Conservation relevance of bat caves for biodiversity and ecosystem services

All ecosystems are dotted by salient small natural features that not only characterize them but also significantly add to their biodiversity and functions. These small natural features are prominent but easily missed when ecosystems are described. Caves are one key example of this. Cave ecosystems are underrepresented in conservation planning and implementation around the world and have become mostly overlooked in conservation strategies overall. Caves contain high levels of biodiversity from fungi to invertebrates to vertebrates. This paper emphasizes bat caves as providers of ecosystem services to vast areas surrounding them, in the order of hundreds of thousands of square km just in North America. Their influence extends three-dimensionally via subterraneous water bodies and via the aerial nightly dispersal of the bats that provide a host of services from seed dispersal to pollination to pest control. The examples used focus primarily on free-tailed bats in North America, but the same principles apply to any other cave in the world with significant bat colonies. Caves enjoy protection, legal or actual, in some countries and not in others, and as a result many have suffered damage or been destroyed altogether. Common threats are vandalism, urbanization, and pollution. Many caves are attractive as ecotourism destinations and provide unique opportunities to educate the public about unexpected biodiversity values and ecosystem services. Inventorying caves poses challenges, but efforts are under way to assess caves in need of protection. Incipient cave protection strategies include legal and educational efforts, and management. Although illustrated with bat caves, given the importance of all caves and their precarious status, it is time to call the attention of decision makers about the urgent need to launch a worldwide cave conservation initiative.