent ; and the scissor-tailed flycatcher (129), 46.07 per cent. 



These are illustrations of the relations of birds to leaping orthoptera 

 under normal conditions. When species of these insects become exces- 

 sively abundant as they frequently do, the gathering of the bird clans 

 to feed upon them is proverbial. No instance is more celebrated than 

 that studied by Prof. Samuel Aughey during an invasion of the Rocky 

 Mountain locust in Nebraska. He found locusts in the stomachs of 

 no fewer than 172 species of birds varying in size from tlie tiny 

 hummingbirds up to the largest hawks, and including such usually 

 exclusively vegetarian birds as the passenger pigeon and mourning 

 dove. Professor Aughey was eye-witness also to 33 additional species 

 of birds preying upon the locusts.* 



For a modern illustration of the same phenomenon, we may cite a 

 brief investigation made by the Biological Survey during a grasshopper 

 outbreak in South Dakota in 1920. Out of the 26 species of birds 

 collected, representatives of 24 had been eating the hoppers ; of 19 

 species every bird collected had taken grasshoppers, and for the 



' Notes on the nature of the food of the birds of Nebraska. First Ann. Rep. 

 U. S. Ent. Comm. (1877), App. II. pp. [i3]-[62L 1878. 



