Investigation of roosting habitat of Artibeus watsoni and Vampyressa nymphaea in Costa Rica

In the spring of 2011, I travelled down to Costa Rica for a semester study abroad program. I had chosen to go to Costa Rica because not only is it a beautiful country but it is also home to a plethora of unique species. This level of diversity can be seen in the approximately 113 species of bats, compared to only 45 species in the United States. One group of bats particularly caught my attention. There are only twenty-two bat species that demonstrate the distinct behavior of modifying leaves to create tents in which to roost (known as tent-making bats). Knowledge of this behavior and preferences of tent-making species is poorly understood, yet crucial to the protection and understanding of species. The objective of this study was to examine the habitat surrounding the tent roosts of Vampyressa nymphaea (Big Yellow-eared bat) in Potalia turbinata plants and of Artibeus watsoni (Thomas' Fruit-eating bat) in Asterogyne plants and to uncover any preferences these species might have. Asterogyne and Potalia plants with and without bat tents were located within Tirimbina Biological Reserve, Heredia, Costa Rica. Habitat measurements were taken on each plant and the surrounding vegetation. Vampyressa nymphaea showed the most selective preference for the height of the plant and the distance to the closest tree. Artibeus watsoni displayed a preference towards height of the plant and canopy cover. Because bats have a highly sensitive and selective attitude towards their habitat, these results may have direct implications on conservation efforts in the tropics.