• J. Woken

Myotis: Little or Long-Eared?

In retrospect, I should have named him Otis. He was, after all, "my-otis", if only for a night.

The little brown bat somehow tumbled into our living room around 11 o'clock. I was first alerted to an intruder by our cat, who darted off the bed in pursuit of fun. A few minutes later, a hollow scratching sound urged me out of bed to investigate for myself. Luckily, tracking the noise was easy: The bat had somehow managed to trap itself into the upside-down cone-type shade of our living room's floor lamp! With my hands protected in two very heavy oven mitts, I scooped the little guy into a clean glass jar and attached the lid. Back to bed I went.

A little brown bat rests peacefully in his temporary confinement. / J. Woken

Upon inspection the following morning, I found the bat to be a healthy specimen (and, by now, a sleepy one). His coat was a shiny brown and his wings, toes, and ears were undamaged and intact. I was thankful to see this little guy wasn't showing any outward signs of white-nose syndrome (WNS), a fungal disease responsible for killing millions of bats across the northeast.

Bats are fascinating creatures. Aside from being the only truly flying mammal (as opposed to the flying squirrel, which merely glides for long distances), of the over 1,000 species around the world, three species feed solely on blood (true vampire bats, though none live in the U.S.) and some bat species live for over 20 years.

Minnesota's most common bat, the Little Brown Bat's scientific name is Myotis lucifugus. Myotis means "mouse-eared" and it's easy to see why the Little Brown gets the name. Little brown bats are considered microbats (of the scientific Order, microchiroptera), which have a few discerning features from their megabat (Order: megachiroptera) relatives. For us bat novices, here's the easier distinctions: microbats are generally smaller in size, with relatively tiny eyes and big ears; megabats are larger overall, with big, protruding eyes and smaller ears.[i]

Little brown bats live an average of 6.5 years while the Northern long-eared bat can live up to 18.5 years, near the max of all bat species.

Bats are a mixed blessing. On one hand, they're incredibly handy to have around. They can eat up to three times their own weight in insects (like mosquitoes!) each night. If you're a fan of sonar and radar navigation and tracking systems, you should thank a bat: Scientists' discovery of bats' echolocation (using sound to navigate by tracking the echos of those sound waves) "led to development of sonar and radar by which boats and planes navigate, and fishermen locate schools of fish."[ii]

Bats can eat up to 3x their weight in insects per night and are the inspiration behind today's sonar and radar systems.

On the other hand, bats have a tendency to be pesty. They commonly roost in buildings, where their droppings (guano) and urine -- which are high in concentrations of corrosive uric acid -- eat away at insulation, wires, nails/screws, drywall, and wood framing. Bats are the "perfect hosts' for many disease-causing viruses, including rabies, Ebola, and even the hot-topic virus of the day, Coronavirus.[iii]

Despite health and home dangers, bats remain a protected animal in the United States. It's illegal to kill them or keep them as pets. In light of that knowledge, I released Otis the following day when temperatures rose to fly away and find a new perch (or re-enter his old one (i.e. our attic)), per the suggestion of PennState Extension.

Now, I'm on task to contact a local Wildlife Management crew to inspect our home and subsequently deal with our unwelcome guests via exclusion (NOT extermination!). As hands-on as I like to be with and in the local wild, I'll leave the bat-related business to the professionals.


[i] "The differences between megabats and microbats", Virginia Bat Pros, 05Jan2018. URL: Accessed: 18Feb2020.

[ii] "Bats", Minnesota DNR. URL: Accessed: 18Feb2020.

[iii] Sanicas, Melvin (Dr.), "What makes bats the perfect hosts for so many viruses?". Healthcare in America, 28June2018. URL: