The future of Scotland's fishing industry dominated first minister's questions at Holyrood.
Scottish Conservative leader Ruth Davidson accused Nicola Sturgeon and SNP MPs of inconsistency on the EU's Common Fisheries Policy.
Ms Sturgeon said that Ms Davidson was "flip-flopping" on Brexit like a "landed fish" and the Tories were preparing to "sell out" the fishermen.
The dominant view of the fishing industry is for leaving the EU.
The European Union's Common Fisheries Policy (CFP) sets quotas for fishing catches and seeks to give all European fleets equal access to fishing grounds.
Ms Davidson said SNP MPs such as Angus Robertson had claimed that if Scotland were to vote for independence then it would re-enter the EU and the "hated" CFP.
However, SNP MPs in fishing communities, including Banff and Buchan's Eilidh Whiteford, have signed a pledge to support the UK regaining control of its coastal waters after the country quits the European Union and the CFP.
The Tory leader said the SNP's positions were "absurd".
The first minister said the SNP had been consistent over many years in its criticisms of the Common Fisheries Policy, saying it should be "fundamentally reformed".
Ms Sturgeon said the White Paper for 2014's Independence referendum said it would give Scotland the opportunity to take a lead role in reforming the CFP.
She said: "The uncomfortable truth for Ruth Davidson is that it is successive Tory governments who have sold out the fishing industry."
Ms Sturgeon referred to an internal Scottish Office memo from 1970, when negotiations on entering the EU were being conducted by the then Conservative UK government.
It said: "In the wider UK context, they [the fishermen] must be regarded as expendable."
The first minister said: "We know the Tories are lining up to sell out fishing again because the Brexit White Paper makes it clear that fishing will just be a negotiating chip in the Brexit talks."
She referred to a line in the Brexit White Paper that says the UK government wants a deal that works for Scotland's and the EU's fishing communities.
Ms Sturgeon claimed that Ruth Davidson, who was against Brexit in the run-up to the EU referendum, had fallen into line with Prime Minister Theresa May and now "Brexit was the greatest thing since sliced bread".
Ms Davidson said the Scottish government's Brexit minister Mike Russell had said that after independence Scotland would go back into EU but not the CFP.
She told the chamber "This is utter nonsense.
"Right now we have SNP MPs in fishing communities saying the CFP is terrible and Scotland would pull out - and at the same time we have Nicola Sturgeon standing up in Edinburgh trying to win the vote of Remainers, saying they would go straight back in."