A fifth of the planet's coral reefs are dead

[hongi]

...and we're to blame:

POZNAN, Poland (AFP) – Almost a fifth of the planet's coral reefs have died and carbon emissions are largely to blame, according to an NGO study released Wednesday.

The report, released by the Global Coral Reef Monitoring Network, warned that on current trends, growing levels of greenhouse gases will destroy many of the remaining reefs over the next 20 to 40 years.

"If nothing is done to substantially cut emissions, we could effectively lose coral reefs as we know them, with major coral extinctions," said Clive Wilkinson, the organisation's coordinator.

The paper was issued on the sidelines of the December 1-12 negotiations on a new global treaty on climate change, taking place under the UN flag.

Half a billion people around the world depend on coral reefs for food and tourism, according to a common estimate.

Experts say the coral die-off has several causes, including local pollution, overfishing and invasive species.

But, they say, rising ocean temperatures caused by the greenhouse effect, and acidification, caused by the ocean's absorption of carbon dioxide (CO2) from the atmosphere, are probably the biggest triggers.

"If nothing changes, we are looking at a doubling of atmospheric carbon dioxide in less than 50 years," said Carl Gustaf Lundin, head of the the global marine programme at the International Union for the Conservation of Nature, an umbrella network for more than a 1,000 NGOs and government groups.

"As this carbon is absorbed, the oceans will become more acidic, which is seriously damaging a wide range of marine life from corals to plankton communities and from lobsters to seagrasses."

Nearly half of global coral reefs are still healthy, but the overall downward trend shows no sign of stopping, the study found. It added, though, that the damage could be braked by strong conservation measures, such as properly policed marine parks.

[Samuel]

Coral bleaching, right?



I'm pretty sure the coral is screwed- there is no way to stop it right now. To bad... I always wanted to see the Great Barrier Reef.

[hongi]

I swam in (on? around?) the Great Barrier Reef, and it doesn't get much better than that. I recommended seeing it soon, it's probable that you'll never see it in it's pristine condition again.

[Erik von Nein]

Yeah, well, coral bleaching is cause by several things. The increased acidity is just the major one. There's also the heavy amounts of silt choking off light corals depend on, increased nutrients in the water from run off cause algal blooms which then also kill off the coral (they rely on clear, nutrient-poor waters). And, yeah, there's not a whole lot that can be done about it right now, short of that one guy's solution of dumping ass-loads of nutrients into the water causing increase microbe growth to absorb carbonic acid for their skeletons. I doubt that'd work, since the sheer volume of water we're talking about kind of precludes that.

Though, I wonder how much success it'd meet on a local scale ("local" meaning any expanse of reef).

Though, this disaster has nothing on the warming oceans causing the Great Undersea Conveyor Belt from ceasing to function. Not only with it mean massive die offs of any deep sea life but it'll also royally screw with temperature patterns everywhere. While the Atlantic air flow from the south helps to keep north-western Europe warm, the GUCB helps moderate the temperature quite a bit more.

It's pretty depressing to be a biologist sometimes.

[Alyrium Denryle]

Though, I wonder how much success it'd meet on a local scale ("local" meaning any expanse of reef).

It wont. The microbes get snapped up by every little nibbler in the sea, to no real benefit. One of those things that works great in a closed system, but not in the field.

Thing is, it isn't just coral. Everything that depends on coral, which are a shit ton of inverts and fish, are going to die off as well. Their free floating larva form a good chunk of the basis for the world's aquatic ecosystem as well, and with them gone, everything that feeds upon them via filter feeding will suffer.

It's pretty depressing to be a biologist sometimes.

Tell me about it.

Not to sidetrack, but what do you work with anyway?

[Erik von Nein]

It wont. The microbes get snapped up by every little nibbler in the sea, to no real benefit. One of those things that works great in a closed system, but not in the field.

Yeah, I kind of thought it wouldn't work. Oh, well.

Thing is, it isn't just coral. Everything that depends on coral, which are a shit ton of inverts and fish, are going to die off as well. Their free floating larva form a good chunk of the basis for the world's aquatic ecosystem as well, and with them gone, everything that feeds upon them via filter feeding will suffer.

Of course. The coral reefs are hugely important to the rest of the ocean's life. Top tier predators, like sharks, also use the coral reefs for food even if they don't predominantly live in them.

Also, every environment is going to suffer big time here. The corals are just the ones getting completely wiped out. But the kelp forests (also hideously important) are going to get pushed farther and farther north (what ones are being over fished to extinction, anyway) by rapidly heating waters, never mind places like the Gulf of Mexico which are, already, almost completely unusable by animals like gray whales, let alone the fish and invertebrates that actually live there year-round.

That's not even taking into account invasive kelp or algal species. Those are play merry hell with near-shore environments, though they at least appear to be contained in California.

Tell me about it.

Not to sidetrack, but what do you work with anyway?

As of right not volunteer work with the local bay (Morro Bay) protection groups while I get through college. If all goes according to plan (hah) I'll be working at Monterey Bay's various marine biology programs (hopefully deep sea research, but eh ...) while finishing up college there.

[Alyrium Denryle]

Also, every environment is going to suffer big time here. The corals are just the ones getting completely wiped out. But the kelp forests (also hideously important) are going to get pushed farther and farther north (what ones are being over fished to extinction, anyway) by rapidly heating waters, never mind places like the Gulf of Mexico which are, already, almost completely unusable by animals like gray whales, let alone the fish and invertebrates that actually live there year-round.

Oh god... I am amazed there is any life left in the Gulf, the Mississippi river is so polluted by agricultural runoff and industrial pollutants that it is essentially eutrophicating the ocean. Shit-tons of nitrogen, phosphorus etc that drift from MS to FL.

The sick part is, it would be relatively easy to recycle the agricultural waste, but no one wants to do it.

As of right not volunteer work with the local bay (Morro Bay) protection groups while I get through college. If all goes according to plan (hah) I'll be working at Monterey Bay's various marine biology programs (hopefully deep sea research, but eh ...) while finishing up college there.

Good luck. It is rather difficult to do deep sea stuff.

[Erik von Nein]

Oh god... I am amazed there is any life left in the Gulf, the Mississippi river is so polluted by agricultural runoff and industrial pollutants that it is essentially eutrophicating the ocean. Shit-tons of nitrogen, phosphorus etc that drift from MS to FL.

Yeah, that's what killed off quite a bit of the reefs in the gulf in the fist place. That used to be the #1 killer of reefs in general, until they noticed carbonic acid levels rising rapidly.

The sad thing is, the bay I was talking about earlier suffers massively from eutrophication and silt run-off. It's getting better, slightly, but there's still a ton of ranch and farmland that needs to be dealt with. Last I heard, though, the bay's eel grass beds are going to be completely gone in the next 40 years and, with it, a large portion of the fish in the area.

The sick part is, it would be relatively easy to recycle the agricultural waste, but no one wants to do it.

Yeah, it's pathetic really. Sure, it's added cost but it's added cost for the benefit of not completely wiping out life in the Gulf.

This is why I prefer ranchers, fishermen and farmers to be local, small-scale businesses. They're so much easier to work with and much more reasonable as a whole. What's been done in my area with fishermen, farmers and ranchers wouldn't be nearly as successful if they were all multi-national corporations (or even intra-national ones).

Good luck. It is rather difficult to do deep sea stuff.

Thanks. That's what I've heard, but I can handle the occasional sandwich tasting like fish after it's sat on the deck for 20 minutes.