Fish Otolith Analysis in Southeast Asia: Expanding its Taxonomic Roots to More Ecological Targets

Otoliths, crucial tools for understanding fish biology and ecology, offer valuable insights into fisheries science in Southeast Asia. Traditionally used for age identification through shape analysis and growth ring counting, otolith studies have evolved to encompass broader ecological investigations. This review synthesizes literature on fish otoliths in Southeast Asia to identify research gaps and suggest future directions. Utilizing targeted keywords, we mined data from scientific search engines, focusing on peer-reviewed articles. Our analysis spans 1988 to 2021 and collated 129 publications, which were trimmed to 91 reviewed scientific articles. Otolith microstructure emerged as a primary research area of interest, with a focus on catadromous fishes from the Anguillidae family. Geographically, publications are concentrated in marine fish populations across archipelagic nations such as Indonesia, the Philippines, Malaysia, and the Vietnam Peninsula. Practical gaps, including validation precautions and cost-benefit analyses, potentially underscore the importance of methodological rigor and innovation in otolith research, but advances in mass-based age determination techniques and radiometric analysis present promising avenues for addressing these challenges. As global otolith research expands beyond aging studies, we urge fisheries scientists to explore innovative research areas outlined here to enhance their expertise in otolith microstructure and morphometric techniques. By integrating innovative approaches and multiple validation methods, researchers can enhance the reliability and accuracy of otolith-based age determination, ultimately advancing our understanding of fish population dynamics and supporting sustainable fisheries management practices in the Southeast Asian region.