Comanche Springs pupfish | |
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Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Actinopterygii |
Order: | Cyprinodontiformes |
Family: | Cyprinodontidae |
Genus: | Cyprinodon |
Species: | C. elegans |
Binomial name | |
Cyprinodon elegans S. F. Baird & Girard, 1853 | |
The Comanche Springs pupfish (Cyprinodon elegans) is a species of pupfish in the family Cyprinodontidae. [2] It is endemic to Texas, and is now found only in spring-fed pools near Balmorhea, a small town in West Texas.
Discovery and formal description of the Comanche Springs pupfish occurred in 1853. [3]
The Comanche Springs pupfish was named for the now dry Comanche Springs, an aquifer of six artesian springs in Pecos County, Texas. [4] [5]
The Comanche Springs pupfish stands out amongst cogeners due to the striking speckled color pattern of the males, as well as a more streamlined body shape and lack of vertical bars. [6] The back is relatively flat. [7] The species reaches a maximum length of around 50 mm (2.0 in). [8]
Differences also occur between members of the species from different locations in the number of fin rays and patterns of belly scales. [6]
Comanche Springs pupfish are currently found in a system of interconnected springs near Balmorhea, Texas: Phantom Lake Spring in Jeff Davis County, Texas, and San Solomon Springs, and Giffin Spring, as well as Toyah Creek, in Reeves County, Texas. [9] Base water flow for these springs comes from the Edwards-Trinity aquifer system. Additionally, runoff from the Davis Mountains recharges the overlying, alluvial aquifers. Quantity and quality of habitat respond rapidly to these recharge events. [9] Historically, these springs formed extensive marshes that likely supported large numbers of pupfish. [6] Toyah Creek is intermittent, only flowing after heavy rainfall, and as a result only occasionally provides pupfish habitat. A population formerly existed in Comanche Springs in Fort Stockton, Texas, for which the species was named. These springs went dry in 1955, resulting in the extirpation of the local pupfish population. [1] [6] Small numbers of pupfish have also been found immediately downstream of East Sandia Spring during surveys in 1993 and 2001. [9] West Sandia Spring and Saragosa Spring, though now mostly dry, likely supported the species before human modification. [6]
Most of the surviving habitat has been converted to a sixty-mile (97 km) network of interconnected concrete or earthen irrigation canals. Water flow in these canals is swift and often ephemeral, and much of the network is unsuitable for use by pupfish. [6] Because the water in the canals is sometimes diverted, resulting in mortalities, the canals are not considered permanent habitat, but rather serve as connections between larger populations in the springs. [9]
Low water levels in the aquifer have greatly reduced flow from Phantom Lake Spring, which led to the drying of the canals and reduction of pupfish habitat to a single pool at the cave from which the spring flows. As a result, the U.S. Fish and Wildlife Service filled in the old canals and constructed a more natural ciénega at the cave mouth. A pumping system was put in place to maintain water levels, and an alarm alerts authorities to failures in the pump system. [9]
Artificial refugia for the species have also been constructed at Balmorhea State Park, which contains San Solomon spring. The entire head of this spring was converted into a concrete-lined swimming pool by the Civilian Conservation Corps in the 1930s, destroying the natural ciénega. [9] The first refugium, a 275-metre (902 ft) long concrete-lined canal curving around the park motel, was completed in 1975. [7] 1996 saw the addition of a 2.5 ha (6.2 acres) ciénega within the grounds of the park, designed to replicate the appearance and functionality of the original. This wetland now contains the largest known concentrations of Comanche Springs pupfish. Finally, from 2009 to 2010, a second small ciénega was built adjacent to the 1975 canal in order to replace the older, deteriorating structure. [9]
This fish prefers water temperatures between 20-30 °C, and cannot survive above 40 °C. [9] It occurs in water with lower salinity than that occupied by other pupfish species within the Pecos River system, suggesting a long interval of isolation. [10]
The diet of adult Comanche Springs pupfish consists mostly of filamentous algae as well as some snails, [9] while juveniles subsist solely on infusoria until they grow larger. [7]
Comanche Springs pupfish spawn year-round in spring outflows and small pools. [9] Females reach sexual maturity at 5 months of age. [9] Males use visual cues to identify and establish a territory. They select sites over algal mats in swift-moving water. Males take a position upstream of their territory thus allowing them to use the current to make high-speed attacks on intruders. [7] Females will enter the territory from downstream and select a breeding site on the algal mat. [7] The female lays her eggs singly, up to 30 a day, onto the algal mat or rock. The male aggressively guards the eggs until hatching. Less dominant, average-sized males occupy the periphery of the larger male territories, while the smallest males, known as sneaker males, mimic the coloration of females in order to access eggs in the territories of dominant males without provoking an attack. [9] Breeding behavior is similar in slow-moving water except that the territories are centered around a convenient landmark such as a rock or patch of plants. [7]
Eggs average around 1.5 mm (0.059 in) in diameter, and hatch within 5 days at 20 °C. Newly hatched fry retain a relatively large yolk sack. Growth is rapid, and sexual maturity is reached at 5 months. [7]
Most Comanche Springs pupfish live for roughly one year. [9]
The Comanche Springs pupfish is included on the IUCN Red List of endangered species [1] and was federally listed as endangered by the U.S. Government in 1967. [9] [7] Threats to this species include loss of habitat due to human alteration, reduced spring flows due to high levels of water mining, and competition from introduced species. [7]
Modification of the Balmorhea area spring system starting in 1875 destroyed most of the natural marsh and stream habitat. Construction of irrigation canals diverted water into agricultural fields, leading to the drying out of marshy areas and increasing the speed at which water left the spring area. [6]
In addition to Comanche Springs, the type locale for this species, a number of other springs in the area have gone dry as a result of the pumping of irrigation water from the aquifer, demonstrating the vulnerability of the remaining springs to desiccation. [11] It is possible that continued pumping from deep-lying aquifers could eventually cause the entire Balmorhea spring system to dry up. [6]
Historic stocking of black bass species into the irrigation canals of the Phantom Cave Spring system likely severely impacted that population of pupfish. [7] The introduction of another Cyprinodon species, the sheepshead minnow, into Lake Balmorhea has resulted in a hybrid zone where the two species interbreed in the lower reaches of the Phantom Cave irrigation canals. [7] One study [12] found that when these hybrid offspring mated with Comanche Springs pupfish the resulting backcrossed offspring had lower fitness than those resulting from matings with sheepshead minnows, which could potentially result in extinction of the Comanche Springs pupfish through hybridization. As of 2013, physical barriers have prevented the sheepshead minnow from spreading further upstream in the spring system. [9]
Captive breeding stocks of the Comanche Springs pupfish are maintained at the Southwestern Native Aquatic Resources and Recovery Center (SNARRC) in Dexter, New Mexico, and the Uvalde National Fish Hatchery in Uvalde County, Texas. The Uvalde population is derived from individuals taken from the morphologically distinct Phantom Lake Spring subpopulation. In 2013, the total stock at the two facilities was 17,500 individuals. [9] These stocks provide fish that can be used to replenish natural populations in the event of a catastrophic loss. Additionally, researchers can draw from the captive stocks instead of collecting wild fish. [6]
The Comanche Springs pupfish is further at risk simply due to the susceptibility of the small population to random catastrophic loss, such as a natural disaster. The risk of extinction for any one species is known to be strongly indirectly correlated to its population size. [9]
The Death Valley pupfish, also known as Salt Creek pupfish, is a small species of fish in the family Cyprinodontidae found only in Death Valley National Park, California, United States. There are two recognized subspecies: C. s. salinus and C. s. milleri. The Death Valley pupfish is endemic to two small, isolated locations and currently classified as endangered.
The Tecopa pupfish is an extinct subspecies of the Amargosa pupfish. The small, heat-tolerant pupfish was endemic to the outflows of a pair of hot springs in the Mojave Desert of Inyo County, California. Habitat modifications, the introduction of non-native species and hybridization with the related Amargosa River pupfish led to its extinction around 1979.
The Shoshone pupfish is a subspecies of Cyprinodon nevadensis from California in the United States. It is characterized by large scales and a "slab-sided," narrow, slender body, with the arch of the ventral contour much less pronounced than the dorsal. It also has fewer pelvic fin rays and scales than the other subspecies of C. nevadensis.
The Devils Hole pupfish is a critically endangered species of the family Cyprinodontidae (pupfishes) found only in Devils Hole, a water-filled cavern in the US state of Nevada. It was first described as a species in 1930 and is most closely related to C. nevadensis and the Death Valley pupfish. The age of the species is unknown, with differing analyses offering ranges between one thousand and sixty thousand years. It is a small fish, with maximum lengths of up to 30 mm (1.2 in). Individuals vary in coloration based on age and sex: males are bright metallic blue while females and juveniles are more yellow. A defining trait of this species is its lack of pelvic fins. The pupfish consumes nearly every available food resource at Devils Hole, including beetles, snails, algae, and freshwater crustaceans, with diet varying throughout the year. It is preyed on by the predaceous diving beetle species Neoclypeodytes cinctellus, which was first observed in Devils Hole in 1999 or 2000. Reproduction occurs year-round, with spikes in the spring and fall. Females produce few eggs and the survivorship from egg to adult is low. Individuals live 10–14 months.
Cyprinodon is a genus of pupfishes found in waters that range from fresh to hypersaline. The genus is primarily found in Mexico, the Caribbean Islands and southern United States, but C. variegatus occurs as far north as Massachusetts and along the entire Gulf of Mexico coastline, and C. dearborni and C. variegatus are found in northern South America. Many species have tiny ranges and are highly threatened, in some cases already extinct. Cyprinodon are small; the largest reaches 10 cm (3.9 in) in length and most other species only reach about half that size.
The sheepshead minnow, also known as sheepshead pupfish, is a species of ray-finned fish in the family Cyprinodontidae, the pupfishes. It is found in salt marsh and estuary environments and is native to the eastern coasts of North and Central America.
Potosi pupfish is a species of fish in the family Cyprinodontidae. It is endemic to Mexico, but is now extinct in the wild, only surviving in captivity.
Bolson pupfish is a species of freshwater fish in the family Cyprinodontidae.
Cuatro Cienegas pupfish is a species of fish in the Cyprinodon genus of the family Cyprinodontidae.
The Leon Springs pupfish is a species of fish in the family Cyprinodontidae. It is endemic to Pecos County, Texas in the United States. It is a federally listed endangered species.
Cyprinodon ceciliae is an extinct species of pupfish. It was endemic to the Ojo de Agua la Presa in southwestern Nuevo Leon state in Mexico, but disappeared in 1990 due to habitat loss. The same freshwater spring system was the home of three other pupfish: Cyprinodon inmemoriam (extinct), Cyprinodon longidorsalis and Cyprinodon veronicae. Although these were from the same spring system, each was restricted to its own individual spring and associated waters. The exact spring and associated waters inhabited by the Villa Lopez pupfish were also the home of a now-extinct, undescribed species of Cambarellus crayfish. The specific name honours the daughter of María de Lourdes Lozano-Vilano and niece of Salvador Contreras-Balderas, Cecilia Contreras Lozano, who assisted on the trip on which the type was collected.
The Cachorrito de la Trinidad, also known in English as the Charco Azul pupfish, was a small species of fish in the family Cyprinodontidae. It was endemic to Ojo de Agua la Presa in southwestern Nuevo Leon state in Mexico, but became extinct in 1985 due to habitat loss. The same freshwater spring system was the home of three other pupfish: Cyprinodon ceciliae (extinct), Cyprinodon longidorsalis and Cyprinodon veronicae. Although these were from the same spring system, each was restricted to its own individual spring pool. The spring pond inhabited by the Charco Azul pupfish was also the home of a now-extinct, undescribed species of Cambarellus crayfish. The specific name inmemoriam means "in memory" and signifies the extinction of the species due to its native spring being dried out by groundwater extraction soon after the discovery of this fish in 1983.
The Pecos pupfish is a species of pupfish in the family Cyprinodontidae. It is endemic to the Pecos River watershed in eastern New Mexico and western Texas in the United States.
The Owens pupfish is a rare species of fish in the family Cyprinodontidae, the pupfish. It is endemic to California in the United States, where it is limited to the Owens Valley. It is a federally listed endangered species of the United States. This pupfish is up to 5 centimetres long, the largest males sometimes longer. The male is blue-gray, turning bright blue during spawning. The female is greenish brown with a silvery or whitish belly.
The White Sands pupfish is a species of pupfish in the family Cyprinodontidae. It is endemic to the Tularosa Basin in southern New Mexico, in the Western United States. They are only found in two springs and two small streams in southwest New Mexico. White Sands pupfish have dark eyes and silver scales. They grow from 1+3⁄4 to 2+1⁄2 inches long. Adult males have a slight blue color.
The Catarina pupfish was a diminutive species of fish in the family Cyprinodontidae, first described in 1972. It was endemic to a spring in Nuevo León, Mexico. In an attempt of saving the rapidly declining species, some were brought into captivity in the late 1980s and early 1990s, but it proved very difficult to maintain. In 1994 it became extinct in the wild. Gradually the captive populations also perished. The last male died in 2014 and the species became extinct.
Balmorhea State Park is a 46-acre (19 ha) state park located on the San Solomon Springs in Reeves County, Texas, opened in 1968. The closest city is Balmorhea, Texas. Texas Parks and Wildlife Department manages the park. The park is open year-round, and visitation is capped at 900 people per day.
The desert pupfish is a rare species of bony fish in the family Cyprinodontidae. It is a small fish, typically less than 7.62 cm (3 in) in length. Males are generally larger than females, and have bright-blue coloration, while females and juveniles are silvery or tan. A notable attribute of the desert pupfish is their ability to survive in environments of extreme salinity, pH, and temperature, and low oxygen content. The desert pupfish mates in a characteristic fashion, wherein compatible males and females will come in contact and collectively jerk in an s-shape. Each jerk typically produces a single egg that is fertilized by the male and deposited in his territory. Breeding behavior includes aggressive arena-breeding and more docile consort-pair breeding.
The Saratoga Springs pupfish is a subspecies of the Amargosa pupfish of the family Cyprinodontidae. The native population is endemic to Saratoga Springs, a small wetland in Death Valley National Park in the United States.
The Julimes pupfish is a species of killifish in the family Cyprinodontidae. This pupfish is endemic to El Pandeño, a hot spring in Julimes, Chihuahua, Mexico, and it is adapted to life in water that reaches temperatures as high as 46 °C (114 °F). Consequently, it has been referred to as the "hottest fish in the world", although the closely related Cyprinodon pachycephalus can occur in somewhat warmer waters. Cyprinodon julimes was scientifically described in 2009 as similar to Cyprinodon eximius, but it has a bigger head, nearly one-third of its standard length.