By Randy Shore
Ten million scallops that have died in the waters near Qualicum Beach due to rising ocean acidity are the latest victims in a series of marine die-offs that have plagued the West Coast for a decade.
Human-caused carbon dioxide emissions in the atmosphere are being absorbed by the ocean and may have pushed local waters through a “tipping point” of acidity beyond which shellfish cannot survive, according to Chris Harley, a marine ecologist at the University of B.C.
Rising ocean acidity is a global phenomenon, made worse by higher natural acidity in local waters, Harley said.
“I’ve seen pH measured down to about 7.2, so this is very much within the realm of possibility, though unfortunate and extreme,” he said. “We are in a hot spot in the Pacific Northwest.”
The lower the pH, the higher the acidity. Local waters are typically a much-less-acidic 8.2.
High acidity interferes with the ability of baby scallops to form a protective shell, forcing them to expend more energy and making them more vulnerable to predators and infection.