Conservation Biology of Bats: Invasive Threats, Research Effort, and Extinction Risk

Global conservation for bats is needed: 15 percent of species are listed as extinct or threatened, signifying that they are at a high risk of extinction. An additional 17 percent are designated data-deficient, denoting that a threat category has not been assigned owing to insufficient knowledge on species abundance or distribution. In this dissertation, I use methods from both ecology and evolution to contribute to the study of bat conservation. Firstly, I review the impacts of biological invasion on bats, and provide examples of threats from each of four broad categories: predation, pathogens, competition, and indirect interactions. Overall, detailed accounts of invasive species threatening bats are lacking, but the most persuasive cases occur on islands. Secondly, I provide a case study of the endangered Pacific sheath-tailed bat (Emballonura semicaudata rotensis) to illustrate the importance of investigating indirect effects of invasion on species of conservation concern. The results imply that the impact of an invasive shrub on the persistence of the bat has been underestimated and that it is unclear how a feral ungulate alters bat habitat aside from reducing understory vegetation. Thirdly, I describe the state of academic literature for most of the bat clade, and provide ranked prioritization of bats for research based upon species vulnerability and evolutionary irreplaceability. Lastly, I use evolutionary comparative methods to identify species of conservation concern. Given simulations using important correlates of bat extinction risk, I predict that 31 data-deficient bats are threatened by endangerment. Overall, my work will benefit bat conservation by highlighting gaps in knowledge and elucidating research priorities that will be useful for directing conservation action.