"This is despite Department staff going to great lengths to erect large signs in many different places around the Reserve to alert the public of the rules and regulations that govern its use."
Ms Norgate said in some cases, the alleged offenders would have passed up to seven signs on their way into the Reserve.
"At least one was parked directly in front of a sign," she said.
"All of the alleged offending has been carried out in full view of the large one metre by three metre bright orange triangles which mark the boundaries of the Reserve."
Ms Norgate said those caught may be prosecuted under the Marine Reserves Act.
Under the Act, penalties for taking marine life from a marine reserve include up to three months in prison, fines of up to $10,000 and possible forfeiture of boats and fishing equipment.
"Marine reserves are fully protected areas.
"They allow the ecosystems within them to return to near their former glory, and sustaining a variety of sea life. This can also support an increase in local fish stocks." Te Angiangi Marine Reserve spans 446 hectares and was created in 1997.
If you spot suspicious activity in a marine reserve, including taking of fish or shellfish, should call the 24-hour DOC emergency hotline 0800 DOC HOT (0800 362 468).