On-site surveys by the Department of Primary Industries conducted at Portland, Warrnambool, Port Fairy and Apollo Bay between March and July last year, found an estimated 19,700 tuna with a total weight of about 240 tonnes were caught and retained.

It was estimated another 6900 southern bluefin were also caught and released.

However, the true recreational catch is much higher because the study did not include dates from moored vessels, crews travelling by sea from South Australia or some larger boat trailers.

Figures from the recently-completed study, present a balance to concerns raised in The Standard on Saturday by environmentalist Penny Forth, who feared over-fishing was pushing the popular species to the edge of extinction.

Ms Forth, president of Warrnambool Environmental Action Group, said recreational fishers who were allowed four tuna a day per boat, could have a devastating effect on the “beautiful, sleek, jaguar of the sea”.

The survey calculated there had been an estimated 6200 boat trips by recreational anglers in Victoria for the prized tuna which have been luring hundreds of crews to the region on weekend expeditions.

Ninety-nine per cent of the anglers came from Victoria, 0.6 per cent from New South Wales and 0.4 per cent from South Australia.

According to the survey 90 per cent of the retained catch last year was landed in Portland, mostly between April and May and most of the fishing effort was over the continental shelf off Portland and Port Fairy.

Most of the released catch was by anglers interviewed at Warrnambool and Port Fairy.

They threw back 31 per cent of their catch while those interviewed at Portland released 25 per cent.

Reasons given for releasing catches included fears of exceeding the bag limit (79 per cent), unwanted fish (11 per cent) and fish considered too small (five per cent).

Portland has been enjoying a huge injection into its mid-year economy for the past few years and with Port Fairy and Warrnambool also sharing the boom to a lesser extent.

A proposed $6 million upgrade of Warrnambool’s breakwater harbour providing safer launching facilities would strengthen the city’s attraction for tuna hunters.

Warrnambool-based freelance fishing journalist and a member of the Victorian Recreational Fishing Grants Working Group, Marty Ellul, told The Standard the total southern bluefin tuna catch of recreational anglers represented just six per cent of Australia’s total allowable catch.

Commercial fishing accounts for 4015 tonnes.

He said the species is being caught off the coastline stretching from Port Lincoln in the west to Bermagui, NSW and further north and south to southern Tasmania.

“There are a lot more tuna about than was first estimated,” he said.

“Australian fisheries management, and in particular Victorian fisheries, are expertly run and are the envy of the world.”

According to the survey the lengths of tuna landed at Portland, Port Fairy and Warrnambool from March to July ranged from 63-163 centimetres with mean weights from 9-19 kilograms.

In Portland a total of 2846 boat trailers were counted during surveys over 81 interview days and 1405 interviews done with anglers.

At Port Fairy and Warrnambool combined, a total of 309 interviews were conducted over 57 days and 554 boat trailers counted.

The Apollo Bay interviews were recorded over 24 days with 210 anglers and 354 boat trailers counted.

Across all four ports anglers reported catching 4172 southern bluefin tuna.