In a second incident, fishery officers stopped four Whangarei men on Sunday afternoon, allegedly carrying 474 toheroa shellfish, which had been taken from Ripiro beach on Dargaville's west coast, Mr Edwards said.
The ministry's website said toheroa must not be taken, possessed, or disturbed unless an open season is declared by MPI's director-general.
The men's vehicle was seized and it was likely they would also face charges of illegally taking toheroa in contravention of the Fisheries Act 1996.
Both offences carried a maximum penalty of a maximum fine of $250,000 and the forfeiture of any property or equipment used in the offending.
Mr Edwards said the rules were there for a reason, and those flouting them needed to be held to account.
"Toheroa are a prohibited shellfish, the only way that they can be gathered is by way of customary permit for hui or tangi. (Alleged) offending of this scale is nothing but blatant theft and undermines the Fisheries Act and further depletes a fishery which is already prohibited for this reason.
"While it's great that the vast majority of people stick to the rules and respect bag limits, there are always those who will try to get more than their fair share," Mr Edwards said.