Included on the Ultimate USA Cutthroat Map, plus PDFs and KMZs providing additional information are available from the download system.
Note: Lahontan Cutts are officially listed as a “Threatened Species”. Nevada fishing regulations, however, generally treat the Lahontan like any other cold water game fish. A few streams are closed to fishing (check Nevada regulations). Please practice catch and release even where not required by state regulations.
Lahontan Cutts are a miracle. They were originally native to a Lake Lahontan which, at the end of the last ice age (14,000 years ago), covered much of north-western Nevada and touched on eastern California. As the earth heated up, and the area grew increasingly dry, the “pluvial” lake shrank to individual rivers, streams, and lakes within the original basin, stranding individual pockets of Lahontan Cutts. Even more remarkably, the trout adapted to their new conditions, becoming tolerant of higher temperatures and able to survive in streams which would partly dry-up during the peak of summer.
Historically, Lahontans inhabited both lakes and streams across their range. The lacustrine trout could grow to enormous sizes (photos show early 20th century ‘sports” showing-off 20 lbs. Lahontan cutts). Unfortunately, most of the lakes were at some point stocked with Lake Trout, which dominated the cutts, and generally extirpated them. Today, with rare exceptions, Lahontans survive only in the headwaters of streams, where intermittent flows or other barriers isolate them from exotic trout competitors (typically stocker-strain rainbows with which they will readily hybridize).
Streams shown on the Ultimate Cutthroat Map were located in the appendixes of the Lahontan Cutthroat Trout 5-Year Review: Summary and Evaluation by the USFWS, 2009. This contained no stream-level population data; however, a 2004 report entitled Species Management Plan for the Upper Humboldt River Drainage Basin by the Nevada Department of Wildlife does provide some information for a subset of the streams. This information, while quite old, should provide some relative guidance and is linked to the appropriate stream where available.
Source: USFWS, 2009, NVDW