DOC Renwick compliance officer and backcountry ranger Ray Bennett and his dog Tui will be patrolling Marlborough waterways as whitebait season kicks off on Tuesday.

Whitebait fritters could be off the menu for good unless depleted populations are allowed to recover, activists warn.

Numbers of New Zealand's best-loved seafood snack have been in steep decline, and activists say whitebaiting season, which starts on Tuesday, should be banned for a year.

Whitebaiters argue the ban would be "bloody pointless" and that critics are citing flawed research.

Council of Outdoor Recreation Association co-chairman Bill Benfield believes the fishery needed time to recover in its own, natural way.

READ MORE:

* Whitebaiters ready to battle for best spot

* Boundaries set for Marlborough whitebait season

* Outdoor group wants ban on commercial whitebaiting

​* Is it time to ban commercial whitebaiting?

"This can't continue much longer. I think the fishery should be closed, full stop," he said.

SCOTT HAMMOND/STUFF Whitebait, fresh out of the water.

"It's had it, it's been screwed. It is unsustainable for both recreational and commercial."

Benfield said he understood whitebaiting was a Kiwi tradition, but argued fishers were contributing to the decline and eventual decimation of the fishery.

"We're loving it to death," he said.

STUFF A man checks his net at the Wairau Diversion in Marlborough during whitebait season last year.

But the Department of Conservation (DOC) isn't certain fishermen are to blame, saying habitat loss is a key factor driving the threat status of whitebait.

Marlborough Recreational Fishing Association life-member Tony Orman did not agree that whitebaiting should be completely banned, but said something had to be done to restore population numbers.

There were plenty of whitebait sellers who popped up during the season in Marlborough and some were catching as much as possible to turn a profit, Orman said.

STUFF A whitebait pattie is one of the most popular ways to cook the fish.

"They are wrecking the resource," he said.

"It is prostitution of a recreational activity, I believe it should solely be a recreational pursuit.

"Do we wait to see whitebait just go down and down and down? The first step must to be to get rid of the commercialism and where we can, restore the habitat and stop the destruction of habitat."

SCOTT HAMMOND/STUFF Whitebaiting at Wairau Diversion on the first day of the season last year.

The five main species of whitebait include inanga, koaro, banded kokopu, giant kokopu, and shortjaw kokopu. ​Whitebait catches sometimes included smelt, bullies and juvenile eels.

Based on the population of adults, whitebait was in decline. According to the DOC website, the shortjaw kokopu was "threatened" while three species—inanga, koaro and giant kokopu—were in "decline".

West Coast Whitebaiters Association president Des McEnaney said people calling for a ban relied on hearsay and flawed research.

There were still many unknowns in the science around whitebait and a knee-jerk ban would not achieve anything, McEnaney said.

"It would be bloody pointless. The effect would be so minimal it would be a waste of time," he said.

"A ban would create disharmony across the whitebaiting community for no advantage whatsoever. Fishing is a small part of the bigger picture."

The West Coast had its own rules compared to the rest of the country, with their season set to run from 1 September to 14 November.

DOC Renwick compliance officer and backcountry ranger Ray Bennett had whitebaited in Marlborough rivers for 45 years.

DOC would be out in force to ensure people were following the rules and enjoying the season, he said.

"I'm there to police the law as it stands, all I have to worry about is it being done legally," he said. "I'm not anti-whitebaiting, I'm anti people whitebaiting illegally.

"It's funny how such a small fish can bring out the best and worst in people on the river."

Bennett said the vast majority of whitebaiters followed the rules, such as using one net at a time, staying within 10 metres of their net and making sure it did not exceed more than a third of the water channel's width.

Illegal whitebaiting carried a maximum fine of $5000 and fishing equipment could be seized.