THE PRACTICAL VALVE OF BIRDS. 



:n 



The following table, combined from Aughey's report (106), shows the 

 average number (not percentage) of locusts, other insects, and other food 

 in stomachs examined by him : 



The sapsuckers, when they occur in any number, are apt to do con- 

 siderable damage. The United States Biological Survey recommended poi- 

 soning them, to which objections were made on the ground that the result 

 would be to poison hummingbirds and other birds which resort to the holes 

 made by the sapsuckers for sap. These objections have been answered 

 in a recent article by McAtee (107). 



MACROCHIRES-Nighthawks, Whip-poor-wills, Swifts and Hummingbirds 



Nighthawks have very large stomachs, proportionately, which are kept 

 filled to supply the motive power for their great activity. They feed almost 

 exclusively upon flying insects, 20,000 flying ants having been found in 87 

 stomachs, averaging 230 each, and ranging in 24 of the stomachs, from 200 

 to 1,800. They are known to take 600 species of insects. One contained 60 

 grasshoppers, another 22, another 19 (108). Harvey found 500 mosquitoes 

 in one stomach (109). Aughey (110) found 51 locusts and 10 other insects 

 in 6 stomachs. Although not hawks at all, it is said that under the hawk 

 bounty act in Pennsylvania thousands of dollars were paid in bounties on 

 nighthawks (111). 



The whip-poor-wills and poor-wills are almost entirely insectivorous. 

 During a locust invasion 2 whip-poor-will stomachs were both found to be 

 "crowded with locusts," and four-fifths of the contents of a poor-will stomach 

 was grasshoppers and locusts (112). 



The swifts are wholly insectivorous, taking in swift flight their prey, 

 which consists chiefly of small insects such as mosquitoes, gnats and flies, 

 though during locust invasions Aughey invariably found "more or less" locusts 

 in their stomachs (113). 



(106) Aughey, First Rept. U. S. Entom. Com.. App. II, pp. 40-42. 



(107) McAtee, The Auk, Vol. XXX, pp. 154-157, 1913. 



(108) Beal, Remarks on the Economic Value of Nighthawks, Nat. 

 Educational Leaflet No. 1 : Farmers' Bull. No. 513, p. 23. 



(109) Sullivan, Kas. St. Agric. Coll., Agric. Educ., Vol. Ill, No 7, p. 23. 



(110) Aughey, First Rept. U. S. Entom. Com., App. II, p. 39. 



(111) Pennock, Dela. St. Board Agric., Bull. No. 5, p. 13. 



(112) Aughey, Ibid., p. 38. 



(113) Aughey, Ibid., p. 39. 



Aud. Soc., 



