Although bats are famous for inhabiting caves and rock crevices, no bat caves have been documented in the Yukon. Males and females live separately because of their differing energy needs in summer. Males nest in small groups, hunt at night, and conserve energy by going into torpor, a hibernation-like state, during the day. They need prime habitat and they roost together in large numbers in order to raise the ambient temperature for the young ones. Slough used a bat-detector to find places were bats were living and hunting.
Bats are experts at echolocation - navigating by the use of reflected sound.
Slough says the sounds recorded on the bat-detector indicate when a bat is homing in on an insect. All of the bats Slough located and studied were males living in small groups near water. In the Yukon, bats seem to rely heavily on aquatic insects, he says, so they tend to roost near wetlands or lakes. One goal of the study was to capture and tag bats to find out where they go in winter. Slough used a mist net, a net with very fine strands, which is widely used for capturing small birds.