A review of rotenone use for the control of non-indigenous fish in Australian fresh waters, and an attempted eradication of the noxious fish, Phalloceros caudimaculatus

Rotenone has been used as a piscicide in Australia for c. 45 years. In freshwater systems this use has focused on the control of non-indigenous fish species. Little of this use has been registered, reported or documented and Australian fisheries researchers and managers are forced to rely on international literature. This paper reviews all available documentation relating to rotenone use in Australia, before discussing some planning and application issues that may be faced by those considering rotenone use. A recent attempt to eradicate a population of noxious poeciliid fish (Phalloceros caudimaculatus) is used as a case study. Although this effort was conducted in a closed system, dense aquatic vegetation prohibited adequate mixing of rotenone and allowed the survival of target fish in areas with low rotenone concentrations. Several months later, the target species persisted at the treated site. If similar systems are to be treated in the future, we suggest that pools are drained before application. We also recommend that the current legislative arrangements for rotenone use in Australia are reviewed, to encourage the proper documentation of eradication events.