Wild

Tubular Sea Cucumber

Holothuria tubulosa

Common Name(s)

Cotton spinner

High Risk

No data available OR Proven poor fishery status and/or high risk of decline to poor status without appropriate management / ineffective management and/or high environmental impact. If species is listed as vulnerable, endangered or critically endangered then stop sourcing.

French

Holothurie tubuleuse

German

Seegurke, Seewalze

Spanish

Carajo de mar, Cohombro de mar pardo, Cohombro tubo

Greek

Αγγούρι της θάλασσας

Date of Assessments

October 2021

Peer Reviewer

Dr Steven W Purcell, Southern Cross University, Australia

Assessment Organisation

The University of Hong Kong

SEASONAL AVAILABILITY

In Southern Turkey, a closed fishery season annually from June to October for sea cucumbers is in place (González-Wangüemert et al. 2018) and thus sea cucumber collection is prohibited from June to October. Closed season for sea cucumber collection in Algeria is 1 August to 15 September each year. However, Tubular Sea Cucumber is available all-year-round, mainly in dried form, so it is difficult to identify the collecting season.

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Overview

  • Tubular Sea Cucumber (Holothuria tubulosa) is a species distributed in the Mediterranean Sea and the Northeast Atlantic Ocean. This species can be found on various sea bottom types down to 100 m depth, with animal density usually higher when shallower than 10m. It occurs in shallow sublittoral seagrass meadows.
  • This species can grow up to about 38 cm total length, although maximum length varies with location, and matures at about 220 g weight. The species is a broadcast spawner, mature individuals release eggs and sperm and external fertilization is in the water column.
  • Sea cucumbers play an important role in recycling bottom sediment and therefore have a valuable ecosystem function - this is not explicitly managed for.
  • Global wild capture of sea cucumbers (different species combined estimated as live weight) in the latest FAO estimation in 2019 was about 59,000[1] tonnes with about 27,000 tonnes from the Atlantic Ocean and Mediterranean Sea (FAO 2021).
  • Tubular Sea Cucumber is economically valuable, targeted by fishermen together with other species of sea cucumber, especially for exports.
  • The commercial value is mostly determined by the size and the thickness of the body wall, among other criteria. Since the final product is the dry body of the sea cucumber, the profitability would depend on body wall thickness and water content which are different between species.
  • Some animals in the population occur in shallow waters (<40 m depth) making them readily accessible by divers (free or with scuba or hookah equipment), while other animals can occur in deeper waters making them inaccessible to collection by divers. It is not known what proportion of the population is shallow and, hence, readily accessible to collectors.
  • Signs of over-exploitation were detected in main export countries of the species including Turkey, Algeria and Morocco.
  • This species has seen increased demand in Asian markets in recent years, becoming one of the most intensively exploited sea cucumbers from the Mediterranean Sea. Aquaculture (hatchery-based) operations became feasible over the last five years or so.
  • The genus Holothuria includes a number of threatened species (three species were recently added to CITES Appendix II). The life history of the Tubular Sea Cucumber and its high economic value could make it similarly susceptible without management. Hence, a precautionary approach should be taken in the sourcing of this species using the most up-to-date information available. Market price stands out as the key driver of extinction risk in commercially exploited sea cucumbers so elevated market price for the species may signal a problem in the wild population.
  • Cadmium and lead values obtained from muscle tissue of Tubular Sea Cucumber in one region in Turkey exceeded acceptable trace metal values, reflecting deterioration of the substrate in which the species lives; the body flesh of the species reflects the substrate composition. This is of possible human health concern.
  • Some smuggling of the species is known to occur.
[1] The FAO statistics are catalogued on FishStatJ software by FAO and by default (not by specification), the Unit name is “Tonnes – live weight” but major published reviews (e.g., FAO global review report) illustrate that many of the countries are actually reporting dried products, which are very roughly one-tenth of the weight of the fresh live animals. So, a large number of the data entries are underestimating live weight by an order of magnitude. The discrepancies in FAO data have been known for many decades and reported in several publications.

Direct collection by divers (with compressors)

This collection method is highly selective and therefore likely to cause negligible bycatch and to have limited impacts on natural habitats. However, removal of the species, which is important for recycling soft sediments, could have ecosystem impacts.

  • The Latin species name
  • Evidence of the country of origin
  • Evidence of production method (hatchery or wild sourced)
  • Evidence that the species is caught according to national guidelines and regulations for the species (e.g. compliant with minimum sizes, seasonal protections, etc.)

FISHERIES IMPROVEMENT PROJECTS

No Known FIP

COUNTRY SPECIFIC RISK ASSESSMENTS

  • Tubular Sea Cucumber (Holothuria tubulosa) from Turkey can be considered to be a high risk.
  • Tubular Sea Cucumber is highly valuable in Turkey and can be exported at USD 135-145/kg (Günay et al. 2015)
  • Wild stocks of Tubular Sea Cucumber in Turkey are over-exploited, as evidenced by small size of collected individuals and genetic analyses (González-Wangüemert et al. 2018).
  • National regulations on collection of wild Tubular Sea Cucumber differ in Northern and Southern Turkey. In Northern Turkey, only hand collection, optionally with scuba diving equipment, is allowed. In Southern Turkey, a closed fishery season annually from June to October for sea cucumbers is in place (González-Wangüemert et al. 2018).
  • However, illegal fishing and over-exploitation are commonly recorded in the country.
  • Tubular Sea Cucumber (Holothuria tubulosa) from Algeria can be considered to be a high risk.
  • Catch data for the species in Algeria are lacking. However, sea cucumbers are overexploited in shallow depths in some areas and fishermen go further and deeper for collection (Mezali & Slimane-Tamacha 2020).
  • Before development of the sea cucumber trade in Algeria by Chinese communities in the 2000s, sea cucumbers were mostly collected and used as fish baits by the local communities.
  • Wild caught Tubular Sea Cucumber are valuable in Algeria. Fresh ones can be sold at about DZD 200–700/kg (EUR 1.5–5.9/kg), meanwhile dried is worth about DZD 4800–12,000/kg (EUR 36–90/kg) (Mezali & Slimane-Tamacha 2020).
  • National regulations on collection of wild sea cucumbers include prohibition of collection for commercial purpose, limiting collection by gleaning and diving and a yearly 46-day closing period (from 1 August to 15 September).
  • Given the above prohibition of commercial collection and exports, Hong Kong seafood importers should not be importing any tubular sea cucumber into Hong Kong from Algeria.
  • Designated management measures and the seasonal closure for the species are not set based on scientific advice. Illegal, Unreported and Unregulated (IUU) fishing and trade continues. Control over catches is lacking.
  • Tubular Sea Cucumber (Holothuria tubulosa) from Morocco can be considered to be a high risk.
  • Over-exploitation and extensive stock decline was recorded for wild Tubular Sea Cucumber in Morocco in 2014 (de Greef 2018; Neghli & Mezali 2019).
  • The high value of wild Tubular Sea Cucumber makes them targets of local fishermen as one of the big sources of income (de Greef 2018).
  • All exports of sea cucumbers from Morocco are banned since 2014. However, smuggling of sea cucumbers from the country still frequently occurs (de Greef 2018).
  • Given the above, Hong Kong seafood importers should not be importing any tubular sea cucumber into Hong Kong from Morocco.