Fishing fleets could net millions in extra income thanks to a revival in stocks of key species, the European Commission (EC) has said.
Twenty fish stocks in European Union (EU) waters are now considered to be within sustainable fishing limits, compared with only five in 2009, said fisheries commissioner Maria Damanaki.
The figures are rare good news after years in which fishermen have faced massive catch reductions in the name of conservation and on the promise of plenty in the future.
The EC has blamed successive years of enforced cuts on fleets routinely breaching catch quotas and delaying stock recovery.
However, ahead of EU fisheries reform talks next week, Mrs Damanaki declared: "We are now seeing some improvements towards ending overfishing, but we need to go the extra mile and adopt Common Fisheries Policy (CFP) reform if we want to guarantee these improvements in the long term."
A commission "consultation document" looking at fishing opportunities for next year says efforts to halt overfishing are starting to work, thanks to reduced annual catch quotas in recent years.
The effectiveness of quota cuts allowed increases in the total allowable catch (TAC) for some stocks this year, says the report - with an estimated extra income for the fishing industry of 135 million euro (£109 million).
An EC statement said: "The figures show that following scientific advice when setting TACs helps fish stocks rebuild. As a result, fishermen are rewarded with higher catches and higher income, and the environmental impact of fishing is less."
The upbeat note came as lobby groups mounted a campaign against what they see as compromise proposals on EU fishing policy. Birdlife Europe, Greenpeace, OCEAN2012, Oceana, Seas At Risk and WWF issued a joint statement warning that a proposed deal would not stop the depletion of fish stocks for another decade.
They said fisheries ministers were preparing to settle for a "lowest common denominator" deal "without any ambition to achieve sustainable fisheries or save fishing jobs".