56 FOOD HABITS OF THE GROSBEAKS. 
Colorado potato beetle. Two stomachs of nestlings contained this lat- 
ter nauseous insect. larve being found in one, adults in another. 
Wasps composed almost half of the food of one fledgling, and a 
weevil and some small cocoons constituted the remaining animal 
matter. 
Pa-sing from these results of actual stomach examination to the 
experiences of observers, it should be noted that the rosebreast’s 
habit of feeding its nestlings the larve of the potato beetle is fre- 
quently recorded. This fact is one of the best evidences of the 
importance of this beetle in the grosbeak’s regimen. Prof. F. E. L. 
Beal* speaks of a small potato field, which earlier in the season 
was so badly infested * * * that the vines were completely rid- 
ded. The gro-beaks 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.” Prof. E. F. Hitchings, State entomologist of Maine, 
gives the following interesting note: 
several years ago I observed a pair nesting in a clump of trees in * * * 
Waterville. A piece of potatoes was planted near by, and I watched the parent 
birds as they fed their young on the larve of the Colorado potato beetle. I 
examined the bills vf the young and found them stained and even dripping with 
the juice of the insects. It took a great many young larve to satisfy them. 
(May 19, 1906.) 
When we reflect that every year there are thousands of grosbeak 
families throughout the breeding range of the species doing exactly 
the -ame thing. it can not be doubted that they exert a marked effect 
on the numbers of the potato beetle. 
The voracity of nestlings is proverbial, and their lusty appetites 
greatly enhance their value as destroyers of injurious insects. The 
number of insects eaten daily by nestlings has been recorded in the 
case of but few birds; hence we are fortunate in having E. H. For- 
bush’s account of a study of the nestlings of the rosebreast: 
On June 12, 180. Mr. Mosher watched the nest of a pair of rose-breasted gros- 
beaks trom early morning to 5 p.m. * * * For the first half hour the old 
birds were so excited by his presence that the feeding of the young birds was 
interrupted, so that no notes were taken until 6 a. m., and none were taken after 
5 p.m. The old birds visited the nest— 
Times. , Times 
Between 6 and, 7_.-222s-<2es--== 502 | Between 12 and 1_______________ 30 
Between 7 and S%__..--..--..----. +7 | Between 1 and 2________________ 38 
Betweeiss ‘aids Ws 22S eno oes 43 | Between 2 and 3_______-_________ 41 
Between 9 and 10 .22..---+2s--<- 30 | Between 3 and 4-__--___________ 22 
Retween 10 and 1i_-----_----_--- 36 | Between 4+ and 5__--_____________ a8 
Between 11 and 12____-______-__ in 
making altogether 426 visits during the portion of the day that they were 
watched. The food was mainly caterpillars of one kind or another, and there 
*Farmers’ Bull. 54, 1904, p. 35. 
