One of the nation's favourite dishes could have had its chips unless more is done to halt global warming.
Scientists say that cod and haddock could become extinct because rising temperatures are cutting oxygen levels in the ocean.
Marine zoologist Prof John Spicer said it was a “major cause for concern”.
He added: “Many large species will almost certainly be the first casualties of our warming, oxygen-poor ocean.”
The research was conduced by Prof Spicer’s University of Plymouth team and the British Antarctic Survey.
Experts analysed four types of crustacean, known as amphipods, which are abundant off coast of the western Antarctic Peninsula.
They found when the gas in their water was reduced, they got smaller – supporting the theory that bigger sea creatures are more vulnerable to climate change, Mirror Online reports.
The study, published in the journal Philosophical Transactions of the Royal Society B, suggests that failure to control greenhouse gases will have a greater impact on marine ecosystems than previously feared.
Prof Spicer said: “Over the past 50 years, the oxygen in our oceans has decreased by around 2-5 per cent. This is already having an effect on species’ ability to function.
“Unless they adapt, many larger marine invertebrates will either shrink in size or face extinction. This would have a profoundly negative impact on the ecosystems of which they are a part.”
Dr Simon Morley, of the British Antarctic Survey , added: “Understanding these impacts will not only help us to predict the fate of marine biodiversity at the poles but teach us much about the mechanisms that will determine the survival of species.”
Previous studies have suggested the fish will shrink by up to a quarter by 2050.
