56 FOOD OF BOBOLINK, BLACKBIRDS, AND GRACKLES. 



Mr. W. B. Hall, of Wakeham, Ohio, gives an interesting account 

 of some 3^oung grackles which were kept in captivity. He says: 



I have captured the young and confined them in a cage in such manner that the 

 old bird could not reach the mouth of the young. The food brought consisted 

 largely of larvae of Coleopterous and Lepidopterous insects, with an occasional beetle. 

 If freshly j)lowed fields were in the vicinity the food consisted largely of the white 

 grub and cutworm, a few tent caterpillars, one worm that I took to be a small Aitacus, 

 and beetles of the genera Galeriia, Cetonia, Lachnosterna, and their kindred. 



An estimate of the amount of food required to support a large flock 

 of blackbirds has been made by Mr. H. H. Johnstin, of London, Ohio. 

 During the autumn of 1894: he counted 1,100 blackbirds one morning 

 as they left their roosting places for the feeding grounds, and esthiiated 

 the birds which flew by at 50,000. Allowing 2 ounces as the quantity 

 of food collected by each bird during the da}', he arrived at the con- 

 clusion that 0,250 pounds, or more than 3 tons, of food was consumed 

 by this arm}' of blackbirds in a single day. Even if the number of 

 birds in this case is not overestimated, the amount of food per bird is 

 undoubtedly too great. The species of blackbirds to which these notes 

 refer are not stated, but it is safe to assume that the flocks were 

 made up of redwings {Agelaius) and crow blackbirds {Qulscalus). A 

 full stomach of the crow blackbird, selected at random from specimens 

 in the collection of the Biological Survey, was found to weigh 0.158 

 ounce, or 2.53 drams, Avhile the contents of another stomach weighed 

 only 0.116 ounce, or 1.85 drams. The average of two full stomachs 

 of red-winged T)lack])irds was 0.049 ounce, or 0.78 dram, and the 

 stomach contents of a third weighed only 0.021 ounce, or 0.33 dram. 

 While of course these iiguri's do not give the quantity of food a bird 

 consumes in twenty-four hours, they show that the full stomach of a 

 blackbird weighs comparatively little. In order to consume 1 ounce 

 of food per day a crow blackbird nuist eat six or eight full meals, 

 according to the kind of food, and the redwing three or four times as 

 many. At this rate the amount consumed by the flock of 50,000 birds 

 would be about a ton and a half pei' day. These figures arc undoubt- 

 edly still too large, but they serve to give a slight hint of the quantity 

 of grain a large flock could destroy. 



The accusations against the crow blackbird, briefly stated, relate 

 mainly to the destruction of grain, especially corn, soOn after planting 

 in the spring, and again in the autmnn, when the corn is 'in the milk' 

 and nearly ripe. In the Southern States rice is also destro}ed by 

 grackles. In some sections they are said to feed upon yoiuig grain in 

 such quantities as seriously to injure the value of the crop, and for this 

 reason they are poisoned in large numbers. A more efi'cctual method 

 is to prevent the birds from taking the seed by tarring the corn before 

 it is planted. This is better, simpler, and cheaper than the wholesale 

 destruction of the birda. 



