描述鸟类
请在 dove / owl / ostrich / woodpecker / wild goose / seagull
中选两个用英文 English 描述其外表、特点、栖息地和食物等方面。
参考答案:【Great Spotted Woodpecker】（大斑啄木鸟）
In recent times the great spotted has become the most familiar woodpecker due to regularly visiting bird-tables in observers' gardens. This bird is distributed over an immense range covering almost the entire Palearctic from Britain in the west to Japan in the east and reaching North Africa and the Canary Islands in the south-west.
As expected in a generally sedentary species with such an extensive range, the great spotted has been separated into a number of distinct sub-species both in size and in plumage as well as in length and shape of bill.
As many as 14 races are described in Woodpeckers, Piculets and Wrynecks of the World (1996). This magnificent volume extends to more than 400 pages.
When searching for food a great spotted woodpecker usually alights on the trunk then works upwards and often from side to side. During the ascent it smartly taps the bark, prising off fragments and frequently extracting food from crevices with the tip of its sticky tongue.
Actions are jerky and the bird hops rather than climbs even when beneath a branch. It will work round to the further side of the trunk, often apparently to avoid observation.
The great spotted has a varied diet changing with the seasons. During spring and summer it feeds largely on insects, especially ants and the larvae of wood-boring beetles. Holes may be chiselled up to four inches deep. But in autumn and winter the birds switch to a variety of fruits, seeds and nuts.
Unwieldy nuts and pinecones are placed in clefts and hammered open with the bill. Particular trees are selected and the remains of food may be found scattered below these "anvil" trees. Some anvils have been used for years.
Local observer, Nat Tracy, who lived at South Wootton, has described how a great spotted worked 3021 cones between August 13 and October 30. Thirty-two anvils were available to the bird although it mainly used just four or five.
Another ornithologist recorded a single woodpecker which used two adjacent anvil trees and dealt with some 2000 cones in a single winter.
A cone is harvested by the woodpecker holding it with one foot while attacking the stalk until it breaks. After wedging the cone in the anvil it is worked by rotation at regular intervals in order to obtain the seeds from all sides.
Although feeding their own young largely on insects and spiders, great spotted woodpeckers are notorious for taking the eggs and young of other hole-nesting birds (especially tits and house martins).
At night this woodpecker roosts singly in tree holes. Where suitable ones are not available special holes are excavated.
A male great spotted wood-pecker has made regular early morning visits to a nearby towering beech. One branch, long dead, has provided a drumming post. The vibrating rattle produced by an extremely rapid rain of blows with the bill is audible from a great distance.
If the "sounding board" is of the right condition it may be heard up to a distance of half a mile. Both sexes in fact drum, commencing in January and continuing until late June. Usually a new nest is bored each spring rarely less than 10 to 12ft from the ground and often considerably higher.
Both parent woodpeckers excavate and this task occupies between two and three weeks. The creamy white eggs, five to seven in number, are laid during the second half of May. But many pairs are dispossessed by starlings and unable to breed until early June.
When the same tree is used in consecutive years the new hole is usually below that of the previous year.
My earliest diary records watching great spotted woodpeckers displaying. High-speed spiral pursuits round and round the branches of a silver birch occupied several minutes. On another occasion a pair launched themselves from the tree before flying in a very slow quivering manner with crown feathers raised and tail widely spread.
In parts of the country, great spotted woodpeckers regularly attack wooden nest-boxes. The eggs and more commonly the young of blue tits, great tits, coal tits and nuthatches have all become victims. The woodpeckers gain access to the nest either by enlarging the box entrance or by drilling through the side of the box on a level with the contents.
These woodpeckers have also regularly attacked colonies of nesting house martins by clinging to the side of the inverted mud dome and chipping away a hold. Other victims have included young treecreepers and house sparrows.
It was at one time suggested that it is the sound of nestlings within the boxes which result in attacks. However some entrance holes have been enlarged by woodpeckers during the winter, possibly for roosting.