Mon, Aug 02, 2021:On Demand
Background/Question/Methods
Tropical forests contain disproportional amounts of the world’s biodiversity, but are being lost at rapid rates. At the same time, our ability to gauge how tropical species are responding to sources of global change is drastically hampered by lack of knowledge. There is an urgent need for greater understanding of the status of tropical species and their responses to anthropogenic impacts so that conservation efforts can be targeted accordingly. We present the second pantropical analysis of community-level trends for mammals and birds at 16 sites throughout the tropics using systematic, standardized annual camera trap surveys of more than 500 populations monitored by the Tropical Ecology Assessment and Monitoring (TEAM) Network. To assess changes in terrestrial vertebrate biodiversity over time, we used a dynamic multispecies occupancy model. This approach accounted for variability in detection within and between species.
Results/Conclusions We found significant declines in tropical forest birds within the majority of monitored protected areas; no protected areas had significant bird increases. Tropical forest mammals declined significantly in two protected areas while one protected area had significant mammal increases. We assessed these results in the context of land use change and hunting pressure. These results provide quantitative evidence of the extent of tropical vertebrate defaunation within protected forests that has heretofore been described as a cryptic phenomenon. This research expands upon previous results that documented negative relationships between intensive human land used and species richness, species diversity and functional diversity in a subset of TEAM Network sites. Protected areas in the tropics have suffered less deforestation than their immediate surroundings, yet deforestation outside of protected areas may reduce their capacity to protect biodiversity. Our data-driven results based on systematic monitoring support conclusions based on expert opinion that the effectiveness of tropical protected areas is linked to environmental conditions outside protected areas.
Results/Conclusions We found significant declines in tropical forest birds within the majority of monitored protected areas; no protected areas had significant bird increases. Tropical forest mammals declined significantly in two protected areas while one protected area had significant mammal increases. We assessed these results in the context of land use change and hunting pressure. These results provide quantitative evidence of the extent of tropical vertebrate defaunation within protected forests that has heretofore been described as a cryptic phenomenon. This research expands upon previous results that documented negative relationships between intensive human land used and species richness, species diversity and functional diversity in a subset of TEAM Network sites. Protected areas in the tropics have suffered less deforestation than their immediate surroundings, yet deforestation outside of protected areas may reduce their capacity to protect biodiversity. Our data-driven results based on systematic monitoring support conclusions based on expert opinion that the effectiveness of tropical protected areas is linked to environmental conditions outside protected areas.