Other obvious hymenopterans at our field site include the eusocial wasps of the family Vespidae. Sure, in the temperate regions we have our hornet nests and paper-wasp nests, but these types of wasps really become conspicuous in the tropics. There are just so many more elaborate mud and paper domiciles hanging about trees, bushes, and buildings built by a number of interesting genera that are sadly missing from higher latitudes. In fact on one cool day, when few insects were flying about, I took the opportunity to collect these nests and their occupants.
We occasionally noticed a bat flying around our lab space but didn’t pay too much attention to it. On our last night however, when it was unseasonably cold, several bats decided to use our lab as shelter. Often when the door opened one would fly in and around and then perch underneath one of our lab benches; five in fact were roosting together there at one point. I didn’t think too much of it until I recalled that bats have some pretty bizarre fly parasites that wander about through their fur. Suddenly this became an opportunity to make a novel entomological find.
A very nice colony of oropendola birds was nesting outside our lab. We became accustomed to their comings and goings and admired their long, basket-like nests and gargling calls. They always seemed to come and go together and did so with much fanfare. One afternoon however, while the birds were away, three capuchin monkeys raided their nests, and we were lucky to see it. The capuchins systematically went to each one, inserted their heads and torsos into the long nests, pulled out the oropendola eggs, and ate them right there in front of us. It was quite shocking.