Modeling the Risk of West Nile Virus to Ruffed Grouse Populations in Pennsylvania

West Nile virus (WNV), a virus transmitted by mosquitoes, causes high mortality in many native birds. As WNV spread through Pennsylvania in 2000-2002, populations of ruffed grouse (Bonasa umbellus) - the Pennsylvania State bird- suffered significant declines. Statewide grouse populations remain at record lows. WNV has been well-studied in human-dominated environments, but epidemiology in woodland systems is little-understood despite population-level declines in vulnerable species. This project will further the knowledge of woodland epidemiology of WNV and its associated vector in the habitat of a highly-susceptible species (grouse). The project will analyze 15 years of public health surveillance data, in conjunction with targeted mosquito trapping across 19 forested study areas, to identify climatic and landscape characteristics driving vector abundance and WNV prevalence in woodland systems. Our interdisciplinary team will trap woodland mosquito vectors in multiple study areas within every region of Pennsylvania, across a spectrum of factors thought to influence occurrence (elevation and distance from anthropogenic land uses). 

We will characterize mosquito breeding pools to and test the feasibility of site-level population control. This information will guide conservation efforts by modeling risk for susceptible woodland species at a level that has not previously been attempted. This will generate important data for human health surveillance since WNV relationships occurring between urban/suburban/village and woodlands remain unknown. WNV is a ‘classic’ climate change disease; prevalence and severity responds to altered precipitation and increased warming. Woodland wildlife and rural residents of Pennsylvania will likely face increased WNV threat over time. Thus, the role of climate in vector abundance and virus prevalence must be better understood. This collaboration will protect human and wildlife health by defining high-risk areas and formulating approaches to reduce WNV risk in woodland areas. 

Resulting Publications

• Bondo, K.J., D. Montecino-Latorre, L. Williams, M. Helwig, K. Duren, M. Hutchinson, W.D. Walter. Predicted distribution of two mosquito vectors (Culex restuans and Culex pipiens) of West Nile virus using integrated nested Laplace approximations.
• Bondo, K.J., D. Montecino-Latorre, L. Williams, K. Duren, W.D. Walter. A case study using vector surveillance and large-scale spatial data to determine vulnerability of ruffed grouse to West Nile Virus.