|Scientific Name:||Cyprinodon elegans|
|Species Authority:||Baird & Girard, 1853|
|Red List Category & Criteria:||Endangered B1ab(iii,v)+2ab(iii,v) ver 3.1|
|Reviewer(s):||Smith, K. & Darwall, W.R.T.|
|Facilitator/Compiler(s):||Hammerson, G.A. & Ormes, M.|
This species is listed as Endangered because its extent of occurrence is less than 100 sq km, area of occupancy is less than 10 sq km, the species occurs in just a few locations, and the species is subject to declines resulting from changes in water availability and the effects of non-native fish species.
|Range Description:||The Comanche Springs Pupfish historically occurred in two areas about 90 kilometres apart in the Pecos River drainage, Texas. One inhabited area was Comanche Springs, with its headwaters in Fort Stockton, Pecos County, Texas; this spring dried up in the 1950s and the pupfish population was extirpated. The species is still extant in the other area, a small series of springs, their outflows, and a system of irrigation canals historically interconnecting Phantom Lake Springs (located in easternmost Jeff Davis County, Texas), San Solomon Springs, Giffin Springs, and Toyah Creek near Balmorhea, Reeves County, Texas (Echelle et al. 2003).|
|Range Map:||Click here to open the map viewer and explore range.|
This species is represented by what can be regarded as one or not more than a few distinct occurrences (subpopulations).
During 1999 to 2001, the population in San Solomon Ciénega in Balmorhea State Park averaged 270,000 in summer and approximately 18,000 in winter (Garrett 2003).
Population size in the park refugium canal has been estimated to range from 968 to 6480 (see Garrett et al. 2002).
Intensive surveys of Phantom Lake Spring from 1993 to 1995 resulted in total abundance estimates of Comanche Springs Pupfish as high as nearly 400 individuals during late summer collections (Winemiller and Anderson 1997). As of 2004, the Phantom Spring outflow contained not more than 100-200 Cyprinodon elegans.
Uvalde National Fish Hatchery in Uvalde, Texas, and Dexter National Fish Hatchery and Technology Center in New Mexico maintain captive populations of several thousand individuals.
Drying of Comanche Springs resulted in loss of about half of the historical habitat.
The number of pupfish in the San Solomon Spring outflow has greatly increased in recent years as a result of increased habitat availability (Garrett 2003). San Solomon Ciénega, constructed in 1995, provided additional habitat.
Phantom Lake Spring ceased flowing during the summer of 1999 and has not recovered. Water in the small remaining pool inhabited by pupfish is provided by a pump system. In July 2004, heavy local rainfall resulted in a large flow from Phantom Lake Spring. However, flows were expected to subside and soon return to pre-rainfall conditions. Overall, Phantom Lake Spring is experiencing a long-term, consistent decline in flow (the causes of which are not well established), and prospects for the maintenance of adequate pupfish habitat there are poor.
|Habitat and Ecology:||This species inhabits freshwater springs and associated marshes and canals (USFWS 1981). This pupfish usually occurs over mud in current (Page and Burr 2011). Spawning occurs in various sites ranging from fast-flowing water (spring outflows) to standing water (USFWS 1981, Ono et al. 1983).|
|Use and Trade:||This species is no utilized.|
Comanche Springs dried up as a result of excessive groundwater pumping.
Major threats include: (1) competition with introduced species; (2) degradation of genetic integrity caused by hybridization with introduced Cyprinodon species; and (3) habitat loss from declining springflow and reduced surface waters (USFWS 1981). Groundwater pumping for agriculture and human use threatens habitat by lowering water levels and reducing spring flows. Flow reductions have been much greater at Phantom Lake Spring than at San Solomon Spring.
Cyprinodon elegans hybridizes with introduced Sheepshead Minnow (C. variegatus) (Lee et al. 1980), but Echelle and Echelle (1994) found only meagre evidence of genetic introgression after more than 20 years of secondary contact. However, a large population of Sheepshead Minnow occurs in Lake Balmorhea (Echelle and Echelle 1994), and expansion of the nonnative species into upstream areas of the spring outflows is a constant threat to the existence of the wild population of C. elegans.
Recovery efforts have focused on moderating water level fluctuations.
San Solomon Spring has a man-made refugium and cienega in Balmorhea State Park, Reeves, County, Texas (Echelle and Echelle 1994, Brannan et al. 2003). A refugium also has been constructed below Phantom Lake Spring (Young et al. 1993).
In the early 1990s, efforts were underway to determine methods to remove Cyprinodon variegatus from the spring systems, their feeder canals, and Lake Balmorhea (Minckley and Deacon 1991).
|Citation:||NatureServe 2013. Cyprinodon elegans. The IUCN Red List of Threatened Species. Version 2015.2. <www.iucnredlist.org>. Downloaded on 03 July 2015.|