Northern Territory anglers face new bag limits, while taking large barramundi and king threadfin is to be curtailed in some areas.

The changes, set to be released by the NT Government and backed by both amateur fishing enthusiasts and commercial operators, will ensure a limit is set per person of 15 fish, down from 30.

The personal possession limit for golden snapper will drop from five down to three, while the maximum size limit for barramundi and golden threadfin will be capped at 90cm for fish in the Daly or Mary River fish management zones.

Each vessel will however be allowed to have one barramundi or king threadfin over 90cms in length.

Species of fish historically not subjected to catch limits will have a default limit set at five per person.

Fisheries Minister Willem Westra van Holthe said the measures were essential to maintaining the NT's fishing spots into the future.

What you need to know about the new regulations General possession limit to be reduced from 30 fish down to 15 fish.

General possession limit to be reduced from 30 fish down to 15 fish. Personal possession limit for golden snapper reduced to three, from five

Personal possession limit for golden snapper reduced to three, from five Combined possession limit of 10 red snapper (all species), within the overall general possession limit of 15

Combined possession limit of 10 red snapper (all species), within the overall general possession limit of 15 Maximum 90cm size limit on barramundi and king threadfin taken in the Daly River or Mary River fish management zones.

Maximum 90cm size limit on barramundi and king threadfin taken in the Daly River or Mary River fish management zones. A vessel limit of one barramundi and one kind of threadfin over 90cms will apply to allow retention of fish that are unfit for release

A vessel limit of one barramundi and one kind of threadfin over 90cms will apply to allow retention of fish that are unfit for release Species not historically subject to species-specific limits will have a default limit of five per person.

Species not historically subject to species-specific limits will have a default limit of five per person. There will be a possession limit of five fish per species unless otherwise specified.

"We have realised for quite a number of years now that the fish stocks particularly around golden snapper and jewfish in the areas around Darwin have been depleted," Mr Westra van Holthe said.

"I expect that there will be some kickback from tour operators, some amateur fishermen might also as well."

But Amateur Fisherman's Association of the NT executive officer Craig Ingram supported the new proposals.

"We fully understand that these are difficult changes but the science is very clear that we need to reduce the harvest of golden snapper in particular by 50 per cent," Mr Ingram said.

"History is littered with fisheries that don't take the decisive action they need when the science shows that there are significant sustainability issues."

He said that over the years the size of the fish taken and the catch rates had been falling.

Chief executive of the NT Seafood Council, Katherine Winchester, said the new rules gave commercial operators certainty.

"Every sector to take responsibility for their catch levels is critical," Ms Winchester said.

"Today's announcement does give that security."