Overview
The Northern Long-eared Bat (Myotis septentrionalis) is a delicate, agile woodland bat celebrated for its exceptionally large, pointed ears that extend well past its snout when folded forward. A specialized forest-interior hunter, this small insectivore navigates dense forest understories to pluck moths and beetles directly from tree leaves. Tragically, it has become the species most devastatingly impacted by white-nose syndrome across North America.
Biology and Physical Characteristics
Myotis septentrionalis is distinguished from other small myotis bats by its long, pointed tragus and oversized ears measuring 16 to 18 mm. Its fur is medium to dark brown on the back and slightly paler yellowish-tan beneath. Its broad, rounded wings give it exceptional slow-speed flight agility and hovering capability, allowing it to navigate dense forest canopies and hover within centimeters of leaves to glean resting insects.
Behavior and Ecology
Unlike open-air aerial pursuit bats, the Northern Long-eared Bat utilizes foliage gleaning, listening for the faint flutter of insect wings on leaves in addition to emitting high-frequency echolocation pulses. During summer, maternity colonies of reproductive females roost under loose bark or in tree crevices. In autumn, they migrate to deep limestone caves and abandoned mines to hibernate in high-humidity chambers with constant cool temperatures.
Conservation and Human Impact
Federally listed as Endangered under the U.S. Endangered Species Act and assessed as Endangered by the IUCN, Northern Long-eared Bat populations have plummeted by over 97% across their historical range due to the catastrophic fungal pathogen Pseudogymnoascus destructans (white-nose syndrome), which disrupts winter torpor and causes lethal starvation.
Interesting Factoid
The Northern Long-eared Bat has hearing so sensitive that it can detect the microscopic sound of a moth walking across a tree leaf in complete darkness, plucking the prey off the leaf while hovering mid-air.