THE AMOUNT OF FOOD CONSUMED BY BIRDS. 65 



there were six, and from 2 to 3 there were six. Ten visits 

 , per hour was the average the day through. 



Over three-fourths of the food brought consisted of adult 

 grasshoppers, the great Carolina locust being often among 

 them. Half of the time two were brought at a visit. Only 

 a little calculation is necessary to show that each occupant of 

 the nest consumed about eighty insects that day, of which at 

 least sixty were grasshoppers. An average red-legged locust — 

 the species most commonly brought — weighs five grains Troy ; 

 sixty of them would weigh three hundred grains, and adding 

 the twenty-five per cent, consisting of worms, beetles, berries, 

 etc., we have four hundred grains as the weight consumed by 

 each nestling on that particular day. They were then about 

 ten days old ; their average weight was seven hundred and 

 eleven grains. Thus it appears that they ate per diem more 

 than half their own weight. 



Mr. Charles W. Nash 1 gives this experience with the food 

 of a young robin : " In May, 1889, I noticed a pair of robins 

 digging out cutworms in my garden, which was infested with 

 them, and saw they were carrying them to their nest in a tree 

 close by. On the 21st of that month I found one of the 

 young on the ground, it having fallen out of the nest, and in 

 order to see how much insect food it required daily I took it 

 to my house and raised it by hand. Up to the 6th of June it 

 had eaten from fifty to seventy cutworms and earthworms 

 every day. On the 9th of June I weighed the bird; its 

 weight was exactly three ounces ; and then I tried how much 

 it would eat, it being now quite able to feed itself. With the 

 assistance of my children I gathered a large number of cut- 

 worms and gave them to the robin after weighing them. In 

 the course of that day it ate just five and one-half ounces of 

 cutworms. These grubs averaged thirty to the ounce, so the 

 young robin ate one hundred and sixty-five cutworms in one 



1 Birds of Ontario, p. 22. 

 5 



