Pacific seastar found in Gippsland Lakes

TWO Northern Pacific Seastars have been found in the Gippsland Lakes, prompting the Department of Environment Land Water and Planning to establish an incident management team to investigate the location and extent of the population.

DELWP incident controller Ben Rankin said the Northern Pacific Seastar was an exotic marine pest that had the potential to eat native marine creatures.

“In particular, this seastar can consume native shellfish which are an important part of the food chain,” he said.

“There is an established population of this pest in Port Phillip Bay where it has done considerable damage.”

The seastars have also been directly implicated in the decline of the endangered spotted handfish (Brachionichthys hirsutus) in Tasmania.

It is thought the voracious predators prey on handfish egg masses and the sea squirts (ascidians) that handfish use to spawn on.

They can also pose a threat to commercial shellfish farming and have affected oyster production on some marine farms in south-eastern Tasmania.

Worryingly, the Northern Pacific Seastar can rapidly establish large populations in new areas.

Estimates indicated the population had reached 12 million two years after they were first detected in Port Phillip Bay.

Tens of thousands of seastars have been removed in eradication attempts, but with little effect on overall population numbers.

The Northern Pacific Seastar is established at Tasmania’s Derwent River Estuary and east coast and Port Phillip Bay in Victoria, and was probably introduced into Australia through ballast water from Japan.

It was first confirmed in the Derwent River in Tasmania in 1992 and in Victoria in August 1995.

The Northern Pacific Seastar is a species native to the coasts of China, Korea, Russia and Japan, and they are also found across the Bering Sea in Alaska and northern Canada.

It was detected in the Gippsland Lakes by Friends of Beware Reef Marine Sanctuary divers Alan and Michael Wilkins.

This volunteer group regularly dives to survey, photograph and monitor reefs.