Woodpecker: The forest construction crew with a built-in crash helmet

The woodpecker is the forest's most unusual "doctor" and "construction crew": it hammers at trunks with a rat-a-tat-tat that sounds forceful, yet its head never seems to suffer. Why? Let's meet it.

Its body

The woodpecker measures about 20 to 25 centimetres, with a straight, hard bill like a chisel. It can strike a trunk many times a second, and each impact hits with several times the g-force of a rocket launch — yet inside its skull sits a crash helmet: the bone is full of spongy holes that cushion the shock, and its extra-long tongue wraps right around the head like a seat belt to soak up the impact. It also has two toes forward and two back, gripping bark like pliers, while stiff tail feathers act as a third foot to prop up the body.

Where it lives and what it eats

The woodpecker is an omnivore, feeding mainly on insects and grubs beneath the bark, plus fruit, seeds and sap. One of the main reasons it drums is to find the grubs hidden in the wood. It usually hollows out a nest hole in a trunk.

The gift it gives the forest

The holes a woodpecker carves often become another animal's home the following year — owls, squirrels and small birds may all move in. That is why the woodpecker is called the forest's "chief construction crew": it does not only build for itself but quietly provides the whole forest with a set of public housing.

A note for grown-ups

You could listen for the "tok-tok" in a park with a child and then hunt for holes in the trunks. Tell your child that those holes are not only the woodpecker's home but also homes for other forest residents. Helping a child grasp how animals affect one another is a wonderful insight.