Anglers are being given the chance to reel in the catch of their career - a $1 million snapper.
Fifty snapper will be tagged and released into the Hauraki Gulf as part of a 10-day fishing contest in April. Each fish will be worth a prize, including one of $1m.
Million Dollar Snapper Challenge organiser Dave Baty expected at least 3,000 recreational fishers to take part in the event.
But you'll beat long odds if you catch the fish. University of Auckland statistician Associate Professor David Scott estimated if an angler caught three fish there was a one in eight million chance of catching the million-dollar snapper.
Baty, who runs Prestige Events, said in similar contests overseas, about 10 per cent of tagged fish had been caught.
"There are territorial snapper which might not go far from where they're released, but there are also school snapper which could end up quite a distance away."
Niwa staff will catch, tag and release the snapper from around the gulf.
The $1m first prize will be paid in annual instalments of $50,000. Among the additional $250,000 in prizes is an Isuzu D-Max ute and a Fryan/Honda marine boat package.
Competition organisers are keen to promote catch-and-release fishing, with tagged fish not needing to be killed for the prizes to be claimed. They will also use a smartphone app that can measure a fish and participants will be given a "lip hook" jig, which does minimal damage to fish, and a cloth to help fishes' chances of survival. The April fishing contest is also fundraising for Cure Kids, Coastguard and Blue Light.