Fishing fleets face fewer days at sea but bigger catch quotas after marathon talks which ended at dawn in Brussels.
UK Fisheries Minister Richard Benyon said he had secured "the best possible deal" for the fishing industry after three weeks of behind the scenes negotiations and two days around the negotiating table.
Britain fended off moves to cut fishermen's days at sea to just four a fortnight next year, in exchange for greater national fish conservation efforts.
But boats will still be confined to ports for longer than before - making it tougher to capitalise on some big rises in fish catch quotas which reflect that conservation is working in some regions.
Mr Benyon said: "After two days of tense and frustrating negotiations I am delighted to have secured the best deal possible for the UK fishing industry and ensure the future sustainability of our fish stocks.
"By arguing that we should follow scientific advice we have been able to agree quotas that will not only allow local fishermen to make a living but will also ensure that we can protect the environment.
"One of my primary goals was to see off the threat of excessive reductions in days at sea which would have put key UK fisheries at risk."
His Scottish counterpart, Fishing Secretary Richard Lochhead, said: "These have been the toughest of negotiations that have delivered both significant gains but also huge frustrations.
"Scotland's fishing industry has endured three weeks of anxiety following Europe's initial decision to cut the fleet's time at sea and prevent it from catching our quotas. Now that particular threat has been lifted as a result of talks in Brussels and our fishing communities can breathe a sigh of relief."
Mr Lochhead added: "Quotas are the lifeblood of the fleet and we have won increases for our key stocks in line with the science. There is very good news on the west coast in particular with a 200 per cent increase in haddock quota and the removal of regulations that were hurting the fleet."
Other major increases in catch allowances for 2012 are a doubling of the north-east coast herring quota and a 150 per cent rise in south-west cod catches.
Smaller rises include 25 per cent bigger catches for south-west haddock, and 15 per cent increases each for north -east haddock and north-east and south-west whiting, and a 9 per cent rise in Channel sole catches.
The retention of this year's Northern Irish scampi catch allowance will help protect the region's fishing industry in 2012, said Mr Benyon.
He also argued successfully for the continuation of existing quota levels for whitefish stocks in areas where the European Commission proposed 25 per cent reductions.
But an overall cut in days at sea will still hit hard-pressed fleets, particularly in designated cod recovery zones under the Commission's Cod Recovery Plan, where efforts to revive depleted stocks have only partially succeeded so far.
Mr Lochhead said: "We are very disappointed that despite the call from many member states for a pause in the annual cut in days at sea for vessels that fish in the Cod Recovery Zone, Europe pressed ahead."
He insisted: "There are other ways to protect cod stocks than keeping the fleet in port and we will work with those vessels affected to ensure they remain viable. Our Conservation Credit Scheme can allow affected vessels to top up their days at sea by adopting cod avoidance measures.
"It is also very disappointing the Common Fisheries Policy has yet again delivered such a chaotic and confusing set of negotiations.
"The Commission themselves have admitted that the CFP including the Cod Recovery Plan isn't working with the lawyers running the show to the detriment of conservation and the fishing industry. Next year's reform of the CFP cannot arrive soon enough."
One welcome reversal was a Commission decision to drop plans to impose penalties on vessels exceeding four days at sea per fortnight - a decision which the Scottish government days avoids the "decimation" of the Scottish fleet at a cost of £160m to the economy.
Bertie Armstrong, chief executive of the Scottish Fishermen's Federation, hit out at cuts in days at sea estimated at between 15 per cent and 25 per cent, saying: "While fishing opportunity in terms of tonnage has always been vital, this time around it was the granting of enough time at sea to actually catch the fish that was under threat.
"This is a bitter blow for our fishing fleet, which is now going to struggle to maintain economic viability under the impact of these totally unwarranted cuts.
"Effort control(by cutting days at sea) is fundamentally flawed as a fisheries management measure and the Commission has totally ignored the real progress in stock conservation in Scotland in recent years through unilateral conservation measures that have helped boost stock recovery. Our whole industry is now facing a very difficult future."