Tecopa pupfish
Encyclopedia
The Tecopa pupfish is an extinct
subspecies of the Amargosa pupfish (Cyprinodon nevadensis
). The small, heat-tolerant pupfish
was endemic to the outflows of a pair of hot spring
s in the Mojave Desert
of California
. Habitat modifications and the introduction of non-native species led to its extinction in about 1970.
(pupfish) of the family Cyprinodontidae
(killifish). Most divergence
of local Cyprinodon species likely took place during the early-to-mid Pleistocene
, a time when pluvial lake
s intermittently filled the now-desert region, though some may have occurred during the last 10,000 years. The evaporation of the lakes resulted in the geographic isolation of small Cyprinodon populations in remnant wetlands and the speciation
of C. nevadensis.
C. n. calidae was first described as a subspecies in 1948 by Robert Rush Miller
, after six years of study. Miller also identified five other subspecies: the Amargosa River pupfish (C. n. amargosae), the Ash Meadows pupfish (C. n. mionectes), the Saratoga Springs pupfish
(C. n. nevadensis), the Warm Springs pupfish (C. n. pectoralis), and the Shoshone pupfish
(C. n. shoshone).
Other local Cyprinodons include the Death Valley pupfish
(Cyprinodon salinus), the Devil's Hole pupfish
, (Cyprinodon diabolis) the desert pupfish (Cyprinodon macularius
) and the Owens pupfish
(Cyprinodon radiosus).
was positioned closer to the tail than the head. The pelvic fin was small or sometimes absent, and had six lepidotrichia. Similar to some other Cyprinodons, breeding males displayed a bright blue coloration. Females had between six and ten vertical stripes.
C. n. calidae primarily ate cyanobacteria (blue-green algae). Invertebrates such as mosquito larvae provided occasional nutrition. The fish were capable of surviving water temperatures of 110 degrees Fahrenheit (33 °C) or more.
in Inyo County, California
. The outflows of the two hot spring
s are tributaries of the Amargosa River
, and were the only place where C. n. calidae existed.
The popularity of the springs in the 1950s and 1960s led to the extensive alteration of the pupfishes' habitat. During the construction of bathhouses, the hot spring pools were enlarged and the outflows diverted. In 1965, the outflows of the northern and southern hot springs were re-channeled and merged. The resulting swifter currents caused downstream water temperatures to rise above a level to which the pupfish were adapted. Modifications also allowed the related Amargosa River pupfish (C. n. amargosae) to migrate upstream from the Amargosa River and hybridize with the Tecopa pupfish.
In 1966, Miller found that the population at Tecopa Hot Springs was nearly extinct. A population was found at a reservoir at a nearby motel two years later, but its smaller scales suggested that it may have already hybridized with the Amargosa River pupfish. In 1970, concerns over this habitat alteration and the presence of non-native species such as the bluegill
and the western mosquitofish led to its inclusion in both Federal and California lists of endangered species.
The last confirmed specimens of C. n. calidae were collected on February 2, 1970, and the subspecies was probably extinct by the next year. Further surveys in 1972 and 1977 returned no examples of the fish. In 1978, United States Fish and Wildlife Service
announced that it was considering delisting the fish, with Assistant Secretary of the Interior
Robert L. Herbst calling the loss "totally avoidable" and saying, "The human projects which so disrupted its habitat, if carefully planned, could have ensured its survival." In 1981, after an exhaustive search of over 40 locations, the Fish and Wildlife Service officially declared the fish extinct. It was the first animal removed from the provisions of the 1973 Endangered Species Act
as a result of its extinction.
Extinction
In biology and ecology, extinction is the end of an organism or of a group of organisms , normally a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and recover may have been lost before this point...
subspecies of the Amargosa pupfish (Cyprinodon nevadensis
Cyprinodon nevadensis
Cyprinodon nevadensis is a species of pupfish in the genus Cyprinodon. The species is also known as the Amargosa pupfish, but that name may also refer to one subspecies, Cyprinodon nevadensis amargosae...
). The small, heat-tolerant pupfish
Pupfish
Pupfish are a group of small killifish belonging to ten genera of the family Cyprinodontidae of ray-finned fish. All pupfish are especially noted for being found in extreme and isolated situations, in various parts of North America, South America, and the Caribbean region...
was endemic to the outflows of a pair of hot spring
Hot spring
A hot spring is a spring that is produced by the emergence of geothermally heated groundwater from the Earth's crust. There are geothermal hot springs in many locations all over the crust of the earth.-Definitions:...
s in the Mojave Desert
Mojave Desert
The Mojave Desert occupies a significant portion of southeastern California and smaller parts of central California, southern Nevada, southwestern Utah and northwestern Arizona, in the United States...
of California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...
. Habitat modifications and the introduction of non-native species led to its extinction in about 1970.
Taxonomy
The Tecopa pupfish is member of the genus CyprinodonCyprinodon
Cyprinodon is a genus of small killifish belonging to the family Cyprinodontidae of ray-finned fish.-Species:* Whitefin pupfish, Cyprinodon albivelis Minckley & Miller, 2002.* Potosi pupfish, Cyprinodon alvarezi Miller, 1976....
(pupfish) of the family Cyprinodontidae
Pupfish
Pupfish are a group of small killifish belonging to ten genera of the family Cyprinodontidae of ray-finned fish. All pupfish are especially noted for being found in extreme and isolated situations, in various parts of North America, South America, and the Caribbean region...
(killifish). Most divergence
Divergent evolution
Divergent evolution is the accumulation of differences between groups which can lead to the formation of new species, usually a result of diffusion of the same species to different and isolated environments which blocks the gene flow among the distinct populations allowing differentiated fixation...
of local Cyprinodon species likely took place during the early-to-mid Pleistocene
Pleistocene
The Pleistocene is the epoch from 2,588,000 to 11,700 years BP that spans the world's recent period of repeated glaciations. The name pleistocene is derived from the Greek and ....
, a time when pluvial lake
Pluvial lake
A pluvial lake is a landlocked basin which fills with rainwater during times of glaciation, when precipitation is higher. Pluvial lakes that have since evaporated and dried out may also be referred to as paleolakes.-Geology:...
s intermittently filled the now-desert region, though some may have occurred during the last 10,000 years. The evaporation of the lakes resulted in the geographic isolation of small Cyprinodon populations in remnant wetlands and the speciation
Speciation
Speciation is the evolutionary process by which new biological species arise. The biologist Orator F. Cook seems to have been the first to coin the term 'speciation' for the splitting of lineages or 'cladogenesis,' as opposed to 'anagenesis' or 'phyletic evolution' occurring within lineages...
of C. nevadensis.
C. n. calidae was first described as a subspecies in 1948 by Robert Rush Miller
Robert Rush Miller
Robert Rush Miller "was an important figure in American ichthyology and conservation from 1940 to the 1990s."...
, after six years of study. Miller also identified five other subspecies: the Amargosa River pupfish (C. n. amargosae), the Ash Meadows pupfish (C. n. mionectes), the Saratoga Springs pupfish
Saratoga Springs pupfish
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.-Taxonomy:The pupfish is a member of the genus Cyprinodon...
(C. n. nevadensis), the Warm Springs pupfish (C. n. pectoralis), and the Shoshone pupfish
Shoshone pupfish
The Shoshone pupfish, Cyprinodon nevadensis shoshone, 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...
(C. n. shoshone).
Other local Cyprinodons include the Death Valley pupfish
Death Valley pupfish
The Death Valley pupfish, Cyprinodon salinus salinus, is found in Death Valley National Park.-Description:The Death Valley pupfish is a species of fish that is the last known survivor of what is thought to have been a large ecosystem of fish species that lived in Lake Manly, which dried up at the...
(Cyprinodon salinus), the Devil's Hole pupfish
Devil's Hole pupfish
The Devil's Hole pupfish, Cyprinodon diabolis, is a species of fish native to Devil's Hole, a geothermal , aquifer-fed pool within a limestone cavern, in the Amargosa Pupfish Station of the Desert National Wildlife Refuge Complex east of Death Valley National Park.-Physical description:The Devil's...
, (Cyprinodon diabolis) the desert pupfish (Cyprinodon macularius
Cyprinodon macularius
Cyprinodon macularius is a rare species of fish in the family Cyprinodontidae and is known by the common name desert pupfish. It is a federally listed endangered species in the United States....
) and the Owens pupfish
Owens pupfish
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 long, the largest males...
(Cyprinodon radiosus).
Description and behavior
The fish were about 1–1.5 inches (2.5–4 cm) in length. The dorsal finDorsal fin
A dorsal fin is a fin located on the backs of various unrelated marine and freshwater vertebrates, including most fishes, marine mammals , and the ichthyosaurs...
was positioned closer to the tail than the head. The pelvic fin was small or sometimes absent, and had six lepidotrichia. Similar to some other Cyprinodons, breeding males displayed a bright blue coloration. Females had between six and ten vertical stripes.
C. n. calidae primarily ate cyanobacteria (blue-green algae). Invertebrates such as mosquito larvae provided occasional nutrition. The fish were capable of surviving water temperatures of 110 degrees Fahrenheit (33 °C) or more.
Decline and extinction
Tecopa Hot Springs lies at an elevation of 1,411 feet (430 m), about 2 miles north of the town of TecopaTecopa, California
Tecopa is a census-designated place in the Mojave Desert, in Inyo County, California, United States. Tecopa is located south-southeast of Shoshone, at an elevation of . The population was 150 at the 2010 census, up from 99 at the 2000 census.One of Tecopa's popular features is its natural hot...
in Inyo County, California
Inyo County, California
-National protected areas:* Death Valley National Park * Inyo National Forest * Manzanar National Historic Site-Major highways:* U.S. Route 6* U.S. Route 395* State Route 127* State Route 136* State Route 168* State Route 178...
. The outflows of the two hot spring
Hot spring
A hot spring is a spring that is produced by the emergence of geothermally heated groundwater from the Earth's crust. There are geothermal hot springs in many locations all over the crust of the earth.-Definitions:...
s are tributaries of the Amargosa River
Amargosa River
The Amargosa River is an intermittent waterway, long, in southern Nevada and eastern California in the United States. It drains a high desert region, the Amargosa Valley in the Amargosa Desert northwest of Las Vegas, into the Mojave Desert, and finally into Death Valley where it disappears into...
, and were the only place where C. n. calidae existed.
The popularity of the springs in the 1950s and 1960s led to the extensive alteration of the pupfishes' habitat. During the construction of bathhouses, the hot spring pools were enlarged and the outflows diverted. In 1965, the outflows of the northern and southern hot springs were re-channeled and merged. The resulting swifter currents caused downstream water temperatures to rise above a level to which the pupfish were adapted. Modifications also allowed the related Amargosa River pupfish (C. n. amargosae) to migrate upstream from the Amargosa River and hybridize with the Tecopa pupfish.
In 1966, Miller found that the population at Tecopa Hot Springs was nearly extinct. A population was found at a reservoir at a nearby motel two years later, but its smaller scales suggested that it may have already hybridized with the Amargosa River pupfish. In 1970, concerns over this habitat alteration and the presence of non-native species such as the bluegill
Bluegill
The Bluegill is a species of freshwater fish sometimes referred to as bream, brim, or copper nose. It is a member of the sunfish family Centrarchidae of the order Perciformes.-Range and distribution:...
and the western mosquitofish led to its inclusion in both Federal and California lists of endangered species.
The last confirmed specimens of C. n. calidae were collected on February 2, 1970, and the subspecies was probably extinct by the next year. Further surveys in 1972 and 1977 returned no examples of the fish. In 1978, United States Fish and Wildlife Service
United States Fish and Wildlife Service
The United States Fish and Wildlife Service is a federal government agency within the United States Department of the Interior dedicated to the management of fish, wildlife, and natural habitats...
announced that it was considering delisting the fish, with Assistant Secretary of the Interior
United States Secretary of the Interior
The United States Secretary of the Interior is the head of the United States Department of the Interior.The US Department of the Interior should not be confused with the concept of Ministries of the Interior as used in other countries...
Robert L. Herbst calling the loss "totally avoidable" and saying, "The human projects which so disrupted its habitat, if carefully planned, could have ensured its survival." In 1981, after an exhaustive search of over 40 locations, the Fish and Wildlife Service officially declared the fish extinct. It was the first animal removed from the provisions of the 1973 Endangered Species Act
Endangered Species Act
The Endangered Species Act of 1973 is one of the dozens of United States environmental laws passed in the 1970s. Signed into law by President Richard Nixon on December 28, 1973, it was designed to protect critically imperiled species from extinction as a "consequence of economic growth and...
as a result of its extinction.