Hoff, S., Hoyt, J.R., Langwig, K.E., Johnson, L., Olson, E., O’Dell, D., Pendergast, C.J., Herzog, C.J., Parise, K.L., Foster, J.T. and Turner, W.C. (2025). The importance of peripheral populations in the face of novel environmental change. Proceedings of the Royal Society B Biological Sciences, 292(2038). doi:https://doi.org/10.1098/rspb.2024.2331.
Abstract
Anthropogenically driven environmental change has imposed substantial threats on biodiversity, including the emergence of infectious diseases that have resulted in the decline of wildlife across the globe. In response to pathogen invasion, maintaining diversity within host populations across heterogenous environments is essential to facilitating species persistence. Peripheral populations occurring in environmental refugia may persist if the environmental heterogeneity they experience leads to altered host-pathogen dynamics and reduced effects of the disease on individuals. White-nose syndrome is an emerging fungal pathogen that has caused mass mortalities of hibernating bat species across North America. However, in the northeastern U.S., coastal populations of the federally Endangered northern myotis (Myotis septentrionalis) appear to be persisting despite infection while mainland populations in the core of the species range have experienced sharp declines. Thus, this study investigated host and environmental factors that may contribute to divergent population responses. We compared patterns of pathogen exposure and infection intensity between island and mainland populations and documented the environmental conditions and host behaviors that may promote survival despite disease invasion. For island populations, we found lower prevalence and less severe infections, possibly due to a reduced hibernation duration of up to ten weeks compared to mainland populations which likely reduces time for disease progression. The coastal region of northern myotis range may serve as habitat refugia that enables this species to persist despite pathogen exposure, however conservation efforts will be critical to supporting species survival in the long-term.