Use of species’ responses to cryptic anthropogenic disturbances for monitoring biodiversity outcomes in tropical forests

TL;DR

This study compares biodiversity in a community-managed forest and a protected area in Guatemala, finding that human access affects species differently.

Contribution

The study introduces a method using multispecies occupancy models and camera trapping to assess cryptic human impacts on biodiversity in tropical forests.

Findings

Species richness and mean community occupancy were similar between community-managed and protected areas.

Human access had a stronger effect on species occupancy than other habitat variables.

Cryptic disturbances influence species distribution, suggesting the need for improved biodiversity monitoring methods.

Abstract

Measuring area‐based conservation outcomes in tropical forests is challenging due to cryptic human disturbances (e.g., hunting). As a result, comparative studies of management strategies providing quantitative outcomes remain scarce, especially in the Neotropics. We compared species distribution and richness of terrestrial wildlife in a community‐managed forest and a strictly protected area in Guatemala's Maya Biosphere Reserve. Using multispecies occupancy models and a spatially extensive camera‐trapping grid, we assessed how species respond to structural habitat variables (e.g., elevation, forest canopy height), protection, and human access, a proxy for hunting and cryptic resource use (i.e., human activities that occur under the forest canopy) by nearby communities. During 2018–2019, we recorded 26 terrestrial vertebrate species of >1 kg. We found no differences in species richness or mean community occupancy (i.e., average occupancy probability of all species in the community) at the community level between the community‐managed forest and the protected area. For some species, the effects of human access on occupancy were larger than the combined effects of all other habitat variables. In the community‐managed forest, ease of human access negatively influenced the occupancy of tapirs (Tapirus bairdii) and hunted species, such as the great curassow (Crax rubra), ocellated turkey (Meleagris ocellata), and white‐lipped peccary (Tayassu pecari). Small and more generalist species were positively affected by ease of access, possibly reflecting trophic release near human settlements. Although large carnivore occupancy was not affected by access in the community‐managed forest, low detection probabilities could reflect density or behavioral changes. These findings illustrate the influence of cryptic disturbances on some species’ distribution in intact forests and suggest that management actions in the community‐managed forest may have helped maintain diverse assemblages. Our study suggests the need to go beyond remotely sensed measures and species richness metrics when assessing and monitoring biodiversity outcomes in tropical forests.

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