Daubenton’s Bat (Myotis daubentonii), is a Eurasian bat that ranges from Britain to Japan and is considered to be increasing its numbers in many areas. The bat is mostly found in woodlands and always chooses roosts close to water sources such as rivers or canals. Summer colonies are formed in underground caves, tunnels, cellars, mines, and underneath bridges. These colonies are also always near water. Daubenton’s Bat also hibernates in the same type of locations from September to late March or April.
Daubenton’s Bat is a medium sized to small species. The bat’s fluffy fur is brownish gray on the back and silvery grey on the underside. Juveniles have darker fur than adults. The bats have reddish pink faces and noses, but the area around the eyes is bare. When the bat is agitated, the ears are held at right angles. Daubenton’s Bat is typically 1.75 to 2.25 inches long, with an average wingspan of 9.5 to 10.75 inches. Daubenton’s Bat weighs between 0.25 and 0.55 ounces.
Daubenton’s Bat is insectivorous and uses echolocation to find prey and orientate itself at night. Bats emit sounds too high in frequency for humans to detect and interpret the echoes created to build a “sound picture” of their surroundings. The bats emerge at twilight to hunt for insects over the water. Their main diet consists of small flies, midges, mayflies, and moths. Daubenton’s Bat often eats its prey while still in flight.
Mating occurs in autumn and fertilization takes place the following spring. Females gather in maternity colonies of 40 to 80 bats during the summer months. Daubenton’s Bat is able to fly three weeks after birth and reaches independence at 6 to 8 weeks of age.
The name commemorates the French naturalist Louis-Jean-Marie Daubenton.