Did you know that one of Europe’s largest bat species is silently working through the night, protecting our ecosystems? The Myotis myotis, commonly known as the Greater Mouse-Eared Bat, is a true nocturnal hero.
Key Facts:
Wingspan: up to 40 cm | Weight: 25-40 grams | Lifespan: up to 20 years in the wild| Diet: Ground-dwelling insects like beetles, spiders, and even centipedes!
Unlike most bats, Myotis myotis hunts by “gleaning”—they don’t catch insects in the air but instead listen for the tiniest rustle on the forest floor and swoop down to snatch their prey. Their large ears give them extraordinary hearing, allowing them to detect movements in total darkness.
Preferred habitats (habitats in Romania & Ukraine)
- Roosts: underground sites—caves, mines, cellars predominantly, used for both hibernation and summer shelters across its range eurobats.org+1ResearchGate+1.
- In Romania: large cave systems at mid-elevations (~300–600 m a.s.l.) host significant winter colonies; breeding colonies similarly found in thermally suitable caves or large roof-spaces in western and southwestern Romania econsult.ecoedu.ro
- In Ukraine: only underground sites have yielded sightings; there is no evidence of maternity colonies yet Bat Conservation Trust+1econsult.ecoedu.ro+1.
- Foraging habitat: open deciduous or mixed woodlands, forest edges, pastures, meadows and lightly wooded farmland, where ground‑dwelling prey is abundant Wikipedia+1eurobats.org+1.
Life periods: seasonal cycle & reproduction
- Spring/autumn movements: In Romania and Ukraine, bats arrive at summer roosts in mid‑April to May and depart as autumn temperatures drop, often swarming in caves in late August for mating and dispersal.
- Maternity colonies: In Romania, females form large summer nursery colonies, often from May to August. Birth occurs late May to early June, occasionally as early as April in Mediterranean‑like zones; young begin flying around early July, roughly 3–4 weeks after birth BatsLife | aplr.ro
- Hibernation: Bats aggregate in underground sites during winter months (roughly November to March). In Romania, aggregations of Myotis myotis commonly occur alongside M. oxygnathus, sometimes in clusters of thousands in major cave systems (~Apuseni Mountains) Bat Conservation Trust
Summary Table
| Region | Presence | Roosts (hibernation| summer) | Foraging Habitat | Reproductive Period |
|---|---|---|---|---|
| Romania | Widespread in several karst zones | Caves (mid‑altitude ~300–600 m), occasional roofs | Open woodlands, edges, pastures | Births late May–early June; juveniles flying in July |
| Ukraine | Western Dniester subregion only; rare singles | Underground only; no maternity colonies confirmed | Likely similar wood/open habitats | Breeding not confirmed; hibernation occurs in caves |
Why Should We Care?
Bats like Myotis myotis play a vital role in maintaining healthy ecosystems. By controlling insect populations, they reduce the need for chemical pesticides and help preserve biodiversity.
Let’s celebrate these amazing creatures and support efforts to protect them!
Have you ever spotted a bat at night? Share your experience in the comments!