Rio Yaqui Fish Management and Protection by the U.S. Fish and Wildlife Service

Authors: William Radke

Year: 2016 (xlviii)

Abstract

San Bernardino National Wildlife Refuge and Leslie Canyon National Wildlife Refuge are located in southeast Arizona, adjacent to the international border with Mexico. The primary role of the two refuges is the sustainability and recovery of native fish in the R’o Yaqui Basin. These are two of the few refuges administered by the U.S. Fish & Wildlife Service that were created specifically to protect native fish. The refuges are along the northern margin of the R’o Yaqui basin, which begins as R’o Papigochic in Chihuahua, receives water from R’o de Bavispe in Sonora, and flows south into the Sea of Cortez near Ciudad Obregon. Most of the watershed is in Mexico, with only a small percent draining the Sulphur Springs and San Bernardino Valleys in the United States. The San Bernardino Valley once supported permanently flowing creeks, springs, and marshy wetlands. In addition, the giant sacaton grassland in the valley was once described as ‘a luxuriant meadow some eight or ten miles long and a mile wide.’ The delicate balance within the northern R’o Yaqui Basin was able to provide historic habitat for a multitude of plants and animals, including eight kinds of native fish. These are the beautiful shiner (Cyprinella formosa), Yaqui chub (Gila purpurea), Yaqui catfish (Ictalurus pricei), Yaqui topminnow (Poeciliopsis occidentalis sonoriensis), Mexican longfin dace (Agosia sp.), Mexican stoneroller (Campostoma ornatum), Mexican round-tailed chub (Gila minaceae), and Yaqui sucker (Catostomus bernardini). Six of these species were found nowhere else in the United States. The extensive wetlands here were crucial to fish survival, but depletion of the underground aquifer ultimately led to severe habitat changes and the eventual local extinction of many species. In addition, the ultimate introduction and spread of non-native fish and Asian tapeworm continue to threaten the existence of native fish populations. Fish recovery actions include stabilizing and maintaining existing populations, establishing self-sustaining populations, and restoring wetland habitat so that the fish will be able to thrive once again.