EnglishFrom Kim Williams-Guillén, our director of conservation science:
There are two main lava tube caves, and several smaller caves. The largest cave has a colony of what I believe may be thousands of bats, but we have not done any counts. We have captured five species leaving this cave, Pteronotus parnelli, P. personatus, P. gymnonotus, and P. davyi. On one occasion I caught 3 Mormoops megalophylla which was the first time that species had been recorded in Nicaragua but I have not caught it since then, so I do not know if they were just there “by accident”. All of these bat species are insect eating bats. It is hard to film in that cave, as it is very humid inside (camera lenses fog over) and the bats hide in branches of the cave that are difficult to access, but it is possible to film just inside of the mouth of the cave, or to film the bats emerging from the cave.
The second cave, which is the cave that tourists can enter when with a park ranger, is much more pleasant and dry, but it has relatively few bats. I am not sure if the bats I saw in there were Carollia (fruit eating) or Glossophaga (nectar feeding) bats. There are many areas in and near Masaya where you can spot fruit and nectar feeding bats.