Mammalogists use live traps, mist nets and even firearms to capture and restrain wildlife for study. The tools used depend largely upon the size of the study species.
Mammalogists studying small mammals use small live traps to capture the animals. A live trap typically consists of a cage-like container with a door and a lever or pedal. Placing appropriate bait on the pedal entices the animal to step on it, tripping the doors. Mammalogists place live traps on the paths that small mammals use to travel throughout a habitat.
Mist nets are essential tools for capturing bats. These fine black mesh nets are placed along bats' flight paths. Bats don't echolocate while traversing flight paths and readily fly into the nets.
Mammalogists also use firearms to fire both tranquilizer darts and nets, usually to capture larger species. Tranquilizers require a degree of calculation, as the dosage must be sufficient to keep the animal down but not potent enough to harm it. A net gun can be used on foot or from aircraft. Some mammalogists use large, barrel-like live traps for larger animals such as coyotes or bears.
Mammologists also use tools for collecting data, including capture bags for restraining wildlife and various scales and measuring equipment for collecting physical data on an animal.