Game bird hunters are being advised to take the opportunity that the shortest day offers for maximise their hunting opportunities.

With there being less than nine hours of daylight on June 21, hunters can pack in a lot of hunting as the ducks head back to the waterways to camp up.

Typically, ducks will leave on dusk to raid farmland crops during the night, before returning back to river and lakes early in the morning, says Fish and Game New Zealand.

"With this in mind Fish and Game are promoting the "shortest day hunt" in an effort to get as many hunters out as possible.

"Hunters can take advantage of this day, simply by getting back out to their maimai's, with the expectation that the ducks won't be sitting on a vacant pond down the road, as hunters will be there too."

All hunters need to do is go hunting on the shortest day, in the morning or evening, or both, and encourage all their game bird licence holder mates to do the same.

Fish and Game says this is a "great opportunity to take the kids out for a hunt, or even introduce someone new to the sport as day licences are only $23".

"It has long been realised, that the more hunters out there, the better everyone will do.

"Hunters are reminded that 2019 maimai claim tags only remain current until the 2021 pegging day if the hunter has purchased a 2020 game bird licence.

"Hunters looking to claim maimai's that are possibly unused, need to contact Fish and Game, to find out if the name on the tag is a current 2020 game bird licence holder."

The mallard season has a couple of weekends to go in most North Island regions and runs until July 26 in the South Island.

"We advise that duck numbers are very good throughout the country."