Strategic Habitat & River Reach Units

ARSN partners focus on targeted watersheds and river corridors across Alabama that are critical for protecting, restoring, and recovering biological diversity. The Strategic Habitat Units (SHUs) and Strategic River Reach Units (SRRUs) help prioritize areas for the management, recovery, and restoration of populations of rare fishes, mussels, snails, and crayfishes.

These units contain a substantial portion of Alabama’s remaining high-quality waterways and reflect the variety of aquatic habitats these species occupy—both historically and presently.

How SHUs and SRRUs Were Selected

These priority areas were identified based on:

  • The presence of federally listed and state imperiled species
  • The designation of critical habitat for these species
  • Expert knowledge about essential habitat components required for these species to survive

What Makes Good Aquatic Habitat?

Suitable habitat for these species includes:

  • Geomorphically stable stream and river channels
  • Suitable flow regimes
  • Water quality within the parameters for thriving species
  • Diverse channel substrate types with minimal fine sediment and filamentous algae
  • Few or no competitive or predatory nonnative species

Collaborative Management

The purpose of designating SHUs and SRRUs is to facilitate watershed management and restoration efforts by addressing habitat and water quality issues. This collaborative approach was led by ARSN partners United States Fish & Wildlife Service, Alabama Department of Conservation & Natural Resources and Geological Survey of Alabama.


Planning and meeting operations are led by four regional working groups based on geographic areas for the USFWS Partners for Fish and Wildlife Program: North, South, East, and West. These working groups conduct meetings as needed in their corresponding regions and create action plans that are presented at the annual ARSN meeting.