Spiny waterflea webinar on Dec. 19!
Massive Ecological and Economic Impacts by Invasive Spiny Waterflea Outbreak in Lake Mendota, WI
Aquatic invasive species can alter complex food web interactions that are important to how lakes provide ecosystem services – the benefits humans derive from nature. Outbreak of the invasive predatory zooplankton, spiny water flea (Bythotrephes longimanus) in Lake Mendota in Madison, WI led to a 60% decline in the keystone algae-eating herbivore Daphnia pulicaria, and in turn, a 3 foot decline in water clarity – a service we estimated to be worth over $100 million to Dane County. We found that these damages to water clarity could be offset by a 71% reduction of agricultural phosphorus runoff into the lake, costing anywhere from $80 million to $160 million. Such extreme cases of economic damages call for increased investment in the prevention and control of aquatic invasive species to better maximize the economic benefits of management decisions in lakes. This call is particularly relevant for the tens of thousands of lakes in the Upper Midwest that provide enormous value in ecosystem services and are vulnerable to over one hundred nonnative aquatic species. Our results highlight the need to more fully incorporate ecosystem services into our analysis of aquatic invasive species impacts, management, and public policy.