Colorado Squawfish
Freshwater fishes are the most imperiled vertebrate group in the United
States (Williams et al. 1989; Minckley and Deacon 1991; Warren and Burr
1994). In the United States, about 20% of fishes are extinct or imperiled,
as compared with 7% of the country's mammals and birds (Master 1990).
Almost 30% of the surface land area in the conterminous United States
occurs west of the Continental Divide, but only about 21% of the roughly
800 freshwater fishes native to the United States are found there. Aquatic
ecosystems in western North America, however, particularly in the Southwest,
are endowed with some of the highest rates of endemism
on the continent. In the Colorado River basin, for example, 35% of all
native genera and 64% of the 36 fish species are endemic (Carlson and
Muth 1989). The other southwestern watershed that demonstrates a high
degree of fish endemism (30%) is the Rio Grande in New Mexico.
Colorado Squawfish
Colorado Squawfish
Colorado Squawfish
Colorado Squawfish
Colorado Squawfish
Colorado Squawfish
Colorado Squawfish
Colorado Squawfish
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