Australia's bird experts have had to trawl through the record books after the sighting of a rare black kookaburra in a Western Australian backyard.

Amateur photographer Mike (surname withheld) said he could not believe it when he looked out the kitchen window of his Manjimup property, about 300 kilometres south of Perth, and spotted the rare bird.

"I saw this black bird on the garden shed and I said to my wife 'Crikey, that looks like a kookaburra', and I knew it was by the beak," he said.

While sightings of black kookaburras have been recorded in parts of New South Wales, Victoria and Queensland, there is little evidence of the bird ever being spotted in WA.

Australian Birdlife magazine editor Sean Dooley has seen a lot of unique birds himself and through correspondence from his readers, but WA's black kookaburra had him trawling through his record books.

"The two reports of black ones I have are from Brisbane and Sydney areas, but none from WA," Mr Dooley said.

Sightings of black kookaburras have been recorded in parts of New South Wales, Victoria and Queensland, but there is little evidence of the bird being spotted in WA. ( Supplied: Mike )

One of country's first sightings was in WA

Bird experts around Australia agree the black kookaburra is very rare, but a WA-based ornithologist believes one of the country's first sightings was in Western Australia.

Department of Biodiversity, Conservation and Attractions ornithologist Allan Burbidge said the existence of a black kookaburra was first documented in Australian literature in 1951.

That bird was spotted in the WA town of Coolup, 100 kilometres south of Perth.

"There was a farmer named Angus Robinson in Coolup, and when it was brought to his attention he wrote it up in the Western Australian Naturalist," Mr Burbidge said.

"Since then, I don't know if there have been others, but I know of some reports from Victoria and south-east Queensland."

"It probably is the first sighting for a long time."

Genetic mutation can affect all birds

Experts are still trying to understand what makes some birds albino or completely black.

Mr Burbidge said their colouring was essentially the result of a genetic mutation.

Kookaburras can also be albino, like this one found in Queensland's far north in 2010, but it is rare. ( AAP )

"What we know is that some mutations in birds can upset the production of pigments and result in excessive production of melanin, which is the very dark pigment," he said.

Mr Burbidge said while most people were aware of albino birds, black ones were rarer but were not confined to kookaburras.

"Albino [birds] are about 20 times more common than black ones," he said.

"You get black birds from other species groups as well, not just kookaburras.

"Black birds have been recorded from a whole range of bird groups from pelicans to magpies and even some small song birds."