About this Collection

Eight species freshwater mussels are currently listed as endangered in Texas and one species is listed as threatened. An additional 3 species have been proposed to receive endangered species status in the state and 1 more is proposed to receive threatened status. The following documents and links are provided to help you understand the life history, federal listing status, recovery efforts, and sampling recommendations of these species.

NEWS: The Final Central Texas Freshwater Mussel Rule has been published in the Federal Register.  This rule and supporting documentation, including a recovery outline for the species can be found at: https://www.fws.gov/library/collections/central-texas-freshwater-mussels-final-rule-and-supporting-documents

This library collection includes information pertaining to the listed or proposed freshwater mussel species in Texas.  The information is organized into five sections: Species, Maps and Data, Recovery, and Permitting.

  1. Species -  includes links to each individual species page.
  2. Maps and Data – includes links to information on designated critical habitat and publicly available presence/absence data
  3. Freshwater Mussel Sampling Protocol
  4. Recovery – includes links to current freshwater mussel recovery plans for species in Texas.
  5. Permitting – includes links to Section 10(a)(1)(a) or scientific permit information.


There are currently 12 species of freshwater mussels in Texas that are either currently listed under the Endangered Species Act (Act) or have been proposed to receive listing under the Act.  These species mussels generally occur in medium to large streams and rivers and require adequate amounts of flowing water, free of contaminants and water quality degradations and having adequate food supply, with refugia from both high- and low-flow events, appropriate substrate that is generally characterized as stable and free of excessive fine sediment, access to appropriate fish hosts, and habitat connectivity (i.e., lack of excessive impoundments and barriers to fish passage fish passage
Fish passage is the ability of fish or other aquatic species to move freely throughout their life to find food, reproduce, and complete their natural migration cycles. Millions of barriers to fish passage across the country are fragmenting habitat and leading to species declines. The U.S. Fish and Wildlife Service's National Fish Passage Program is working to reconnect watersheds to benefit both wildlife and people.

Learn more about fish passage

Links to more information about each species and links to the Texas Freshwater Mussel Survey Protocol (Protocol) is designed by the Texas Parks and Wildlife Department (TPWD) and the U.S. Fish and Wildlife Service (Service)  are provided below.  

Maps and Data

  • Critical Habitat: The U.S. Fish and Wildlife Service provides final critical habitat designation information for threatened and endangered species across the United States using an online mapper and by providing data that can be downloaded for use in a Geographic Information System (GIS).   You can find both the mapper and the data on the Critical Habitat Report web page. For individual species data, scroll down the Critical Habitat Report page and enter the species into the search box.
  • Mussels of Texas Database: Texas A&M University maintains an online database of freshwater mussel records throughout Texas that is accessible using an online mapper. The Mussels of Texas Database is a tool for research and informal project scoping purposes.  Note that the database is not a formal project planning tool to satisfy regulatory consultation with the U.S. Fish and Wildlife Service.  Formal project planning should still be completed using IPaC.

Texas Freshwater Mussel Sampling Protocol

This Protocol was designed to determine the presence or probable absence of freshwater mussels inside the footprint of or within the immediate vicinity of proposed construction projects with instream impacts. The methods and requirements described herein were developed to provide standardized procedures for a variety of frequently encountered projects and were intended to be applicable to all streams and impoundments that may be occupied by freshwater mussels in Texas. For projects or stream segments that are not adequately described or covered by the Protocol, additional coordination with TPWD and/or the Service may be necessary to determine project-specific methods and/or requirements.


Recovery Plans - To help identify and guide species recovery needs, section 4(f) of the Endangered Species Act of 1973, as amended, directs the Service to develop and implement recovery plans for listed species or populations.  Recovery plans are advisory documents developed to provide recovery recommendations aimed at resolving the threats to the species and ensuring self-sustaining populations in the wild.  There are currently two recovery plans that apply to the Texas Freshwater Mussels.


Section10(a)(1)(A) permits, also referred to as recovery, enhancement of survival, or scientific permits, allow for 'take' of listed species that may or will occur while conducting research to further the recovery of a listed species. 

To apply for a scientific research and recovery permit to conduct presence/absence surveys or do research on endangered or threatened species, you will need to fill out Form 3-200-59. This form and instructions for filling it out can be found on our ePermits website.

Section 10(a)(1)(A) Scientific Permit Applicant Guidelines for Conducting Presence/Absence Surveys, Translocations, and Research of Endangered and Threatened Freshwater Mussels in Texas can can be found in the accompanying document library.