Diversity and Distribution of Marine Gastropods in the Subtidal Zone of Hutumuri Waters, Ambon, Indonesia

Abstract

Marine gastropods are important components of tropical benthic ecosystems, and their assemblages can provide information on habitat conditions. This study assessed the species composition, ecological density, abundance, frequency of occurrence, community structure, and bathymetric distribution of marine gastropods in the shallow subtidal zone of Hutumuri Village, Ambon Island, Indonesia. Sampling was conducted from February to April 2026 along six transects established perpendicular to the shoreline and separated by 100 m. Gastropods were recorded in 5 × 5 m quadrats positioned at 25 m intervals across depths of 2, 4, 6, 8, and 10 m. A total of 28 species belonging to 24 genera, 14 families, and three orders were identified, with Neogastropoda representing the most species-rich order. Coralliophila violacea had the highest ecological density (5.67 individuals m⁻²) and abundance (approximately 72,000 individuals ha⁻¹), while Conus figulinus had the highest frequency of occurrence (approximately 90%). Community indices indicated moderate species diversity (H′ = 2.87), high evenness (J′ = 0.86), and low dominance (D = 0.08). Species richness declined from 22 species at 2 m to 13 species at 10 m. These findings show that gastropod composition and distribution varied along the sampled depth gradient, with shallower habitats supporting greater species richness. The study provides baseline information for monitoring gastropod assemblages and supporting the management of shallow subtidal habitats in Hutumuri waters.