Assessment of the lobster puerulus (Panulirus homarus and Panulirus ornatus, Decapoda: Palinuridae) resource of Indonesia and its potential for sustainable harvest for aquaculture

Abstract

Indonesia has a unique opportunity to establish the world's largest lobster aquaculture industry, based on a significant natural resource of settling puerulus. These seed lobsters can be captured and on-grown to generate high value, consumption size lobsters. However, existing fisheries regulation prohibits fishing of these seed lobsters in Indonesia. Nevertheless, seed fishing occurs widely, and the seed are smuggled into Vietnam, where the Vietnamese gain most of the commercial benefit. By removing access to pueruli and grow-out opportunities, these regulations have diminished the capacity of Indonesian lobster farmers to develop a sustainable grow-out industry. Although the new policies were introduced as a management intervention to protect adult lobster stocks, they have had the unintended consequence of preventing development of lobster aquaculture while having no known benefit on abundance of adult lobsters. This study collected data on the puerulus available in Indonesia, species composition, seasonality, and capture methods.A census of seed capture determined that 5,243,887 pueruli were fished from two bays in the southeast of Lombok in 2014, representing 64,787 pueruli per km2. Surveys beyond Lombok determined there was high abundance of seed in areas with similar environmental characteristics, where local communities had also engaged in seed fishing. The locations identified as having substantial puerulus abundance comprised the southern coast of Java, Bali, Lombok and Sumbawa covering a distance of 1500 km. Puerulus abundance is highest in enclosed bays with distinct currents, relatively high turbidity attributable to terrestrial inflows, and muddy/sandy substrates. Satellite imaging identified all such suitable locations for puerulus settlement, enabling an estimate of total puerulus catch of 103,480,283 per year. The composition of puerulus fished consisted of two species, Panulirus homarus and P. ornatus. P. homarus was most abundant representing between 63 and 87%, while P. ornatus represented 37 to 13%. Seasonality of catch was unclear, with low catch between December and March and higher catches from April to November. The magnitude of the estimated puerulus resource of Indonesia is >20 times greater than that of Vietnam. If used for aquaculture, the seed available can support an industry generating >12,500 t of market size lobster, and provide social and economic benefit to many thousands of households. To achieve this, fisheries policies could be revised and a regulatory framework established to manage the puerulus fishery and support lobster farming. Tropical marine rock lobster aquaculture is a major opportunity for high-value aquaculture production for the Indonesian economy.