Pecos Bluntnose Shiner

Notropis simus pecosensis

Description

Pecos bluntnose shiner (Notropis simus pecosensis ) is a small minnow, reaching an adult length of up to 3.5 in (8.9 cm). It has a slender, silvery body and a large mouth overhung by a bluntly rounded snout. This shiner was first thought to be part of a single species (Notropis simus ), whose range extended throughout the Rio Grande river basin. In 1982 biologists determined that the species was made up of two subspecies—Rio Grande (N. s. simus ) and Pecos (N. s. pecosensis ). The Rio Grande subspecies, once commonly used as a baitfish, has not been collected since 1964 and is believed extinct.

Behavior

Little information on the life history of this species is available. It is thought to feed mostly on terrestrial and aquatic insects, augmented with algae and plant matter. It probably spawns from spring to autumn.

Habitat

Pecos bluntnose shiner inhabits the main channel of the Pecos River, a slow-flowing, shallow (16 in [41 cm]) river with a sandy bottom. Younger fish have been found in backwaters, riffles, and pools. Natural springs such as those in the Santa Rosa and Lake McMillan areas also support small populations.

Distribution

This subspecies was first collected in 1874 from the Rio Grande near San Ildefonso, New Mexico. It was subsequently found in the Pecos River between Santa Rosa and Carlsbad.

Pecos bluntnose shiner occurs in the Pecos River (in New Mexico) in two river segments totaling some 100 mi (161 km). The first segment extends from approximately 10 mi (16 km) south of Fort Sumner downstream about 64 mi (103 km) into Chaves County; the second, shorter, segment of about 37 mi (60 km) stretches between Hagerman and Artesia in Chaves and Eddy counties.

Within these two stretches, abundance of the species is uneven. The largest populations occur in seepage areas of the river upstream from Highway 70 crossing to Fort Sumner, and, to a lesser extent, in the reach between Hagerman and Artesia.

The species is now far less common than it once was. A 1982 survey netted only 76 specimens, compared with 818 in 1941 and 1,482 in 1939. Collections made in 1986 at five historic sites contained a total of 131 Pecos bluntnose shiners. Additional collections have been made systematically since that time and have shown varying degrees of population decline and recovery.

The waters of the Pecos River are administered by the states of New Mexico and Texas through the Pecos River Compact. The Bureau of Reclamation and the Army Corps of Engineers operate dams on the river in accordance with the compact. Land along the Pecos River is mostly privately owned. Federal land includes a few small parcels between Fort Sumner and Roswell, administered by the Bureau of Land Management. A short section of the river flows through the Bitter Lakes National Wildlife Refuge.

Threats

Though very little is known about the reasons for the species' decline, it seems apparent that the cause is related to, if not exclusively the result of, habitat modifications. Changes to Pecos bluntnose shiner's environment since the mid-1980s include the habitat's physical alteration, its pollution, and the introduction of non-native species. This is part of a general pattern of decline in small, short-lived fishes that are native to the large riverine waters of the Southwest.

The U. S. Fish and Wildlife Service (FWS) has expressed concern over the status of this shiner since 1978, when it was determined that the waterflows in the Rio Grande and Pecos rivers had been greatly reduced by dam construction and diversion of water for irrigation. The FWS believed for a time that Pecos bluntnose shiner was already extinct. Efforts to list the fish as endangered were stalled until specimens were rediscovered in New Mexico.

Conservation and Recovery

The FWS has designated two sections of the Pecos River in New Mexico as critical for the survival of the Pecos bluntnose shiner: 1) 64 mi (103 km) from Fort Sumner downstream into Chaves County and 2) 37 mi (59.5 km) between Hagerman and Artesia. Both areas support relatively abundant, reproducing populations of the shiner, but flow in the river below Fort Sumner could be radically reduced by further dam construction.

In the 1980s the New Mexico Parks and Recreation Commission was granted a permit to establish a permanent recreation pool in Santa Rosa Reservoir that would reduce flows below Alamogordo Reservoir. Construction on the Brantley Dam in that area commenced in 1983. The Pecos River is already highly managed, with dams and diversion structures along most of its course. Most structures on the river have been built by the Army Corps of Engineers, which has stated that future flood control measures can be managed to preserve Pecos bluntnose shiner.

The State of New Mexico has provided some legal protection for this species through the New Mexico Wildlife Conservation Act, which prohibits taking of any listed species without a scientific collecting permit. The state also has a limited ability to protect the habitat through the Habitat Protection Act, water pollution legislation, and tangentially through a legal provision that protects areas used by game fish.

The 1992 recovery plan for the species (from the FWS) considers species' stabilization to be the primary recovery goal. Recovery criteria involve maintaining viable populations throughout the 100 mi (160.9 km) of habitat where the species still occurs. To achieve this goal, the FWS recommended 1) monitoring, maintaining, and enhancing existing populations; 2) reintroducing the fish into historic habitats; 3) enforcing statutes that protect existing populations and their habitats; and 4) developing and implementing public information programs. If stabilization is achieved, delisting objectives will be determined by the FWS in 2002.

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

Chernoff, B., R. R. Miller, and C. R. Gilbert. 1982."Notropis orca and Notropis simus, Cyprinid Fishes from the American Southwest." Occasional Papers of the Museum of Zoology, University of Michigan 698: 1-49.

New Mexico Department of Game and Fish. 1982."The Status of Notropis simus pecosensis in the Pecos River of New Mexico." Office of Endangered Species, Albuquerque.

U. S. Fish and Wildlife Service. 1987. "Determination of Threatened Status for Pecos Bluntnose Shiner." Federal Register 52: 5295-5303.

U. S. Fish and Wildlife Service. 1992. "Recovery Plan for Pecos Bluntnose Shiner." U. S. Fish and Wildlife Service, Albuquerque.