Seyed Ahmad Reza Hashemi
Academic member of the Chabahar Offshore Fisheries Research Center
Sea cucumbers are echinoderms from the phylum Echinodermata and the class Holothuroidea. Sea cucumbers appeared in the oceans during the evolutionary period 540 million years ago. Sea cucumbers are divided according to the presence or absence of the tubular legs, the radial organs, the mouth shape, the presence or absence of the contracting muscles of the mouth and the respiratory tree. Only a limited number of them are on the world food and trade list. These animals are important components of the food chain in ecosystems and coral communities and play an important role as detritus feeder or suspension feeder. They are responsible for stirring and mixing the sediments and while accelerating the recycling of peat, they allow oxygen to penetrate the sediments. Awareness of the resources of aquatic organisms in any water source is the most basic information needed to manage fisheries stocks. This awareness can only be achieved by collecting data on capture fisheries, fishing effort and biomass. Considering the capacity of the Sistan and Baluchestan province in terms of having sea cucumber resources and lesser - known resources in the coastal waters, knowledge of the amount of resources and sustainable harvesting is of particular importance. The Oman Sea, with its unique ecological conditions, hosts a wide variety of aquatic species that have affected the livelihood, employment and economic activities of coastal residents. Therefore, with proper planning, control and monitoring of aquatic resources, sea cucumber can be exploited as the hub of fishery products in the long run and employment can be created through the exploitation of natural resources and the export of products.
Sea cucumber species in Asia and the province
Sea cucumbers in Asia are mainly from the order Aspidochirotida and two families Holothuriidae and Stichopodidae. Out of 125 Sea cucumber species in Asia, 52 species have economic value and their famous genus is Holothuria, Actinopyga, Bohadschia. The Philippines and the Seychelles are important regions for sea cucumber species, and dried sea cucumbers, known as bêche - de - meror trepan, are sold to other Asian countries. About 30 species of sea cucumbers with different economic values are currently being exploited in the Indian Ocean. Sea cucumber resources are fully exploited or overexploited by 12 of the 30 countries bordering Indian Ocean. Overall, about a third of the world's dried cucumber production comes from the Indian Ocean. In 2005, the total catch of sea cucumber was 851 tons (wet weight), valued at $ 112 million. The species of sea cucumber which is dominant in about 80 % of the coasts of Sistan and Baluchestan province is Holothuria leucospilota, commonly known as the black sea cucumber. In terms of economic value, this species is considered as a species with low economic value. This species is widely distributed in sandy and gravel beds, depths of zero to ten meters. The black sea cucumber is deposit feeder and usually prefers nutrient - rich soft substrates. This species has two spawning peaks, winter with strong peak and spring with weak peak, and maturity weight is 180 grams. In a study conducted by Mr. Amin Rad in 2006 and 2018 in Chabahar Bay, four species of sea cucumber were identified as follows:
1.Holothuria leucospilota
2.Holothuria edulis
3.Holothuria hilla
4.Stichopus herrmanni
In addition, based on the distribution pattern, the numerical density of sea cucumber in the eastern regions of Chabahar Bay (Pasabandar - Lipar) is estimated to be higher than that of the western regions of Chabahar Bay (Iran Bandar - Tang). Also, it was reported that the predominant species of sea cucumber were Holothuria leucospilota (79 %) from the family Holothuriidae and Stichopus variegatus (6 %) from the family Stichoputidae. Investigating the status of sea cucumber resources in the province, breeding and rearing of sea cucumber and reviewing different methods of processing sea cucumbers are among the plans for the future research programs of the Chabahar Offshore Fisheries Research Center.