Conservationists are welcoming more transparency from one of the country's largest fishery companies.

The fishing company has offered to end its commercial fishing in the gulf if other fishers record and report their catch.

Sanford believes there is no accurate measure of fish stocks, because at least half of fishing in the gulf goes unreported.

Forest and Bird advocate Katrina Goddard believes the extra information will be helpful.

She said it will show where fishing is causing harm, and where it's OK.

"There might be some methods of harvesting certain types of seafood that is actually not having widespread ecological effects."

Goddard said the company has hit the nail on the head with its announcement.

"What we are seeing is localised depletions of certain species - in some areas its almost impossible to find crayfish."

Katrina Goddard said extra information could help prevent depletion of stocks.