Fishing for Answers at Stanley Lake

The Alpine Examiner

June 17, 2023

Naturalist Blog

Getting to the heart of what matters in the Sawtooth National Recreation Area

Fishing for Answers at Stanley Lake

As an active fisher, I always keep an eye out for people fishing and ask them for more information about it. On my most recent trip out to Stanley Lake, I ran into a father and daughter who were fishing on the shoreline. I stopped to tell them my normal roving naturalist spiel and then asked my own question. I asked with genuine curiosity, “Have you guys caught anything? And are you trying to catch any fish in specific?” The father kindly answered, telling me they had just started and weren’t looking for anything in particular. He proceeded to ask me if I had noticed the large fishing boat that was out a few minutes ago. I exclaimed yes, and that I was wondering what they were doing. The father, who had more insight on the matter, told me that they were removing most of the fish from the lake and that he didn’t know what they did with them. Being someone who loves both spinner rod and fly fishing, I was immediately intrigued to know what fish they removed and why. I went fishing for answers.

View of Stanley Lake and McGowan Peak. Photo by Clare Vergobbi

After putting on my waders, fishing around for information, and conducting some research, I stumbled upon the answer! From the past 3 years, Idaho Department of Fish and Game have been removing lake trout from Stanley Lake. It turns out that lake trout are a hyper carnivorous fish. This means that the trout eat other smaller fish and organisms that live in the water. These smaller fish include young sockeye and kokanee salmon. Lake Trout are also known to be able to spread to close by waters and reproduce quickly. These trout are able to dominate bodies of water. This means that they could threaten populations of salmon and other fish.

Lake Trout, Idaho Department of Fish and Game

Now you might be asking why these lake trout are such an issue? All fish reproduce, and some are also carnivorous. The problem is related to what kind of prey the trout eat: salmon. Stanley and Redfish Lakes used to be the habitat for hundreds of thousands of sockeye and kokanee salmon. Due to overfishing and the installment of multiple dams that block the salmon’s migration routes, populations have declined drastically. Sockeye and kokanee salmon are endangered in Idaho. In the past, these salmon supplied people with food and recreation, were a major food source for wildlife, and brought nutrients from the ocean to the nutrient-poor Stanley Basin. The removal of the carnivorous lake trout is part of a salmon restoration effort.


The removal of these predatory fish is only a three-year long project, this was the last year. In the late summer and fall, sterile (unable to reproduce) lake trout will be added back to Stanley Lake. This will help to keep the population size of lake trout controlled so they do not consume the entirety of the salmon population, which are both a game and recreation fish, and also are important to the health of the natural aquatic environment. Unfortunately, I am not sure what happens to the lake trout once they are netted. My hypothesis is that they are euthanized or perhaps go through a sterilization process. If they are in fact killed, I hope in the future that they would be sold to others as a food resource or bait. The efforts made to restore wild and clipped salmon by local fish hatcheries and Fish and Game are commendable and beneficial. I would love to see the natural salmon populations restored in the near future.


If you are in the need of a fishing license, they are available at the Stanley Fly Shop or the Mountain Village Mercantile in Stanley.




Julia was a 2022 Naturalist. She came to Idaho from Rochester, New York with a degree in Biology and enjoyed teaching and learning about the plants and the fish of the Sawtooths.