Eight people have been charged under the Fisheries Act for taking crayfish to sell without a permit after a Ministry of Primary Industries (MPI) sting.
The accused will appear in the Kaikoura District Court on Friday.
An MPI spokesman said several others were also likely to be charged in relation to the 12-month operation.
An undercover officer from MPI bought 1200 cooked crayfish from recreational fishermen during "Op 15".
Fairfax understands some were bought out of people's freezers at private properties and after deals were made at pubs.
An anonymous source said a lot of people in Kaikoura knew what was going on, but it was not "the average civilian's" job to do anything about it.
Under the Fisheries Act, catching and illegally selling crayfish is punishable by up to five years' imprisonment and a $250,000 fine.
MPI seized 10 cars, five boats and a tractor when they searched 32 properties and more than 40 people were caught.
Compliance director Dean Baigent said there had been a "thriving" black market in Kaikoura for some time.
Recreational black-marketers were selling whole cooked rock crayfish for between $10 and $15 each, he said.
CRAMAC5 spokesman Larnce Wichman said he was relieved no commercial operators, iwi members or charter operator had been implicated.
Wichman, who is also chairman of coastal guardian group Te Korowai o Te Tai o Marokura, said the arrests were "divisive" in the Kaikoura community, however opinions were "weighed definitely against [black market activity] rather than for".
"It is going to be interesting to get the names out. They have been operating for some time - below the radar. The sad thing is there appears to be more problems when there is an abundant fishery.
"[Poachers] can get it so easily and so quickly, but how long can a fishery or resource sustain that?" he said.
"This type of behaviour cannot be tolerated."
Te Korowai secretary Gina Solomon, of Ngai Tahu and Ngati Kuri descent, said seafood black-marketing had been going on for several years, which was one of the reasons the coastal guardian group had been set up.
"I do not know who the people are, [but] it is disappointing that this has been going on," she said. Fairfax NZ
- The Marlborough Express
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