Angling groups are calling for fishing restrictions to ease pressure on country river systems and fish stocks.

The fishing enthusiasts want a roster introduced to restrict Kiwi and international anglers from hitting the water on the same day.

The Federation of Fresh Water Anglers says an increase in anglers from overseas is having a dire impact on salmon and trout populations.

It's also causing pollution problems for many rivers in the North Island.

Federation President Graham Carter is suggesting a rostered system shared between Kiwi and international anglers, with days when no one would be allowed to fish.

"For example, Tuesday, Wednesday, Thursday for non-resident anglers on some rivers, and then the Friday, Saturday, Sunday for resident Kiwi anglers.

"Monday could then be a rest day for the river."

"You have rivers like the Tongariro, that can handle 100 anglers on any day and it has no effect.

"But when you get a little river like the Greenstone that you can pretty much jump across, little rivers like that just can't handle that sort of pressure."

The Greenstone River is at Lake Wakatipu.