Problems related to the farming of Holothuria scabra (Jaeger, 1833)
Lavitra, T.; Rasolofonirina, R.; Jangoux, M.; Eeckhaut, I. (2009). Problems related to the farming of Holothuria scabra (Jaeger, 1833). SPC Beche-de-mer Information Bulletin 29: 20-30
In: SPC Beche-de-mer Information Bulletin. Secretariat of the Pacific Community: Noumea. ISSN 1095-4943, meer
| |
Auteurs | | Top |
- Lavitra, T., meer
- Rasolofonirina, R.
- Jangoux, M., meer
- Eeckhaut, I., meer
|
|
|
Abstract |
Different problems related to Holothuria scabra farming were observed at the sea cucumber aquaculture project Madagascar Holothurie S.A. (Toliara, Madagascar). In this paper, those problems are presented, their impact on sea cucumber production is characterised and solutions permitting to avoid or to minimize their impact are proposed. A drastic salinity drop occurred during low tides in one period of the year and after cyclones. This provoked behaviour troubles in the H. scabra: individuals stayed burrowed in sediment even at night, a period when they are usually at the surface. However, that did not affect their growth. When possible, we suggest choosing a site far from areas where salinity is apt to drop.Isopods Cymodoce sp. infested sea cucumbers in outdoor ponds during the hot season, provoking a high mortality rate (average 8% week-1) in cultivated H. scabra. The introduction of the carnivorous fish Terapon jarbua in the ponds proved successful in preventing this problem. The fish eat isopods and can eliminate them within 10 days. Infections induced by isopods totally disappeared within two weeks.The crabs Thalamita crenata were abnormally abundant in the pens during some periods of the year. They are the most redoubtable sea cucumber predators in the region and may provoke the mortality of the entire stock within one month. The crabs attack principally the newly transferred juveniles. The adults whose weight was more than 250 g were never affected. The elimination of the crabs in the surrounding area is to be carried out before the transfer of the juveniles and a daily watch of the pens is necessary in order to limit the impact of predation on production. |
|