Redfish Lake in Stanley, which sits at the base of the Sawtooth Mountains, has increasingly become a hot spot for visitors to camp, fish, boat, and do other recreational activities.
The lake sits at the headwaters of the Salmon River where its water flows north to meet the Snake River and continues to the Columbia River and the Pacific Ocean.
Up until the late 1950s, according to the US Department of Agriculture, more than 4,000 Sockeye Salmon traveled 900 miles from the ocean to spawn in the lake. The bright red color of the Sockeye Salmon gave the Red Fish Lake its name.
Sockeye salmon are red because of their diet. They gain 99% or more of their body mass in the ocean and the food that they eat there is high in carotenoids. The pigments from this substance are stored in their flesh, causing their red appearance.
“As salmon approach their spawning grounds they begin to absorb their scales,” the National Park Service website notes. “The carotenoid pigments in their flesh are transferred to the skin and eggs. By the time they spawn, their flesh is truly white because of all the carotenoids have been moved out of the flesh.”
The red skin also makes them more visible and may signal their readiness to spawn. The pigments may also help the fish absorb oxygen from the water.
The future of the red fish
While thousands of these red fish used to spawn in the lake, only a few dozen return from the ocean each year due to dams blocking their route. In 1991, the sockeye was listed under the federal Endangered Species Act.
In 2021, Idaho Fish and Game reported that only 44 sockeye naturally returned to the Sawtooth Basin. However, in the fall, Idaho Fish and Game biologists released over 1,100 hatchery adults into Redfish Lake.
To learn more about Idaho and Fish and Game’s sockeye program and what is being done to reintroduce sockeye salmon back into Red Fish Lake, click here.