July 15, 2019 — Global climate change poses a severe threat to marine life, but scientists have found at least one species that appears to be successfully adapting to warmer ocean waters.
A recent study published in the Proceedings of the National Academy of Sciences found that, even without factoring in the impacts of fishing, global animal biomass in Earth’s oceans is expected to decrease by as much as 17 percent by 2100 under a “high emissions” scenario that leads to 3-4 degrees Celsius of warming. Even under a “low emissions” scenario, in which global warming is limited to just 2 degrees Celsius (the goal of the Paris Climate Agreement), the study found that marine life biomass would drop by 5 percent by 2100.
In addition to warmer waters, ocean acidification and oxygen depletion will take a toll on the wildlife that call Earth’s oceans home. On average, the research determined, we can expect a 5 percent decline in ocean life for every 1 degree Celsius increase in Earth’s average surface temperature.
However, a new study published in the journal Marine Ecology Progress Series shows that, as ocean temperatures rise, Atlantic surfclams, a large saltwater clam found mostly in the western Atlantic Ocean, are capably shifting their range into waters that would have previously been inhospitable to their survival.
According to the study’s authors, Jeremy Timbs and Eric Powell of the University of Southern Mississippi and Roger Mann of the Virginia Institute of Marine Science, the number of larvae produced by Atlantic surfclams is the key to the species’ adaptability. The clams employ a strategy of producing a massive amount of larvae that are widely distributed throughout the ocean, allowing them to reproduce despite the deleterious effects of predators, lack of food, and inhospitable temperatures on surfclam larvae numbers.