A nest box (or nestbox also called birdhouse) is a man-made box provided for animals to nest in. Nest boxes are most frequently utilized for wild and domesticated birds, but certain species of mammal may also use them. more...
Boxes are usually wooden, though some for birds are made from mixtures of wood and concrete, called woodcrete. Metal nest boxes are also marketed, but these are generally unsuitable for outdoor use, as they can overheat easily in sunshine.
The majority are cuboid, and many have a sloping roof. Many have a hinged top to provide access for cleaning, bird ringing or, when used for domesticated species, to give the breeder access to the young. Boxes may either have an entrance hole or be open fronted. Some nest boxes can be highly decorated and complex. Designs mimicking human house design or other structures are common in some gardens.
Different sizes of nest-box suit different species of birds with very small boxes attracting wrens and treecreepers and very large ones attracting ducks and owls. The maintenance of nest-boxes to remove old nest material and any parasites is important if they are to be successfully used. Budgerigars and some other birds raised domestically will not usually mate unless a nest box is available.
Bat boxes differ from bird nest-boxes in having a (usually) much smaller opening, often on the underside of the box. Populations of many bat species are becoming threatened because of ecological pressures and the provision of appropriate bat-boxes can held support locally important populations. Bats are also becoming popular sources of natural mosquito and insect control in some parts of the world. A single bat can eat 500 to 1,000 mosquitoes a night as well as numerous garden pests. Directions for making the open bottom bat houses for small and large colonies, as well as locations to purchase them are available on the internet. Bat houses are an ecologically friendly way of controlling mosquitoes as pesticides mostly kill the mosquito's predators rather than mosquitoes.
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