BIRDS IN RELATION TO THE ALFALFA WEEVIL. 7 



carrion beetles (Silphidae and Staphylinidse), click beetles, dung 

 beetles (Aphodius), and weevils other than PJiytonomus were fre- 

 quent constituents of the remaining animal food. The vegetable 

 portion was either weed seeds or rubbish. 



Three of five killdeers obtained in May had fed on the weevil to the 

 extent of over 36 per cent of the food. In one, these insects composed 

 the entire contents, save a trace of darkling and ground beetles. It 

 required no less than 40 adults and 1 larva of the weevil to satisfj^ 

 this bird's appetite. Another had eaten 18 adults. 



Of the other food taken during May, spiders, ground beetles, 

 aquatic beetles, flies, bees, and wasps occurred in quantities decreas- 

 ing in the order named. The high proportion of spiders recorded 

 was the result of one of the birds having fed on them almost exclu- 

 sively. A few grain hulls in one stomach probably came from waste 

 material. 



The food for June, as learned from examination of eight stom- 

 achs, gives a good idea of what may be expected of the killdeer under 

 favorable conditions. The weevil formed nearly a third of the 

 monthly food, and was present in all of the stomachs but one. Of 

 two birds which had destroyed surprisingly large numbers of the 

 insect, one, from a newly cut field, had eaten 9 adults and 307 larvae, 

 and the other, feeding under similar conditions, had made away with 

 7 adults and 376 Iarva3. A third had taken 42 larvae and 1 adult. 



Of other animal food items for this month ground beetles occurred 

 in the greatest quantity. They were present in 6 of the 8 stomachs 

 and comprised over 15 per cent of the monthly food. Snails were 

 eaten extensively by two of the birds. Darkling beetles of the genus 

 Blapstinus were frequently taken and formed nearly 11 per cent of 

 the stomach contents. Dung beetles {Aphodius}, bill bugs (Spheno- 

 phorus sp.), caterpillars, and wasps were other common ingredients. 

 The vegetable portion was again unimportant, consisting entirely of 

 weed seeds and rubbish. 



The killdeer in no part of its extensive range is known to injure 

 farm produce. The worst that can be said of it is that in its indis- 

 criminate destruction of insects it may pick up a few that are bene- 

 ficial. These, however, form an extremely small proportion of the 

 bird's fare, while serious pests, as mosquitoes, craneflies, grasshop- 

 pers, and weevils of various kinds, are frequent components of its 

 food. In addition to this already exceptional record, the killdeer 

 must be considered as one of the most effective destroyers of alfalfa 

 weevils. In early spring the birds are frequent visitors of infested 

 fields, where many breeding weevils fall victims to the birds' voracity. 

 The killdeer has been rightly removed from the class of game birds, 

 where formerly it could be shot throughout much of its range. It 

 may now continue its good work unmolested. 



