Overview
Davy’s Naked-backed Bat (Pteronotus davyi) is an extraordinary neotropical mormoopid bat distinguished by an evolutionary innovation that makes its back appear completely hairless and bare. Widely distributed across Mexico, Central America, and northern South America, this agile flyer roosts in colossal colonies deep inside hot, humid limestone caves. Emerging at twilight in synchronized clouds, it darts through the forest subcanopy with exceptional aerobatic speed, vacuuming nocturnal insects directly from mid-air.
Biology and Physical Characteristics
Despite its common name, Davy’s naked-backed bat is not actually hairless; rather, its wing membranes (plagiopatagia) meet and fuse along the dorsal midline of its spine, covering its densely furred back with a smooth, glossy skin surface. Beneath this membrane lies a layer of velvety brown to cinnamon fur. This dorsal wing attachment significantly increases effective wing surface area, dramatically enhancing aerodynamic lift and maneuverability during high-speed low-altitude foraging. Its lower lip features an ornate plate-like skin flap, which functions in directing echolocation pulses emitted via its open mouth.
Behavior and Ecology
Pteronotus davyi is an obligate cave dweller that roosts in deep, structurally complex subterranean caverns, frequently sharing roosts with thousands of other bats in microclimates where temperatures exceed 30°C and humidity approaches saturation. Using high-frequency constant-frequency (CF) and frequency-modulated (FM) echolocation calls, it navigates complex forest vegetation with pinpoint accuracy. It hunts primarily for soft-bodied Lepidoptera (moths) and Diptera, consuming up to half its body weight in insects every single night. Females bear a single pup per year during the onset of the rainy season.
Conservation and Human Impact
The IUCN classifies Pteronotus davyi as Least Concern due to its vast geographic distribution and high local abundance. However, because thousands of individuals congregate in a relatively small number of specialized cave systems, colonies are exceptionally vulnerable to vandalism, cave tourism, guano mining, and roost entrances being sealed by landowners. Protecting critical karst landscapes and implementing bat-friendly cave gates are key priorities for safeguarding major roost sanctuaries.
Interesting Factoid
The naked-backed bat’s wings fuse completely over the center of its spine, creating an unbroken hydrodynamic skin surface across its back that gives it far higher flight lift than almost any other bat of its size.
Last updated: October 2026