Cost-effectiveness of aquatic invasive species prevention techniques

Abstract

Aquatic invasive species (AIS) are a growing threat to water resources resulting in re-engineered ecosystems and expensive management actions. Boater education, watercraft inspection, and hot water decontamination are popular prevention strategies for AIS that spread through the recreational boating pathway; however, few studies have quantified the effectiveness of these approaches. In this study we estimated the effectiveness and costs of AIS prevention practices performed by boaters, watercraft inspectors, and hot water decontaminators. To estimate effectiveness, participants (n=144) recruited at public water access sites in Minnesota and Wisconsin and were asked to inspect and remove AIS from a boat that had been realistically staged with macrophytes, zebra mussels, and spiny water flea. The types of organisms and the amounts of AIS removed were used to estimate effectiveness for each prevention method. Additionally, interviews with MN county AIS managers were conducted to gather itemized spending information on the three preventions in question. Our results suggest that watercraft inspection is a cost-effective method of prevention for most boats and hot water decontamination is an important tool for high-risk boats, however decontamination protocols are difficult to effectively execute. Furthermore, boater education helps reduce risk when inspectors cannot be present at public water access sites due to limited funding and staffing. Ultimately, these data will be incorporated into the online decision support tool, AIS Explorer (www.aisexplorer.umn.edu) to guide future management decisions.