Coral reef condition in Illana Bay, Zamboanga del Sur, Philippines: Basis for conservation management
Paper Details
Coral reef condition in Illana Bay, Zamboanga del Sur, Philippines: Basis for conservation management
Abstract
Coral reef monitoring is essential for guiding local conservation strategies, particularly in areas exposed to increasing human pressures. This study assessed reef condition in six Marine Protected Areas (MPAs) along Illana Bay, Zamboanga del Sur, southern Philippines, to establish baseline ecological indicators for management. SCUBA-based photo-quadrat surveys were conducted, and benthic composition was quantified using Coral Point Count with Excel extensions (CPCe). Hard coral cover (HCC) differed substantially among MPAs, ranging from 27.60% (San Pablo; Category C) to 45.48% (Dumalinao; Category A). Coral diversity based on Taxonomic Amalgamation Units (TAUs) ranged from 15 to 27 species, with Dumalinao showing the highest richness (27 species; Category A) and Dimataling the lowest (15 species; Category C). Across all MPAs, Acropora branching was the most dominant hard coral sub-category (mean cover = 8.855%), followed by Porites massive (5.093%) and Porites encrusting (4.438%). Shannon diversity index values were low (0.69–1.10), indicating relatively low diversity and uneven community structure. The results suggest that reef assemblages in Illana Bay MPAs remain moderately degraded and are likely influenced by both natural disturbances and persistent anthropogenic stressors. Enhanced enforcement of protective ordinances, targeted community-based interventions, and long-term monitoring are recommended to support reef recovery and resilience.
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Ruel S. Lasagas, Rosanilio M. Yagos*, Edgardo H. Rosales, 2026. Coral reef condition in Illana Bay, Zamboanga del Sur, Philippines: Basis for conservation management. J. Biodiv. Environ. Sci., 28(4), 40-47.
Copyright © 2026 by the Authors. This article is an open access article and distributed under the terms and conditions of the Creative Commons Attribution 4.0 (CC BY 4.0) license.