Biological reproduction variables of scalloped spiny lobster (Panulirus homarus Linnaeus, 1758) in the west coast of Lampung province

¹ Department of Aquatic Resources Management, Faculty of Fisheries and Marine Sciences, IPB University, Bogor 16680, Indonesia
² Center for Coastal and Marine Resources Study, IPB University, Bogor City 16127, Indonesia
³ Department of Aquaculture, Faculty of Fisheries and Marine Sciences, IPB University, Bogor 16680, Indonesia

^* Corresponding author: zairion@apps.ipb.ac.id

Abstract

The scalloped spiny lobster (Panulirus homarus) is one of the dominant lobster species caught by fishermen in the west coast of Lampung Province. The spiny lobster fishing seems to be high pressure due to the catch result having a reasonable price for domestic and export market. However, little information on the biology of this species in the west coast of Lampung Province is considered for management. This study aimed to analyze the biological reproduction variable of scalloped spiny lobster, i.e., sex ratio, length-weight relationship and relative condition factor, maturity, reproductive potential, and spawning type. The sample was collected by simple random sampling method on the main holding center from October 2021 to March 2022. Results showed that the caught of P. homarus carapace length was in the range of 41-94 mm, the sex ratio was about 1:1.12, there was a negative allometric growth pattern for both sexes, the condition factor, and the gonadosomatic index tended to be increased from October to December, and then decrease. Gonad with fully mature stage (stage III) was found every month for both sexes, and the peak of spawning season occurs in November-December. Fecundity as the reproductive potential of P. homarus was in the range of 762-182,000 eggs, while size at onset maturity or mean size of first spawning was at 63.10 mm carapace length. Spawning patterns tend to be partial spawners. Females of P. homarus below the size at onset maturity are often caught. It is recommended to this fishery that minimum legal size should be applied in the carapace length greater than 64 mm.