ST. GEORGE — The Utah Division of Wildlife Resources will conduct a native Bonneville cutthroat trout restoration project within the Mammoth Creek drainage area in Dixie National Forest.
The project will begin Sept. 9, and will result in the temporary closure of Dead Lake, Porcupine Lake and the unnamed tributary to Mammoth Creek draining area for the public’s health and safety.
The project was identified as a priority for Bonneville cutthroat trout conservation strategy, which is designed to prevent the fish from being listed under the Endangered Species Act.
A rotenone treatment will be used to rid all species of fish in targeted streams, ponds, lakes and tributaries in order to restore the native Bonneville cutthroat trout to a portion of the Mammoth Creek drainage area.
This treatment will build on restoration work already completed in Castle Creek and Lowder Creek, as well as non-native trout removal conducted earlier this summer in Reed Valley Creek. When the entire project is completed, nearly 30 miles of the Upper Mammoth Creek drainage area will be restored for native Bonneville cutthroat trout.
The active ingredient in liquid rotenone is a powder derived from the roots of a South American plant. Rotenone is specifically poisonous to gilled organisms because it interrupts oxygen uptake from the water at the cellular level.
Although liquid rotenone is relatively benign to humans, fish treated with the chemical have not been cleared by the Food and Drug Administration for human consumption. For that reason, fish that die during the project cannot be salvaged.
Depending on their location, most rotenone drips will run for three to eight hours. Applying the rotenone this way will ensure that all of the freshwater sources are simultaneously treated. Charges for drip stations are calculated to apply the 5% active ingredient liquid rotenone at a concentration of 1.5 parts per million in the target area.
After the rotenone has been applied, potassium permanganate, an oxidizing agent, will be applied to treated waters below the target area to neutralize the rotenone in those areas.
For more information on this project please contact the Utah Division of Wildlife Resources at 435-691-2204 or Mike Golden, a Dixie National Forest Fish Biologist, at 435-865-3700.
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