Development of the red rock lobster, Jasus edwardsii, from egg to juvenile

Abstract

Mature red rock lobster, Jasus edwardsii were air freighted from the North Island, New Zealand to Japan in 1985. During most years since, egg extrusion has taken place during November and December and egg hatching from February to April. In the main experiment, phyllosomas were cultured in 100‐litre containers. Each container had an upwelling system, connected either to a Nanno‐chloropsis culture tank (Experiment 1) or to a coral sand filter tank (Experiment 2). Artemia nauplii and mussel gonad were the main foods provided. The numbers of 1st, 5th, and 15th instars were 12 000, 1500, and 137 respectively in Experiment 1, and 1500, 99, and 67 in Experiment 2. The intervals between Instars 1–4 and 4–14 were 43 and 175 days respectively for Experiment 1, and 43 and 169 days for Experiment 2. In Experiment 1, nine phyllosomas (13–15th instar) died during metamorphosis to the puerulus and a single 17th instar metamorphosed 303 days after hatching, 19 days later moulting into the juvenile. In Experiment 2, six 17th instar larvae metamorphosed 293 days and more after hatching, with all dying over the following 3 days. In an ancillary experiment, 30 phyllosomas were cultured in each of two 30‐litre tanks containing microalgae: survival was higher, 20% and 43% reaching Instars 14/15 and six metamorphosing after 212–274 days. In all experiments, the developmental sequence was generally consistent with that for larvae from the field. Gill buds appeared at the 13th instar and gills were complete at the 17th instar. Improved culture methods are required to reduce late‐stage mortalities.