VIRGINIA – Tap-tap-tap, rap-rap-rap. Out in our Northwoods that only can mean one thing, a woodpecker is nearby. Several kinds of woodpeckers are on the shortlist, birds that spend the entire winter here. It seems odd that some of our common birds feed mostly on insects even during the winter. What do they find up there in the trees?
During the winter months insects seem totally nonexistent to us. The lack of insects, jokingly, is considered one of the pluses of winter. However, certain birds rely on their ability to find insects for survival. And, most of these birds in our Northwoods never encounter a birdfeeder! Even if a woodpecker does eat at a birdfeeder, insects still are needed in its diet.
Among the most common insects that woodpeckers know how to find are beetles. Many species live on, or in, the trees. Beetles are among the insects that have four distinct stages during their lives: egg, larvae, pupa, and adult. During the winter months most beetles exist as larvae, which in the case of beetles, usually are called grubs. Most of these resemble the familiar May beetle grubs we encounter while digging in our yards or gardens. However, there are many kinds of beetles, and their grubs vary greatly in appearance from species to species. Some look more like little lizards or other oddlooking beasts.
The beetles that woodpeckers depend on live inside the trunks of trees as grubs. Many live just beneath the bark, where they chew tunnels. Others tunnel through the interiors of the tree trunks. Others feed on dead and rotting wood. One of our less common woodpeckers, the black-backed woodpecker, specializes on beetles that prefer sites of recent forest fires. Amazingly, beetles are among the longest living insects. Some that burrow in tree trunks live as grubs for several years!
Beetles are not the only bugs eaten by woodpeckers. Ants are favored by some, especially by pileated woodpeckers, the largest in our Northwoods. During the winter these ants and their eggs are found in the base of the tree trunk or in the upper parts of their roots. As a result, pileated woodpeckers, and their excavations, commonly are encountered low on the trees—often very near the ground.
Feeding is not the only reason for woodpeckers pecking on the trees. In the late winter and spring woodpeckers sometimes are very loud, with rapid pecking. This is part of their mating and territorial behaviors. This is the way they proclaim their territories.
Woodpeckers are one of the most interesting animals in our Northwoods. It is interesting to watch them and ponder what it is they are finding to eat. Most of the time, one first spots a woodpecker after hearing it. Another example, the slower you go, the more you see— and hear.
Jerry McCormick lives in Virginia, MN. He is a retired natural resources professional and is a self-described nature nerd.