Ocean Acidification Dissolving Shells of Key Marine Creature

Scientists have documented how ocean acidification, sometimes referred to as climate change’s “evil twin,” is already taking a toll on an essential part of the marine food chain in an area off the U.S. northwest coast, and with runaway greenhouse gas emissions continuing, it looks like the problem is only set to worsen.

As oceans have absorbed increasing amounts of CO2, they’ve become more acid, and that means the shells of pteropods, small, free-swimming marine snails, are dissolving — a change the researchers hadn’t expected to see for years.

In samples they took from northern Washington to central California, 53 percent of the pteropods had severely dissolved shells.

“Our findings are the first evidence that a large fraction of the West Coast pteropod population is being affected by ocean acidification,” stated lead author Nina Bednarsek, Ph.D., of NOAA’s Pacific Marine Environmental Laboratory in Seattle. “Dissolving coastal pteropod shells point to the need to study how acidification may be affecting the larger marine ecosystem.”

The tiny snails, which are about one-eighth to one-half inch in length, are a food source for pink salmon, mackerel and herring, so a plummet in the pteropod population will have far-reaching effects.

The team of NOAA-led researchers warns that