Manila clams, a popular global delicacy known to also be invasive, could come to the Chesapeake Bay — but might not necessarily harm the ecosystem, experts say.
The exotic species originally from Asia was recently discovered near the northwestern Atlantic coastline off Cape Cod, Massachusetts, one of the last places in the northern hemisphere to remain free of the mollusk, a collaborative team of marine biologists found.
Manila clams make up one of the most heavily cultivated and commercially valuable species in the world. The shellfish, however, can become invasive through its rapid breeding and overtaking native ecosystems, marine ecologist Aly Putnam, who was the paper’s lead author, told The Baltimore Sun.
Matt Gray, a professor in the ecophysiology of bivalves at University of Maryland, told The Sun the saltwater clams would be more likely to populate in the south of the Chesapeake, near Virginia, rather than Maryland because of the saltiness and depth of the water.
“We’ve got all the right habitat, enough food and it’s warm enough to support their reproduction and for them to do well down there,” Gray said.
Experts said the mollusks would have to push against gulf streams to eventually land in the Chesapeake, but could accidentally get moved through ships, both commercial and recreational.
Although the clam is invasive in other ecosystems, until they’re physically in the Chesapeake, it’s unknown whether they would initially cause harm, experts said.
Putnam said the clams can end up being a food resource for different animals in different ecosystems, which is a positive.
Changes in climate, water temperatures and salinity levels make it harder to predict if a species will adapt or impact existing ecosystems, said Julie Luecke, Chesapeake Bay Foundation’s Maryland coastal resource scientist, in a statement to The Sun.
Luecke pointed to a nonnative species such as zebra mussels in the Chesapeake directly harming or outcompeting native freshwater mussels.
An exotic species like Manila clams would generally take away resources that would be put into growing native species and their ecosystem services, Gray said.
“I think it’s bad because we’ve got enough problems with our own clams and oysters that we don’t need additional competitors,” Gray said. “But I just want to say that, if it shows up here, it doesn’t necessarily mean it would be invasive.”
I find it amusing that they're worried about a new clam could take away phytoplankton from other filterfeeders, like oysters and native clams. In Chesapeake Bay, for years our main concern has been too much phytoplankton fueling anoxia.
