December 19, 2018 — As atmospheric CO2 levels continue to rise, increasing amounts of carbon dioxide will be absorbed into the ocean. New research suggests rising CO2 levels in the ocean could disrupt the olfactory abilities of coho salmon.
Salmon rely on their sense of smell to track prey, find mates and navigate their way back upstream to spawn. According to the new study, published this week in the journal Global Change Biology, a compromised sense of smell would pose a serious threat to the health of salmon populations.
Lab experiments showed rising acidity levels caused by elevated CO2 levels inhibits salmon’s already vulnerable sensory-neural system.
“Our studies and research from other groups have shown that exposure to pollutants can also interfere with sense of smell for salmon,” Evan Gallagher, a professor of toxicology at the University of Washington, said in a news release. “Now, salmon are potentially facing a one-two punch from exposure to pollutants and the added burden of rising CO2. These have implications for the long-term survival of our salmon.”