Use of natural and artificial cavities by Neotropical mammals in a tropical wet forest of Costa Rica

Tree cavities are an important ecological component of forests, used by animals for roosting, foraging, hunting, nesting, hiding, and hibernating. However, there has been a taxonomic bias toward investigating cavity use by birds, and a geographical bias toward temperate regions. We used camera traps to understand mammal cavity use in a tropical rainforest. We did so in relation to two contexts: (1) artificial cavity use in early-stage restored rainforest, and (2) natural cavity use of old-growth rainforest. We detected a rich community of 20 mammal species and a single large ground bird around natural and artificial cavities -with 17 and 16 species detected at each cavity type respectively. The community composition around natural cavities was different from that of artificial cavities. The old-growth forest cavity cameras detected a higher species diversity than those in the restoration habitat. Cavity interaction, such as inspecting, foraging, or marking was detected in most species. Animals interacted at similar rates with both natural and artificial cavities, but utilized each type differently. Our baseline assessment provides key insights on tropical rainforest mammals as cavity users which revealed a high diversity representative of 80% of the terrestrial medium to large mammal reported for the region. As Neotropical secondary forests lack some key structural components found in old-growth forests, proactive approaches to actively restore such features could be a management tool in restoration efforts to speed up faunal recovery. Even so, further research is needed to fully disentangle as to whether the different associated communities and use patterns are an effect of the mammal community in the surrounding habitats or due to differences in the cavities themselves, likely due to artificial vs natural materials.