| Habitat and Ecology: |
Behaviour The species is sedentary on Atlantic islands1, 3 and in some areas in south-western maritime countries4 but is otherwise strongly migratory1, 3. The spring migration starts at the end of February11 (the timing of this movement being closely related to temperature), with the species arriving on the breeding grounds between March and mid-May. In Europe, the species breeds from the end of February to July1. The autumn migration to the wintering grounds is largely governed by the timing of the first winter frosts (e.g. from October to November)1. The species is typically solitary and usually migrates singly or in groups of 5-64. Individuals may also become aggregated by topography or weather conditions, especially when migrating overland or where food and shelter are restricted4. It typically forages nocturnally during the winter1. Habitat The distribution of earthworms is an important habitat characteristic for the species throughout the year2. Breeding For breeding the species requires extensive unfragmented areas1, 3 of broadleaved deciduous or mixed broadleaved/coniferous forest2 containing a dense undergrowth of shrubs and ground cover10 (e.g. of brambles Rubus spp., holly Ilex aquifolium, hazel Corylus avellana, gorse Ulex spp., bracken Pteridium spp. or bilberry Vaccinium myrtillus)1, 10 and with a mosaic1 of dry, warm resting places, moist areas for foraging2, 3 (e.g. streams, springs or damp, swampy patches)1, and clearings or other open areas as flight paths2, 3. The species may also nest in swampy forests with mossy ground, brooks and other watercourses or alternatively in coniferous forest with moist leaf litter and an undergrowth of broadleaved shrubs and ferns2. Non-breeding The species's habitats requirements during the daylight hours of the non-breeding season are similar to its breeding habitat requirements but are less restricted1. As well as extensive broadleaved or mixed broadleaved/coniferous forest2 the species will also occupy young conifer plantations1, hedges with high densities of trees and shrubs9, smaller woods, areas of scrub3 and coppiced habitats with coppice of between 7 and 20 years old1. It still shows a strong preference for woodlands with rich (e.g. mull) humus types that have high earthworm biomasses, and a dense shrub strata however9. At night during this season the species gathers to roost and feed in damp, earthworm-rich, permanent grasslands1, 3, 9 sometimes 3-4 km away from woodland areas used for cover during the day3, showing a preference for grazed meadows compared to cultivated fields (as the latter contain higher earthworm biomasses)9. The species may also feed on intertidal mud during freezing weather3. Diet Its diet consists predominantly of earthworms, especially during the non-breeding season1, but the species may also take adult and larval insects (e.g. beetles, earwigs and millipedes), spiders, slugs, leaches, ribbon worms1 and plant material such as seeds, fruit, agricultural grain (e.g. oats and maize), and grass roots and leaves1. Small freshwater bivalve molluscs and crustaceans are also taken by migrating birds2. The composition of the diet may differ between the sexes1. Breeding site The nest is a shallow depression in the ground concealed by shrubs1 in open wooded sites2, often at the base of a tree or near a dead fallen branch or log2. Management information In France, both wintering and breeding populations have been monitored since the beginning of the 1990s12; in autumn-winter, the monitoring is based on indexes of abundance from data collected by hunters (approx. 1,000) and ringers (approx. 400); in spring, the monitoring is based on censuses of roding males in May-June carried out by a network of 400 observers; wintering population seems to be slightly increasing (1992-2007). Annual success of reproduction is estimated from analysis of wings collected by hunters (mainly in France12 and Denmark13) and from ringing data (5,000 individuals every year in France). Hunting bags are regularly estimated in some Europeans countries, especially in Denmark13, in the European part of Russia14, in Finland, in Sweden15 and in Switzerland. The annual European hunting bag is estimated at 3-4 million birds15. Bag limits are applied in different European countries, especially in France, Italy and Portugal15. In Britain an appropriate method of surveying the species was found using data on seasonal and evening patterns of summer male display7. It was found that in Britain the best months for surveying the species are May and June, and that the detection of 83% of male passes at a fixed point should be possible in a survey lasting 1 hour and commencing 15 minutes before sunset7. There is evidence from France that hunting reserves may be efficient tools for conserving wintering woodcocks, but only if buffer zones at least 1 km wide where hunting pressures are kept low and under-control are in place around reserves8. In France it was also found that forestry management practices should preserve rich humus types and coppices by choosing tree species that ameliorate the soil and by soil tilling9. The species may also benefit from set-aside land, grass field-borders and the simplification of farm practices (e.g. by reducing soil tilling and direct sowing)9.
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