Main Menu

ANR Fish Workgroup

Fish People

California Fish Species

Fish Search By Location

Cooperative Extension Links

California Fish Website Species Search

Inland Cutthroat Trout, Oncorhynchus clarki (Paiute & Lahontan)
		Paiute Cutthroat Trout. This photo of a Lahontan Cutthroat Trout was taken by Gerard Carmona Catot.
		Appearance and Identification: · Maximum length about 1 M TL (Lahontan), smaller coastal forms in CA max around 50 cm FL · Red slashes of pigment underneath lower law (faint in sea-run or young < 8 cm TL) · Well developed teeth on jaws, head, tongue, etc. · Many black body spots · Adipose fin may have few spots, dorsal fin may have black leading edge · Similar to rainbow trout, but Cutthroats have: o More slender body o Larger mouth o Basibranchial teeth-found on bottom of throat · Coloration of Cutthroat sub-species: o Coastal: similar to rainbow, but heavier spotting, especially in posterior and ventral halves o Lahontan: fewer larger spots than coastal form, dark olive to reddish brown body o Paiute: adults retain parr marks; body and tail lack black spots; spots present on dorsal and adipose fins; copper, green , or yellowish body · Fin rays: dorsal 9 - 11, anal 8 - 12, pelvic 9 - 10, pectoral 12 - 15 · Lateral line scales: 110 - 130
Life History:
		The inland forms of cutthroat trout were historically one of only two salmonids found on the eastern side of the Sierras. They are found in small to large rivers and lakes with common characteristics of cool water and adequate dissolved oxygen. Inland cutthroat trout have a wide degree of tolerance for temperature, sediment, and alkaline conditions. They have been found to live in streams where the temperature exceeds 27°C, and found in lakes with a TDS of 13,000 mg/L and a pH of p.9.5. Historically they were probably found in streams with abundant food sources and with a maximum water temperature of 23 °C. Inland cutthroat trout, like their coastal forms, may have varying degrees of movement or migration. A fish may spend its entire life in a 20 m reach of stream, or a cutthroat may move many kilometers within a lake or river network. In streams they feed on drifting and benthic insects, whereas in lakes their diet may also include zooplankton, crustaceans, snails and other fish. Growth rates are temperature and food dependant. The largest ever recorded Lahontan cutthroat from Pyramid Lake, NV was 99 cm TL and weighed 18.6 g. Paiute cutthroat trout, which are typically found in small high elevation streams, rarely exceed 25 cm FL. Inland cutthroat trout reach sexual maturity in 2 - 4 years. Spawning takes place in April through early July, with most Lahontan cutthroat trout moving up into tributaries of lakes and rivers to breed. Fecundity of Lahontan cutthroats is about 400 - 8,000 eggs per female, a number that grows with body size. Paiute cutthroats only produce 325 - 350 eggs per female. Lahontan cutthroat trout may spawn up to 5 times whereas Paiute cutthroat trout only spawn once in a life time. Maximum expected ages are 9 years and 3 years, respectively. The eggs hatch in 6 - 8 weeks, though the alevin remain within the substrate for up to 2 weeks before emerging into the water column. Young Lahontan cutthroats often move into a lake for a year while young stream dwelling cutthroats stay in the stream margins to feed. Coastal Cutthroat trout
Links to Other Research
	Here's a list of California watersheds where Cutthroat trout may be found. © 2003 - Regents of the University of California Division of Agriculture and Natural Resources Communication Services E-Mail Web Master ANR Non-Discrimination Statement