Snorkel Survey Results

A dace counter snorkels down the stream

A member of the fish count team snorkels down the Muddy River stream channels counting every fish she sees.


As of February 2020, snorkel surveys determined the current Moapa dace population consists of 1340 fish. Biologists are optimistic about the continued health of the species. The all-time low for the dace population was ten years ago, in 2008, when only 459 fish were counted. For more information on snorkel survey dace counts, check out this PDF of dace counts from 2005 until 2017.

Work is continually underway to help keep the warm springs stream system in top condition for America’s favorite fish. Cattails and vallisnaria (an aquatic grass thought to have been introduced by the dumping of unwanted aquariums in the 1960s) need to be removed regularly as part of the maintenance of the streams. Cattails and vallisnaria are both tenacious, grow rapidly, and spread easily. Streams choked with vallisneria and cattails have slower-moving water that cools and accumulates silt. Since the dace favor warm, fast-moving, clear water with sand or gravelly substrate, removal of these aquatic plants is a priority to rehabilitate the streams and give the dace their best shot at recovery. 

Work is also being done to remove smaller non-native fish, such as mollies and mosquitofish, that compete with the dace for food and habitat.

We are always looking for volunteer groups to help with stream rehabilitation projects. Please contact refuge staff if you are able to help out.

To protect the dace, continued efforts from partner agencies are essential. The Moapa Valley National Wildlife Refuge thanks the Nevada Department of Wildlife, the Southern Nevada Water Authority, the Moapa band of Paiutes, and other partners for their continued support.