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Rio Grande cutthroat trout (Oncorhynchus clarki viriginalis):

Historic range:
The historic range of the Rio Grande cutthroat trout-the state fish of New Mexico-likely encompassed all cool waters in the Rio Grande drainage, including the Chama, Jemez and Rio San Jose drainages, along with suitable waters of the Pecos and Canadian drainages.

Habitat requirements:
Like most members of the trout family, Rio Grande cutthroat trout require clear, cold water, naturally-fluctuating flows, low levels of fine sediment in channel bottoms, well-distributed pools, stable streambanks, and abundant stream cover.

Current population status:
One of North America's most beautiful fish, pure populations of the Rio Grande cutthroat trout have been reduced to fewer than 100 tiny headwater streams, occupying roughly 1% of the subspecies' historic range. Most remaining populations continue to be threatened by the factors that lead to this significant diminution of range, including competition with and predation by non-native trout, and habitat degradation related to livestock grazing, logging, roads, mining and water diversion. Because of the small size and isolation of Rio Grande cutthroat streams, most remnant populations are also vulnerable to environmental perturbations, such as drought, fire, or freezing temperatures, and problems associated with small population size, such as loss of genetic diversity and random fluctuations in population size.

Threats to persistence:
Habitat loss, caused mainly by livestock grazing, water diversions, logging, road building and urban and agricultural development, and introduction of exotic fishes are the primary causes of decline. All but the latter activities adversely affect the habitat requirements of these trout.

Listing Status (as of 02/03):
Center for Biological Diversity and a coalition of groups filed a petition to list the Rio Grande cutthroat trout as endangered in February of 1998. The U.S. Fish and Wildlife Service initially rejected the petition, but after CBD and other groups filed suit, they settled, agreeing to complete a status review by June, 2002. On June 11, 2002, Fish and Wildlife completed their status review again determining that the species does not merit listing. The Fish and Wildlife Service's finding admits the trout has been eliminated from as much as 99% of its historic range, and that most populations continue to be threatened by introduction of non-native trout, livestock grazing, logging, road building, dams, water diversions, and disease. They argue that the existence of just 13 populations with a barrier and over 2,500 individuals is sufficient to make the species safe from extinction. Even these populations, however, are not secure because they are found in tiny headwater streams subject to disturbance from drought, fire or other factors, reinvasion by non-native trout, and ongoing habitat degradation. CBD, Biodiversity Conservation Alliance, Carson Forest Watch, Center for Native Ecosystems, Pacific Rivers Council and New Mexican fisherman Michael Norte filed suit to overturn this latest finding February 25, 2003.

Note of interest: The Rio Grande cutthroat was the first North American trout ever observed by Europeans- in 1541 Pedro de Castaņedade Najera, a member of Coronado's expedition, first saw it, writing of "a little stream which abounds in excellent trout and otter" (the otter is now extinct in the Southwest) This stream was in all likelihood Glorieta Creek, southeast of present day Santa Fe, which is now a barren, ephemeral wash for most of its length probably because of a combination of livestock grazing and other impacts.

Suit filed to protect Rio Grande cutthroat trout: PRESS RELEASE

Rio Grande cutthroat trout NEGATIVE FINDING

CBD COMMENTS on Rio Grande cutthroat status