CContributions to Delisting Rio Grande Silvery Minnow: Egg Habitat Identification
* What Reclamation operations affect minnow egg and nursery habitat?
* How can Reclamation make water deliveries reliable and contribute to the recovery of the Rio Grande silvery minnow?
* Can Reclamation create habitat where it maximizes species benefits and minimizes water use to meet obligations to a variety of stakeholders?
Need and Benefit
The majority of the existing populations of endangered silvery minnow currently reside between the San Acacia Diversion Dam and Elephant Butte Reservoir; this section of the Rio Grande is ephemeral, especially during the irrigation season. At present, water is purchased by Reclamation and released during the summer to keep this section of the Rio Grande wet. The long-term solution for preserving this species is to create a stable population upstream in the perennial section of the Rio Grande. In order to accomplish the upstream establishment of a silvery minnow population, nursery habitat must be created to retain the silvery minnow eggs and larva in the perennial reach. This research is focused on determining the critical features of nursery habitat and how to reproduce them in future restoration projects.
Results from this project will be used to design more effective habitat restoration projects for the endangered silvery minnow in the perennial section of the Rio Grande. Improving existing habitat and providing new habitat for the minnow is considered essential for restoring a healthy population for the silvery minnow (US Fish and Wildlife [FWS] Biological Opinion, 2001). Increasing upstream populations of silvery minnows will minimize the quantities of water required for silvery minnow conservation while improving the status of the species.
Between 2000 and 2002, Reclamation has spent more than twelve million to provide supplemental water for the Rio Grande silvery minnow. The 2003 FWS Biological Opinion recommends continuing this expenditure of funds for supplemental water.
Water and Environmental Resources Office, Office of Program and Policy Services
Contact the Principal Investigator for information about these documents.