By Montana Grant

Posted: September 5, 2019

The Gibbon River in Yellowstone Park is full of non-native trout. Brooks, rainbows, and browns currently reside here. The upper section, from Gibbon Falls to above Norris Junction is being poisoned to remove these non-natives.

The upper watershed is off limits from Sept.2 to Sept. 13. A poison called Rotenone is being applied, to kill the fish. This chemical affects the gills of the fish. The chemical neutralizes quickly, and an additional chemical agent will be added, downstream, to remove any affects of the poison. A second application may be needed. Scavengers, humans, and predators can eat the dead fish without any issues. Other critters are also safe from the chemicals.

The headwaters of the Gibbon begin at Wolf, Grebe, and Ice Lakes. The only original species of fish in the river are a type of sculpin. Many of the waters in Yellowstone Park were barren of trout prior to becoming a National Park. The Gibbon was the first fishery in the park where managers stocked Brook Trout in 1905. Later, an assortment of rainbows, browns, and brooks found their way into the watershed. I remember helping stock trout along the banks of the Gibbon in the fly fishing only section. The buckets that I carried were full of Big Brown trout. Many of the Park’s trout were raised in remote Park lakes, like Grebe Lake, to be stocked into the Park waters.

As a child, I learned to fly fish along the Gibbon, near the Norris Campground. Some of the first trout I caught were here. Moose, elk, and buffalo often watched a young Montana Grant mastering his fly fishing craft. My mother would sit on a blanket nearby, drinking coffee, and reading a book. These are fond memories.

Mr. Dennis, a friendly camper and mentor, showed me the fishing ropes. He always wore a pair of overalls and used an old bamboo rod with a Pflueger reel. I netted an 8 lb. brown for him just above the bridge at Norris Junction. It was the biggest trout that I hade ever seen. He released it for another day.

To get the river back to a more “native” normal, the Gibbon will be restocked with Arctic Grayling and Westslope Cutthroat trout. These natives will be stocked in 2020 or 2021.

The Gibbon should become an amazing fishery for these rare native trout.

Montana Grant

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