Multiscale model of regional population decline in little brown bats due to white‐nose syndrome

Andrew M. Kramer
Claire S. Teitelbaum
Ashton Griffin


1. The introduced fungal pathogen Pseudogymnoascus destructans is causing decline of several species of bats in North America, with some even at risk of extinc‐tion or extirpation. The severity of the epidemic of white‐nose syndrome caused by P. destructans has prompted investigation of the transmission and virulence of infection at multiple scales, but linking these scales is necessary to quantify the mechanisms of transmission and assess population‐scale declines.2. We built a model connecting within‐hibernaculum disease dynamics of little brown bats to regional‐scale dispersal, reproduction, and disease spread, includ‐ing multiple plausible mechanisms of transmission.3. We parameterized the model using the approach of plausible parameter sets, by comparing stochastic simulation results to statistical probes from empirical data on within‐hibernaculum prevalence and survival, as well as among‐hibernacula spread across a region.4. Our results are consistent with frequency‐dependent transmission between bats, support an important role of environmental transmission, and show very little ef‐fect of dispersal among colonies on metapopulation survival.5. The results help identify the influential parameters and largest sources of uncertainty. The model also offers a generalizable method to assess hypotheses about hibernacu‐lum‐to‐hibernaculum transmission and to identify gaps in knowledge about key pro‐cesses, and could be expanded to include additional mechanisms or bat species.