Morphometric Relationships and Biomass Components of the Otter Shell (Lutraria sp.) from Sanrobone Waters, South Sulawesi, Indonesia

Abstract

Lutraria sp. is a bivalve species with important ecological and economic value in coastal ecosystems and for coastal communities. Sanrobone Waters, Takalar Regency, South Sulawesi, represents a potential habitat for Lutraria sp. and is utilized by local communities as a clam harvesting area. However, biological information concerning the morphometric characteristics, growth patterns, and biomass relationships of Lutraria sp. in this area remains limited, resulting in insufficient baseline information to support biomass estimation, harvest-size determination, and sustainable resource management. This study aimed to analyze the relationships between morphometric characteristics and biomass components of Lutraria sp. using a non-destructive approach. The study was conducted in Sanrobone Waters, with samples collected from three observation stations using purposive sampling based on differences in microhabitat characteristics. The parameters analyzed included shell length, shell width, shell height, total weight, shell weight, flesh weight, and internal shell volume. Data were analyzed using the Shapiro-Wilk normality test, Pearson correlation analysis at a 95% confidence level, and simple linear regression to develop biomass estimation models. The results demonstrated positive and significant relationships between morphometric characteristics and biomass components of Lutraria sp. Shell weight contributed dominantly to total body weight, while increases in shell dimensions were accompanied by increases in flesh weight and internal shell volume. The morphometric characteristics developed in an integrated and proportional manner, reflecting coordinated growth between protective shell structures and soft tissues. Therefore, shell morphometric characteristics can serve as reliable predictors of biomass through a non-destructive approach and have considerable potential for population stock estimation, growth monitoring, harvest-size assessment, and sustainable management of Lutraria sp. resources.