This project will study ecological and social processes governing the structure and function of wetland ecosystems found in agricultural and rangelands in the Sierra Foothills of California where they have often been accidentally or purposefully created. These wetlands are important habitat for a threatened bird species, Black Rail, and can be a source of mosquitoes that carry the recently-arrived West Nile Virus, which affects both humans and wildlife. The goal of this research is to address the question of how landowner practices, attitudes, and perceptions of the costs, risks and benefits of maintaining wetlands have affected their number, size, and distribution, and in turn influenced mosquito populations, West Nile Virus prevalence, and the population dynamics of the Black Rail. The project will trace the appearance and disappearance of wetlands over the last 50 years from aerial photographs to develop measures of wetland change; survey wetland landowners to determine how they assess the costs and benefits of their wetlands; develop regional climate models that project the change in wetland size over the next 40 years with changing climate and irrigation practices; develop population models for rails that incorporate changes in wetland characteristics; quantify the relationships between the risk of being exposed to West Nile Virus and climate, land use, and wetland characteristics; and develop models that integrate these factors to forecast future changes in wetlands.
Over 90% of California's wetlands have been converted to other land uses. This project will quantify the processes that sustain the remaining inland wetlands on agricultural landscapes by uncovering interactions between wetlands, landowner decisions, and climate variation. Educational benefits include training of postdoctoral researchers, and graduate and undergraduate students in research methods including opportunities for minority student participation, and developing course material for undergraduate and graduate students. Results from this research will be disseminated to a broader community through outreach to landowners, agencies, and stakeholders that manage wetlands in working landscapes. This work will also inform conservation efforts for a threatened species, the Black Rail, by determining impacts of disease and by providing models to evaluate regional development and landscape planning in a rapidly growing region of California.