bread sea cucumber
This large loaf-shaped sea cucumber is often seen in the seagrass
meadows of our Northern and Southern shores. While small ones usually
remain buried in the sand, larger ones might be found above the ground.
Younger sea cucumbers are usually found nearer the shore. As they
grow bigger, they move into deeper waters to breed.
Features: 15-20cm long. Rather
flat square-ended loaf-shaped body with a distinct upper and underside.
The upperside is darker and often has little folds and sometimes,
black bars; thus shore guides often jokingly refer to it as the 'Garlic
bread' sea cucumber because that's what it looks like. The underside
is flat and pale or white. There are little tube feet regularly distributed
all over the body.
What does it eat? It feeds on
and gathers detritus with the 20 or so short feeding tentacles that
surround its mouth which usually faces downwards towards the ground.
Pea crabs (Pinnotheres sp.) are sometimes found living in their
rear ends! These cannot be seen unless the animal is killed and dissected,
so please do not prod the sea cucumber to try to see these crabs.
Role in the habitat:
study has found that this sea cucumber plays an important role
in the health of seagrasses. Much like terrestrial earthworms, by
eating sediments and burrowing in the ground, the sea cucumber makes
more nutrients available to the seagrasses. More about this on the
Human uses: This harmless sea
cucumber is among those collected as a Chinese delicacy. They are
gutted and dried for sale as ‘trepang’ or ‘beche-de-mer’. It is called
sandfish in the trade. Growing up to 40cm and weighing up to 1.5kg,
it is considered the most widely collected and among the more valuable
sources of beche-de-mer. Tests indicate these sea cucumbers contain
toxins. They must be properly prepared before they are safe to eat.
Collection of sea cucumbers has been a traditional activity for centuries
by coastal peoples in many parts of the world ranging from Madagascar
to the Philippines. However, the recent high market price of this
delicacy has resulted in increased collection in last 20 years. Some
edible sea cucumbers are globally threatened by over-collection. In
some areas, such sea cucumbers have become scarce. In others, specimens
collected are smaller and have to be harvested from deeper waters.
Efforts to culture these edible sea cucumbers have only just started.
Status and threats: The Garlic
bread sea cucumber is listed as 'Vulnerable' on the Red List of threatened
animals of Singapore. It is threatened by habitat loss due to coastal
development. Overcollection can also have an impact on local populations.
Chek Jawa, Jul 08
Mouth with short feeding tentacles.
bread sea cucumbers on Singapore shores
Cyrene Reef, Apr 08
Tan, Leo W. H. & Ng, Peter K. L., 1988. A
Guide to Seashore Life. The Singapore Science Centre,
Singapore. 160 pp.
the Sea Cucumber by Arjan Heinen: the story of sea cucumber
harvesting in Danao Bay, Philippines and how it affected the lives
of the fisherfolk there.
Information Bulletin on the Secretariat of the Pacific Community
(SPC) website: details of the trade, impact on wild populations,
efforts at hatching larvae and mariculture in various parts of
the world including the Solomon Islands, Madagascar, Lamu Atoll,
Washington State., Mexico, Australia.
Evaluation of the Trade of Sea Cucumbers in the Galapagos Islands
during 1999: detailed information.
cucumber fishery in the Philippines Sabine Schoppe State Polytechnic
College of Palawan, Aquatic Science and Technology Institute:
cucumber ranching about cultivation of Holothuria scabra
on the wild shores of singapore blog.
Ecology of Holothuria scabra! The Cuke-Seagrass Connection!
on the echinoblog.
of Holothuria scabra in seagrass health on the TeamSeagrass