Fur seal frolicks with visitors in a lake after swimming kilometres inland

Nicole Mathewson Reporter from The Press

From reporter Joanne Naish:

A fur seal has been making himself at home and putting on a show for visitors in a West Coast lake.

Lake Moeraki Wilderness Lodge owner and guide Gerry McSweeney said New Zealand fur seals had been visiting Lake Moeraki for the last five years. Lake Moeraki is 3km upriver from the Tasman Sea in South Westland, north of Haast.

A male fur seal has been resident in the lake for the past six months.

“They seem happy here and eat a regular diet of eels and trout. We see this particular male almost every day over a stretch of about 5km of river and lake,” he said.

McSweeney takes tourists out on kayak trips on the lake, which is surrounded by rainforest and the Te Wāhipounamu World Heritage Site.

The fur seal recently frolicked in the water lying on his back and waving his flippers around near a group of kayakers.

“Their behaviour lying on their backs and waving their flippers about in the sunshine is to do with thermoregulation. They do this in sunny weather and keep warm from the sun on their flippers,” he said.

He believed the fur seals were attracted by a plentiful food source, but their presence had not dented the trout population in the lake, he said.

“The trout fishing in Lake Moeraki remains very good. This is further evidence that the presence of a large predator actually helps improve the health of the prey population because the predator will generally only eat the old, the sick and the weak species leading to an overall improvement in the health of the prey population,” he said.

McSweeney said it was unusual to see seals in freshwater. He only knew of Lake McKerrow in the Lower Hollyford Valley in northern Fiordland as the other place where fur seals have been seen in a freshwater lake.

“This is not common anywhere in New Zealand. Our visitors think the presence of a seal in Lake Moeraki is yet further evidence of what a special place the West Coast is,” he said.

Department of Conservation’s West Coast Marine Reserves Ranger Don Neale said it was an interesting find.

“It’s interesting and uncommon, but not unheard of to have a seal in such a lake. Lake Moeraki is a pretty easy swim upriver for a seal,” he said.

Fur seals had previously been seen up to 20km up rivers in other parts of New Zealand.

“We call them marine mammals, but they don’t know that,” he said.