Shellfish Breeding and Hatchery Management (2+1)

22.1.1 Introduction to Holothurian seed production

Holothurians are wonderful natural resources in India and they are found aggregated in selected maritime states and Tamilnadu is one among them. Sandy shores together with conducive climate for their breeding make them habituate in the particular location restricting its distribution.
Hornell (1917) reported that the beche-de-mer industry in India was an ancient one probably introduced by the Chinese (might be about 1000 years ago). Since sea cucumbers fall easy prey and easily captured, their population is over exploited in many parts of the world. (Example, beche-de-mer industry in the Maldives, which developed in 1985 with a modest export of 31 kg, now the resource was in danger of over exploitation (Joseph and Shakeel, 1991; Joseph, 1992). James and James (1994)wrote on the needs for conservation and management of sea cucumbers in India.
A new resource of sea cucumber, Actinopyga echinites, was exported for the first time from India in 1989 and by 1992 this resource had become scarce (James and Badrudeen, 1995). Another species, A. miliaris, was collected for the first time in 1992 and, within 2 months, more than 0.6 million specimens were caught.

James and James (1994) published a handbook on Indian sea cucumbers to facilitate identification of commercially important sea cucumbers from India. James and Ruparani (1999) gave an account of new resources of beche-de-mer and the management of these resources in India. In order to replenish the natural populations, hatchery technology for juvenile production and sea ranching was developed by the Central Marine Fisheries Research Institute in India.

James et al. (1988) produced juveniles of H. scabra for the first time in 1988 at Tuticorin in India. Following this same technology, juveniles of this species have been produced in Australia, Indonesia, New Caledonia, Maldives, Solomon Islands and Viet Nam in recent years.

The fertilized eggs develop into larvae which may be planktonic for 65 -70 before settling on the bottom and changing into juvenile sea cucumbers. Juveniles are very secretive and hide among sea weed, under stones, and in crevices. Growth is slow, requiring at least four to five years to attain adult size of 500g bw. Their life span may be more than eight years.