The epidemiology of avian pox and interaction with avian malaria in Hawaiian forest birds

Despite the purported role of avian pox (Avipoxvirus spp.) in the decline of endemic Hawaiian birds, few studies have been conducted on the dynamics of this disease, its impact on free-living avian populations, or its interactions with avian malaria (Plasmodium relictum). We conducted four longitudinal studies of 3-7 years in length and used generalized linear models to evaluate cross–sectional prevalence of active pox infection and individuals with healed deformities that had recovered from pox. Our goal was to understand how species, season, elevation, malaria infection, and other biological characteristics influenced pox infection in ‘Apapane, Hawai`i ‘Amakihi, ‘I‘iwi, and Japanese White-eye across low-, mid-, and high-elevation forests on the island of Hawai`i. We also used multi-state capture-recapture (longitudinal) models to estimate pox infection rates, recovery rates, and potential pox-related mortality. Pox infection rates were typically highest in low-elevation forests, f...