Bat study rounds first year

08/02/2018

The first year of the Marin Bat Monitoring Project has revealed interesting data about the 13 bat species found in Marin. The project, undertaken by the United States Geological Survey and One Tam, is focused on identifying the feeding and roosting sites of local bat species. Although feeding sites can be identified using acoustic data derived from their calls, the study of roosting sites requires capturing individual bats using mist nets—which don’t harm the creatures, but allow researchers to attach a location monitor that stays on for two weeks. So far, the project has identified each of the 13 local species, and found that up to eight species can cohabit a single feeding site. The largest feeding site in the Point Reyes National Seashore has five species. “People have this image that bats are really scary and evil,” said Point Reyes National Seashore spokesman John Dell’Osso, “but they’re probably one of the most important pollinators worldwide and the best mosquito repellant that I know of.” The information gathered about bats’ habits will help scientists monitor them and surveil for the deadly white nose syndrome, which has been found in Washington State. The results of the project will have wider implications, too, as half of the bat species in California are found in Marin. “One of the nice things about Marin County is that there is just so much protected land,” U.S.G.S. bat expert Gabriel Reyes said. “There is a continuum of protected habitat for them.” Of the 13 species, Dr. Reyes estimates that three may be passing through migration corridors in Samuel P. Taylor State Park and along Redwood Creek, flying north in the spring to raise pups in Canada and south in the fall. The rest stay put in Marin, choosing their roosts, which include abandoned trees and houses, based on biodiversity and availability of prey. Another hope for the project is to combat negative stereotypes and share bats' significance with the wider community. “Our goal is to help people connect with this really important part of the ecosystem that’s hard to connect with,” Lisette Arellano, a community science manager for One Tam, said. “Bats might end up in someone’s backyard or ranch, and my greatest hope is to be a resource to the community for education about that. I really hope that if they happen to land in someone’s backyard that they feel lucky.” The project has come about as a result of collaborations between U.S.G.S. and One Tam partners, which include California State Parks, Golden Gate National Parks Conservancy, Marin County Parks, Marin Municipal Water District and the National Park Service. “This is not work that any one person can do or any one agency can sustain,” Ms. Arellano said.