Selective Removal of Nonnative Fishes Using Supaverm®: Toxicity Screening for a Candidate Species-Specific Piscicide

ABSTRACT

I evaluated the chemical Supaverm® for potential use as a selective piscicide by testing its toxicity to native and nonnative fishes commonly found in Arizona. In repeated laboratory tests, Supaverm® dosed at 13 μg/L killed nonnative fathead minnow (Pimephales promelas), red shiner (Cyprinella lutrensis), yellow bullhead (Ameiurus natalis), largemouth bass (Micropterus salmoides) and smallmouth bass (Micropterus dolomieu) without harming native longfin dace (Agosia chrysogaster), Gila chub (Gila intermedia), or Gila topminnow (Poeciliopsis occidentalis). The apparent selectivity of this chemical makes it a good candidate for further evaluation as a species-specific fish toxin.