Wyoming Birds. 31 



ARDEIDAE (Herons, Egrets, Bitterns,' etc.) 



The Herons feed mostly upon frogs, fish, snakes, and crustace- 

 ans. They also destroy large numbers of grasshoppers and mice. 

 The Black-crowned Night Heron and the Great Blue Heron are 

 the only ones of this family which occur in Wyoming in sufficient 

 numbers to be of any economic value. Both are known to feed 

 largely on grasshoppers and mice when these pests are abundant. 



References : 



1. Bulletin No. 20, State Geological and Natural History Sur- 



vey of Connecticut, 1913, pp. 265-266. 



2. University of California Publications. 



3. Bulletin 31, U. S. Biological Survey, p. 52. 



4. Bulletin 38, U. S. Biological Survey, p. 26. 



190. Botaurus lentiginosis: Bittern. 



Common summer resident in southern Wyoming. Less 

 common in the northern portion of the state. 



191. Ixobrychus exilis: Least Bittern. 



Lockwood reports a specimen from the vicinity of Lake 

 Como. At Cody there is a mounted specimen that was 

 probably taken near there. Knight reported it as acci- 

 dental, a specimen having been taken near Cheyenne. 



194. Ardea herodias herodias: Great Blue Heron. 



Abundant summer resident of the lower altitudes of the 

 entire state. 



197. Egretta candidissima candidissima: Snowy Egret. 



The records for this bird are Lake Como, by Lockwood, 

 and Bamforth Lakes, by Walker. Knight reports one in 

 his book and mentions in a more recent note that one was 

 taken at Walden, Colo., in 1901. 



201. Butorides virescens: Green-Heron. 



The first record of this species is from Laramie County, 

 near the Nebraska line, by Clearwaters. 



202. Nycticora nycticora naevius: Black-crowned Night Heron. 



Quite common in suitable localities across southern Wyo- 

 ming. Knight recorded it as being rare, but it is evidently 

 increasing. 



