Comanche Springs Pupfish

Cyprinodon elegans

Description

Fish in the genus Cyprinodon average about 2.8 in (7 cm) in length. The Comanche Springs pupfish, C. elegans, is one of the most distinctive species of pup-fish. Both sexes are silvery brown and lack vertical bars; males exhibit a "speckled" color pattern. Two rows of lateral stripes, comprised of squarish black blotches that are tangent to but not touching each other, run from behind the head to the tail. The top edge of the upper stripe runs along the spine while the lower edge of the bottom stripe is about two-thirds down the side. The top fanlike fin and the tail fin are bluish-turquoise.

Behavior

This pupfish has not been extensively studied and little is known of its behavior. It spawns in spring outflows and in small pools of standing water. It feeds on insects and plant material in all areas of its habitat.

Habitat

The Comanche Springs pupfish prefers freshwater shallow runs with slow current. Since most other pupfishes occupy more saline waters, long isolation from other species of the genus is probable.

Distribution

The Comanche Springs pupfish was known to inhabit two isolated spring systems, 114 mi (190 km) apart, in the Pecos River drainage of southwestern Texas. The first included Comanche Springs and the headwaters (now dry) of a group of streams that presently fall within the city limits of Fort Stockton (Pecos County). Comanche Springs dried up during the 1950s, completely destroying that pupfish population. The second spring system was found near Balmorhea in Reeves County, Texas. These springs and associated marshes have been extensively modified to support an irrigation network.

The species is known to occur only in Reeves County in Giffin and San Solomon Springs, an irrigation network fed by Phantom Lake, and Toyah Creek. The water from Phantom Lake Spring is diverted by a system of earthen dams into concrete irrigation ditches. Water is directed down a canal to merge with flows from San Solomon Spring and then enters two major channels for diversion into agricultural fields. The pupfish population is locally numerous but generally sparse throughout most of the network. Fish are seen sporadically near the mouth of a concrete irrigation canal entering Lake Balmorhea. No current population estimates have been made.

Threats

Other pupfish have been introduced into the same water system and threaten the Comanche Springs pupfish in two ways: by direct competition for limited food supplies; and by possible inter-breeding and hybridization. The main threat to the Comanche Springs pupfish, however, remains the artificial conditions of water flow within its habitat. Seasonal drying can strand and kill large numbers of fish, and recovery efforts have focused on methods to moderate the extreme pattern of drying and flooding of the stream and irrigation network.

Conservation and Recovery

To support the long-term survival of the species, some means must be found to stabilize the water table in the area. Increased pumping of groundwater for agriculture and human use has lowered water levels and reduced spring flows. Large artesian springs near Balmorhea are diminishing in flow, and Phantom Lake Spring is expected to dry up within 50 years. In fact, most large springs of West Texas have measurably diminished.

The Texas Parks and Wildlife Department has constructed a refuge at Balmorhea State Recreation area to provide stable flowing water for several thousand Comanche Springs pupfish. The Dexter National Fish Hatchery in New Mexico maintains a genetic stock of the pupfish, which will be used for reintroduction if the wild population is eliminated by drought or other cause.

Contact

U. S. Fish and Wildlife Service
Regional Office, Division of Endangered Species
P. O. Box 1306
Albuquerque, New Mexico 87103-1306
Telephone: (505) 248-6911
Fax: (505) 248-6915
http://southwest.fws.gov/

References

Davis, J. R. 1979. "Die-Offs of an Endangered Pup-fish, Cyprinodon elegans (Cyprinodontidae)." Southwestern Naturalist 24: 534-536.

Hubbs, C. 1957. "Distributional Patterns of Texas Fresh-Water Fishes." Southwestern Naturalist 2: 89-104.

U.S. Fish and Wildlife Service. 1980. "Comanche Springs Pupfish (Cyprinodon elegans ) Recovery Plan." U.S. Fish and Wildlife Service, Albuquerque.