Of all the species we observed while in Costa Rica, the Common Tent-making Bat (Uroderma bilobatum) might be one of the most ingenious mammals we saw. Certainly, it was one of the most unusual circumstances. We had spent the day in the Manuel Antion National Park craning our necks looking in the upper canopy for any signs of it’s better-known occupants such as the Three-toed Sloth or one of the various monkeys.
It had been a hot muggy day and we were headed back to our rental when we notice a couple peering at the underside of a large banana leaf. I had put away binoculars and cameras and was looking forward to a shower back at the villa. But there was something about the excitement this couple was showing that prompted us to ask what it was they found so intriguing about this leaf. Turns out there were a half dozen Comment Tent-making bats that had constructed a home for the day out of this leaf. So convenient of them to have made it right next to the trail.
Geographic Range: Southern Mexico to Peru and SE Brazil
Habitat: A lowland forest species.
Physical Description: A small phyllostomid, forearm around 42 mm long. Dark grayish brown with a narrow white line down the middle of the upper back, and a distinct white line above and below each eye. No external tail and the tail membrane is narrow and lacks a fringe. The external ears are rimmed with yellow. The upper middle incisors are distinctively bilobed. Dental formula 2/2, 1/1, 2/2, 3/3.
Reproduction: The timing of the reproductive cycle varies seasonally. In Panama, Uroderma breed twice yearly, and birth to correlate with the fruiting and flowering cycle of plants. A single young is born after a gestation of 4 or 5 months.
Behavior: Uroderma roost in groups ranging in size from 2 to 59. They often build “tents” by cutting the structural veins of leaves by chewing parallel to the midrib. The leaves fold down along the midrib, and the bats roost under the resulting “tent.”
Food Habits: Uroderma feed predominately on fruit, but they may take some pollen, nectar, and insects associated with flowers and fruit.
You can read more about the various animals we encountered here. Please your own personal observations or encounters in the comments.