Shellfish
Shellfish such as oysters, clams, crabs, and scallops provide food for marine life and people too. Importantly, shellfish make their shells from calcium carbonate, which contains carbonate ions as building blocks. The decreases in the concentration of these building blocks in seawater with ocean acidification can directly affect building and maintaining calcium carbonate structures. This may impact their survival, growth, and physiology and the food webs and economies that depend on them.
Dungeness Crab
Dungeness crab (Cancer magister) support an economically and culturally important commercial fishery along the U. S. West Coast. This crab also plays important roles in pelagic food webs in their early life-stages and benthic food webs as juveniles and adults. Scientists at the Northwest Fisheries Science Center and collaborators from the Suquamish Tribe have previously documented lower survival and slower development of Dungeness crab during a young larval stage. Current research aims to understand why these negative effects occur and where in the ocean these biological effects may be observed, which could make Dungeness crab a useful biological indicator of ocean acidification on the U.S. West Coast.
Geoduck Clams
The geoduck (pronounced gooey-duck; Panopea generosa) is a long-lived, massive, burrowing clam native to coastal waters of the Northwest Pacific. Geoducks are harvested from the wild by clammers and are also grown in aquaculture. In Washington State’s Puget Sound, the wild geoduck fishery, enacted primarily by tribal fisheries, is worth $32 million annually, and geoduck aquaculture has recently experienced significant growth. Because of the species’ economic and cultural importance, scientists at the Northwest Fisheries Science Center have studied geoducks in different ocean chemistry conditions, looking at their survival, development, and genetics. The genetics research explored whether the species has the potential to adapt to ocean acidification.
King & Snow Crabs
Many species of king crab live within Alaskan waters, including red king crab (Paralithodes camtschaticus), golden king crab (Lithodes aequispinus), Tanner crab (Chionoecetes bairdi), and snow crab (Chionoecetes opilio). All four species support important commercial fisheries in Alaska. Laboratory experiments at the Alaska Fisheries Science Center have shown that juvenile crabs are negatively impacted by ocean acidification, which causes reductions in their growth and survival. Recently, the research team was able to link these laboratory observations to real-world impacts on a wild population. They found that the population decline of the red king crab, which has resulted in multi-season closures of a Bristol Bay, Alaska fishery, is connected to changing ocean chemistry. This is the first time the decline of a wild fisheries stock has been shown to be due to ocean acidification.
Surf Clams
Atlantic surf clams (Spisula solidissima) occur in eastern North Atlantic waters and are commercially fished off the coasts of Massachusetts, New Jersey, Delaware, Maryland, and Virginia. Researchers at the Northeast Fisheries Science Center, in collaboration with scientists at Rutgers University, are conducting experiments investigating the effects of ocean acidification on the development of early life stages of surf clams. The experiments are done in the laboratory and under commercial farm-scale conditions in the coastal ocean, providing data that helps the surf clam fishing industry manage aquaculture efforts.
Sea Scallops
Sea scallops (Placopecten magellanicus) support a highly valuable commercial fishery in the U.S. northeast. Scientists at NOAA’s Northeast Fisheries Science Center and Wood’s Hole Oceanographic Institution conducted laboratory experiments examining the interactive effects of ocean acidification and other potential stressors on larval growth and shell formation. They found that warming temperatures and ocean acidification hinders growth. Read more
Blue Mussels
Blue mussels (Mytilus edulis) are economically important shellfish that are sensitive to chemical stressors including ocean acidification and metal toxicity. Researchers in Maine, where the blue mussel aquaculture industry provides millions of dollars to the state economy, are studying how different diets can improve blue mussel resilience to ocean acidification. Diet enhancement is a potential mitigation strategy that could support shellfish aquaculture at commercial scales. The sensitivity of blue mussels to changing ocean chemistry has also been studied at NOAA National Centers for Coastal Ocean Science, where scientists tested how blue mussels accumulate contaminants like metals in their bodies under acidified conditions. This work will help inform managers of shellfish aquaculture and ensure our seafood is safe to consume.
Pacific Oysters
Pacific oysters (Crassostrea gigas) are an important aquaculture species on the U.S. West Coast and provide ecosystem services, improving water quality by filter feeding and forming reef habitat for other marine species. Scientists from the Northwest Fisheries Science Center and the University of Washington are working with shellfish growers to study the biological sensitivity of Pacific oysters in the laboratory and in the field, examining how different genomes influence their tolerance to changing ocean chemistry.
