Eastern Small-footed Myotis

Fascinating facts about the Eastern Small-footed Myotis

• A single Eastern small-footed myotis weighs less than a penny — roughly 3 to 5 grams — yet hunts with surgical precision using echolocation clicks that bounce off insects smaller than a grain of rice. Their calls shift frequency mid-hunt, speeding up from 10 clicks per second to 200 as they close in, a biological sonar system that hasn't been fully replicated by human engineers.
• When winter arrives, these bats enter torpor so deep their heart rate drops from 400 beats per minute to just 10, and their body temperature plummets to match the cave wall they cling to. They can survive months without food or water by living as near-living statues, yet they're vulnerable to a fungus called white-nose syndrome that wakes them during hibernation, burning through their energy stores until they starve.
• Eastern small-footed myotis have fur so fine it refracts light into iridescence — some individuals glow bronze or chestnut depending on the angle, a feature so subtle it went unnoticed for decades. This wasn't vanity: the colour variation tracks geographic populations, helping scientists map migration routes across the Appalachians and beyond.
• Females give birth to just one pup per year in late spring, an unusually small litter for mammals — most give birth in the summer heat when insects are abundant, timing their pregnancy to match the peak of their food supply. A mother's lactation demands mean she must catch roughly double her body weight in insects every single night, a metabolic feat that leaves no room for bad hunts.
• Today, fewer than 11 states east of the Mississippi have stable populations, and they've vanished from historic ranges across New York and New England in under a decade. White-nose syndrome killed an estimated 5.7 million North American bats in the last 15 years, but Eastern small-footed myotis have proven slightly more resistant than their cousins — a survival quirk scientists are racing to understand before the species tips toward extinction.

At a glance

About the Eastern Small-footed Myotis

In the fading light of dusk, the Eastern Small-footed Myotis takes to the skies, its delicate wings beating in a hypnotic rhythm as it navigates the labyrinthine corridors of forest and woodland with ease. With echolocation calls that pierce the evening air, this tiny, endangered bat probes the shadows for the insects that sustain it, its very existence a testament to the intricate web of life that binds our planet together. As it flits and weaves through the darkness, its small form silhouetted against the moon, the Eastern Small-footed Myotis embodies the quiet resilience of a creature fighting to survive in a world that often seems determined to forget it.

Discover more wildlife