Invasive Aquatic Vegetation Management in the Sacramento–San Joaquin River Delta: Status and Recommendations

https://doi.org/10.15447/sfews.2017v15iss4art5 Widespread growth of invasive aquatic vegetation is a major stressor to the Sacramento-San Joaquin River Delta, a region of significant recreational, economic, and ecological importance. Total invaded area in the Delta is increasing, with the risk of new invasions a continual threat. However, invasive aquatic vegetation in the Delta remains an elusive ecosystem management challenge despite decades of directed scientific research and prioritized policy recognition. In this paper, we summarize the current state of knowledge of the history, status, and potential future directions for coordinated research, management actions, and policy based on topics discussed at symposium head on invasive aquatic vegetation on September 15, 2015. Remote sensing technology, mechanical, chemical, and biological control, as well as community science networks have all been shown to be effective management tools, but overall effectiveness has been hindered by complex regulatory structure, the lack of a consistent monitoring program, regulations that restrict treatments in space and time, and funding cuts. In addition, new management options depend on continued research and development of new active ingredients for chemical control and testing of biological control agents. The ongoing development and implementation of new strategies for adaptive, integrated management of aquatic weeds, using currently-available management tools, new knowledge derived from remote sensing and plant growth models, and an area-wide, ecosystem-based approach, is showing promise to achieve improved management outcomes and enhance protection of the Delta’s water resources