wild places | wild happenings | wild news
make a difference for our wild places

home | links | search the site
  all articles latest | past | articles by topics | search wildnews
wild news on wildsingapore
  The Australian 15 Nov 06
Australian Keppel Island coral reefs 'completely' dead

HARD coral on a large network of shallow reefs near Keppel Island have been completely killed off, Central Queensland University researchers confirmed yesterday.

Marine biologist Alison Jones said that instead of monitoring this year's coral spawning event she had witnessed widespread coral bleaching.

"(It) resulted in 100 per cent mortality of all hard coral species on the reef flats at Middle, Shelving, Monkey, Miall and Halfway reefs," she said. "Even anemones were bleached white.

"We think that this may have been caused by a coincidental heavy downpour and extreme low tide just after midnight on Friday, November 3.

"Following a summer bleaching in January and February, this is devastating for the Keppel region particularly because of the timing just before what would have been the mass spawning event," she said.

"The deeper corals were untouched and sections of reef that had good current movement survived because the fresh water would have been quickly mixed with seawater."

CQU chemical and biomedical sciences chief Graeme Pegg described the downpour preceded by last summer's coral bleaching as "a double whammy".

"It's a fairly calamitous event. These reefs copped a fair hiding. They are definitely compromised," he said.

Dr Pegg, with molecular geneticists Billy Sinclair and Bill Astden, have just received funding to find out how reef bleachings affect the biodiversity of fish species.

Ms Jones said: "In light of the considerable threat of climate change causing annual bleaching events within the next 30 to 50 years, (according to 1999 studies by Hoegh-Guldberg), this study could influence DPI fisheries regulations, marine park management and may lead to the instigation of a Special Management area for the Keppel region."

Dr Pegg and his colleagues are finishing a three-year study that found the "one-size-fits-all" marine protection measures, designed to protect breeding fish from commercial and recreational fishing, do not work for all species.

Newly hatched baby fish do not rely on sea currents to take them to safe places to grow. After spawning, perhaps up to 60 per cent of tiny fish larvae, as small as 3-4mm long, will swim against the current as they actively try to return to their home reef. "They are smelling and hearing the reef," Dr Pegg said.

Studies have shown fishing closures do protect spawnings of sweetlip but not necessarily red emperor, coral trout, cod and other important species because they spawn at times outside of the fishing closure periods.

"Will fish biodiversity be affected in a major way by bleaching, or will we see the recruitment of larvae from adjacent reefs that have not been bleached? Reefs do regenerate but it will be interesting to see how quickly," he said.
links
Related articles on Wild shores
about the site | email ria
  News articles are reproduced for non-profit educational purposes.
 

website©ria tan 2003 www.wildsingapore.com