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Texas hornshell Popenaias popeii
ESA status: candidate for listing
The Texas hornshell is the last remaining native mussel in New Mexico: all of the seven other mussel species in the state have been extirpated. The hornshell was confirmed to exist along an eight-mile segment of the Black River (a tributary of the Pecos River) in 1996, where it had not previously been seen since the 1930s. In Texas, 48 dead hornshells have been found in the Rio Grande in Big Bend National Park in surveys starting in 2005. Two live hornshells were found in the Devil’s River and one was found within the Rio Grande Wild and Scenic River downstream of Big Bend in 2008. An extant population is believed to occur in the Rio Grande near Laredo, and dead shells were found in the Llano River in Llano County and South Concho River in Tom Green County (both tributaries of the Colorado River) in 2004.
The U.S. Fish and Wildlife Service designated the Texas hornshell as a candidate for listing under the Endangered Species Act in 1989. The agency identified a battery of threats to the species, including alteration of stream habitat from land uses; water pollution; water diversion and groundwater pumping; contamination from oil and gas operations; siltation and sedimentation; and a lack of legal protections.
Freshwater mussels require perennial river flow, adequate water quality, and suitable substrates. The widespread loss of mussels and habitat in the Southwest is evidence of our mismanagement of these riverine environments. Protecting the Texas hornshell under the Endangered Species Act may assist in preventing this species from becoming the next mussel to vanish from Southwestern waterways and can help bring some of the region’s rivers and streams back to life.
- Significant Actions
- April 2009 - "America's Top 40" (report)
- May 2011 - Texas hornshell included in landmark settlement with the U.S. Fish and Wildlife Service
- Press Releases
- April 30, 2009 - "America's Top 40: Full of Sad Songs for Endangered Species"
- November 10, 2010 - "Federal Endangered Species Listing Program Still Lags"
- May 10, 2011 - “Hope for Endangered Species Act Candidates”
- September 9, 2011 - “Federal Court Approves Historic Species Agreement"
- Species Factsheet
- Related Campaigns