A ringed seal pup takes shelter in the snow in Alaska. Photo: Shawn Dahle, NOAA, Polar Ecosystems Program research cruise/Wikimedia Commons
According to the study, winter ice cover in the sea has declined by 35 percent since the 1960s, with consequences for many different species.
“The Baltic ringed seal is dependent on the ice, because they give birth to their pups there and make shelters in snow drifts on the ice, and they therefore need snow cover to propagate,” Henrik Nygård, a scientist at the institute, told Sweden’s state broadcaster SVT.
According to the report, the seals require ice cover for at least five weeks in February and March to raise their pups.
A 2017 report from the World Wildlife Fund estimated that there were between 10,000 and 20,000 ringed seals in the Gulf of Bothnia shared between Sweden and Finland.
The report also warns that the ice’s retreat could also affect whitefish, by increasing the impact of currents on their roe, and increase blooms of blue green algae, affecting the entire food chain.
“Many species and organisms in the Baltic Sea are affected by the reduction in sea ice,” he said.