Barrier Reef
http://www.abc.net.au/news/newsitems/200601/s1559317.htm
Scientists hold grave fears for Great Barrier Reef
By Lisa Millar for PM
Australia's hot summer has had a devastating effect on the Great Barrier Reef.
Coral reef specialists, just back from diving around the Keppel Islands, are comparing the severity of the damage to the worst case ever recorded in 2002.
The University of Queensland scientists say they were shocked by the underwater scene that greeted them and are concerned the entire reef may be at risk of destruction from global warming.
Professor Ove Hoegh-Guldberg said most of the reefs the team saw are now completely bleached.
"Going down to 10 metres, every pieces of coral was a glowing white colour - all that brown colour had disappeared and that was surprising for us," he said.
He said it was especially alarming now because it looked as bad as when he dived the reef in 2002, but that was in April after several more months of summer heat.
Professor Hoegh-Guldberg whose work on coral reefs is internationally respected is praying for two months of cyclonic stormy weather to stir up colder deeper water - the only thing that will save the coral.
"But of course asking for two months of stormy weather is a big ask and if we get a couple of weeks of sunny weather we're going to have a problem," he said.
The professor chairs a group that is part of the largest international network of coral reef scientists in the world, funded by the World Bank, and the group is now on high alert.
And the fact that normally reserved scientists are issuing such alarming statements has the Australian Conservation Foundation's Don Henry worried.
"The important thing from this warning is that we're starting to see this damage to the reef from warmer waters and climate change happen more often and more extensive," he said.
"There's going to be a point when the reef just doesn't recover."
With February, the hottest month, just ahead, this is a critical time.
The last severe cases of bleaching occurred in 1998 and 2002, the last leaving more than 5 per cent of the reef destroyed.
Professor Hoegh-Guldberg is convinced global warming is to blame.
"No one with any credibility in this field is doubting that we're seeing the first signs of a major change in an ecosystem due to climate change," he said.
"It simply underscores the absolutely critical importance of getting global greenhouse emissions under control because we could end up with a world where we don't have the Great Barrier Reef - that would be an absolute tragedy."
Mr Henry wants the Federal Government to commit to the Kyoto agreement, and cut greenhouse pollution to save not just the Great Barrier Reef, but the huge impact it has on Australia's economy.
"But the crucial thing is we've only got a very narrow window of time to cut green house pollution so what we do in the next five to 10 years will effect the reef for the next 50 years," he said.
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Fly
Posts: 485
Date Joined: 04/02/06
While I might agree
that the dammage is of a great deal of concern, maybe the sky isn't actually falling?
Corals elsewhere do still spawn and that coral spawn is carried by the currents to settle on new reef elsehwere - that is the mechanism by which coral inhabits new places suited to it.
Anyones ever seen serious coral spawn would know it must go elsehwere.
I think the big problem is that algae takes over the bleached coral and stops coral spawn from getting a foothold.
BUT some coral deaths are attributable to "natural causes" and the organisms must have some coping mechanisms or they would likely have never survied this long anyway!
Would be better if it didn't happen, but might not be as bad as we are being led to believe IMHO!
Cheers!
Scaly
Posts: 22
Date Joined: 04/05/06
Lots of different viewpoints on this depending on who
Lots of different viewpoints on this...some may be pushing a bigger wheelbarrow than others
http://www.planetark.org/avantgo/dailynewsstory.cfm?newsid=5117
"The future for the Great Barrier Reef may not be as gloomy as a recent report claims," said Terry Done, senior principal scientist with the Australian government's AIMS.
"The biodiversity of coral reefs may give them greater resilience than the (Greenpeace) report gives them credit for," he said.
Bleaching occurs when coral becomes stressed and expels its life-giving microscopic plants called zooxanthellae. The plants provide the coral with food through photosynthesis.
AIMS examined 47 reefs which are part of the World Heritage-listed Great Barrier Reef system and found that, while inshore reefs had lost up to 75 percent of corals in the 1998 bleaching, reefs in deeper water were largely unaffected.
"The current state of coral is not as bad as you might be led to believe," AIMS project leader Hugh Sweatman told Reuters.
"In general, the reef is in good shape. The reefs which made up most of the world heritage area have shown net increases in hard coral in the past two years."
Fly
Posts: 485
Date Joined: 04/02/06
Put it in perspective
We need to put coral bleaching reports into perspective!
The above aerial view of a coral spawning event at the Houtman Abrolhos one march a couple years back gives "some idea" of the 'amount' of coral polyps (spawn) released by corals over the full moon in March each year!
This settles out on new areas and establishes repair work to reefs damaged by storms - tsunami's and other natural disturbance events!
It also helps repair things like craypot damage and anchor damage and even stuff Frank Prokop harps on about occasionally with regard to fin damage and hand damage to corals etc from Scuba divers.
In other words - it helps to repair natural distrbances and man made disturbances!
Need we distinguish between the two? (Man made and Natural?).
Man is not a product of nature??.
Myself, I believe that global warming is "bad" but then so are ice ages and anthing else that upsets my week!.
But if we accept than man and his influence on our environment are just another "natural disturbance event" - like tsunanmi's and earth quakes and meteor strikes etc...well - is the sky really falling if a bit of the GBR coral gets bleached? Nature has her coping mechanisms for disturbance events (natural or "man made" (if we must be so arrogant as to distinguise between them because we belive we are superior to mother nature because of our intellect and technology!).
As I undertstand it - when coral gets bleached, algae (sea weeds) can take hold and coral never gets a foothold again! Os so is stated the great concern about coral bleaching on reefs by the breed of todays "sky is falling, raving, sicophant eco-nazi's"!! ;o)
But doesn't that happen to reef damage occasioned by storms & tsunami's etc also? I.e. isn't it all just a part of natural cycling - or disturbance events (and why distinguish between them - isn't that arrogant of us in the extreme)?
It would be better if the world wasn't overfull with 6 billion people IMHO and if we as a species, didn't have such large effects (place such big strains) upon the earths ecosystems coping mechanisms, BUT - wo wants to be the one to decide to get rid af a few billion people to ease the pressure????
Anyone wanna step forward and volunteer to push the big red buttion???
OK - so, disturbance events happen (whether we need to further describe them as natural or man made is debateable) and it'd be nice if they didn't but they do so we need to get used to it!!
When they do - nature being as resourceful as she is, has mechanism's to cope and repair redress restore her ecosystems!!
If corals ALWYAYS were successful at establishing - would we have the oceanic algae's (Seeweeds!) at all?
Don't both corals and sea weeds both need a break every now and then to get established?
Isn't a disturbance event like warm water El Nino / cold water La Nina - just another cycling disturbace event that favours one organism over another? When the reverse happens (cold water) isn't the corals favoured?
Do we need to believe, that the sky is falling, when nature cycles this way or that, to correct imbalances within the earths ecosystems??
The Earth & Mother nature have been taking care of this planet an awful lot longer than since mankind came along! We are but a recent 'blow in', in geological earth age terms - and many many species before us came and went...
Maybe if we tax mother nature and the earth more than she can cope with, she will get rid of the 6 billion strong "human virus" the earth is currently plagued with in two shakes of a lambs tail!
Mother nature has her ways - she got rid of Tyranosaurus Rex and his mates and a few dodo birds -I find it hard to believe after the world wars and pandemics/ plauges that she couldn't get rid of a few Billion suplus souls in the form of us humans if we get ecologically 'out of control' to the point we threaten her survival as a virus might threaten us!
Look & learn, the processes go on around us every day and we are only just beginning to undertsand them!.
The 'dooms sayers' that predict the environmentl sky is falling, have a $ vested interest in scaring the community into pressuring politicians into funding their further ongoing research, so they can contiinue to live the life on the high seas in luxury research vessels diving the worlds reefs systems and otherwise living the Life of Riley!
We need to heed the signals, but the noises beng made by the eco green lobby, still largely sound like the biy who cried wolf to me!
But then, I'm a synic and not so easily fooled by the general press as some!;o)
That grey and pink cloud of coral spawn is out there circulating in the worlds oceans looking for somewhere good to settle - maybe some of it will get to the GBR's beleached spots and help re estabklish new corals!
Heres hoping!
Cheers!