Blue coral - Heliopora coerulea - More information
Facts
Kingdom:Animalia
Phylum: Cnidaria (Coelenterata)
Class: Anthozoa
Order: Coenothecalia (Helioporacea)
Family: Helioporaceae
Genus: Heliopora
Species: coerulea (1,7)
Size
Individual polyps less than 1mm diameter. Colonies may reach several metres in diameter (3).
Status
Listed in Appendix II of the Convention on International
Trade in Endangered Species (CITES). International trade in live or dead specimens
is regulated and subject to licencing (5). Trade without
such permits is likely to constitute a criminal offence. In addition to CITES
requirements, regions and countries may have legislation banning or limiting
the collection or trade of blue coral (6).
Description
Colonies can be tree-like, plate-like or column-like (2, 4, 7). The skeleton is dense and blue in colour (2). Living colonies are brown, or greenish-grey (2,3) with minute (9) transparent polyps (7). Blue coral has a calcified skeleton but does not belong to the order Scleractinia.
Range
This species is found in the Indo-Pacific region (1).
Habitat
Blue coral is a common species that can be dominant in the shallower parts of tropical reefs (4, 7, 10). It is common on reef flats, from where it can be easily collected (3).
Biology
The blue skeleton of Heliopora coerulea is caused by the deposition of iron salts in the calcium carbonate skeleton (4). Blue coral is an important hermatypic (reef-building) coral in some areas (4, 10), with the largest colonies being found in Japan (2). Blue coral colonies in the Indian Ocean can also reach several metres in diameter and may cover large areas (9). Like other reef-building corals, blue coral contains symbiotic algae known as zooxanthellae that provide the coral polyps with nutrients (11). The polyps extend from pores in the skeletons surface and capture plankton and organic particles from the water with their tentacles.
Threats
Blue coral is harvested for the live aquarium trade, and may form part of 'coral rock' (2). The blue skeleton is also popular in the marine curio trade and is made into jewellery and ornaments (8). Blue coral, like other coral species, may be threatened by pollution, destructive fishing practices, unsustainable tourism and global climate change (10).
Conservation
Listed in the Convention on International Trade in Endangered Species (CITES), therefore trade in this species is regulated (5). A valid CITES export permit from the country of origin is required to bring blue coral or objects made from blue coral, such as jewellery, into the 158 countries that have ratified the CITES Convention. Blue corals may form part of the marine community in Marine Protected Areas or areas where management plans are in place to protect the coral community.
Further Information
Veron, J.E.N. (2000) Corals of the world, Volume 3. Australian Institute of Marine Science, Townsville, Australia. ISBN: 0-642-32238-
Authentication
Information authenticated by C. R. C. Sheppard
Glossary
Bleaching: some
corals have algae living within their tissues. Bleaching is the full or partial
expulsion of these algae usually in response to stressful environmental conditions,
such as abnormally high temperatures or pollution. Bleaching is often fatal
to the coral.
Colony, colonies (pl.): (relating to corals) Organisms,
such as corals, which are composed of numerous genetically identical modules
(also referred to as zooids, polyps or 'individuals'),
which are produced by budding and remain physiologically connected.
Coral rock: products used in the aquarium trade coral
rock is consolidated material, greater than 3 cm in diameter, formed of fragments
of dead coral and which may also contain cemented sand, coralline algae and
other sedimentary rocks. 'Live rock' describes pieces of coral rock to which
are attached live specimens of invertebrate species and coralline algae.
Hermatypic: reef-building corals.
Hermatypic corals have a close association with algae known as zooxanthellae,
which live in their tissues. These corals are restricted to shallow, tropical,
marine environments. Over time the accumulated deposition of calcium carbonate
(limestone) by many hermatypic corals can form large limestone structures
known as coral reefs.
Marine Protected Area: any marine area,
including its overlying water and associated flora, fauna, historical and
cultural features protected by law or other effective means.
Plankton, planktonic: aquatic organisms that drift
with water movements; may be either phytoplankton (plants), or zooplankton
(animals).
Polyp Polyps (pl.): typically sedentary soft-bodied component
of Cnidaria (corals, sea pens etc), which comprise of a trunk that is fixed
at the base; the mouth is placed at the opposite end of the trunk, and is
surrounded by tentacles.
Reef flats: the top of a coral reef, usually no deeper
than 1-2 metres, where coral growth is stopped by the surface of the water.
Sideways development of the reef may allow reef flats to reach several hundred
metres in width.
Scleractinia, scleractinian: corals
of the Order Scleractinia.
Symbiotic relationship: relationship
in which two organisms form a close association, the term is now usually used
only for associations that benefit both organisms (a mutualism).
Zooxanthellae: Some species of
dinoflagellate algae (a type of single-celled organism which produce their
own food by photosynthesis, using the Sun's energy), which have a symbiotic
relationship (a close association in which both organisms benefit), with some
coral species.
References
1) UNEP-World Conservation Monitoring Centre: Integrated species information Heliopora coerulea. (April 2002). http://www.unep-wcmc.org
2) Bruckner, A., (1998). Guide to Indo-Pacific Corals in International Trade. Available online. (April 2002). http://www.nmfs.noaa.gov/prot_res/PR/coralidmanualfront.html
3) Sheppard, C. R. C (2002). Personal Communication
4) Wood, E. M., (1983). Reef corals of the world: biology and field guide, T.F.H. Publications, New Jersey, USA. ISBN: 0-876668-09-0
5) Convention on International Trade
in Endangered Species (CITES). (April 2002).
http://www.cites.org
6) Wells, S., & Wood E.M., (1991). The Marine Curio Trade. Conservation guidelines and Legislation. Marine Conservation Society, Ross-on-Wye, UK.
7) Veron, J.E.N. (2000) Corals of the world, Volume 3. Australian Institute of Marine Science, Townsville, Australia. ISBN: 0-642-32238-4
8) Oliver, J.K. (1986) Stony corals: Classes Hydrozoa and Anthozoa, In: CITES Identification manual, Gland, Switzerland.
9) Sheppard, C. R. C. (2002) Corals of the Indian Ocean. Sida. CD ROM.
10) Spalding, M.D., Raviolus, C., & Green, E. P. (2001) World atlas of coral reefs. Prepared at the UNEP World Conservation Monitoring Centre. University of California Press, Berkley, USA. ISBN: 0-520-23255-0
11) Barnes, R.S. K., & Hughes, R.
N. (1999). An introduction to marine ecology. Blackwell Science Ltd.
Oxford. UK.