Wyoming Birds. ii 



take thirty-one small locusts to their nest in an hour. A 

 pair of Rock Wrens took thirty-two locusts to their nest 

 in an equal period of time. 



INSTANCES OF EFFECTIVE WORK BY BIRDS. 



Many instances might be given to show that birds are 

 actually effective in checking outbreaks of insect pests. It 

 seems that birds are able to collect where insects appear in 

 unusual numbers, and so they put down uprisings which 

 threaten to do damage. It appears that. Prof. Forbes of 

 Illinois was the first to notice this ability of birds. 



1. Mr. O. E. Bremmer, in a letter to the Biological Sur- 

 vey, dated at San Francisco, March 16, 1908, says: 



"The canker worm episode is quite a common one with 

 us here. In one district * * * there has been a threat- 

 ened invasion of the prune trees several times, but each 

 time the Brewer's Blackbirds can^e to the rescue and com- 

 pletely cleaned them out. I have often seen bands of black- 

 birds working in an infested orchard. They work from 

 tree to tree, taking them clean as they go. If a worm tries 

 to escape by webbing down, they will dive and catch him in 

 mid air." 



2. There is a true story which reads like a myth, since 

 it tells how the pioneers of Utah were saved from starva- 

 tion by the timely appearance of a flock of gulls. In the 

 spring of 1848, the Mormons had planted several hundred 

 acres of wheat in the valleys southeast of the present site 

 of Salt Lake City. In May the fields were green and beau- 

 tiful, but in the latter part of this month a horde of Rocky 

 Mountain Crickets came down from the hills and devoured 

 every green thing in their path. The fields were black with 

 these clumsy insects and the" people were desperate. After 

 trying in vain to destroy them by various means, they were 

 almost disheartened, when a flock of Sea Gulls came from 



