Fisheries officers also seized more than 100 fish, sharks and sea snails during the operation, which focused on illegal fishing in the Batemans Marine Park between December 27 and January 12.

Officers were kept busy, issuing cautions for fishing in sanctuary zones, fishing with bait in the Montague Island habitat protection zone and fishing without paying fees.

Cautions were also written up for fishermen caught with prohibited size lobsters, abalone, yellowtail kingfish and flathead, along with people taking more than the legal bag limit.

Prohibited-size eastern rock lobsters, abalone, six large gummy sharks (taken from a sanctuary zone), 621 turban snails and 250 sea urchins, were also seized.

DPI acting compliance director Tony Andrews said it was disappointing that some fishers were still doing the wrong thing.

"During the operation, a umber of persons found fishing in ... sanctuary zones were local residents or anglers who were regular visitors to the area and had knowledge of the [marine park]," he said.

"Recreational and commercial fishers are required to be aware of any fishing restrictions relating to where they choose to fish.

"Ignorance of the fishing rules, especially those relating to the marine estate, is not an excuse ..."

Some illegal fishers are now facing heavy penalties, including hefty fines and possible jail time.

Anyone wanting to report illegal or suspicious fishing activity should call the Fishers Watch Phoneline on 1800 043 536.