A part of the national refuge system managed by the U.S. Fish and Wildlife Service, Imperial National Wildlife Refuge (INWR) was established in 1941 as a refuge to protect backwaters and marshes for waterfowl along the lower Colorado River. Located roughly 20 miles North of Yuma, conservation at the refuge today employs a variety actions that focus on management of habitat, terrestrial and aquatic wildlife. In a cooperative effort with the Department and other partners, INWR has actively managed a refuge population of Desert Pupfish since March 6, 20001. Although not a particularly large pond, the INWR pond appears to have the capacity for a relatively large population. Based on mark-recapture data generated during monitoring in 2009, the population reached a height of 4537 individuals 2. By 2012 however, survey data provided a greatly reduced estimate of 671 individuals, which is probably more typical of this and other ponds this size. Today, the pond at INWR continues to support a thriving and healthy population of Desert Pupfish.

1 Minckley, C.O. 2002. Population Estimate for Refugia Populations of Desert Pupfish on Imperial and Cibola National Wildlife Refuges. Federal Document: USFWS-AZFRO-PA-02-001.

2 Knecht, T. 2012. 2012 Desert Pupfish Population Estimates Imperial, Cibola, and Bill Williams River National Wildlife Refuges. Federal Document: USFWS-AZFRO-PA-13-001.


Pupfish refuge pond at the Imperial National Wildlife Refuge (Photo: U.S. Fish and Wildlife Service).