Preliminary assessment of Tripneustes gratilla populations in Seagrass Beds of the Spermonde Archipelago, South Sulawesi, Indonesia

Abstract

Many sea urchins, including the collector urchin Tripneustes gratilla, are well known for their role as herbivores, contributing to the control of fast growing macroalgae that can potentially overgrow and dominate seagrass beds and reef flats. Tripneustes gratilla is a short-spined sea urchin that can be easily found and collected by hand from the seagrass meadows which are their main habitat, especially during low tide. The exploitation of this species in Indonesia began to expand several years ago when the demand for T. gratilla gonads started to rise, for both commercial purposes and household consumption. This study aimed to determine the population and distribution of T. gratilla in seagrass ecosystems with different conditions across the Spermonde Archipelago, South Sulawesi, Indonesia. The results indicate that T. gratilla population abundance and size distribution are affected by several factors: seagrass condition, water quality, and the intensity of sea urchin collection. The results also emphasize the urgent need for developing and implementing effective management to ensure the sustainability of this important sea urchin species.