The Ecological Role of Seagrass Ecosystems in Structuring Fish Communities: Species Composition, Feeding Ecology, and Activity Patterns in Tropical Coastal Waters

Abstract

Seagrass ecosystems play a vital role in supporting coastal biodiversity and ecological processes, particularly as habitats for fish communities. This study aims to analyze the ecological role of seagrass ecosystems in the coastal waters of Rutong by examining physicochemical parameters, fish species composition and abundance, stomach content composition, activity patterns, and seagrass density. A qualitative descriptive approach with a field-based ecological survey was employed. Data were collected through field observations, fish sampling, stomach content analysis, and environmental measure­ments, and analyzed using descriptive and thematic techniques. The results showed that water temperature (28 °C), pH (7.74), and salinity (33.3‰) were within optimal ranges for tropical marine ecosystems. A total of 23 fish species with 156 individuals were recorded, with the highest diversity and abundance found in Station 2, indicating the influence of habitat complexity and resource availability. Stomach content analysis revealed diverse feeding strategies, including herbivorous, omnivorous, and carnivorous behaviors, reflecting a well-structured trophic system. Feeding activity was dominant, confirming the role of seagrass as a primary feeding ground, while also functioning as shelter and nursery habitat. Variations in seagrass density across stations further influenced fish distribution and ecological interactions. This study highlights the importance of seagrass ecosystems in maintaining biodiversity and ecological balance in coastal waters and provides valuable insights for conservation and sustainable coastal resource management.