Today's mission was to a cave in southwestern Costa Rica, a sea cave, with a bat population of around 800 individuals of three species (all in the Pteronotus genus). There just aren't all that many caves here, so the bats that need caves can really pile into even a small cave that fits their needs.
While we have visited this cave before, this time was mostly just to retrieve a data logger that was placed in the bat roost. No big deal, just go in, get slopped in the guano muck, and get out with the tiny bit of electronics that has been recording atmospheric data for many months.
However...this time the tide was several feet lower than we have ever seen it, and we were able to walk down a beach that was previously pounding waves on a sheer cliff face. To our surprise and good luck, there were more caves.
One was a tunnel that cuts through the rock somewhat parallel to the beach. Beautiful, but not too exiting for bats or other cave stuff.
Probably a bit about this photo is needed here as well. This is Don, holding a CO2 sniffer, below the bat roost. And while it looks like it is snowing, that's not exactly the case here. All those white spots are either fungal gnats or Tineidae moths (no way I can really tell). Fine, but they are attracted to light so a caving headlamp essentially is a great way to attract them into your eyes or up your nose. Such fun.
Otherwise, there were numerous giant cockroaches on the floor and it was raining in the cave. No, not water rain, but just think about standing under 800 small mammals and you get the idea of what was raining down.