Meet Portugal’s Colonies Of Library Bats

Libraries are havens for knowledge. At one library in Portugal, it’s also a haven for bats.

The University of Coimbra is located in Central Portugal, and the library there is also the home to a colony of bats. What’s more, the colony is actually welcome there. So, what would make a university’s library department OK with a colony of bats swooping around priceless editions of 15th-century literature?

The bats serve as the library’s exterminators, eating bugs and helping to preserve the manuscripts on the shelves. The colony at Coimbra is made up of pipistrelle bats and they roost behind the bookshelves. At night, they emerge from the shelves to feed on bugs before flying out of the library windows and out into the town where they find their water sources.

It’s unknown just how long the bats have been there, but the librarians do know that they were there during the 19th century. In fact, the librarians still use the animal skin fabrics from more than 100 years ago to cover the antique tables in the library, protecting them from than animals’ guano. Every morning, the skins are removed and the floor is cleaned.

If you’re interested in seeing the bats you should plan to visit just before sunset and take up a post on the library steps. With any luck, you’ll see the colony emerge from the library and swoop across the town square.


There’s another colony that roosts inside the Library at the National Palace of Mafra, just outside of Lisbon. Experts are unable to say how long the colony has been at this location either, but biologists estimate that they may have been present for centuries.

Like the library at the University of Coimbra, the bats inside the Library at the National Palace come out at night and fly among the stacks of books, many of which go back to the 14th century. Viewing the bats here can be quite a challenge, as the library closes before dark. Some visitors might get lucky and see a few bats swooping among the gardens outside the library. There are a few taxidermied bats on display inside the library.