A dangerous invasive mollusk has been discovered in the Port of Stockton, and the species could threaten water systems across the Delta, the California Department of Fish and Wildlife reports.
A non-native bivalve called the golden mussel was recently found in the port. It also is suspected to have invaded O’Neill Forebay in Merced County, about 80 miles south of Stockton.
Fish and Wildlife officials say it’s the first time golden mussels have been encountered in North America.
“The species poses a significant immediate threat to the ecological health of the Delta and all waters of the state, water conveyance systems, infrastructure and water quality,” the department said in a statement.
After the Stockton discovery, the department has been scouring the Delta for other suspected golden mussels, which are being tested for confirmation. If the new infestation isn’t confronted immediately, the freshwater invaders could spread to other waterways and ports in the state, officials warn.
“If we’re lucky, and we stage a real eradication effort in the area where it’s presently found, it might not be too costly and would be worth it,” UC Davis biologist Peter Moyle told CalMatters.
Though small — the mussels are little more than half an inch and up to 2 inches in length — they can encrust water pipes and clog them. They can attach themselves to ship hulls or be released when ballast water is discharged.
The mussels found in Stockton were likely carried into port by a visiting ship, officials said.
The species could easily spread throughout the Delta. And the threat goes beyond just fouling water pipes, Fish and Wildlife authorities warn. The mussels may endanger native species, and because they are voracious filter-feeders, they could also decrease water clarity.
Golden mussels, or Limnoperna fortunei, are named for the golden or yellowish hue of their shell. They thrive in the rivers and creeks of China and Southeast Asia, but have traveled extensively around the Pacific Rim. They have been found in Hong Kong, Japan, Taiwan, Brazil, Uruguay, Paraguay and Argentina.
To stop their spread in the Delta, authorities are calling on boat owners to clean, drain and dry their vessels whenever they haul them out of the water. Boat inspections have already begun in O’Neill Forebay, situated west of Los Banos. And officials are asking anyone who encounters mussels they suspect are the golden variety to report the finding to Fish and Wildlife.
Though the golden mussel may be new to the U.S., it’s not the first time California wildlife experts have had to try to eliminate invasive bivalves. The quagga and zebra mussels continue to be a concern.