One of the ocean's tiniest species, and a major food source for many sea creatures, is going extinct.
Cold water plankton is not adapting well to the world's warming seas, and this is bad news for fisheries, a Deakin University of Australia news release reported.
Fishermen in the North Atlantic rely on fish such as cod and hake to stay afloat, but these fish feed on primarily cold water plankton.
"There is overwhelming evidence that the oceans are warming and it will be the response of animals and plants to this warming that will shape how the oceans look in future years and the nature of global fisheries," Deakin's professor of marine science, Graeme Hays, said.
"We know that warm water species are expanding their ranges as warming occurs, and vice versa. What is not known is whether species are able to adapt to new temperatures. Will, for example, cold water species gradually adapt so they can withstand warming seas and not continually contract their ranges. From the results of our study, it is looking like the answer is no," he said.
The team examined a "50-year time series" of the adaptation of two types of plankton: Calanus helgolandicus which thrives in warm water and Calanus finmarchicus which is a cold water dweller.
They found that the range of area where the cold-water Calanus finmarchicus was able to live shrank over the years.
"The consequences of this study are profound. It suggests that cold water plankton will continue to become scarcer as their ranges contract to the poles, and ultimately disappear. So certainly for these animals, thermal adaptation appears unlikely to limit the impact of climate change," Hays said.
These findings could mean North Atlantic fisheries may soon need to pack their bags.
"Ocean warming is occurring globally and so these findings are likely to apply to other areas around the world including southern hemisphere locations such as Australia, South Africa and South America that support important fisheries dependant on plankton," Hays said.
