Several species of woodpeckers search for wood-boring beetle larvae by removing the bark from a tree (in addition to drilling holes). This is referred to as bark sloughing. Some birds, such as nuthatches, remove only scales of bark, not the whole layer like woodpeckers, and this is referred to as scaling. After finding or creating an opening, a woodpecker repeatedly slips its pointed beak under loose bark, prying it off of the tree. It then uses its long, barb-tipped tongue to capture the exposed insects. Different woodpecker species tend to feed on either trunks or branches, and at different heights. Initially sloughing can resemble the work of porcupines, but close examination can reveal the marks of a beak, which are perpendicular to the trunk or limb, rather than the grooves left by a beaver’s incisors.
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