Restoration efforts have occurred in the Silver King Creek basin for more than 60 years and the PCT populations are monitored annually. To increase their protection, progeny of the 1912 shepherds’ transplant were planted in other fishless waters of the Sierra Nevada, outside the species’ historic range, creating out-of-basin refuge populations.
The Paiute Cutthroat Trout Restoration Project was developed to eliminate threats from non-native fish, restore the PCT to its historical habitat, and ensure the minimum habitat requirements for long-term survival. The PCT is a federally-listed threatened species, and this restoration work is a major component of the recovery effort. The plan to remove non-native fish below Llewellyn Falls was implemented from 2013 through 2015. During this phase of restoration project, the stream was treated with rotenone (a piscicide) to remove non-native trout from Silver King Creek and associated tributaries between Snodgrass Creek and Llewellyn Falls.
Chemical treatment was the preferred alternative identified in the Paiute Cutthroat Trout Restoration Project Final EIR/EIS. Rotenone is a naturally occurring chemical compound derived from the roots of tropical plants in the bean family. Rotenone compounds have been used for centuries, all over the world, to stun and kill fish. Rotenone is used successfully throughout the U.S. as a management tool to eliminate invasive fishes and restore native populations. The U.S. Environmental Protection Agency has concluded that rotenone use for fish control does not present a threat or risk of unreasonable adverse effects to humans or the environment. For more information on rotenone visit the American Fisheries Society Rotenone Stewardship Program.
Following the chemical treatment project, the CDFW and its partners conducted a three-year evaluation (2016 through 2018) to ensure the treatment was successful. CDFW and our partners—the U.S. Fish and Wildlife Service (USFWS) and USFS begin returning PCT to Silver King Creek today—Sept. 18, 2019. PCT are already colonizing restored habitat from upstream sources, but restocking will help reestablish the population more quickly.
This restoration project will expand the population’s protected stream habitat by approximately 11 miles and serve as a buffer against extinction from threats such as wildfire, drought, and disease. Since the amount of habitat for the fish will almost double, a much larger population of PCT is expected to exist in the future. A larger population will be more resistant to the genetic threats that small, isolated populations face over time. When the species is restored to its historic range, we anticipate that a stream segment could be opened to a special regulation fishery for anglers to catch and release PCT.
The recovery of PCT is a multi-agency collaborative effort guided by the U.S. Fish and Wildlife Service Revised Recovery Plan for the Paiute Cutthroat Trout (PDF). The CDFW is committed to continuing our partnership with the USFWS and USFS in the restoration and annual monitoring of PCT to ensure this species persists into the future.