We studied roost structure, modification, and availability in Lophostoma silvicolum (Phyllostomidae), an insectivorous gleaning bat, on Barro Colorado Island (BCI),Panamà. Collection of nest material beneath termitaria and infrared video filming indicated that males of L. silvicolum excavate and maintain cavities inside active
termite nests. A binary logistic regression analysis showed that to be suitable as roosts, termite nests have to be larger than 30 cm in diameter and taller than 30 cm,
well shaded, with few transecting branches, and freely accessible from below. Use of active termite nests as roosts may provide several benefits to L. silvicolum, including
reduction of competition for roost sites with sympatric bat species, reduced parasite load and a suitable microclimate. A comparison of number of all termite nests in selected forest plots with number of termite nests that are potentially suited as bat roosts and number of termite nests that are actually used by bats suggests that L. silvicolum may not be roost-limited on BCI in spite of its highly specialized roost choice.