Moapa Valley National Wildlife Refuge is a 106-acre protected area in Nevada’s Warm Springs Natural Area, established in 1979 to safeguard habitat for the endangered Moapa dace in the Muddy River system. Its key habitat includes stream channels and six hot springs near the site’s center. The refuge is part of the Desert National Wildlife Refuge Complex and has become notable for both its ecological value and its fragility, as altered habitat, reduced streamflows from groundwater pumping, and introduced fish have contributed to the dace’s decline since the 1990s. Part of the refuge, the Plummer Unit, was once a resort property before being added to the refuge.