Supporters of a new 95-metre factory fishing trawler are calling for calm as opposition to the SeaFish Tasmania vessel ramps up.

Three years ago recreational fishermen and conservationists took to the water to protest against the company's super trawler, the Margiris.

It led to a Federal Government ban on super trawlers longer than 130 metres.

SeaFish Tasmania's new vessel, the Geelong Star, is 35 metres shorter than that and is already fishing off the Great Australian Bight.

Recreational fisher Tyson Clements said the community would not stand for it and was preparing to fight.

"We are going to stand up as one, in all different parties and groups, and we are going to stop this thing," he said.

"We do not want it here, now or ever."

The Geelong Star is permitted to catch 16,500 tonnes of red bait, jack mackerel and sardines - 7.5 per cent of the total allowable catch for the small pelagic fishery.

Grahame Turk from the Small Pelagic Industry Association said the Geelong Star was not a super trawler.

"It's not a monster boat, its not a super trawler, it's a medium-sized, mid-water freezer trawler boat."

He said although the vessel had an 80-metre wide net it was no bigger than previous vessels that fished the same waters.

Mr Turk was in Tasmania to quell concerns ahead of planned rallies.

"The photos of the boat that are being used in the advertisements are even the wrong boat," he said.

"There's an enormous amount of misinformation driving this rally."

Professor Colin Buxton, leader of Small Pelagic Research Group, agreed.

"It frustrates me that people haven't gone past where they were the first time round," he said.

"I mean, a lot has been done in the past two years."

Fishery not in danger, research group says

Professor Buxton has reassessed fish stocks and found they were far greater than earlier predictions.

"We can tell you now with some confidence that there's well over 150,000 tonnes of mackerel out there, which makes us feel really good about our first estimate of 130,000 tonnes," he said.

But Mr Clements said the trawler being smaller than the Margiris did not allay fears of overfishing.

"As far as we're concerned, all the same issues are here - the localised depletion of the stocks of our bait fish off the coast of Tasmania," he said.

Sorry, this video has expired Fresh battle over factory trawlers ( Annah Fromberg )

The Geelong Star will fish three nautical miles out to sea in waters around southern Australia, from Perth to northern New South Wales.

Mr Clements said the vessel was able to catch the same quantity of fish in the same timeframe as the Margiris.

"We still feel that the capacity of this ship is far too great for the fishery, and we do not trust the science," he said.

"The science is a drop in the ocean. There's not enough money being put into this because this fishery is not worth a great deal."

Professor Buxton disagreed and urged members of the community to familiarise themselves with the latest research.

"My message is that people should make themselves informed," he said.

"People should read and get better information than they had last time around."