When you think of koalas, you would probably picture them in a gumtree munching on leaves, but one lucky north Queensland family captured this animal indulging in some rarely seen beach behaviour.

Professor Krockenberger says there have been a number of observations of Magnetic Island koalas showing an inquisitive nature. "They have come down from trees close to the rocks where people are fishing, had a bit of a look at them and then wandered off up to another tree. So it is clearly within their behavioural repertoire to indulge in this sort of activity every now and then, but every time it does happen people are quite surprised by it," he said. (ABC North Qld: Jamie Rule)

"Any time that a koala is not in a gumtree eating leaves people think it needs to be rescued, because it is somehow in trouble. They are interested, they see something a little bit different and they go to have a look," he said. (ABC North Qld: Jamie Rule)

James Cook University's Professor Andrew Krockenberger says while it is a rare sight to see a koala on the beach, it is not unheard of. "It is not normal, we don't see that very often, however it is not so abnormal that I've never heard of this before. Koalas found in islands of the Noosa River are known to even swim between islands," he said. (ABC North Qld: Jamie Rule)

ABC North Queensland's Jamie Rule was on holiday with his family on Magnetic Island when a koala climbed down from a tree and went for a wander on the beach.

Watch the video of the koala encounter here.

James Cook University's Professor Andrew Krockenberger and his team of researchers have been studying Magnetic Island's koala population for the past six years.

They estimate there are over 600 koalas on the island and that they are a healthy population.

Professor Krockenberger says koalas were not on the island when Europeans first navigated north Queensland.

"Koalas were moved around extensively throughout Queensland and New South Wales and Victoria and koalas were brought onto Magnetic Island during the 20th century," he said.

"In around the 1920s and 1930s there was a lot of concern about koalas and there was a bit of an Australia-wide push to conserve koalas.

"People also started to make little sanctuaries for them and bring them to different islands and Magnetic Island was one of those islands.

"They were probably translocated from somewhere close by on the mainland, possibly as far south as Mackay."

He says what makes the Magnetic Island population most fascinating is that they are more stable than similar island populations elsewhere in Australia.

"Their population is without the boom and bust cycles that we see on southern islands," he said.

"We are trying to understand what the population dynamics are like and why they don't build up like the southern koalas.

"We have been looking at the nutrient quality of foliage as well as some other issues, but we don't have an obvious answer yet."