Incredibly rare white sparrow pictured in Cardiff park

An extremely rare white sparrow has been spotted in Cardiff. The unusual white-feathered bird was spotted in a garden near the city's Roath Park earlier in May.

The white sparrow was spotted with one of its more common counterparts when it was photographed. According to the RSPB, monitoring suggests a "severe decline" of the house sparrow population in the UK, estimated as dropping by 71 per cent between 1977 and 2008 with "substantial declines in both rural and urban populations".

White sparrows are even less common than white blackbirds. Leucism is a genetic condition which results in a partial loss of pigmentation and in birds the lack of cells responsible for melanin production often leaves their feathers white or washed out in colour.

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The sparrow was spotted near Roath Park (ugc)

White sparrows are even rarer than white blackbirds (ugc)

An RSPB Cymru spokesperson said: “The house sparrow seen in this image is most probably leucistic. Leucism is a genetic condition that causes feathers to turn white because of a lack of melanin pigment. Although leucism is a rare condition, it is much more common than albinism.”

The genetic condition results in a partial loss of pigmentation and is inherited, but the extent and positioning of the white colouration can vary between adults and their young. This means in some birds their feathers may not appear completely white but pale or washed-out in colour.

Due to the lack of pigment in these birds, their feathers are more prone to wear and can weaken more easily. However, the chances of survival for leucistic birds are low, as their distinctive whiteness can make them a target for birds of prey. In some scenarios, leucistic birds also may not be recognised or accepted by a potential mate, according to the British Trust for Ornithology.

Leucism differs from albinism as leucistic birds are not completely without pigmentation and may simply appear lighter than usual. Albinism results in white feathers, but is caused by a genetic mutation where there is a total lack of melanin. Additionally, albino birds will have pink or red eyes, while the iris pigmentation of leucistic birds remains dark.