The hairy woodpecker forages along tree trunks and the main branches of large trees (2), searching for the insects that make up more than 75 percent of its diet (2) (4). It mainly takes the larvae of wood-boring beetles and bark beetles and the pupae of moths (2), but ants are also a key food item, and other invertebrates such as bees, wasps, spiders, millipedes and caterpillars are eaten in smaller quantities (2) (4) (6).
To find its prey, the hairy woodpecker uses a variety of techniques. It will usually either glean insects from the surface of the bark, or locate prey hidden within the tree by rapidly tapping along a branch or trunk, detecting differences in resonance which might signal the presence of a wood-boring insect tunnel. Once a prey item has been detected, the hairy woodpecker chisels away at the wood to excavate it (4) (9), and then extracts it using its long, barb-tipped tongue (8).
As well as insects, the hairy woodpecker also consumes fruits, seeds, acorns and nuts (4) (6) (9). This species is known to drink sap from wells made in the bark by sapsuckers (Sphyrapicus spp.) (2) (4) (8), and has been reported to peck into sugarcane to extract the sugary juice (2) (4).
The hairy woodpecker moves up tree trunks by means of ‘hitching’, which involves making its way up the bark in short leaps (8), using its stiff tail feathers both as support and as a spring to aid its upward movement (2) (4). Generally a solitary bird, the hairy woodpecker characteristically roosts and sleeps alone in a cavity that it has excavated (4).
This monogamous species (4) usually locates a territory and forms a pair bond with a mate by early spring (4) (8). Although the timing of nesting varies depending on the location, it generally occurs between late March and early June (4).
The hairy woodpecker nests in a cavity excavated within a tree trunk (2) (6). The female lays a single brood of between 3 and 6 white eggs (2), which are incubated by both sexes (8) for 11 to 12 days (2) (4). Both the male and female feed the young (4) (8), which fledge the nest after about 28 to 30 days (2) (4).