Efficacy of Commercially Available Quaternary Ammonium Compounds for Controlling New Zealand Mudsnails Potamopyrgus antipodarum

Abstract

The New Zealand mudsnail Potamopyrgus antipodarum is an invasive species that can be transported to and established in new bodies of water on gear used by aquatic professionals, anglers, and aquatic recreationists. Sparquat 256, a standard disinfectant for controlling the spread of mudsnails, was recently discontinued by the manufacturer. Our objective was to find an industrial-strength, commercially available quaternary ammonium compound (QAC) that could replace Sparquat 256 for disinfection purposes. The efficacy of three products—Quat 4, Green Solutions High Dilutions Disinfectant 256 (GS 256), and Super HDQ Neutral (Super HDQ)—were tested using bath disinfection at multiple concentrations and exposure durations. For bath disinfection purposes, GS 256 and Super HDQ were the most effective. Super HDQ caused higher mortality rates at 48 h postexposure and was therefore tested and found to be highly effective for spray disinfection to prevent transporting mudsnails on field equipment. Regardless of the QAC chosen, we recommend a bath disinfection rate of 0.4% and a spray disinfection rate of 0.8% QACs in solution with an exposure duration of 10 min. These concentrations meet or exceed minimum effective disinfection requirements for quagga mussels Dreissena rostriformis bugensis, zebra mussels Dreissena polymorpha, whirling disease Myxobolus cerebralis, and chytrid fungus Batrachochytrium dendrobatidis.

Received January 8, 2015; accepted November 8, 2015 Published online March 22, 2016

Acknowledgments

This work was sponsored in part by the Colorado Parks and Wildlife Aquatic Nuisance Species Program. The authors would like to thank G. Schisler for his assistance with New Zealand mudsnail collection and consultation on experimental design, E. Brown for her assistance in obtaining chemicals and equipment, and W. Keeley and City of Boulder Open Space and Mountain Parks for allowing us to collect mudsnails in and conduct the spray disinfection experiment at Dry Creek.