It is an inhabitant of woodlands and parks, depending for food and nesting sites upon old trees. It is often an inconspicuous bird, in spite of the plumage. The large white shoulder patch is a feature that catches the eye.
Great Spotted Woodpecker is 23-26 cm long, with a 38-44 cm wingspan. The upper parts of the male are glossy black, with a crimson spot on the nape and white on the sides of the face and neck. On the shoulder is a large white patch and the flight feathers are barred with black and white. The three outer tail feathers are barred; these show when the short stiff tail is outspread, acting as a support in climbing. The under parts are buffish white, the abdomen and under tail coverts crimson. The bill is slate black and the legs greenish grey,
The female has no crimson on the nape, and in the young this nape spot is absent, but the crown is crimson. It may be distinguished from the smaller Lesser Spotted Woodpecker by the crimson on the abdomen.
When hidden by the foliage, its presence is often advertised by the mechanical drumming, a vibrating rattle, produced by the rapidly repeated blows of strong bill upon a trunk or branch. This is not merely a mating call or challenge, but a signal of either sex. It is audible from a great distance, depending on the wind and the condition of the wood, a hollow bough naturally producing a louder note than living wood. The call is a sharp quet, quet.
The woodpecker usually alights on the trunk, working upwards, from side to side, but sometimes will perch in passerine style, when it sits well upright. During the ascent it taps the bark, breaking off fragments, but often extracts its prey from crevices with the tip of its sticky tongue. Beechmast, acorns, nuts and berries are eaten when insect food is scarce.
Its actions are jerky, and it hops rather than climbs, leaping forward with one foot just in advance of the other. When a space is crossed the flight is easy and undulating.
The nesting hole, neat and round, is bored in soft or decaying wood horizontally for a few inches, then perpendicularly down. At the bottom of a shaft, usually from six to twelve inches in depth, a small chamber is excavated, where on wood chips the creamy white eggs, five to seven in number, are laid in the second half of May.
The hole is rarely used again, but not infrequently other holes are bored in the same tree. Almost any tree sufficiently rotten is used. The young, when the parents are feeding them, cluster at the mouth of the hole and keep a continuous chatter, but when alarmed slip back into the hole.