ABSTRACT
ABSTRACT National Park Service (NPS) management actions at Lake Powell prevented dreissenid infestation for many years despite the lake being at very high risk. Early recognition of the danger, administrative controls, education and outreach, and screening of watercraft to assess risk are credited with keeping mussels out. After invasive mussels were established in the western United States, infestationof Lake Powell was averted through further, even more aggressive actions. An extensive monitoring program was developed for early detection of dreissenid mussels. Indicators of invasive mussels in Lake Powell were detected by the NPS in 2012, 14 years after scientists had predicted Lake Powell would become the ‘rst western infested waters.
