Holothurian Dive Harvesting

What are Holothurian or Sea Cucumbers: Holothurian or Sea Cucumbers (Class: Holothuroidea) are cylindrical invertebrate animals that live in seas worldwide. They are found in a variety of sea floor habitats, from warm tropical waters to cold deep sea trenches. These nocturnal animals have a life span of about 5 to 10 years.

Anatomy: The body of a Holothurian or Sea Cucumber is elongated, leathery and muscular; spines are contained within the skin. These echinoderms have no arms but do have five-part symmetry. Surrounding the mouth are 8 to 30 tentacles or modified tube feet. Five double rows of tube feet with tiny suction cups run along the body; they are used for crawling along the sea bed or anchoring to a rock. A Holothurian or Sea Cucumber breathes by pumping sea water in and out of an internal organ called a respiratory tree. They have no brain and range in size from a few centimetres to the giant two metre Tiger's Tail Sea Cucumber (Holothuria thomasi). Some Holothurians or Sea Cucumbers burrow into the sea floor to remaining undetected by their predators.

Diet: Holothurians or Sea cucumbers eat decaying matter that floats in the water or is in the sand.

Predators: Turtles, crustaceans, many fish, and people eat them. Holothurians or Sea cucumbers can expel most of their internal organs to confuse predators - they later re-grows the organs. Some species' bodies contain toxins that can deter attackers.

Beche-De-Mer Trade: The market for beche-de-mer (the food market name for Holothurians or Sea Cucumbers) is dominated by only two trading nations, namely Hong Kong/China and Singapore, although products are imported from all over the world. Imports from South Pacific Island countries consist of high-value species of dried beche-de-mer.

The Asian market for beche-de-mer is estimated to be worth US$ 60 million annually. Seven countries account for almost 90 per cent of the total trade of fresh/frozen/dried beche-de-mer, with an average quantity of 13,000 metric tons.

Almost 95 per cent of the beche-de-mer is imported in dried form. A small volume of fresh/chilled and frozen products is imported into Hong Kong and Taiwan for speciality restaurants.

Their consumption is high during the Chinese New Year, at mid-year and year-end festivals, dinners and at almost every wedding dinner, irrespective of income group.

Harvesting: The major commercially harvested species of Holothurian or Sea Cucumber are:
Sandfish
White teatfish
Deep-water redfish
Blackfish
Elephant’s trunkfish
Prickly redfish (see picture to left)

Holothurian or Sea Cucumbers are harvested mainly by divers breathing surface-supplied air from hookah equipment, by free-diving from dinghies or by hand collection along reefs at low tide.

Once collected, the animal is gutted, graded, cleaned, boiled and dried. In this processed form the product is usually referred to as beche-de-mer.

Currently there are three operators collecting beche-de-mer in Queensland, Australia and entry to the fishery is restricted. Management strategies that limit the harvest of beche-de-mer include:

• Catch limits - There is a Total Allowable Catch (TAC) of 380 tonnes for the beche-de-mer fishery. A TAC is a limit or quota set on the weight or number of a certain species that can be taken each season, based on the yield the population can sustain.
  
   
• Quotas - Operators are allocated an individual transferable quota that they can catch at any time in the season. Once they have caught their quota they have to stop fishing, but the other fishers can keep fishing until they have used their quota. Each fisher can thus decide when they want to catch their quota to get the best economic return.

Divers harvesting the beche-de-mer, with one of the Queensland registered companies are usually paid by item collected. This involves a long stint out in the Great Barrier Reef, Coral Sea or the waters off the coast of Papa New Guinea.  The vessels have quite cramped sleeping conditions as most of the internal part of the ship is reserved for the catch. But the trips I have worked on always had an excellent cook to keep us fed with a huge variety of food which had either been brought along in the the freezer holds and or caught during the night before. Trips are approx 2-4 weeks long and experienced divers can expect to earn close to A$2,000.00 per week.  This sounds an attractive wage but it is extremely hard work and consists of about 5 dives a day, to about 30-35m. The first dive is usually about 5am and the last is done before it is too dark to work at depth. 

All dives are performed on Western Australian Dive Harvesting Tables which are a commercial decompression dive table system. Divers will be dropped down to the required depth with the aid of a weighted line and once they reach a certain set bottom time, they start there assent ending up at approx 9m performing a set safety stop on an additional surface supplied hose pumping medical grade pure oxygen. The safety stops are always done in pairs to allow the partnering diver to monitor his colleague for signs of oxygen toxicity and keep check on their depth etc.

The diving guidelines have to be followed strictly and any attempt to not follow the safety rules can and does lead to accidents such as these:

CAIRNS, Australia (15 July 2004): A diving company has pleaded guilty in the Cairns Magistrates Court to breaches of Workplace Health and Safety regulations resulting in grievous bodily harm.
Two incidents occurred on Kelso reef off Townsville in late 2002, involving The Holothurian Diving company which is involved in the beche-de-mer trade.

In the first incident, diver Geoff Woodhead surfaced after eight minutes of decompression despite dive computer advice to stage for 48 minutes. He intended to return to decompression depth with a bottle of pure oxygen to speed the process but became distracted and did not return to the water. He then collapsed on the boat's deck with decompression sickness.

In the second incident, backpacker diver Lars Bang from Sweden was struck by the propeller of a 40 horse power outboard motor. He suffered severe lacerations when struck by the dory which was being driven by a driver under instruction.

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