This little blackbird was singing its heart out this evening near our house. It ‘should’ be black, and nearly all blackbirds are black (females are brown). But this guy is leucistic, meaning that it has an inherited condition that causes a lack of pigment in the cells responsible for melanin production.
It is said that the reduction of pigment in leucistic birds causes their feathers to weaken and be more prone to wear. Leucistic birds are usually more conspicuous, which puts them more at risk from predators. There is also evidence that leucistic birds might be less acceptable to potential mates.
Well, yes and no. Being an hereditary deficiency, you would have thought that leucistic birds would have died out with no one to carry the defective genes if the problem were that serious.
Perhaps the leucistic birds get help from their fellow blackbirds? We are learning how much cooperation there is between animals, and trees.