Ocean's Rising Acidity is Killing Shellfish

Something is killing off oysters. Farmers of Desolation Sound in Canada have reported a mortality rate of nine-tenths among baby oysters over the last two years and it’s not an isolated incident. Gwynn Guilford of Quartz has written a summary of scientific reports, revealing a grim future for sea life as ecosystems continue to shift and change, and creatures are unable to adapt.

Guilford doesn’t pull any punches as she writes that “British Columbia’s share of Canada’s aquaculture industry is in a tailspin.” Scallops, oysters, clams, and all manner of shellfish farms on Atlantic and Pacific coasts are suffering losses. France and Australia report the destruction of their shellfish while scientists attribute the deaths to a deadly herpes virus, but not everyone agrees. There’s a reason why the disease is running rampant among their populations.

The shifting ecological landscape driven by the rise of industrial pollution has caused pH levels to drop and become increasingly acidic. The average in 1954 and 1974 was 8.1, but has since dropped to 7.2 as of 2001. A pH below 7 is considered acidic, and these levels have been leaving baby clams vulnerable to the elements and disease while they’re unable to grow shells strong enough to protect themselves.

Guilford says scientists attribute this change to the rising CO2 levels. The ocean absorbs nearly one-third of the carbon-dioxide released into the atmosphere, and scientists predict that the ocean will be 170 percent more acidic than it was during the Industrial Revolution by 2100.

She reports farmers means of a solution are to create “buffered hatcheries,” so the shellfish have time to build a strong outer shell—a temporary fix for an issue with broader implications on our environment. However, it’s likely that even if humans are able to reduce pollution the effects of the damages will be felt for years to come.

As of now, the trapped CO2 from the 1960s that has resided deep in the ocean is being welled-up along the Pacific by the summer winds. This additional acidity from winds upwelling this trapped CO2 has made the environment unbearable for these creatures, which has caused higher rates of mortality among babies and disease to spread. It’s a delicate ecosystem that has been compromised and its effects will continue to show themselves for years to come in the environment and in industry.