Farmers are prone to look upon woodpeckers with suspicion. When the birds are seen scrambling over fruit trees and pecking holes in the bark, it is concluded that they must be doing harm. Careful observers, however, have noticed that, excepting a single species, these birds rarely leave any conspicuous mark on a healthy tree, except when it is affected by wood-boring larvæ, which are accurately located, dislodged, and devoured by the woodpecker.
Two of the best-known woodpeckers, the hairy woodpecker[55] ([fig. 20]) and the downy woodpecker,[56] including their races, range over the greater part of the United States. They differ chiefly in size, their colors being practically the same. The males, like those of many other woodpeckers, are distinguished by a scarlet patch on the head. An examination of many stomachs of these two species shows that from two-thirds to three-fourths of the food consists of insects, chiefly noxious kinds. Wood-boring beetles, both adults and larvæ are conspicuous, and with them are associated many caterpillars, mostly species that burrow into trees. Next in importance are the ants that live in decaying wood, all of which are sought by woodpeckers and eaten in great quantities. Many ants are particularly harmful to timber, for if they find a small spot of decay in the vacant burrow of a wood borer, they enlarge the hole, and, as their colony is always on the increase, continue to eat away the wood until the whole trunk is honeycombed. Moreover, they are not accessible to birds generally, and could pursue their career of destruction unmolested were it not that the woodpeckers, with beaks and tongues especially fitted for such work, dig out and devour them. It is thus evident that woodpeckers are great conservators of forests. To them more than to any other agency we owe the preservation of timber from hordes of destructive insects.
[55] Dryobates villosus.
[56] Dryobates pubescens.
Fig. 21.—Flicker. Length, about 12½ inches.
One of the larger woodpeckers familiar to everyone is the flicker, or golden-winged woodpecker[57] ([fig. 21]), which is generally distributed throughout the United States from the Atlantic coast to the Rocky Mountains. There it is replaced by the red-shafted flicker,[58] which extends westward to the Pacific. The two species are as nearly identical in food habits as their respective environments will allow. The flickers, while genuine woodpeckers, differ somewhat in habits from the rest of the family, and are frequently seen searching for food upon the ground. Like the downy and hairy woodpeckers, they feed upon wood-boring grubs and ants, but the number of ants eaten is much greater than that eaten by the other two species. Of the flickers’ stomachs examined, three were completely filled with ants. Two of these contained more than 3,000 individuals each, while the third contained fully 5,000. These ants belong to species which live in the ground. It is these insects for which the flicker searches when it runs about in the grass, although some grasshoppers also are then taken. The flicker’s habit of pecking holes in buildings sometimes greatly annoys his human friends, and it is particularly noticeable in the California species. Observation has shown that the object of the work is to obtain shelter for the winter. In the East most of the flickers are migratory, and only a few remain North where shelter is necessary. These generally find a safe retreat in the hollow tree in which they nested. In California, however, where the birds do not migrate, trees are not so abundant as in the East, and consequently buildings are brought into requisition, and in them holes are drilled, usually under the eaves, where snug nights’ lodgings are found. Often a dozen holes may be seen in one building. Barns or other outbuildings are usually selected, though churches sometimes have been used.
[57] Colaptes auratus.