A 66-year-old Russell man is facing prosecution after Fisheries officers say they caught him with a "massive" illegal haul of flounder and oysters.
Ministry for Primary Industries spokesman Steve Rudsdale said the scale of the alleged offending was disappointing.
The man had been caught with 97 flounder and 677 shucked oysters that were packed in punnets.
"The haul was commercial in scale. The man had more than three times the daily limit of both flounder and oysters," Mr Rudsdale said.
"On top of that, he was fishing with a net that was 178 metres long. The maximum legal length for a flounder net is 60 metres. The way the oysters were packed in punnets, and the length of the net, indicate that the illegal catch was destined for the commercial market.
"We'd like to remind people that they should always be motivated by collecting for a feed rather than greed, and that it's an offence to buy seafood from an unlicensed source," he added.
"Buying fish this way is also a food safety risk, particularly in respect of the oysters, given that commercial oyster farms in the Bay of Islands were closed recently due to high rainfall."
The man would face charges under the Fisheries Act, and his boat, nets and a vehicle had been seized.
Mr Rudsdale urged anyone who was unclear about the fishery rules, regulations and limits to go to www.mpi.govt.nz/travel-and-recreation/fishing/fishing-rules, or who witnessed or knew of suspicious fishing activity to call 0800 4 POACHER (0800 447-6224).