Modeling the Effect of Landscape on Mosquito Populations and West Nile virus in Grouse Habitat

Broad Objectives

Objective 1: Assess mosquito species diversity found during sampling efforts in grouse habitat in several regions of Pennsylvania in comparison to DEP sampling results in peridomestic habitat

Objective 2: Compare data on temporal emergence of WNV between DEP sampling locations in peridomestic sites with data collected in nearby grouse habitat to assess if DEP public health surveillance data is relevant to grouse population dynamics

Objective 3: Document WNV prevalence in grouse habitat across landscape gradients, by region and mosquito species, to inform a predictive model of WNV landscape epidemiology in woodland sites

Objective 4: Model mosquito prevalence to create predictive maps of woodland landscape vulnerability to WNV across Pennsylvania incorporating WNV prevalence in vectors and and landscape variables

Since its arrival in North America in 1999, West Nile virus (WNV) has had unprecedented adverse effects on the health of native birds across numerous taxa. In Pennsylvania, WNV was first documented statewide in 2002, with concurrent and precipitous population declines in ruffed grouse (Bonasa umbellus). Recovery of grouse populations has not since been observed. Infected grouse may experience mortality rates as high as 70% or greater (Nemeth et al. 2017). The ongoing influence of WNV can be seen in statewide population indices such as hunter flush rates and late-summer brood sighting survey data. Recent analysis indicates that WNV and availability of young forest on the landscape synergistically influence colonization, persistence and extinction of local grouse populations. Susceptibility of ruffed grouse to ongoing cycles of high-WNV prevalence has important implications for managing this species. This project is in collaboration with the Pennsylvania Game Commission.