L'élevage du Loup tropical (Lates calcarifer, Bloch) en Polynésie Française. Techniques d'élevage - Synthèse de neuf années de recherche

Lates calcarifer, a species originated from Southeast Asia and Australia. Was selected among several tropical finfish species because its particular ability for aquaculture. Nine years of research led to a rearing technology adapted to the environmental and socio-economical conditions of French Polynesia. This report is a synthesis of the works that resulted in the control of the whole rearing cycle. A captive broodstock was necessary when using such an introduced species. This fish, a protandrous hermaphrodite, presents a spawning seasonality. A broodstock conditionning facility was designed to get mature spawners throughout the year. Environmental manipulations associated with a hormonal induction method guaranteed egg production aIl over the year. Various larval rearing methods were tested. A viral pathology affected numerous trials of intensive larval rearing. Consequently a semi-intensive method was developed to produce 20 to 25-day-old larvae ready for weaning. Preliminary trials of extensive larval rearing (Australian method) were conducted in fertilized earthen ponds. This method provided encouraging results and could favor the development of this activity in French Polynesia. Setting up the feeding scheme. food and grading frequency for the weaning and nursery phases were necessary to settle the 3 g-juvenile production technology. Such juveniles were ready for stocking in net-cages. The two-step growing-out up to the plate-size (350 g) were carried out in floating net-cages in the lagoon for 7 months. A specifie artificial pelleted food was formulated at the COP and manufactured by a commercial factory.