The Lahontan cutthroat trout was once a dominant fish at Lake Tahoe
The Lahontan cutthroat trout (LCT) was once the top fish predator in Lake Tahoe. In the mid-1800s when settlers first began arriving at Lake Tahoe, the water was teaming with native cutthroat. These fish, named for the distinctive slash of red under their chins, often weighed in at more than 40 pounds and were easy to catch from shore. Many historic photos show anglers of all stripes, from kitchen workers in aprons to well-to-do gentlemen in neckties, holding up the huge, fleshy fish.
The Truckee River in combination with Taylor, Ward and Blackwood creeks historically provided spawning habitat for Lahontan cutthroat trout occurring in Lake Tahoe. However, the last spawning LCT was observed in these tributaries in 1938.
Here’s what happened: After European discovery in the mid 1800s, Lake Tahoe and the Truckee River system became known for its abundant timber and mineral resources. By 1859 numerous lumber mills were established and began having negative impacts on Tahoe’s fragile environment. The mills discharged sawdust and other logging debris directly into the Truckee River and silt and erosion runoff from timber clear-cutting significantly degraded water quality. Eventually, these practices choked riverbanks and riverbeds with the debris and ultimately prevented fish passage.
During this period, commercial fishermen also took advantage of thousands of large LCT that made their way each spring from Lake Tahoe into the tributaries to spawn. They set up permanent fish traps on the major tributaries and used gill nets and seines to capture these large fish.
By 1880, over fishing, the damage to the LCT’s habitat, and the introduction of non-native lake trout began to take their toll. Commercial fishing was banned in 1917, but LCT in Lake Tahoe did not survive.
LCT outside of the Lake Tahoe Basin also declined. In 1844, there were 11 lake-dwelling populations of Lahontan cutthroat trout and 400 to 600 stream-dwelling populations in over 3,600 miles of streams within the major basins of historic Lake Lahontan. Today, they only occur in 10.7 percent of their historic stream habitat and 0.4 percent of their lake habitat.
LCT was listed as endangered in 1970 and reclassified as threatened in 1975. In 1997, during the Lake Tahoe Presidential Forum, former President Bill Clinton and Interior Secretary Bruce Babbitt called for the Lahontan cutthroat trout to be restored to the Lake.
The U.S. Fish and Wildlife Service is working in collaboration with state, federal, tribal and local partners to restore the lake form of Lahontan cutthroat trout to the Tahoe Basin.
The Lahontan National Fish Hatchery Complex in Gardnerville, Nev., has been stocking Fallen Leaf Lake since 2002 with the strain of Lahontan cutthroat trout native to the Tahoe Basin. They have partnered with researchers throughout the past 10 years to improve their understanding of the existing lake ecosystem and used this applied research to continually improve on their conservation strategies. The applied research has demonstrated opportunities for re-establishing this iconic lake species to Fallen Leaf Lake and Lake Tahoe. The research has improved management strategies for stocking methods, locations and frequency that improves the initial survival of Lahontan cutthroat trout. In recent years, research has documented multiple year survival, improved angler catch rates of Lahontan cutthroat trout, and this year, anglers are catching LCT in Glen Alpine Creek.
Lahontan National Fish Hatchery has taken the experience from Fallen Leaf Lake and applied lessons learned to Lake Tahoe.
A contract research vessel is on the lake throughout much of the year with researchers using hydroacoustic monitoring methods as well as more traditional sampling methods to better understand the existing aquatic ecosystem. Complete hydroacoustic surveys are identifying ecological sub-regions, refining live fish trawling techniques and lakewide surveys of zooplankton.
The lake form of LCT are generally a longer-lived top predator (15-20 years), feeding on any fish species that their mouth gape can accommodate. This year at Pyramid Lake, an angler caught this strain of LCT weighing in at 19.5 pounds at 6 years of age.