28 Jan 2018

Hot water boosts tiny tuna numbers

1:33 pm on 28 January 2018

Albacore tuna being caught near Westport are far more numerous, but "very, very small" compared to previous years, a fisherman says.

A fishing boat enters the Grey River after negotiating the notoriously dangerous crossing.

A fishing boat enters the Grey River. Photo: 123rf

Westport-based Nelson fisherman Michael Trounson said the fish he was catching were 2.8-3.2kg, about half the typical 5-7kg.

"Normally Talley's don't want the small ones, but there's a shortage in the market," he said.

Mr Trounson believed the warm water was the reason for higher numbers of juvenile fish being caught. There is no quota on tuna.

He has been fishing since he was 15, and said he was catching between 1.5 and two tonnes a day.

"I've caught in eight fishing days what I got for the whole season last year," he said.

"The number of tuna was a surprise and a good sign for the health of the fishing industry.

"I've been doing it since 1980, I've never seen this number of little ones."

He said the surface temperature plummeted past depths of 50m.

"There are big ones out there. When you get a spot of colder water, maybe just a square kilometre of colder water, you get the bigger ones - eight to 10 kilos.

"The reason why the bigger ones aren't appearing, they're down deep because the water temperature's hotter [higher up,] and they can't adjust their body temperature coming up."

Greymouth Port team leader Franco Horridge told the Greymouth Star there had already been more than last year's 20 extra boats in the harbour this year.

The fishermen were seeing a lot of larger fish on the sounders.

Mr Trounson said he thought more fish would come closer to the surface as they travelled south and into cooler sea, and most fishermen were doing likewise.

The tuna season does not normally get into swing until late January.

Westport-based fishermen at the wharf this morning said the number of boats using the port this tuna season was similar to previous years.

This story first appeared in the Westport News

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