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Biology subjects

Senarillos, T. L. P.

Publications and source records attributed to Senarillos, T. L. P..

2 recordsLinked to original sources

Directing conservation action for the Critically Endangered Philippine Eagle to mitigate mining impacts and maximize indigenous land management

As habitat destruction intensifies due to expanding human infrastructure, balancing biodiversity conservation with resource extraction has become a global challenge. Thus, quantifying the extent and location of proposed mining operations is key to mitigating the impacts on threatened species. This issue is particularly acute in the biodiversity hotspots of southeast Asia, where rapid economic growth needs to be balanced with sustainable conservation management of the remaining tropical forest. The Philippine Eagle (Pithecophaga jefferyi), a critically endangered tropical forest raptor endemic to the Philippines, faces increasing threats from mining activities that destroy and fragment its tropical forest habitat. Here, we integrate Species Distribution Modelling with gap and hotspot analysis to assess the spatial overlap between Philippine Eagle nest habitat and mining concessions across a protected area network on Mindanao, where the largest population remains. Using a landscape-scale SDM built with remote sensing covariates and eagle occurrence data, we identified high-suitability nest habitats and projected these into the Eastern Mindanao Biodiversity Corridor (EMBC). Hotspot analysis revealed that 41 % of the total mining concessions area contained high-suitability nest habitat, highlighting significant conservation risks. Additionally, 46 % of indigenous ancestral domains contain high-suitability nest habitat, emphasizing the importance of indigenous land management in safeguarding eagle habitats. Our gap analysis demonstrated that 35 % of the EMBC protects high-suitability nest habitat, which here represents the remaining montane tropical forest. To mitigate mining impacts, we propose targeted nest surveys in high-risk areas, implementation of mining moratoriums near critical nesting zones, and strengthening indigenous and protected area land management. By integrating SDMs with spatial analysis, we provide a framework for directing conservation efforts to balance resource extraction with the preservation of the Philippine Eagles habitat. Our findings offer crucial insights for policy development and land-use planning to protect this iconic species and its threatened habitat.

ecology↗

Space-time home range estimates and resource selection for the Critically Endangered Philippine Eagle on Mindanao

Quantifying home range size and habitat resource selection are important elements in wildlife ecology and are useful for informing conservation action. Many home range estimators and resource selection functions are currently in use. However, both methods are fraught with analytical issues inherent within autocorrelated movement data from irregular sampling and interpretation of resource selection model parameters to inform conservation management. Here, we apply satellite telemetry and remote sensing technologies to provide first estimates of home range size and resource selection for six adult Philippine Eagles (Pithecophaga jefferyi), using five home range estimators and non-parametric resource selection functions. From all home range estimators, the median 95 % home range size was between 39-68 km2 (range: 22-161 km2), with the 50 % core range size between 6-13 km2 (range: 5-33 km2). The space-time autocorrelated kernel density estimate (AKDE) had the largest median 95 % home range size = 68 km2 and a 50 % core range = 13 km2. Local convex hulls (LoCoH) estimated the smallest median 95 % home range = 39 km2 and a 50 % core range = 6 km2. From the resource selection functions, all adults used areas high in photosynthetic leaf and canopy structure but avoided areas of old growth biomass and denser areas of vegetation, possibly due to foraging forays into fragmented areas away from nesting sites. For the first time, we determine two important spatial processes for this Critically Endangered raptor that can help in directing conservation management. Rather than employing a single home range estimator, we recommend that analysts consider multiple approaches to animal movement data to fully explore space-time and resource use.

ecology↗