BURKE the Koala has every right to be looking pleased with himself.

He has just arrived at Longleat Safari Park in Wiltshire to help its breeding programme.

Longleat, near Warminster, has the only two male southern koalas outside of Australia after a newcomer arrived from Japan.

Twelve-year-old Burke has been flown from Osaka to the Wiltshire park to help boost its breeding programme for the threatened marsupials.

Koala numbers are decreasing rapidly due to disease and habitat loss.

It has been estimated there are fewer than 100,000 koalas in their native Australia.

After spending time in the koala care room, Burke will join the other male, Dennis, and females Maizie, Violet and Coorong in the purpose-built display.

"We're delighted to have another male join our existing group and he seems to be settling in really well to his new surroundings," said Longleat's Graeme Dick.

"He was originally born at Melbourne Zoo back in 2006 where he was named Burke, although in Japan he was known as 'Ark'.

"His arrival is a major boost for our breeding programme as he will provide us with a greater genetic diversity.

"We have already seen early signs of courtship and breeding behaviours between the females and Dennis so we're all cautiously optimistic we could have some positive news in the not too distant future."

A female called Wilpena, died earlier this year as a result of the kidney disease oxalate nephrosis.

Up to a third of southern koalas suffer from a form of kidney disease, while northern koalas numbers have been hit by cancers and a form of HIV.

Scientists studying the Longleat koalas believe they have identified a genetic mutation and a retrovirus present in the southern koala population.