Integrating Acoustic Mapping into Operational Aquatic Plant Management: a case study in Wisconsin

Efficient planning, execution, and post-treatment monitoring of a submersed aquatic plant management operation require early detection and detailed information on the distribution of target and nontarget species within the treated waterbody. This requirement was the motivation behind the development of the acoustic-based Submersed Aquatic Vegetation Early Warning System (SAVEWS (TM)). After initial development in the late 1990s, the associated processing software was licensed to Biosonics, Inc., and is currently marketed as EcoSAV (TM), along with the required hardware for conducting acoustic plant surveys. Since becoming commercially available ill 2001, approximately 70 systems are in rise world wide. While the system is used by a number of aquatic plant management researchers and operators, by far greater use is found in other fields, primarily ecological and applied studies of estuarine vegetation and coastal hydrography. While usage in any form is considered beneficial, a significant potential for operational usage within the aquatic plant management field is largely unrealized. Discussions with various aquatic plant management personnel identified concerns related to using the system operationally, including system acquisition and operations cost, data processing complexity, data accuracy, and acceptance by regulatory agencies. To address these concerns, a mapping demonstration was pelf formed in Conjunction with a chemical control application to treat Eurasian watermilfoil (Myriophyllum spicatum) in a 515-acre (2.08 km(2)) Wisconsin lake. One pretreatment and 2 post-treatment Surveys were conducted. A ground-truth sampling effort was performed as part of the first. post-treatment survey. The cost of conducting the mapping survey is broken out in terms of equipment costs and labor for planning, execution, and data analysis. We present techniques and summaries for data analysis and evaluate the added value of information provided by acoustic mapping to the overall management operation.