Geoffroy’s Myotis

Identification

Geoffroy's myotis, also known as the notch-eared bat, is a medium-sized vesper bat distinguished by its long, woolly fur. Adults display rust-brown to fox-red coloring on their dorsal side, contrasting with a poorly delineated pale yellowish-brown ventral surface, while young animals are almost fully grey. The face is light brown, and the most distinctive feature is the ears: brown with an almost right-angled notch at the outer edge and many scattered, wart-like growths on the auricle. The tragus tip does not reach the notch. The bat has broad brown wings and a tail membrane supported by a straight calcar with short, straight, and soft hairs along its edge.

Range & Habitat

Geoffroy's myotis has an extensive range across Eurasia, from western Europe through the Mediterranean and into Central Asia, occurring in over 40 countries from Afghanistan to Portugal and from Germany to Oman. A remarkable 2012 sighting in southern England marked an unusual northern occurrence. The species shows habitat flexibility across its range: in Iberia it favors broad-leaved and mixed forests and Mediterranean olive plantations; in northwestern populations it frequents riparian forests and grasslands; and across its range it commonly roosts in underground sites and human buildings, often alongside Rhinolophus species. It also regularly visits cattle sheds, attracted to parasitic fly populations.

Behaviour & Diet

Geoffroy's myotis is a specialized insectivore with a diet dominated by spiders and flies. The bat employs a gleaning strategy, foraging by plucking prey from hard surfaces and leaves rather than catching insects in flight—a behavior reflecting its preferred prey of flightless spiders and non-nocturnal muscid flies such as stable flies and face flies. Regional diet varies seasonally and geographically: in southern Belgium, blood-feeding muscid flies constitute up to 72% of intake, while in southern Basque Country, web-building spiders—particularly the orb-web spider *Araneus diadematus*—can comprise 80% of diet by August. The bat's preference for dense habitats is driven by its dependence on complex vertical structures where web-building spiders construct their webs.

Best Time & Places to See It

Observers seeking Geoffroy's myotis should focus on suitable habitats within its broad Eurasian range. In Mediterranean regions, olive plantations offer reliable viewing opportunities. Northwestern European populations are best encountered near riparian forests, grasslands, and cattle sheds—the latter particularly productive for observing feeding activity. The species is nocturnal, so night surveys using bat detectors or emergence watches at known roosts (caves, buildings, and underground sites) are most effective. Regional diet composition suggests that areas with abundant spider webs and muscid flies will attract feeding activity.

Photography Tips

Photographing Geoffroy's myotis presents considerable challenges due to its small size, nocturnal habits, and fast, maneuverable flight. High-speed flash equipment and infrared triggers are essential for capturing sharp images. Focus on roosting sites such as caves, church lofts, and cattle sheds during daytime, where the bat's distinctive notched ears and woolly fur texture can be documented without disturbance. Emergence photography at dusk requires fast film speeds and anticipatory positioning. The bat's preference for gleaning close to surfaces and vegetation means that foraging observations may occur near ground level or within complex forest structure, offering opportunities for behavioral documentation.