Grand Teton National Park will initiate a project to protect native aquatic communities by using a chemical pesticide treatment to kill non-native species in the Kelly Warm Spring and outflow the week of August 20. A temporary closure will be implemented in the areas affected by the treatment, and the treated areas will be signed.
Kelly Warm Spring is located in the southern area of the park, about one mile northeast of the community of Kelly, Wyoming. The spring has been the target for illegal dumping of aquarium fish for decades. The non-native fish species are swordtails, convict cichlids, guppies, goldfish, and tadpole madtoms.
These tropical and warm water aquatic species are harmful to native fish, and capable of surviving a range of water temperatures. The non-natives persist in the warm spring and its outflow areas of Savage Ditch and Ditch Creek. These areas are located within a mile of the Snake River. These exotic species have not been found in the Snake River to date, but they could be present.
The aquarium fish are a detriment to native fish, including Snake River cutthroat trout, bluehead suckers, Utah suckers, Utah chubs, redside shiners, longnose and speckled dace. The nonnative fish prey on native fish eggs and juveniles, deplete the food sources used by native fish, and spread disease.
After considering public comments and environmental effects, the park has approved a categorical exclusion under the National Environmental Policy Act for control action based on restoration of noncontroversial native species into suitable habitats within their historic range and elimination of exotic species.
Park biologists considered several alternatives to remove the exotic species, such as netting and trapping, electrofishing and pesticide treatment. Based on scientific review, public input and consultation with Wyoming Game and Fish Department, park biologists identified pesticide treatment as the preferred method.
Due to the large number of very small fish that can hide in algae mats in the spring, resource managers have determined that the short-term use of an approved chemical pesticide, rotenone, is the most effective method to control aquatic invasives in Kelly Warm Spring.
Rotenone readily oxidizes, breaks down rapidly in sunlight, is not readily absorbed by non-target organisms, and has a low toxicity at concentrations proposed for treatment. This treatment has been safely used in streams throughout the Greater Yellowstone Ecosystem and other national parks across the country.
Proposed treatments are planned when stream discharges are low, thereby limiting the size of the treatment area and downstream effects. Fisheries will be monitored and restocked with native fish as needed.
National Park Service policy and regulations emphasize protection of native species and processes and prohibit the introduction of non-native wildlife, fish or plants into a park ecosystem. Signs and additional educational measures will be implemented to eliminate the chance of reinfestation of “aquarium” fish into Kelly Warm Spring.