EagleTribune.com, North Andover, MA

World/National News

October 14, 2012

Oceans' rising acidity a threat to shellfish -- and humans

LOS ANGELES — Peering into the microscope, Alan Barton thought the baby oysters looked normal, except for one thing: They were dead.

Slide after slide, the results were the same. The entire batch of 100 million larvae at the Whiskey Creek Shellfish Hatchery had perished.

It took several years for the Oregon oyster breeder and a team of scientists to find the culprit: a radical change in ocean acidity.

The acid levels rose so high that the larvae could not form their protective shells, according to a study published this year. The free-swimming baby oysters would struggle for days, then fall exhausted to the floor of the tank.

“There’s no debating it,” said Barton, who manages Whiskey Creek, which supplies three-quarters of the oyster seed to independent shellfish farms from Washington to California. “We’re changing the chemistry of the oceans.”

Rising acidity doesn’t just imperil the West Coast’s $110 million oyster industry. It ultimately will threaten other marine animals, the seafood industry and even the health of humans who eat affected shellfish, scientists say.

The world’s oceans have become 30 percent more acidic since the Industrial Revolution began more than two centuries ago. In that time, the seas have absorbed 500 billion tons of carbon dioxide that has built up in the atmosphere, primarily from the burning of fossil fuels.

By taking in that amount — more than one-quarter of the greenhouse gas that has accumulated in the atmosphere — the oceans have buffered the full effects of climate change, scientists say: Temperatures have not risen as much as they would have otherwise, glaciers haven’t melted as fast. Yet the benefits are coming at a cost to marine life, especially oysters, clams and corals that rely on the minerals in alkaline seawater to build their protective shells and exoskeletons. The ill effects of the changing chemistry only add to the oceans’ problems, which include warming temperatures and expanding low-oxygen “dead zones.”

Text Only | Photo Reprints
Latest News
World/National News

Latest U.S. News
Dangerous Bacteria Kills One in Florida Visitors Feel Part of the Pack at Wolf Preserve 3 People Killed, Deputies Wounded in NC Shootout Suing Obama: GOP-led House Gives the Go-ahead Obama: 'Blood of Africa Runs Through My Veins' Amid Drought, UCLA Sees Only Water Texas Scientists Study Ebola Virus Smartphone Powered Paper Plane Debuts at Airshow Air Force: Stowaway Triggers Security Review Minnesota Fire Engulfs Home, Two Garages Southern Accent Reduction Class Cancelled in TN Obama Chides House GOP for Pursuing Lawsuit New Bill Aims to Curb Sexual Assault on Campus 3Doodler Bring 3-D Printing to Your Hand Six PA Cops Indicted for Robbing Drug Dealers Officials Unsure of UCLA Flood Repair Date At Least 20 Chikungunya Cases in New Jersey Raw: Obama Eats Ribs in Kansas City Broken Water Main Floods UCLA Raw: Amphibious Landing Practice in Hawaii
Latest World News
Workers Dig for Survivors After India Landslide Fighting Blocks Access to Ukraine Crash Site Raw: Smoke, Explosions Fill Gaza Skyline Today in History for July 31st Raw: 16 Killed in Gaza Market Strike Raw: Guinea Rap Concert Stampede Kills 33+ Raw: Deadly Landslide Hits Indian Village Graphic Video: 15 Killed at Gaza UN School Russia Counts Cost of New US, EU Sanctions Britain Testing Driverless Cars on Roadways Raw: Floodwaters Ravage Villages in Romania Raw: Thousands Flocking to German Crop Circle Raw: Otters Enjoy Water Slides at Japan Zoo Raw: Amphibious Landing Practice in Hawaii Raw: Weapons Fire Hits UN School in Gaza Raw: Rocket Launches Into Space With Cargo Ship Today in History for July 30th Raw: Aftermath, Artillery Shells Hit Donetsk Muslims Celebrate Eid El-Fitr Around the World Gaza Official: at Least 100 Killed Tuesday
Photos of the Week