European governments are backsliding on commitments to make fishing sustainable, campaigners are warning.
Talks on Common Fisheries Policy (CFP) reform are seeing important changes in moves to eliminate discards, reduce fishing fleets and rebuild fish stocks.
The original aim of repopulating stocks by 2015 is facing a five-year delay.
About three-quarters of European stocks are overfished, and studies show fishermen would have a more prosperous future by curbing catches now.
The main battle line pits more conservation-minded northern countries such as Germany and Sweden against southern states keener to protect fishermen's' short-term interests, including Spain, Portugal and France.
"The question is very basic - do EU fisheries ministers have the courage to end overfishing or not?" said Markus Knigge, advisor to the Pew Environment Group.
The original CFP reform proposal put forward by European Fisheries Commissioner Maria Damanaki last year contained three key elements:
- restore all fish stocks to maximum sustainable yield (MSY) by 2015
- reduce and regulate the size of the EU's fishing fleet through an internal trading mechanism
- eliminate the wasteful practice of discarding fish that are outside a boat's quota.
Governments have been negotiating on Ms Damanaki's proposal ever since, with the aim of finalising a package by next year.
The trading mechanism, known as Individual Transferable Quotas, saw considerable opposition and will almost certainly not happen.
Instead, each member state will take responsibility for managing the size of its own fleet. The final agreement is likely to include a mechanism for sanctioning countries that do not make adequate arrangements.
This is raising alarm bells with some environment groups, who point out that many EU nations have proven unwilling to manage their fleets in the past.
Agreeing decentralised, regional management was a priority for the UK, which has successfully reduced capacity in its own fleets.
Campaigners were alarmed by rumours of a backroom deal under which France would support the UK on decentralisation if the UK backed French moves to water down the discard ban.
But Richard Benyon, the UK Fisheries Minister, said that was not the case.
"We have asked France to join with us in our proposal on regionalisation - it's been adopted by Scandinavian and other northern European states and we want France to be part of it too," he told BBC News.
"They did canvas opinion about a proposal that would have watered down the discards policy, and we said we wouldn't be part of that."
However, Mr Benyon said there were complexities with achieving a complete discard ban that were not always appreciated by campaigners.
This is especially true in areas such as the North Sea, where a number of fish species live together and boats cannot altogether avoid catching ones they are not targeting.
"There are certain pelagic stocks where we can have a discard ban tomorrow, and there are mixed fisheries where more detailed work is needed," he said.
This "detailed work" is a combination of selective fishing equipment, smart regulations on issues such as fishing areas and times at sea, and a financial package that allows caught fish to be utilised without giving skippers an incentive to catch outside their quota.
But Mr Benyon said a complete discard ban would be achieved in UK waters in "a very short period of time".
He also said the UK supported the inclusion of an aim to ban discards in the CFP's basic rules.
Some countries have been arguing that discard regulations should be delegated to long-term "recovery plans" covering individual species or locations. Environment groups argue this would entail a major watering down of the headline commitment.
The issue arousing most concern is slippage in the commitment to rebuild stocks to maximum sustainable yield (MSY) by 2015.
Maximum sustainable yield is a target for the size of a stock. It is the level that gives fishermen the biggest annual catch they can have without depleting the stock.
Under the latest draft negotiating text, governments would "aim to ensure that exploitation of living marine biological resources" rebuilds stocks to MSY "by 2015, for all stocks where possible, and by 2020 at the latest".
In 2002, all governments of the world pledged to restore stocks to MSY "with the aim of achieving these goals for depleted stocks on an urgent basis and where possible not later than 2015".
European ministers are arguing that the words "where possible" mean they are entitled to water down the 2015 commitment.
However, environment groups argue that the words were included only to allow poorer developing nations time to gather the data needed to set an MSY target.
In addition, some EU governments are arguing that they should target a different measure, known as FMSY.
This is the amount of catch that could be taken sustainably if stocks were at MSY levels. But some ministers argue their fishermen should be allowed to catch at FMSY rates even on stocks that have not been replenished, and that this constitutes sustainable management.
Next month the Danish government hosts a key session of environment ministers at which it plans to secure a show-of-hands agreement on major elements of the package.
The European Commission says ministers must preserve pillars of the original proposal if they want to bring meaningful change.
"We need firm dates for MSY, and we need a firm and effective discard ban as part of the basic rules," said Ms Damanaki.
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