64 BULLETIN 621, U. S. DEPARTMENT OF AGRICULTURE. 



A brood of four secured in Michigan illustrates this point. Not- 

 withstanding the fact that frog remains occurred in the stomach of 

 each and averaged over 50 per cent of the food there was no evi- 

 dence that more than two individuals had been eaten. Each of 

 another brood of five collected in Vermont also had frog remains in 

 its stomach and, as the average portion for the lot was only 18 per 

 cent of the stomach contents, one frog may well have furnished the 

 food for all. Two half-grown young, also from Vermont, had eaten 

 a toad, frog, and salamander between them, which constituted 51 per 

 cent of their diet. Another week-old hatch of three from the same 

 place also had the remains of probably one frog shared among them. 

 Five J^oung secured in Dallas County, Mo., had all fed on frogs and 

 toads, probably three or four individuals being eaten. Each of five 

 others from the same place had fed on amphibians, a salamander and 

 more than one frog being identified. In one instance, where even 

 the skin of a freshly eaten specimen was still present in the stomach, 

 the frog remains formed as much as 83 per cent of the food. 



WILD BIRDS AND THEIR EGGS. 



The remains of w T ild birds and their eggs formed 1.57 per cent 

 of the food of nestling crows. Birds were found in 53 of the 778 

 stomachs, but in four cases the material could not be distinguished 

 from the remains of poultry. Eggs of wild birds were present in 20 

 stomachs. In two instances the remains of both a wild bird and eggs 

 were found in the same stomach, so the total record of such car- 

 nivorous habits, on the part of nestling crows amounts to 71 out of 

 778 stomachs, an average of about 1 in 11. This ratio, when com- 

 pared with 1 in 28i| for the adult, probably closely represents the 

 relative activity of old and young in the destruction of bird life. 



As in the consumption of other vertebrate remains, crows fre- 

 quently feed parts of the same individual to more than one nestling, 

 which results in duplication when a count is made of the number of 

 stomachs in which certain items are found. A brood of 4 or 5 may 

 each have fed on the body of a nestling robin, yet only one act of 

 vandalism on the part of the parent supplied the food. Although 

 71 young crows had partaken of wild birds or their eggs, only 44 

 broods were involved. While in a few instances more than one bird 

 or clutch of eggs may have been present in the stomachs of one brood, 

 the habit of passing around parts of the same individual seemed to 

 be common. It is apparent, then, that the ratio of 71 to 778 is an 

 ample one and that it may be reduced even more than has been indi- 

 cated when it is considered that in several cases the parents of the 

 broods also had shared with their young parts of the same food. 



Each one of a brood of four collected in Kansas had been fed on 

 what appeared to be a song sparrow, and two of the four stomachs 



