Tropical rainforests are the most biodiverse terrestrial ecosystems on Earth, home to over half of the world’s vertebrate species. Reducing tropical deforestation is the cornerstone of biodiversity conservation efforts. However, this focus on retaining forest cover ignores the multitude of human pressures that can operate to degrade the quality of that cover in ways severely detrimental to biodiversity. We use the latest remotely-sensed measures of forest structural condition and associated human pressures across the global humid tropics to provide the first estimates of the importance of forest quality, relative to forest cover, in mitigating extinction risk for tropical rainforest vertebrates worldwide. We found that tropical rainforests of intact structural condition and minimal human pressures were associated with significantly lower odds of species being threatened or having a declining population when contrasted with forest cover. Further, the effects of forest quality in mitigating extinction risk were amplified when small amounts of forest remained within species geographic ranges, as opposed to when large extents within species ranges were forested, suggesting that small, remnant rainforest patches are important for biodiversity. Our work demonstrates a critical need to refocus conservation strategies toward preserving and restoring forest quality, as opposed to maintaining forest cover alone.

The Natural Resources & Environmental Studies Institute (NRESi) at UNBC hosts a weekly lecture series at the Prince George campus. Anyone from the university or wider community with interest in the topic area is welcome to attend. Go to http://www.unbc.ca/nres-institute/colloquium-webcasts to view the presentation remotely.

Past NRESi colloquium presentations and special lectures can be viewed on our video archive, available here.