Actualité scientifique
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N° 474
February 2015
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A new future for corals
Coral reef structure in French Polynesia, dominated by the genus Porites (© IRD / S. Andréfouët).
Coral reefs, true reservoirs of biodiversity, are seriously threatened by human
activities and climate change. Consequently, their extinction has often been
heralded. Now, researchers are painting a less gloomy picture: the planet’s reefs
are not doomed to disappear. But they will be very different from the ones we
presently know. A new coral fauna will emerge, coming from the species that are
most resistant to temperature increases.
Did you know?
Coral ecosystems are among the richest in species and the most productive on the planet. They provide a habitat
for more than a quarter of marine animal and plant species.
In addition to their ecological value, coral reefs have an economic importance: almost 500 million people, mainly in
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CONTACTS
Some reefs are recovering
Are coral reefs condemned to disappear?
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phenomenon of coral bleaching due to
ocean warming, outbreaks of a coral-eating
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fear. But today, scientists are revising their
pessimistic forecasts from the previous
decade. In fact, recent research works
show that, while numerous coral species
have indeed been declining for more than
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increasing in abundance. Consequently,
some reefs have recently managed to
recover.
Consequently, the underwater landscapes
of the future will be very different to the
ones that have been known for millennia.
However, much remains to be discovered
regarding this new coral fauna and its
features. One question in particular remains:
will these new eco-systems continue to
meet the needs of the populations who
depend on them?
Expanding coral genera
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years, IRD researchers and their partners
observed the ecological development of
seven coral reefs throughout the world:
two in the Caribbean, in Belize and in the
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Hawaii, Moorea and the Great Barrier Reef
in Australia. Consequently, the scientists
have shown the increase of certain genera,
like the Porites reef corals, real reef builders
that can resist temperature rises well.
They have also put these recent changes
into perspective with regard to past
events recorded in fossil reefs, showing
that the abundance and structure of coral
populations have already varied greatly
over the course of past millennia.
California State, California, Davis and California,
Gaëlle COURCOUX
Information and Culture
Department
T. +33 (0)4 91 99 94 90
03"#%23!';+(.5/(
Partners
French Research Institute for Development, Labex
www.ird.fr/la-mediatheque
CORAIL - CRIOBE in Moorea, universities of
Santa Barbara, Pennsylvania, Iowa, North Carolina,
Miami, Florida and the Virgin Islands in the United
States and Western Australia, Hawaii Institute of
Marine Biology, National Center for Ecological
Analysis and Synthesis, Florida Institute of
Technology and Wildlife Conservation Society in the
United States, National Museum of Marine Biology
and Aquarium in Taiwan, Australian Institute of
Media Contact
Cristelle DUOS
Marine Science and The Cawthron Institute in New
Zealand.
T. +33 (0)4 91 99 94 87
References
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EDMUNDS P. J., ADJEROUD MEHDI, BASKETT M. L., BAUMS
I. B., BUDD A. F., CARPENTER R. C., FABINA N. S., FAN
T. Y., FRANKLIN E. C., GROSS K., HAN X. Y., JACOBSON
L., KLAUS J. S., MCCLANAHAN T. R., O’LEARY J. K., VAN
OPPEN M. J. H., POCHON X., PUTNAM H. M., SMITH T.
B., STAT M., SWEATMAN H., VAN WOESIK R., GATES R. D.
Persistence and change in community composition
Indigo, IRD Photo Library
Daina RECHNER
of reef corals through present, past, and future
climates. Plos One, 2014, 9 (10), p. e107525. ISSN
T. +33 (0)4 91 99 94 81
1932-6203
+).+1&;+(.5/(
Contacts
Mehdi Adjeroud, IRD researcher
*#".+52.I#(&'.;+(.5/(
T. : 06 95 54 04 95
Photos : www.indigo.ird.fr
UMR !"#$%&'() *'"%+,) ,&#(#-.) #/) 01,) 2'&%3&) '+4)
5+4%'+)#&,'+6)7)89!:;258 (IRD / CNRS / University
of La Réunion)
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Towards new underwater landscapes
These new data have enabled them to
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to revise their forecasts for the coming
decades. As ocean temperatures continue
to rise, a subset of “winning” species will
thrive: those that have the greatest heat
tolerance, the best population growth rates
or the greatest longevity. These species
should progressively populate the planet’s
reefs, until they dominate them entirely.
Coordination