Great spotted woodpecker

This woodpecker occurs in all types of woodlands and eats a variety of foods, being capable of extracting seeds from pine cones, insect larvae from inside trees or eggs, and chicks of other birds from their nests. It chisels into trees to find food or to excavate nest holes, and drums (drumming) on favoured trees to contact others and to establish territorial claims. Like other woodpeckers, they have adapted with anatomical changes to compensate for the physical stresses of the hammering action. It breeds in holes excavated in trees, unlined apart from wood chips. The typical clutch is four to six glossy white eggs. Both parents incubate the eggs, feed the chicks, and keep the nest clean. When the young first leave the nest, they are fed by both parents for about 10 days and each parent will assign themselves for feeding part of the brood.

It spends much of its time climbing trees, and is well adapted to this lifestyle. Many of these adaptations are shared by other woodpecker species including the arrangement of toes with two facing forward and two facing back, their stiff tail feathers are used as support against the trunk of the tree. Most birds have tail bones that reduce in size, but with woodpeckers the final vertebra is very large to support strong tail muscles.

The hammering of woodpeckers creates forces which are potentially damaging to the birds. In the Great-spotted Woodpecker and most of its relatives, the hinge where the front of the skull connects with the upper mandible is folded inwards, tensioned by a muscle that braces it against the shock of the impact when the bill is hammering on hard wood. The outer layer of the upper mandible is significantly longer than the more rigid lower mandible and absorbs much of the concussive force. Skeletal adaptations and strengthening also help to absorb the shock, and narrow nostrils protect against flying debris.

As well as using holes for breeding, great spotted woodpeckers roost at night, and sometimes during the day, in old nest cavities, even those excavated by other woodpeckers. They will occasionally make a new roosting hole or use an artificial site such as a nest box.