The Ozark big-eared bat was federally-listed as endangered due to its small population size, reduced and limited distribution, and vulnerability to human disturbance. The entire population currently is estimated to consist of only about 1,800 individuals. The range of the Ozark big-eared bat is limited to northeastern Oklahoma and northwestern and north-central Arkansas.
The Ozark big-eared bat is a unique and fascinating animal. Their ears are over an inch long and they have distinct lumps on each side of their nose. Like other insectivorous bats, Ozark big-eared bats provide important pest control services by nightly eating large quantities of insects. The Ozark big-eared bat is an obligate cave user year round. Many caves considered essential for the continuing existence of the Ozark big-eared bat in Oklahoma occur on the Ozark Plateau National Wildlife Refuge or are managed cooperatively by the refuge but occur on lands owned by private landowners, other agencies, Tribes, or conservation organizations.
Annual monitoring is necessary to help identify factors that may be impacting the species, and to provide information necessary to adequately assess whether current management efforts are effective. The refuge conducts annual emergent counts at Ozark big-eared bat maternity caves using night vision equipment, infrared lights, and video equipment. Video is later reviewed in slow motion and analyzed to improve our ability to estimate the colony size. Characteristics such as large ears help distinguish Ozark big-eared bats from other species.
Monitoring Maternity Colonies of the Endangered Ozark Big-Eared Bat on the Ozark Plateau National Wildlife Refuge Richard Stark, Ozark Plateau NWR
