Golden Trout (Oncorhynchus mykiss gilberti)

Threats

Golden TroutCalifornia's state fish, the Golden trout is at risk of going the way of our state mammal, the Grizzly bear. There are three primary threats to the Golden trout. The first is the threat of non-native trout stocked into the watersheds that are home to the Golden trout which are proving to interbreed with and hybridize the species. The second is livestock grazing, and it continues to damage habitat along streams and by reducing vegetation, changing the width/depth ratio, adding sediment to the channel, and lowering the water table, all of which are vital to the survival of the species. The third is the threat posed by the predation on Golden trout by non-native species that have been introduced into the last remaining habitat of the species.  It's estimated golden trout now occupy a native range of less than 20 square miles.


Habitat

The Golden trout is native to only two streams, the South Fork of the Kern River and Golden Trout Creek, just south of Mt. Whitney in the Inyo and Sequoia National Forests.


Conservation

The Golden trout has fallen victim to the careless stocking of non-native fish and more than a century of overgrazing by cattle and sheep. The species' range, which once encompassed an estimated 450 miles of stream is today a small fraction of that historic range. The U.S. Forest Service estimates that the Golden trout is secure in only 4 percent of its native habitat, or 20 square miles out of the original 450 square miles. The California golden trout is in danger of extinction caused by hybridization and by the destruction and adverse modification of its habitat. In addition, the regulatory mechanisms of the federal and state agencies responsible for managing California Golden trout habitat and preventing further loss of its genetic integrity have not to been sufficient to prevent extinction.

In 2006, The Golden Trout Project was initiated and is a collaboration between state and federal agencies, and conservation organization and takes a four-pronged approach to working towards protecting and restore the Golden trout in its native habitat. The concepts identified and followed by the Project are: locating and identifying Golden trout populations throughout the Sierra; removing non-native and predatory fish from Golden trout waters; restoring riparian habitat that has been damaged by cattle grazing; and public education and outreach. Beginning last summer, volunteer fly fishermen from throughout the state were trained in genetic sampling. Anglers are then sent to lakes and streams where golden trout are known to have been transplanted, catch a sample of 40 fish and remove a portion of their tail fins before releasing them back into the wild. DNA testing will determine the genetic purity of these populations and help scientists determine what the true impact of hybridization has been on the species.


Status

In 1991 the Golden trout was added to the U.S. Fish and Wildlife Service’s list of species as a candidate for listing under the Endangered Species Act. Following a decade of continued decline, in 2000, Trout Unlimited petitioned the U.S. Fish and Wildlife Service to list the California Golden trout as endangered under the Endangered Species Act. After not acting on the petition for close to two years, while a response within one year is mandated, action Trout Unlimited gave a 60-day notice of intent to sue and subsequently a federal judge ordered Fish and Wildlife to make a determination on the petition. The Service finally determined that that listing the species as endangered was warranted but they have still not acted upon that statement.  The most recent change to the status of the Golden trout has been by the Forest Service which added the species to its Sensitive Species List.


Scientific Research

Knapp, R.A., V.T. Vredenburg, and K.R. Matthews. 1998. Effects of Stream Channel Morphology on Golden Trout Spawning Habitat and Population Structure. Ecological Applications 8(4) 1104-1117. (278KB PDF)

Knapp, R.A. and K.R. Matthews. 1996. Livestock Grazing, Golden Trout, and Streams in the Golden Trout Wilderness, California: Impacts and Management Implications. North American Journal of Fisheries Management 16, 805-820. (1.76MB PDF)

Matthews, K.R. 1996. Habitat Selection and Movement Patterns of California Golden Trout in Degraded and Recovering Stream Sections Within the Golden Trout Wilderness, California. North American Journal of Fisheries Management 16, 579-590. (1.23MB PDF)

Matthews, K.R. 1996. Diel Movement and Habitat Use of California Golden Trout in the Golden Trout Wilderness, California. Transactions of the American Fisheries Society 125, 78-86. (762KB PDF)


Supporting Resources

2004 Conservation Assessment and Strategy for the California Golden Trout (Oncorhynchus mykiss aguabonita)Tulare County, California (2.5MB PDF)

2002 finding by USFWS of warranted status (URL)


Return to Top