When the day changes into night, bats leave their hiding places and come out to feed. Take a stroll through Central Park accompanied by members of the New York City Bat Group including Bradley Klein and Danielle Gustafson, who come equipped with a detector that amplifies the bats’ inaudible chirps, a special bat-watcher's monitor and a species catalogue with which to identify them. You’d be surprised how how many of these elusive creatures call New York City home. R.S.V.P. is required a week in advance. Meetup is at the AMNH entrance on 77th Street between Central Park West and Columbus Avenue. All ages.