Meet the tiny, translucent “sea butterfly,” whose home is currently being transformed into an acid bath. Off the US’s west coast, there are anywhere between 100 and 15,000 of these free-swimming sea snails per square meter. And the oceans are beginning to dissolve the tiny shells right off their backs.
A new study, among the first to examine how the process called ocean acidification impacts marine life, has confirmed that about half of all the pteropods off the west coast are fighting off the acid burn. It builds on previous work that has shown pteropods dissolving in other waters; it’s a disturbing trend, considering they’re a key link in the oceanic food chain.
The world’s oceans have absorbed a third of humans’ carbon emissions, a process that increases their acidity. Scientists have long noted the changing chemistry of the waters, and voiced concern that this leaves calcium-based creatures, like coral and pteropods, extremely vulnerable. Now, it appears, they have proof.
“These are some of the first insights into how marine creatures are affected by acidification,” Dr. Nina Bednarsek told me in a phone interview. She’s the lead author of the National Oceanographic and Atmospheric Administration study, which was just published in the Proceedings of the Royal Society B. The research determined that “large portions of the shelf waters are corrosive to pteropods in the natural environment.”
“Fifty percent of those pteropods are affected by acidification,” Bednarsek said. “It’s a lot—more than we expected.” And sooner. She tells me that acidification is happening sooner and on a larger scale than scientists predicted. “This is just an indication of how much we are changing the natural environment,” she said.