Comparative Assessment of Sea Krait Encounter Density in Pinyahon Islet, Sibutad: Ecological and Science Education Implications

Abstract

Coastal habitat modification and increasing shoreline development may influence the site use and encounter density of amphibious sea snakes such as sea kraits (Laticauda spp.). This study conducted a comparative assessment of sea krait encounter density in Pinyahon Islet, Sibutad, Zamboanga del Norte, using a Visual Encounter Survey (VES) performed in 2026 and baseline density data from 2011–2013 for the same 0.40-hectare shoreline area. A total of seven individuals were recorded across three standardized night surveys in 2026, dominated by Laticauda colubrina (71.43%) and followed by Laticauda laticaudata (28.57%). Comparative analysis indicated a substantial reduction in encounter density relative to baseline estimates, particularly for L. colubrina. All observed individuals were restricted to non-cemented rocky microhabitats, with no sightings in cemented shoreline sections. Key Informant Interviews provided contextual insights regarding historical abundance, perceived habitat changes, and site conditions. While causality cannot be definitively established due to methodological constraints, the convergence of quantitative and qualitative findings suggests reduced site-level encounter density associated with habitat structural change. The results highlight the ecological importance of shoreline microhabitat complexity and provide locally grounded evidence that may inform coastal management considerations and science education initiatives aligned with Sustainable Development Goal 14 (Life Below Water). Continued monitoring is recommended to clarify long-term population trajectories and habitat-use dynamics.