18 CUCKOOS AND SHRIKES IN RELATION TO AGRICULTURE. 



destroyed by the butcherbirds, if allowed to live, would have amounted 

 at the end of the first year to 118,800, and at the end of the second year 

 to 1,306,800 individuals. The shrike is at work every winter in the 

 cities of the northern tier of States, killing the sparrows which tend to 

 increase until they become so abundant that more are obliged to resort 

 to the country for food. In a number of instances where English spar- 

 rows had been devoured, their stomachs, containing seeds and gravel, 

 were found within the butcherbirds' stomachs. A golden-crowned 

 kinglet's stomach also was detected, filled with fragments of a beetle 

 and scores of tiny gnats. Mr. Frank M. Drew, in an article entitled 

 'Field Notes on the Birds of San Juan County, Colorado' (Bull. Nutt. 

 Ornith. Club, vol. G, p. 89), says that this shrike lives by foraging on 

 little troops of titmice. Dr. G. S. Agersborg, of South Dakota, states 

 (The Auk, vol. 7, p. 279) that it seems to follow the wake of the tree 

 si)arrows {Sjnzella nwntieola), and leaves in the spring at the same time 

 they do. Prof. F. E. L. Beal while at Ames, Iowa, noted the butcher- 

 bird attacking birds onlj- once, although he had time and again recorded 

 tlieir killing mice. In this excei)tional case the victim was a downy 

 woodpecker {Dryohntes pubcscens) which the shrike had hung in a crotch 

 while devouring the brains. The most remarkable account of the 

 butcherbird's not molesting biids also comes from Professor Beal at 

 the same station. A shrike was perched on a telegraph wire above 

 a rank weed patch which was all a-twitter with hundreds of native 

 sparrows. Every now and then the shrike would leave the wire to 

 scour the jjrairie, apparently hunting for mice, and then return to his 

 perch. He paid no attention to the si)arrow8, and they showed no 

 signs of apprehension. 



Following is a list of biids that the butclierbird lias been known to 

 kill : 



Chickadee {I'anm atrirapilliin).' 



Bush tit {PxaltrijmrHx). 



Enjjlish sparrow (Paxner domenUcti^):- 



Tree sparrow {Sj>i:ella monticola).- 



Snowflake {Plectrophenax niralifi). 



Downy woodpecker {Dryohatex piihexmHn). 



Vireo ( Virvo sp.)- 



.lunco {.Tunco hycmalin):- 



Kinglet {RefjuluH xatrapa).- 



Field sparrow (Sphella puniUa).' 



(ioldfinch (.Sj>ijiH« tristis).'- 



Siskin {Sj)inuK pinu»).- 



Yellow-rnmpcd warbler {Dendroica coronala):- 



Mourning dove {Zexaidina macronra). 



Cardinal {Cardinalis cardinalin). 



Longspur (Calcarius).-^ 



Shore lark (Olocoris).-^ 



' Dr. J. Dwight, jr. -Idrntitied in the laboratory. 



'Ornithologist and Oologist. 



