At a Glance
Beaver Dam Analogs restore ecological function and benefits to New Mexico’s state parks.
Project Description
Before being nearly extirpated by fur trappers in the 1800s, beavers sculpted many of the world’s stream valleys, waters, and wetlands, naturally achieving conditions often sought by today’s conservation and restoration practitioners. For that reason, Beaver-based restoration using structures mimicking the form and function of beaver dams are often useful in ecological restoration.
The State Parks Division of New Mexico’s Energy, Minerals, and Natural Resources Department (EMNRD) wanted to determine if BDAs could be used to regenerate degraded aquatic ecosystems within its state parks. Biohabitats conducted a GIS suitability analysis examining state park properties with overlays of historic beaver ranges and previously documented beaver habitat. Biohabitats also visited completed beaver-based projects in the state to gain insight on how they functioned over time. The analysis revealed that BDAs held strong potential to jumpstart the restoration of ecosystem function and stability at five state parks.
The top priority site, 700-acre Fenton Lake State Park, is bisected by the Rio Cebolla, home to native Rio Grande cutthroat trout. Beaver had existed in the park and created an ecologically rich ponded water environment that was popular for fishing, but high spring flows due to heavy rains overtopped the lake spillway and blew out their dams. With changing weather patterns in mind, and in collaboration with EMNRD’s State Parks Division, state and federal wildlife agencies, and community stakeholders, Biohabitats developed a three-phase design approach to adaptively integrate beaver-based restoration into the Rio Cebolla valley downstream of Fenton Lake. It includes both BDAs and Post-Assisted Log Structures (PALS) that spread heavy flows out into the floodplain while adding habitat complexity. An objective of the work is to attract beaver back to this part of Rio Cebolla.