SAN ANGELO, Texas— The Center for Biological Diversity today filed a motion to intervene in a lawsuit brought by Texas that seeks to strip Endangered Species Act protections from seven imperiled freshwater mussels.

“These mussels are living indicators of the health of Texas rivers and when they disappear it’s a warning that our freshwater ecosystems are in trouble,” said Lindsay Reeves, senior attorney at the Center. “We’re stepping in to defend their crucial Endangered Species Act protections. If Texas succeeds in overturning these safeguards it could push these amazing creatures even closer to extinction.”

In June 2024, following years of litigation and advocacy by the Center, the U.S. Fish and Wildlife Service listed the Texas fatmucket, Guadalupe fatmucket, Guadalupe orb, Texas pimpleback, Balcones spike and false spike as endangered, and the Texas fawnsfoot as threatened. The final rule also designated more than 1,577 miles of protected critical habitat across the Brazos, Colorado and Guadalupe river basins.

Freshwater mussels are among the most endangered groups of animals in the United States. Sometimes called the “liver of the river,” mussels filter water and stabilize streambeds. A single mussel can clean up to 15 gallons of water a day, removing algae, sediment, bacteria, pharmaceuticals and even viruses. Their disappearance signals serious threats to water quality, biodiversity, and ecosystem health.

The Center sued the Service in 2021 and 2023 to compel the agency to decide whether it would protect the mussels after years of delay. They were finally protected last year. Texas’ lawsuit now seeks to undo those protections, threatening not just the species but the government’s ability to safeguard imperiled wildlife in the face of extinction.

Background
False spikes were once common in Texas but thought to be extinct until they were rediscovered in 2011 in the Guadalupe River. These mussels have only one known population.

Balcones spikes were first described as a species in 2020, but are already rare. There are currently only three populations in the Little River, Lower San Saba River and Llanos River.

Texas fatmucket mussels live only in the upper reaches of major tributaries within the Colorado River basin and only five populations remain.

Guadalupe fatmuckets were recently discovered to be a separate and distinct species from the Texas fatmucket. The mussels are currently found in just one population in the Guadalupe River basin.

Texas pimpleback are small mussels that may live as long as 72 years. The Texas pimpleback currently survives in five isolated populations in the Concho River, Upper San Saba River, Lower San Saba River/Colorado River, Llano River and the Lower Colorado River, but only two of those populations are reproducing.

Guadalupe orbs are found in just two populations in the Guadalupe River and were also recently discovered to be their own species, separate from the Texas pimpleback.

Texas fawnsfoot mussels are found in just seven populations, which live in the Trinity River, Clear Fork Brazos River, Upper Brazos River, Middle/Lower Brazos River, San Saba/Colorado Rivers and Lower Colorado River.