Holocene population baselines of an endangered bat in the southeastern US: multi-millennial resilience to climate change and humans

Abstract We radiocarbon dated guano deposited by the endangered gray bat ( Myotis grisescens ) in Cave Springs Cave, USA, to reconstruct bat population changes over the last ∼10,000 years. We resolve a ∼10,000 year period of bat resilience to climate and humans (locally and regionally) in the Holocene. But our data also suggest that bat populations were affected by the onset of more arid hydroclimate conditions and the development of new regional human land use ∼4,500 years ago. Overall, our analyses highlight the importance of mitigating hydroclimate and regional anthropogenic impacts for gray bat conservation efforts. Further, our approach represents an important new methodology for understanding bat population changes without impacting the bats themselves and on timescales exceeding observational records, opening many new doors for future research.