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Paiute Cutthroat Trout
(Oncorhynchus clarkii seleniris)
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| Class: |
Actinopterygii |
| Order: |
Salmoniformes |
| Family: |
Salmonidae |
| Genus: |
Oncorhynchus |
| Species: |
clarkii |
Subspecies: |
seleniris |
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| Max Length: |
10 inches |
| Weight: |
1 pound |
| Lifespan: |
Less than 5 years |
| Feed: |
Terrestrial and aquatic insects |
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Official Status: |
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Listed as Endangered on March 11, 1967 under the Endangered Species Preservation Act of 1966 and reclassified as Threatened on July 16, 1975 under the Endangered Species Act of 1973. |
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Life History: |
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Paiute cutthroat trout reach sexual maturity at the age of two years. Peak spawning activity occurs in June and July. The eggs hatch in six to eight weeks and the fry emerge from the gravel in another two to three weeks. Young-of-the-year fish rear in mainstem shoals or backwaters, and often move into intermittent tributary streams until they reach about 50 mm in length |
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Distribution and Habitat: |
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The historic distribution of the Paiute cutthroat trout is limited to 14.7 kilometers (9.1 miles) of habitat in Silver King Creek from Llewellyn Falls downstream to Silver King Canyon as well as the accessible reaches of three small named tributaries: Tamarack Creek, Tamarack Lake Creek, and the lower reaches of Coyote Valley Creek downstream of barrier falls. This watershed is entirely within the boundaries of the Humboldt-Toiyabe National Forest . Currently,  Paiute cutthroat trout are not found within its historic range.
The present distribution of Paiute cutthroat trout consists of a population in Silver King Creek above Llewellyn Falls and tributary populations in Fly Valley, Four Mile Canyon Creek, Coyote Valley, and Corral Valley creeks, and four self-sustaining, pure populations outside the native drainage in the North Fork of Cottonwood and Cabin creeks (Inyo National Forest), and Stairway and Sharktooth creeks (Sierra National Forest).
Paiute cutthroat trout life history and habitat requirements appear to be similar to those reported for other western stream-dwelling salmonids. All life stages require cool, well-oxygenated waters. Adult fish prefer stream pool habitat in low gradient meadows with undercut or overhanging banks and abundant riparian vegetation. Pools are important rearing habitat for juveniles and act as refuge areas during winter. During the winter months, trout move into pools to avoid physical damage from ice scouring and to conserve energy. As with other salmonids, suitable winter habitat may be more restrictive than summer habitat. |
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Threats: |
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The greatest threat to the species is hybridization with non-native trout. The long-term survival of the current populations is uncertain due to the small size of the drainages and populations, limited genetic diversity, and no hydrologic connections between other populations. Small isolated populations exhibit founder effects, inbreeding depression, and are extremely vulnerable to extinction. |
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Last updated:
July 19, 2008
