A commercial fisherman has been fined $17,000 and had his boat seized for taking under-sized crabs.
During a search, the crabs were found hidden in a concealed compartment on the fisher's boat, according to Queensland Boating and Fisheries officers.
Two other commercial fishers have received penalties of $550 each for related record-keeping offences.
Capalaba MP Don Brown said $17,000 was a significant penalty and reflected how seriously the Queensland Boating and Fisheries Patrol pursued such matters.
"Acting on a tip off, in December 2018 QBFP officers searched a fishing boat at a Birkdale premises and found 146 under-sized blue swimmer crabs hidden in a concealed compartment," Mr Brown said.
"As part of the investigation, two other fishers were prosecuted for not completing sales dockets, not completing logbooks and selling fish without an authority.
"The Redlands QBFP, assisted by the Gold Coast team, conducted surveillance and gathered intelligence on the defendants before seizing the boat and then audited logbooks and sale dockets to establish a pattern of offending."
Fisheries Minister Mark Furner said three commercial fishers pleaded guilty to all charges in the Brisbane Magistrates Court, with convictions recorded for two of them.
"The main defendant who had his boat seized and fishing licence suspended, now has to pay a $17,000 fine plus court costs," Mr Furner said.
"This sort of deliberate targeting of under-sized crabs is in clear breach of our fishing regulations and is not tolerated.
The fact that they were hidden shows a premeditated disregard for the need to ensure sustainable stocks for other fishers.
"We are building a legacy of a sustainable fishery for our children and grandchildren."