Diverging conservation priorities across New Guinea: Conflicts and opportunities

Conservation planning identifies spatial priorities to guide the allocation of limited resources for safeguarding biodiversity. While New Guinea is widely recognized for its unique ecosystems and endemic biodiversity, the island remains underrepresented in global conservation research. As New Guineas forests face imminent threats from deforestation, a unique window of opportunity has emerged to inform large-scale conservation policies and aspirations for the world’s largest tropical island. In light of these developments, we identified spatial conservation priorities for New Guinea and adjacent islands across eight biodiversity surrogates, assessed their congruence, and outlined conflicts with projected deforestation. We used the following biodiversity surrogates: species composition of terrestrial vertebrates, threatened, endemic, and gap species, species at risk from projected deforestation, functional and evolutionary distinctiveness, and ecoregions. Our results reveal that conservation priorities among them are largely incongruent, demonstrating that focusing on a single surrogate may omit essential conservation priorities for others. This incongruence reflects the complex distribution of New Guinea’s highly range-restricted biota. Achieving adequate representation of all vertebrate species within protected areas would require designating at least two-thirds of New Guinea for conservation. Therefore, short-term conservation efforts should focus on identified irreplaceable priorities at risk from deforestation. Proactive planning should aim to retain large continuous forest landscapes, balancing benefits for both people and nature. A better understanding of the region’s biogeography, alongside studies on global change scenarios and their impact on species distributions and priorities, would greatly benefit biodiversity conservation in New Guinea. For an Indonesian Abstract, see supporting information . • New Guinea emerges as a new deforestation frontier, especially the lowlands. • Conservation priorities for New Guineas biodiversity are not congruent. • Short-term conservation efforts should focus on irreplaceable priorities at risk. • Proactive planning should aim to retain large continuous forest landscapes.