When we hear about “poisons” in our streams, we all get concerned. It is one of the main reasons many of us get involved with Trout Unlimited in the first place. In New Mexico, TU has fought against mining discharge from the Molycorp mine in Red River, we are a major player in keeping energy development and the resulting chemical runoff out of the Valle Vidal, were instrumental in developing the Governor’s recent roadless petition, have testified in favor of ONRW status to protect both the Rio Santa Barbara and the Valle Vidal and have participated in efforts to make sure that the discharge permit for Taos Ski Valley is not altered to allow for more effluent.

That said, Trout Unlimited is fully in favor of the effort to remove the non-native fish from streams when necessary to restore the native fishery. Exotic fish such as brown, brook and rainbow trout are incompatible with our native fisheries, and are one of, if not the primary reason native trout throughout the west are in so much trouble. TU has studied the impacts of both rotenone and antimycin, both on the watersheds and on animal and human health, and have found that there really is no impact. Without these chemicals, there is a strong possibility that the Gila trout would be extinct now, and that the Rio Grande cutthroat trout would be listed as endangered.

The chemicals in question are organic in nature, do not bio-accumulate, are in the stream for a short period of time, and in quantities that are far below EPA standards. These chemicals are also neutralized at the end of the treatment section.  These chemicals are so toxic to fish that they are applied to the streams in very small quantities, on the order of 10-40 parts per billion. That would be equivalent to a teaspoon of sugar in an Olympic sized swimming pool. Alternatively, at these quantities, they have no impact on humans, even in the treatment areas.

It is our opinion that the best thing we can do for the biological integrity of our streams
is to remove these non-native intruders and return the native fish community. The following document the TU policy on piscicide use and some imformative papers that have been put together regarding the risks of these chemicals:

TU National Piscicide Policy Summary (Word document)

TU National Piscicide Policy (Word document)

Rotenone. A Brief Review of its Chemistry, Environmental Fate, and the Toxicity of
Rotenone Formulations (pdf)
Kevin C. Ott, Ph.D

Antimycin. A Brief Review of It’s Chemistry, Environmental Fate, and Toxicology (pdf)
Kevin C. Ott, Ph.D

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