Drivers of extinction risks and shortfalls across terrestrial vertebrates in the Philippine global biodiversity...

The Philippines is a biodiversity hotspot with a rich variety of terrestrial vertebrate species, many of which are endemic and threatened by environmental changes and unsustainable human activities. Effective conservation actions are urgently needed; however, progress towards it is often hampered by persistent knowledge shortfalls and uneven research efforts for many species and habitats. Using standardised data from the IUCN Red List and GBIF, we assessed extinction risks, threats, and knowledge shortfalls of 1, 294 extant terrestrial vertebrate species in the Philippines. We found that between 15% to 23 % of the species are at risk of being threatened by extinction, particularly endemic amphibians and mammals, likely driven by habitat loss, overexploitation, and a combination of other threats. Reptiles remain markedly underrepresented in research and their true threat status is likely underestimated. Our findings highlight the historical research biases leading to conservation inequities, leaving vulnerable and data-deficient species and areas overlooked. Filling these gaps with balanced and appropriate research investments, expanded monitoring, and improved data sharing are crucial for evidence-based conservation. We recommend the use of integrative tools and remote sensing to address the major biodiversity shortfalls in the Philippines. The integration of collaboration, citizen science, targeted surveys, and genetic research can address these data gaps. Our study offers a strategic framework for guiding national conservation priorities and safeguarding the country's rapidly vanishing wildlife heritage, emphasising that, without informed action, the Philippines risks losing its unique biodiversity.