Nevada Fish & Wildlife Office
Pacific Southwest Region

Desert dace
(Eremichthys acros)

Class: Actinopterygii
Order: Cypriniformes
Family: Cyprinidae
Genus: Eremichthys
Species: acros
Length: 2.4 inches
Lifespan: 1 to 3 years
Feed: omnivorous, feeding primarily on filamentous algae, diatoms, aquatic vegetation, zooplankton, snails, and aquatic insect larvae
Habitat: Desert dace occupy a variety of habitats in Soldier Meadows
 

Official Status:

Threatened
 

Life History:

Ovaries of sexually mature desert dace contain ripe eggs throughout the year, and reproduction in the wild has been documented in March, May, and November, and in April under laboratory conditions. Size at sexual maturity has not been reported in the literature; however, specimens reared in the laboratory spawned at 13 months of age.

Desert dace eggs are probably unattended and adhesive. Incubation period is unknown, but is likely relatively short (2wks or less) because of the high water temperature. Larval and juvenile desert dace likely inhabit shallow, shoreline areas of the outflow streams, sheltering among aquatic and emergent vegetation. In one impounded outflow stream, larval dace have been observed among emergent vegetation in still water less than 5 centimeters deep.

 

Distribution and Habitat:

 

This species currently inhabits eight major thermal springs and about 5km of outflow creeks in Humboldt County , Nevada . There is no recent population estimate available, however in 1977 the population was estimate at 50, 000-100,000 individuals

Springs and outflow streams are contained within an area of approximately 3,830 acres. Desert dace occupy a variety of habitats in Soldier Meadows including spring pools up to 15 meters in diameter and 3.4 meter deep; outflow streams typically less than 0.3 meter deep; alkali marsh areas with overland flow among cattails ( Typha domingensis ), hardstem bulrush ( Scirpus acutus ), and other herbaceous plants; artificial impoundments; and earthen irrigation ditches. Substrate composition in the spring pools and outflow streams is variable and includes silt, sand, pebbles, and rocks.

Fun fact:

Desert dace have the highest temperature tolerance of any minnow in western North America and occupy habitats varying in temperature from 64-104 ° F.
 

Threats:

 

Modification to spring systems in Soldier Meadows for agricultural purposes started over 100 years ago. Some spring outflow streams were permanently dewatered when flows were diverted into earthen ditches or pipes for irrigation purposes, or to leach minerals from the soil. Desert dace were left stranded in dry channels when the natural outflow streams were permanently or seasonally dewatered, and dace entering the diversions were stranded in the irrigated fields. (USFWS 1997)

Thermal springs and their outflow creeks inhabited by the desert dace occur on private lands. The local landowner has modified much of the species' habitat for livestock grazing, and diverting water away from natural channels into manmade ditches for stock watering. This is especially detrimental in spring systems were the headpool temperature exceeds 100 ° F and the species can only occupy the outflow creeks. Grazing also posses the threat of trampling and overgrazing.

Actions / Current Information:

 

  Date Title   Plan Action Status
  • 05/27/1997 Recovery Plan for the Rare Species of Soldier Meadows   View Implementation Progress
             
             
             
    Last updated: April 16, 2014