Local mussels now endangered, habitat federally protected
Two Texas pimpleback mussels in shallow water. This species is native to the Colorado River Basin and is now protected under the Endangered Species Act. U.S. Fish and Wildlife Service photo
The Colorado and Llano rivers are home to five out of seven species of freshwater mussels recently protected by the Endangered Species Act. The Texas fatmucket, Texas pimpleback, false spike, Balcones spike, and Texas fawnfoot all can be found in bodies of water across the Highland Lakes area.
The other two endangered species, the Guadalupe fatmucket and Guadalupe orb, are farther south in watersheds that share their names.
The U.S. Fish and Wildlife Service listed the seven native species on June 4. They will officially be added to the endangered list on July 4. The new designation comes with federal protections for the at-risk shellfish, and 1,577 miles of river identified as critical habitat for the creatures.
“The (Highland Lakes) themselves are not (designated critical habitat) for the mussel species that will be listed,” LCRA Public Information Officer Clara Tuma said in a written statement to DailyTrib.com. The LCRA collaborated with the service as the endangered mussel designations rolled out. “However, some tributaries to the Highland Lakes could be subject to additional federal permitting requirements due to the presence of the mussels or their designated critical habitat.”
Those tributaries include long stretches of the Llano River behind the Llano City Dam and large portions of the Colorado and San Saba rivers north of Lake Buchanan. Much of the Pedernales River also will be protected.
“These unique freshwater mussels are found nowhere else in the world but in the rivers and streams of Central Texas,” said Amy Leuders, southwest regional director for the U.S. Fish and Wildlife Service. “Saving these mussels isn’t just about preserving the biodiversity of the region, it also helps protect the waterways that people rely on for water and recreation. We are committed to working with local communities to ensure they have the tools they need to protect and recover these imperiled species.”
Animals under the Endangered Species Act are protected by federal law from being killed, collected, or transported. The Fish and Wildlife Service is also required to develop population recovery plans for each species and ensure essential habitat is protected.
Acts of interference with mussel habitat includes excessive livestock grazing near a now-protected waterway, modification of a river or stream with a dam or other construction, or the discharge of chemicals or fill material into protected waters. Federal permitting will be required for projects that might interfere with rivers in an endangered mussel species’ home range.
Protections will make it more difficult to dredge, mine for sand, build, or do anything that could disturb the river bottoms and streams that are now protected.
According to the Fish and Wildlife Service, the now-endangered mussels were once abundant throughout the Colorado, Guadalupe, Brazos, and Trinity river basins, but their populations have declined due to reduced water quality and habitat destruction.
Freshwater mussels like fatmuckets, pimplebacks, spikes, and orbs live submerged in the substrate of river bottoms. These small filter feeders can clean up to 10 gallons of water per day and help keep waterways clean. The protected mussels are different from the invasive zebra mussel, which adheres to plumbing, boats, and structures in massive numbers, causing headaches for waterfront residents and municipal utilities.