Scientists have found a link between melting Arctic sea ice and the emergency of a virus that is deadly to sea lions, ice seals, sea otters and other marine mammals in the North Pacific.
A new study from the University of California, Davis has identified how a virus responsible for killing thousands of European harbor seals in the North Atlantic in 2002 was found two years later in northern sea otters on the other side of the continent in Alaska: climate change.
According to the 15-year study, melting Arctic sea ice may have opened pathways for contact between Arctic and sub-Arctic seals that was previously impossible, allowing for the virus’ introduction into the Northern Pacific Ocean.
“The loss of sea ice is leading marine wildlife to seek and forage in new habitats and removing that physical barrier, allowing for new pathways for them to move,” said Tracey Goldstein, one of the study’s authors.
“As animals move and come in contact with other species, they carry opportunities to introduce and transmit new infectious disease, with potentially devastating impacts.”
The researchers sampled marine mammals for virus exposure and infection from 2001-2016. They also assessed Arctic ocean sea ice and open water routes from the North Atlantic to North Pacific oceans.
They discovered that peaks in virus infection and exposure coincided with reductions in Arctic sea ice extent.
“As sea ice continues its melting trend, the opportunities for this virus and other pathogens to cross between North Atlantic and North Pacific marine mammals may become more common,” said first author Elizabeth VanWormer.
Image credit: NOAA Fisheries, Polar Ecosystems Program