Marlborough fishermen have lobbied minister David Carter to change the Marlborough Sounds blue cod rules.
But he says nothing will happen before a "major" assessment in 2014.
Marlborough Recreational Fishers' Association acting chairman Tony Orman, executive member Laurie Stevenson and researcher John Leader met the Primary Industries Minister at the Beehive on September 26 to discuss the fishing rules.
The association recommended the slot rule be replaced with a 33-centimetre size limit, that all cod fishing be closed in August and September, and that the transit rule be abolished.
The slot rule means all fish smaller than 30cm and larger than 35cm have to be thrown back,
The changes are wanted because of a disagreement with the ministry over when fish mature and breed.
Mr Carter said many fishermen needed to be better educated on how to catch and throw back blue cod that fell outside the 30 to 35cm slot rule to lower the fatality rate.
"All agreed there was a job to do there . . . to maximise the opportunity for those to be survivors," Mr Carter said.
Using larger hooks would help stop the fish from swallowing it and gently putting them in water on the boat would help reduce the chances they died.
"I said, I had to be advised by the science presented to me as minister.
"I was accepting of the advice that the ones being returned were potential breeders."
Mr Orman disagreed with the rule and said that blue cod began spawning at 20-22cm in length and tended to change gender to male within the slot range.
"In essence, the slot rule is forcing anglers to kill the larger breeding female fish," Mr Orman said.
He believed the science presented to the minister was incorrect and that the closure period, from August 31 to December 20, would better cover the fish's breeding period if it was in August and September.
Mr Carter said he was aware some fishermen disagreed over what the size and closure rules should be.
As an example, he said there was a "difference of opinion" between the three delegates at the meeting.
The minister explained that the transit rule, which limits Marlborough fishermen to having only two blue cod in their possession even if they were fishing outside the Sounds, was the easiest way to protect blue cod numbers.
Evidence of where fish were caught was often difficult to provide and monitor, he said.
"It's solely for getting good enforcement of the regulations and I think they accepted that," Mr Carter said.
The ministry will conduct a "major" stock assessment of blue cod numbers and sizes in the Marlborough Sounds in 2014.
There would be no review of the rules until the results of it were out, possibly in 2015, he said.
A Primary Industries Ministry spokesman said the results from a Niwa study in 2010 on blue cod size and numbers in the Marlborough Sounds would be released next week.
The delayed publication was due to the replacement of a key investigator at Niwa.
The work was originally reported to the Southern Inshore Working Group in October 2011, who suggested additional analysis before the ministry accepted the report.
The present rules were based on a survey conducted by Niwa in 2007.
Mr Leader felt the minister was attentive through the meeting and the group got across the "strong frustration" of some recreational anglers.
- The Marlborough Express