Australia’s Great Barrier Reef is the largest
structure on earth made by living creatures
and the world’s most extensive coral-reef
ecosystem.
But rising sea temperatures, acidification
and agricultural and industrial run-off are
threatening its survival.
In 2015 UNESCO will decide whether to add
the Great Barrier Reef to the World heritage
Danger list.
The reef is in fact a mosaic of thousands
of individual reefs that began forming about
half a million years ago, when a coastal plain
flooded.
The contours of today’s reef follow those
of ancient valleys and hills.
Tiny coral polyps are the basic building block
of the reef.
The colonies they live in create coral forests
that support some of the reef’s diverse
marine life.
One thousand five hundred species of fish,
30 species of whales, dolphins and porpoises
and about 4000 types of mollusc have been
recorded in the reef's waters.
Some, like dugongs and the large green turtle,
are facing extinction.
In 1981 almost the entire reef was declared
a world heritage site.
UNESCO cited the reef’s superlative natural
beauty and the global importance of the reefs
ecosystem as two reasons for its decision.
But the reef’s coral has been disappearing
at a rate of about 0.5% a year.
Marine scientists point to predators, pollution
and climate change as reasons for this decline.
Another threat now looms from coal.
Australia’s government has approved the
dumping of dredging spoil inside the reef’s
waters.
It also plans to increase coal shipments from
the coast adjacent to the reef.
UNESCO has given Australia until February
to come up with an updated conservation report.
It will decide whether the reef will be added
to the Danger List in June.
