Today, 17th of April, is International Bat Day.

Most European bat species use woodlands at some point in their lives, whether for hunting, hibernation, breeding, temporary shelter, etc.
Many species are intimately associated with forests throughout the year, as they exclusively or mainly use tree hollows for shelter, and to a greater or lesser extent, obtain food in forests.
These are what we call arboreal or strict forest bats. We can consider up to 10 species within this group.
An excellent document, in Spanish, with a lot of information about forest bats can be found here.

Myotis cf. nattereri - Photo Jordi Bas

Myotis cf. nattereri – Photo Jordi Bas

If you want to know more about bats in Spain, visit the website of the Spanish Association for the Conservation and Study of Bats.