Poisoning Smallmouth Bass in Fossil Creek

We have been following the story of the Arizona Fish and Game Commission’ poisoning of smallmouth bass in Fossil Creek. This had some smallmouth bass fans pretty upset. After all, in some parts of the country we are struggling to maintain healthy bass populations.

Poisoning smallmouth bass in Fossil Creek

Crews last week used chemicals to kill smallmouth bass in a 2.5-mile-long stretch of Fossil Creek, invaders that had already spawned and so threatened to wipe out one of the premier refuges for endangered native fish in the Southwest.

The six-man crew spent weeks netting perhaps 100-300 native fish to move upstream, before using a chemical to kill all the fish remaining in the final 2.5 miles of the stream before it merges with the Verde River.

They set up a dispenser to inject Rotenone into the water, a chemical that essentially smothers any gill-breathing creature. Laboratory tests have shown that the chemical can cause Parkinson’s-like symptoms in laboratory animals. However, the concentrations used to kill the fish in a stream remain far below those levels. The chemical breaks down quickly into harmless byproducts. In addition, the crews released a second chemical that neutralized any lingering traces once it had killed all the fish in that 2.5-mile stretch of stream. Source

This scenario is difficult to judge because it is always best to preserve native species. Sometimes it is a losing battle and you can’t fight invasive species because they sometimes overwhelm a habitat or they can establish an equilibrium leading to minimal disruption of native species.

It is sad to see the poisoning of our favorite species in Fossil Creek but I suspect that if there was a predator that threatened to wipe out the smallmouth bass, we would feel the same way.