WOODPECKER FAMILY. 17 



SUMMARY. 



The above brief review of the food of the hairy woodpecker indicates 

 that nearly half its yearly food consists of larvae of some of the 

 most destructive insects known, while this service is not offset by the 

 destruction of any useful product. The other elements of the bird's 

 food are either beneficial or neutral. It is unfortunate that the species 

 is not more abundant on the Pacific coast. 



DOWNY WOODPECKER. 

 (Dryobates pubescens gairdneri and other subspecies.) 



To the ordinary observer the downy woodpecker is only a miniature 

 edition of the hairy, which it resembles in everything but size. It 

 seems, however, to be far more abundant than its larger relative, 

 especially in California. It is much more domestic than the hairy, 

 and frequents orchards and gardens and the vicinity of houses. Its 

 food consists of the same elements but in different proportions. The 

 following report is based on an examination of 80 stomachs, taken in 

 every month of the year. The food consists of 77 percent of animal 

 matter to 23 of vegetable, thus agreeing closely with the diet of the 

 hairy. 



Animal food. — The animal food is composed of insects, with a few 

 spiders. The western downy eats 16 percent of wood-boring larvse, 

 a little more than the eastern downy, but less than one-third as much 

 as the hairy woodpecker. Other beetles amount to 13 percent. They 

 are mostly harmful species, the exception being a few Carabidae, or 

 predaceous ground beetles. 



Ants are eaten to the extent of 12 percent, which is less than half 

 the quantity taken by the eastern subspecies. While ants may some- 

 times subserve a useful purpose, they are for the most part annoying 

 or noxious. It is well known that they protect and foster plant lice, 

 and they often injure timber by boring galleries through it, frequently 

 beginning in the abandoned burrow of a beetle larva. In houses 

 they are an unmitigated nuisance, and in gardens and lawns are often 

 equally obnoxious. For these reasons the habitual destruction of 

 ants by woodpeckers is commendable. Other Hymenoptera amount 

 to less than 2 percent, and consist of wasps and wild bees. 



The largest item in the food of the downy is made up of caterpillars, 

 pupae, and a few adult moths. These aggregate a little over 21 per- 

 cent. Pupae of the codling moth were identified in 4 stomachs and 

 the larvae in 2, of which one contained 16 entire full-grown larvae. 

 Another held the remains of 20 of these pernicious insects. From 

 investigations during the past few years it appears that birds con- 

 stitute a most efficient natural check to the spread of this destruc- 

 tive moth, especially such birds as woodpeckers, titmice, nuthatches, 

 and creepers, which obtain much of their food from crevices in the 

 38301— Bull. 34—10 2 



