SUPPRESSION OF PESTS BY BIRDS — McATEE. 419 



States, many years ago, and which was then expected to render the 

 profitable growing of potatoes impossible — the Colorado potato 

 beetle — is now known to be eaten by a large number of birds. One 

 of these, the rose-breasted grosbeak (Zamelodta ludoviciana) has 

 been reported to clear fields of the beetles in various localities 

 in Pennsylvania, Wisconsin, and Iowa. A striking instance was re- 

 corded by Prof. F. E. L. Beal, before his death a member of the 

 United States Biological Survey, who describes 14 

 a small potato field [in Iowa] which earlier in the season had been so 

 badly infested with the beetles that the vines were completely riddled. The 

 grosbeaks visited the field every day, and finally brought their fledged young. 

 The young birds stood in a row on the topmost rail of the fence and were fed 

 with the beetles which their parents gathered. When a careful inspection was 

 made a few days later, not a beetle, old or young, could be found; the birds 

 had swept them from the field and saved the potatoes. 



According to Vernon Bailey, of the Biological Survey, the cliff 

 swallow {Petrochelidon lunifrons) must also be credited with the 

 local suppression of the potato beetle. He states that — 



In 1891 Mr. Denney Smith, who then lived on a farm about a mile from my 

 father's farm at Elk River [Minn.] found that his potatoes were covered with 

 young and old potato bugs. He bought 10 pounds of Paris green, but did not get 

 ready to apply it for several days, and when he went into the field again he found 

 that the potato bugs had nearly all disappeared and that a large colony of cliff 

 swallows, which had built under the eaves of his barn, were constantly skimming 

 up and down between the rows of potato vines. Mr. Smith could account for the 

 sudden and unusual disappearance of the potato bugs only on the supposition that 

 the swallows had picked them off the vines, which he thought he could see them 

 doing. The Paris green was never applied and a good crop of potatoes was 

 harvested. 



Asparagus is subject to severe attack by beetles of the same family 

 as the potato beetle. Constant aggressive measures against these pests 

 are usually necessary in order to get a crop, but occasionally birds 

 prevent this necessity. Such a case is given by M. F. Adams, of 

 Buffalo, N. Y., who says: 15 



Beetles and larva? of [asparagus beetles] Crioceris asparagi and C. 12-punctata 

 were abundant June 9. Two days later great numbers of English sparrows were 

 observed on the shoots, and in places where they had been few larvae or beetles 

 remained ; apparently they had been eaten by the birds. 



A most annoying and destructive imported pest, the elm-leaf beetle, 

 seems to have few bird enemies. The bird oftenest reported to eat it 

 is the cedar bird (Bomby •cilia cedrorum). Outram Bangs reports that 

 during midsummer, 1903, a row of about a dozen young elm trees at 

 Wareham, Mass., became very badly infested with the larvae and 

 adults of the elm-tree beetles {Galerucella luteola). At this time 

 the cedar birds discovered the beetles and came in parties of six or 



u Farmers' Bui. 54, p. 29, 1904. 



18 Bui. N. Y. State Museum, Vol. VII, No. 36, p. 1007, 1901. 



