Brood patch

Area of bare skin on the underside of nesting birds

A brood patch, also known as an incubation patch, is a patch of featherless skin on the underside of birds during the nesting season. Feathers act as inherent insulators and prevent efficient incubation, to which brood patches are the solution. This patch of skin is well supplied with blood vessels at the surface, enabling heat transfer to the eggs when incubating. In most species, the feathers in the region shed automatically, but ducks and geese may pluck and use their feathers to line the nest. Feathers regrow sooner after hatching in precocial birds than for those that have altricial young.

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