Le mie anatre
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Vedi le FOTO - attorno ai laghetti
CaratteristicheI maschi hanno colori e disegni molto vistosi (nella stagione fredda). Verso giugno i maschi perdono le loro piume coloratissime e diventano molto simili alle femmine. Sono anatre timide. Se in piccoli gruppetti, tendono a nascondersi dall'uomo.
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When Europeans arrived in North America, they began to exploit the Wood Duck much more heavily than the Amerindians had been exploiting it, and since then, the Wood Duck has been a popular game duck, sought both for its flesh and its plumage. Hunting regulations were not effective in the early days of settlement, and by 1900 the Wood Duck had become scarce. In recognition of the need for protection, a total prohibition on hunting was enforced between 1918 and 1941. This joint effort was made possible by the Migratory Birds Convention of 1916 between Great Britain (on behalf of Canada) and the United States. As Wood Duck numbers have continued to grow following this protection, there have been increasingly liberal Wood Duck regulations since 1941.
An average of 1 189 000 Wood Ducks were taken by North American hunters annually between 1972 and 1989 – 121 000 in Canada and 1 068 000 in the United States. Continental populations are estimated to be between 2 and 4 million birds at the end of the American hunting season; this species is thus in a relatively secure position at present.
Wood Duck populations are limited by the availability and quality of habitat. People are the most important cause of mortality, chiefly by hunting; other mortality agents include nest predation by raccoons and bull snakes, disease, and parasitism. Wood Duck nests located in natural cavities or in well-protected artificial nest boxes have a higher hatching success than most duck nests; disease and parasitism are not usually important mortality agents, although diseases such as duck malaria (caused by the protozoon Leucocytozoon) and duck viral enteritus are known to affect Wood Ducks.
The Wood Duck, being a tree-nester, can easily be induced to nest in artificial nesting boxes, many types of which have proved successful. The Canadian Wildlife Service recommends nest boxes be at least 55 cm deep and 25 cm wide, with elliptical entrances of no more than 7.5 by 10 cm to reduce nest predation by raccoons. Raccoon predation on clutches within artificial nest boxes can also be reduced by placing boxes on posts or poles over deep water or wrapping sheet metal around the tree or post supporting the box. Starlings must also be discouraged from taking over the Wood Duck nesting boxes by making the entrance larger than they prefer. For optimum production it is important to maintain nest boxes on an annual basis. Maintenance should include replacement of shavings and ensuring that the box is sound and securely supported.
Although nest box programs can be very effective in increasing local breeding populations, the total population of Wood Ducks depends greatly on natural conditions. Federal, provincial, and state wildlife agencies can provide an abundance of the habitat essential to Wood Duck survival by maintaining over-mature trees in nesting areas, controlling pesticides, and preserving wetlands, particularly wooded swamps. When combined with hunting regulations based on reliable population estimates, these management policies ensure that Wood Ducks continue to be a source of enjoyment and a valuable resource in North America.