Morphology, abundance and population status of flying foxes in the mangrove ecosystem of Barangay Bukid, Jose Abad Santos, Davao Occidental, Philippines
Paper Details
Morphology, abundance and population status of flying foxes in the mangrove ecosystem of Barangay Bukid, Jose Abad Santos, Davao Occidental, Philippines
Abstract
Flying foxes (Pteropus spp.) are keystone pollinators and seed dispersers whose populations are increasingly threatened by habitat degradation and human disturbance. This study assessed the morphology, abundance, population status, and habitat associations of flying foxes in the mangrove ecosystem of Barangay Bukid, Jose Abad Santos, Davao Occidental, Philippines, to provide baseline information for conservation planning. Field investigations conducted from January to June 2025 employed roost-site surveys, direct observations, photographic documentation, acoustic monitoring, and vegetation assessment. A total of 11,920 flying foxes were recorded, comprising 10,955 Island flying foxes (Pteropus hypomelanus) and 965 Large flying foxes (Pteropus vampyrus), roosting on 626 mangrove trees within a 962-m² area. Nine mangrove species were identified, with Rhizophora mucronata, Sonneratia alba, and Rhizophora apiculata exhibiting the highest Importance Value Indices, indicating their dominant role in supporting communal roosts. The mangrove forest exhibited moderate species diversity (H′= 1.962) and high evenness (J′= 0.893), indicating a structurally stable habitat conducive to sustaining mixed-species colonies. Field observations further indicated active reproduction, preference for mature Rhizophora stands, and sensitivity to anthropogenic disturbance, emphasizing the ecological dependence of flying foxes on intact mangrove ecosystems. The presence of a large mixed colony, including the nationally threatened P. vampyrus, highlights the exceptional conservation value of Barangay Bukid. These findings provide strong scientific evidence for declaring the area a Critical Habitat and underscore the need for long-term protection and sustainable management of its mangrove ecosystem.
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