Lahontan cutthroat trout (Oncorhynchus clarkii henshawi)
Taxonomy:
View taxonomy in ITISListing Status: Threatened
Where Listed: WHEREVER FOUND
General Information
Lahontan cutthroat trout (Oncorhynchus clarkii henshawi) is one of 14 cutthroat trout subspecies. They are typically dull in coloration but may have reddish hues on the sides and cheeks. Larger specimens may also have an olive-colored back with red sides and a silver belly while smaller specimens tend to be olive and yellowish on the back and sides. An orange cutthroat slash is usually present, but yellow variations occur. This subspecies can be distinguished from other cutthroat trout by the pattern of medium-large, rounded spots, somewhat evenly distributed over the sides of the body, on the head, and often on the abdomen, the highest number of gillrakers found in any trout (21 to 28), and a high number of pyloric caeca (40 to 75 or more).The species historical range included California, Nevada, Oregon, Utah. See below for information about where the species is known or believed to occur.
» Range Information
Current Range
Current range maps are only shown within the jurisdictional boundaries of the United States of America. The species may also occur outside this region.
Wherever found
Listing status: Threatened
- States/US Territories in which this population is known to or is believed to occur: California, Nevada, Oregon, Utah
- US Counties in which this population is known to or is believed to occur: View All
- USFWS Refuges in which this population is known to occur: Sheldon National Wildlife Refuge
» Candidate Information
No Candidate information available for this species.
No Candidate Assessments available for this species.
No Candidate Notice of Review Documents currently available for this species.
No Uplisting Documents currently available for this species.
» Federal Register Documents
» Species Status Assessments (SSAs)
No Species Status Assessments (SSA's) are currently available for this species.
» Recovery
- Species with Recovery Documents Data Explorer
- Recovery Priority Number: 9
No Delisting Documents currently available for this species.
» Critical Habitat
No Critical Habitat Documents currently available for this species.
» Conservation Plans
» Petitions
» Biological Opinions
To see all FWS Issued Biological Opinions please visit the BO Report.
» Life History
Habitat Requirements
Specific habitat requirements for cutthroat trout are described in Hickman and Raleigh (1982, pp. 3-7) and summarized below. Optimal stream habitat is characterized by clear, cold water with silt-free substrate and a 1:1 pool-riffle ratio. Streams should have a variety of habitats including areas with slow deep water, abundant instream cover (i.e., large woody debris, boulders, undercut banks), and relatively stable streamflow and temperature regimes. Streambanks should be well vegetated to provide cover, shade, and bank stabilization. Lacustrine LCT populations have adapted to a wide variety of lake habitats from oligotrophic (with low nutrient levels and primary productivity) alpine lakes (e.g., Independence Lake) to large, productive desert terminal lakes (e.g., Pyramid Lake). Unlike most freshwater fish species, LCT have been reported to tolerate alkalinity and total dissolved solid levels as high as 3,000 milligrams/liter (mg/L) (3,000 parts per million (ppm)) and 10,000 mg/L (10,000 ppm), respectively (Dickerson and Vinyard 1999a, pp. 510-514).
Food Habits
Stream-resident LCT are opportunistic feeders, with diets consisting of drift organisms, typically terrestrial and aquatic insects (Moyle 2002, p. 290; Dunham et al. 2000, p. 308). Recent literature has documented the importance of terrestrial insects in the diet of stream salmonids (Baxter et al. 2005, pp. 201-214). In lakes, small LCT feed largely on insects and zooplankton (Calhoun 1942, pp. 197-199; McAfee 1966, p. 228; Lea 1968, pp. 59-63), and larger LCT become piscivorous. In Pyramid Lake, fish enter the diet when LCT reach 200 mm (7.9 in) in length, comprise over 50 percent of the diet at 300 mm (11.8 in), and represent almost 100 percent of the diet when LCT are over 500 mm (19.7 in) (Sigler et al. 1983, p. 16).
Movement / Home Range
Western Lahontan basin cutthroat trout population segment are found within the Truckee River basin, Carson River basin, Walker River basin, and Honey Lake basin. Northwestern Lahontan basin population segment are found within the Quinn River/Black Rock Desert basin and Coyote Lake basin. The Humboldt River Basin population segment is found within the Humboldt River basin. There are also populations existing outside of the Lahontan basin where fish were introduced for recreational fishing purposes.
Reproductive Strategy
Lahontan cutthroat trout inhabit lakes and streams, but are obligatory stream spawners. Distance traveled to spawning sites varies with stream size and strain of LCT (strain refers to locally adapted populations in a particular area or environment). Populations in Pyramid and Winnemucca Lakes migrated as far as 160 kilometers (km) (100 miles (mi)) up the Truckee River into Lake Tahoe and its tributary streams (Sumner 1940, p. 217; Peacock and Kirchoff 2007, pp. 74-75). Small, intermittent, tributary streams and headwater reaches are sometimes used as spawning sites (Coffin 1981, p. 31). Spawning generally occurs from April through July, depending upon stream flow, elevation, and water temperature (McAfee 1966, p. 227; Lea 1968, pp. 68-69; Moyle 2002, p. 291; Rissler et al. 2006, pp. 13-15). LCT in fluvial environments generally become sexually mature around year three (Ray et al. 2007, p. 40) while LCT in lacustrine environments become sexually mature between 3 and 4 years of age (Rissler et al. 2006, p. 35). The Pilot Peak broodstock, derived from the Pilot Peak range in Utah and now known to have originated from the Truckee River watershed, sexually matures between 3 and 4 years with less than 10 percent maturing at age 5 and above (Jay Bigelow 2009, personal communication).
» Other Resources
NatureServe Explorer Species Reports-- NatureServe Explorer is a source for authoritative conservation information on more than 50,000 plants, animals and ecological communtities of the U.S and Canada. NatureServe Explorer provides in-depth information on rare and endangered species, but includes common plants and animals too. NatureServe Explorer is a product of NatureServe in collaboration with the Natural Heritage Network.
ITIS Reports-- ITIS (the Integrated Taxonomic Information System) is a source for authoritative taxonomic information on plants, animals, fungi, and microbes of North America and the world.
FWS Digital Media Library -- The U.S. Fish and Wildlife Service's National Digital Library is a searchable collection of selected images, historical artifacts, audio clips, publications, and video." +
