Devil’s Hole pupfish

Cyprinodon diabolis

SPECIES CODE: E009 V01

STATUS:

Listed as Endangered in the entire range on March 1, 1967 (32 FR 4001).

Note: All descriptions can be found within the Recovery Plan (1980), unless otherwise noted.

SPECIES DESCRIPTION:

The Devil’s Hole pupfish is a member of the Cyprinodontidae family. This species rarely exceeds 0.98 inches, and has a life span of about one year. The species is diurnal by nature, regularly utilizing areas beyond the shallow shelf to a maximum depth of approximately 30m. The species feeds on algae, diatoms, and invertebrates.

REPRODUCTION AND DEVELOPMENT:

Not much is known about the reproductive habits of the species, except that it is able to spawn year round. Growth and development is dependent on food supply (algae).

RANGE AND POPULATION LEVEL:

This species is naturally restricted to Devil’s Hole, a limestone cave situated on the east central border of Ash Meadows, Nye County, Nevada. Small refugium populations have been established in the Amargoso Pupfish Station in Ash Meadows and in facilities constructed by the Bureau of Reclamation located near the base of Hoover Dam along the Colorado River. The species population fluctuates during the year from about 127 to 553 individuals (USFWS 1990).

HABITAT:

The spring pool of Devil’s Hole is located approximately 15 meters below the land surface where a shallow rock shelf approximately 2x4 meters is located. Just beyond the shelf, the spring descends to an unknown depth (more than 80m) into myriad of chasms, mostly unexplored.

PAST THREATS:

Water levels in Devil’s Hole are designated as distance (in feet) below a USGS datum point installed on the rock wall above maximum water level (copper washer). The Devil’s Hole pupfish population started to decline in the 1960’s due to groundwater pumping for agricultural purposes. In 1977, the U.S. District Court for the District of Nevada, entered its order that the minimum water level at Devil’s Hole necessary to preserve the pupfish is 2.7 feet below the copper washer.

CURRENT THREATS:

The main threat to the Devil’s Hole pupfish continues to be water loss. Algal growth is dependent upon the amount of sunlight reaching the shelf. Recently, sandladen runoff has removed much of the algal growth from the shelf, thus affecting food availability.

CONSERVATION MEASURES:

LITERATURE CITED:

U.S. Fish and Wildlife Service. 1980. Devil’s Hole Pupfish Recovery Plan. U.S. Fish and Wildlife Service. Portland, Oregon. 46+pp.

U.S. Fish and Wildlife Service. 1990. Recovery plan for the endangered and threatened species of Ash Meadows, Nevada. U.S. Fish and Wildlife Service, Portland, Oregon. 123 pp.