Yaqui Catfish

Ictalurus pricei

Description

The Yaqui catfish, Ictalurus pricei, is a mediumsized catfish, with a length of 6-8 in (15-20 cm). The back is a lightly mottled brown. Sides are silvery. A reddish coloration is prominent beneath the head, and on the fins and tail. The body is profusely speckled in the young, becoming a more unicolored, dark gray to black dorsally, and white to grayish beneath. The barbels are jet black except on the immediate chin, where they are gray to whitish.

Behavior

Similar to the channel catfish, the Yaqui catfish spawns in late spring. Eggs are laid in a nest, which is constructed on the bottom and guarded by the male. He incubates the eggs by fanning away silt. Hatchlings collect in small schools that are protected by the male. This catfish feeds opportunistically on insects and larvae, crustaceans, plant matter, and detritus—almost anything that is found on the bottom of the stream.

Habitat

The Yaqui catfish inhabits large streams in areas of slow to moderate current. It feeds over mud or sandy gravel bottoms in pools and backwaters.Aquatic habitats in the region are subject to severe drying in summer and sudden flooding in the rainy season. Streams flow intermittently during the dry season, and the catfish seeks refuge in permanent, often spring-fed, pools.

Distribution

This species is endemic to the Rio Yaqui basin of southeastern Arizona, northwestern Sonora, and portions of eastern Chihuahua, Mexico. It was first collected from San Bernardino Creek in extreme southeastern Arizona. The Yaqui catfish survived in San Bernardino Creek until spring flows diminished because of groundwater pumping, and the creek dried up. Remaining habitat there was severely trampled by livestock seeking water, making it un-inhabitable. This species is considered by some to be extirpated in the United States. The U. S. Fish and Wildlife Service (FWS) has assigned the Threatened status to the species.

Contract biologists from the Arizona State University and the University of Michigan surveyed the Rio Yaqui basin in 1979 and found populations of the Yaqui catfish seriously depleted in the Mexican portion of its historic range and absent from Arizona. In 1991, it was considered imperiled in the Rio Yaqui basin due to habitat modification and hybridization with channel and blue catfish.

Yaqui catfish were captured under permit from the Mexican government in 1987 and 1990, and are being cultivated at the Dexter National Fish Hatch-ery in New Mexico in anticipation of reintroductions.

Threats

The range and numbers of the Yaqui catfish have decreased significantly because of habitat modifications, such as arroyo cutting, water diversion, dam construction, and excessive pumping of groundwater from aquifers. Many rivers in Mexico, formerly inhabited by the Yaqui catfish, have been modified into an artificially channeled canal system to support irrigation agriculture. Water quality has declined due to chemical and sewage contamination. The Yaqui catfish receives no legal protection from the Mexican government.

The Yaqui catfish appears to be interbreeding with two non-native catfish, the channel catfish (I. punctatus ) and the blue catfish (I. furcatus ), which have become established in the Rio Yaqui system. If hybridization continues, the distinctive characteristics of this species could be lost.

Conservation and Recovery

If sufficient habitat can be secured and maintained in the San Bernardino National Wildlife Refuge (Cochise County, Arizona), the catfish could be reintroduced there, using Mexican stock. Habitat at the wildlife refuge, however, is considered in jeopardy because of generally lowered water tables in the region. The U. S. Bureau of Land Management (BLM) has issued leases for geothermal resources on lands adjacent to the refuge. Biologists fear that exploration and development of these leases could cause further depletion of the underground aquifers or create channels for pollution of groundwater. The BLM will examine these threats in consultation with the FWS.

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

Hendrickson, D. A., et al. 1980. "Fishes of the Rio Yaqui Basin, Mexico and United States." Journal of the Arizona-Nevada Academy of Science 15 (3): 65-106.

Miller, R. R. 1977. "Composition of the Native Fish Fauna of the Chihuahuan Desert Region." In Transactions of the Symposium on the Biological Resources of the Chihuahuan Desert Region, edited by Wauer and Riskind. Transactions of Proceedings Series, no. 3. U. S. Department of the Interior, Washington, D.C.