126 SEVENTH REPORT OF THE FOREST, FISH AND GAME COMMISSION. 



beetle the principal part of its food whenever it can be obtained. A case which 

 came under my own observation will show how thoroughly they do their work. A 

 small field of about a fourth of an acre was visited by a pair of Grosbeaks as soon 

 as the potatoes were fairly above the ground. At first the beetles increased faster 

 than the birds could destroy them, but after the young of the birds had hatched the 

 beetles began to diminish, and by the time the young were able to fly the field was 

 clear — not a beetle was to be found."* 



This illustrates also the tendency of birds to prey upon some insect which, in 

 becoming unduly abundant, offers them an unusual supply of food. Birds, for 

 example, have been known to gather in great numbers to repel, as it were, an inva- 

 sion of grasshoppers. Quoting again from Professor Real's address: "Ground- 

 feeding birds eat these insects at all times when they can be obtained ; but in the 

 month of August, which is the month when they attain their maximum abundance 

 and frequently become a pest, nearly all birds, no matter what their usual food 

 habits may be, come to the ground and eat grasshoppers. Such birds as the Balti- 

 more Oriole, and the Cuckoo, which normally find their food upon the trees, change 

 their habits in August and leave the trees to forage upon the ground. A few years 

 ago, when the western part of the country was devastated by the Rocky Mountain 

 locust, it was found that nearly every species of bird, even the larger Hawks, and 

 Ducks and Geese, fed upon them to a considerable extent." 



One of the notable achievements of the economic ornithologist has been to 

 emphasize the value of seed-eating, birds, the Sparrows, Doves, Blackbirds and 

 others. It is a common error to believe that birds are of service to man only as 

 insect-eaters, and that the non-insectivorous species, if not harmful, are, at least, of 

 no particular use. But the fact is that these same insignificant looking Sparrows are 

 the farmers' best allies in his never-ending warfare against weeds. 



During the winter weed seeds form practically the entire fare of a number of 

 species of Sparrows; the seeds of amaranth, crab grass, ragweed, and pigeon grass 

 being the kinds devoured most frequently. 



Dr. S. D. Judd, of the U. S. Department of Agriculture, who has made a special 

 study of the food habits of seed-eating birds, states that i,ooo pigweed seeds were 

 found in the stomach of a Snowbunting killed at Shrewsbury, Mass., in February, 

 and that 700 seeds of pigeon grass were taken from a single Tree Sparrow ; and the 

 investigations of Professor Beal in the State of Iowa show that this species during 

 the period of its presence, from October until April, destroyed each year about 875 

 tons of weed seeds. 



* Proc. Twenty-fourth Annual Meeting New Jersey State Horticultural Society. 



