Human population growth threatens the largest and only protected key biodiversity area in Cebu Island
Research & Innovation | July 27, 2023
The continuing pressure on the natural environment exerted by human activities such as land conversion has been threatening to drive tens of thousands of species to extinction globally for decades. Species conservation requires identifying species ranges impacted by threats, which helps predict potential localized extinctions. This paper assessed the human pressures that threaten the local biodiversity in Cebu Island, Philippines, to help prioritize actions to manage and mitigate human impact on local biodiversity. Hotspots, where modeled tree species richness is compromised, were identified through an overlay of several human pressure variables (i.e., human population and building density, electric infrastructures, navigable waterways, roads, croplands, grasslands), and soil erosion. A notable observation from the study was that the largest and only protected key biodiversity area (KBA) – the Central Cebu Protected Landscape (CCPL) – had the highest percentage occurrence of medium to high threats within its boundaries, which could be attributed to its proximity to highly populated municipalities and cities. More importantly, possible areas of refuge for key species were identified. These areas could be appropriated as local restoration sites by the local government units of Mt. Lanaya and Nugas forest in the south of Cebu since these KBAs have high tree species richness but with less occurrence of high threats. The resulting maps could also be used as important references for targeted conservation management programs to help mitigate the threats that are driving local species to their decline and for preemptive planning of local and national conservation agenda.
The acquired results present an opportunity to pinpoint which areas within the KBA need more management attention for the conservation of the threatened endemic species like the black shama, Cebu hawk owl, Cebu flowerpecker, Cebu cinnamon, and Cynometra cebuensis. Initiating steps to legalize the protection of these biologically rich, yet unprotected KBAs before urbanization sets in can buffer the negative impacts of the tradeoff between economic development and environmental protection. In the case of the lone protected KBA in Cebu Island, the CCPL’s rocky relationship with commercial development while upholding its strict environmental protection zones continues to be complicated for all stakeholders. Preventing this scenario to occur in the other KBAs will benefit all stakeholders. Rich and biodiverse ecosystems (such as forest ecosystems) mean the continuous supply of ecosystem services (e.g., fresh air, fresh water, food, fiber) to human communities. Prioritizing conservation initiatives in these biodiversity hotspots that serve as the last bastions of rich biodiversity in Cebu Island must be made, especially in areas considered as possible refugia for our endemic species because of low threat occurrence. Efforts to restore the island’s denuded forests and connect the forest fragments should be continued to help these ecosystems serve their regulating functions, such as the reduction of flooding or the increase in water recharge.
Read the full paper: https://philjournalsci.dost.gov.ph/publication/special-issues/biodiversity/104-vol-150-s1/1369-mapping-hotspots-of-human-impact-on-native-dendroflora-biodiversity-in-cebu-island-philippines