Do you love fish and chips? If the answer is yes, we've got some bad news.
The classic cod or haddock in crispy batter could be off the chip shop menu in the future because of climate change, according to a new study.
Rising sea temperatures will cause there to be less oxygen in the water meaning the fish will struggle to survive.
Researchers looked at different sized sea creatures in the the Antarctic, and discovered that when oxygen in the sea went down, fish and other creatures got smaller.
Professor John Spicer, a marine zoologist at the University of Plymouth, has spent more than 30 years examining the effect of climate change on sea life.
He said: "Over the last 50 years, the oxygen in our oceans has decreased by around two to five percent and this is already having an effect on species."
Professor Spicer also warned that many marine animals will shrink in size or face extinction. "This is obviously a major cause for concern," he said.
"Many large species will almost certainly be the first casualties of our warming, oxygen-poor ocean."