Beche-de-mer No 31 (January 2011)

New information about sea cucumber biodiversity, ecology and aquaculture is featured in this issue. Reports on research and projects come from various countries, including Fiji, Iran, Oman, Sri Lanka, Madagascar, Philippines and Indonesia. We also present some insights about Mediterranean sea cucumber phylogeny, and a summary of all known saponins.

The first paper is by Cathy Hair et al., who present results from an ACIAR-funded sandfish culture and sea ranching mini-project in Fiji. The main aims of the project were to transfer sandfish hatchery technology to local government and private hatcheries, increase juvenile production, and conduct sea ranching trials with a local coastal community.

Hamilton and Lokani studied sea cucumber populations in the Autonomous Region of Bougainville. They compared results of surveys made in the same areas in 1992 and 2008, which show that the abundance of eight species of sea cucumbers dramatically declined over this 16-year period.

Tsiresy et al. present their results about the growth of Holothuria scabra in micro-farms in Madagascar. The authors found that the growth and survival rates are different in three surveyed villages, and discuss the reasons for these differences.

Olavides et al. also worked on Holothuria scabra but in Bolinao and Anda in the Philippines. The authors inform us about simultaneous mass spawning in sea ranching sites.

Claereboudt and Al-Rashdi evaluated for the first time, the diversity and abundance of holothuroids along the coast of Oman. One of the most striking results is the large difference in sea cucumber community structure between the Sea of Oman and the Arabian Sea.

Taquet et al. and Dabbagh et al. worked on Holothuria leucospilota. Taquet et al. report here about their observations of a large group of H. leucospilota juveniles in Manado (north Sulawesi, Indonesia). Dabbagh et al. describe how they successfully induced spawning of H. leucospilota individuals in Iran. The authors obtained juveniles after a month of rearing and the survival rate was close to 5%.

The abundance, distribution and some biological aspects of Holothuria edulis on the northwest coast of Sri Lanka is the subject of a paper by Dissanayake and Athukorala. The findings of this study could be used to develop proper management plans for the sustainable exploitation of this resource in the future.

Mezali gives some insights on the phylogeny of Algerian shallow-water sea cucumber species. The most striking result is certainly the fact that Holothuria tubulosa, the most common species and the “best known” species in the Mediterranean Sea, forms a clade with two well-separated populations.

Finally, Caulier et al. reviewed saponin diversity in Holothuriidae. No less than 59 triterpene glycosides are reported in the literature.

We also present at the end of this issue several interesting communications, including a report by Cathy Hair et al. on the use of an algal concentrate as potential substitute for the food usually used for the sandfish culture and a report by Sharon Ng on a recent workshop on the “Feasibility of sea cucumber and abalone farming as an alternative livelihood in Semporna, Sabah”.