Saving Seafood

Dead zones, a ‘horseman’ of climate change, could suffocate crabs in the West, scientists say

July 30, 2021 — As the Pacific Ocean’s cool waters hugged Oregon’s rugged shore, Nick Edwards, a seasoned commercial fisherman, could not believe his eyes. Stretching over at least 100 yards, he said, were the carcasses of hundreds of Dungeness crabs piled in the sands of a beach south of Cape Perpetua.

The remains of what Edwards deemed “the crème de la crème of seafood” — also one of the state’s most prized fisheries — are the most visible byproduct of a process that usually goes unnoticed by most beach-dwellers: hypoxia, or the emergence of swaths of low-oxygen zones in marine waters.

Hypoxic areas in Oregon, researchers found, have surfaced every summer since they were first recorded in 2002 — leading scientists to determine a recurring “hypoxic season,” akin to wildfire and hurricane ones.

However, climate change has exacerbated its effect, said Francis Chan, the director of the Cooperative Institute for Marine Resources Studies at Oregon State University, resulting in increasingly frequent and extensive hypoxic areas that can morph into “dead zones,” where the total lack of oxygen kills off species that cannot swim away, much like the Dungeness crabs.

Read the full story at The Washington Post

West Coast Ocean Acidification Rates Among Highest In World

June 2, 2017 — Carbon emissions aren’t just causing climate change, they’re having a profound effect on ocean chemistry.

Our oceans are becoming more acidic and this is a major threat to fisheries.

Researchers have now recorded some of the highest levels of ocean acidification in the world,  right off the coast of the Pacific Northwest.

When oceans absorb carbon, they become more acidic, preventing oysters and tiny marine snails at the base of the food chain from forming shells.

A new study from Oregon State University documents ocean acidification off the coast of California and Oregon.

“What we didn’t know is that if you’re an animal living on the shore, how often do you see a bad day?” Francis Chan, a lead author, said. “And now because we have sensors that are actually taking a measurement of ocean PH every 10 minutes throughout the summer, we can start to build that picture.”

The study found that while there were persistent hotspots of destructive acid levels, there were also areas that stayed within healthy ranges.

Read the full story at Northwest Public Radio