Freshwater ecosystems are experiencing declines in biodiversity far greater than those in the most affected terrestrial ecosystems. This decline has been especially severe for certain groups of aquatic biota, including freshwater mussels (Unionidae). Freshwater mussels are considered the most imperiled of all aquatic fauna. Of the 300 mussel species known to have occurred in the United States, 12 percent are thought to be extinct and 23 percent are considered threatened or endangered.
The 52 described species in Texas have been impacted as well. Statewide declines in distribution and abundance have led to the listing of 15 Texas species as state threatened in 2009, 12 of which either are designated as a candidate for listing under the Endangered Species Act (ESA) or are still being considered for protection under the ESA.
The freshwater mussel program of the Texas A&M Institute of Renewable Natural Resources (IRNR) and Texas Water Resources Institute strives to improve the knowledge of the distribution, life history characteristics, and conservation status of freshwater mussel populations throughout the state.