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, the Rio Grande cutthroat trout has been reduced to approximately
176 populations found in tiny headwater streams, which are
highly vulnerable to decimation by flood, drought or other
environmental changes, and occupy less than 10% of the subspecies'
historic range. Conservation populations--those with a high
degree of genetic integrity--are only found in about 3% of
the area of these trout's historic range, as documented in
the Western Native Trout Campaign's report: Imperiled
Western Trout and the Importance of Roadless Areas. This
same report indicates that approximately 39% of the remaining
conservation populations of Rio Grande cutthroat trout are
associated with roadless areas, indicating that the full protection
of roadless areas is critical to the continued persistence
of these magnificent native trout.
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 5/02): 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. Although
the U.S. Fish and Wildlife Service concurred with the petition's
finding that the Rio Grande cutthroat occupied less than 10%
of its range and continued to be threatened by many of the
factors that lead to its decline, the agency rejected the
petition issuing a negative 90-day finding. The Center for
Biological Diversity, the Biodiversity Legal Foundation, the
Rio Grande Chapter of Trout Unlimited, Carson Forest Watch,
Rio Grande Chapter of the Sierra Club, and Southwest Trout,
challenged
the decision in court and in June, 2001 reached an agreement
with the U.S. Fish & Wildlife Service to have the species'
status and need for Endangered Species Act listing be re-assessed
by June 9, 2002. The Center for Biological Diversity and Biodiversity
Associates submitted comments
(link) for this review and are hopeful for a positive decision.
Note
of interest: The Rio Grande cutthroat was the first North
American trout ever observed by Europeans- in 1541 Pedro de
Castañedade 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.
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