Short communication – The first inventory of the nest placement of horseshoe crab (Tachypleus gigas) in Indonesia

Abstract

Previous studies have reported that extant horseshoe crabs, including Atlantic and Asian horseshoe crab, spawned in intertidal zone during high tide season. Limited information about spawning nest of the horseshoe crab especially Tachypleus gigas in Indonesia has not been known yet. Moreover, according to the IUCN, the conservation status of T. gigas is still data deficient. During the fieldwork, we found the location that indicated as the spawning ground or nest placement of T. gigas. This is the first time when the spawning area of horseshoe crab is found in Subang, Indonesia. There were three clutches of eggs and the total number was 375-534 eggs in varying depth (5-20 cm) below the sand. The second observation in the same location on January 16, 2020, found a pair of T. gigas laying their eggs and the number was 244 eggs in varying depth (5-15 cm). The characteristics of nest placement of T. gigas that found in Subang was located on the small island in the middle of the sea. The island is an uninhabited island that has mangrove area and sandy substrate. Thus, based on what was found Burung island indicated as the spawning ground of coastal horseshoe crab (T. gigas).