Ref: Kalau hutan bisa digundul seenaknya oleh rezim NKRI, maka tidak akan 
ketinggalan pula kekayaan di lautan akan dihabiskan. Hal ini harus disadari 
akibatnya bagi generasi mendatang, sekarang melarat dan dimiskinkan besok lusa 
akan lebih parah lagi keadaannya.

http://edition.cnn.com/2013/03/22/world/oceans-overfishing-climate-change/index.html?hpt=hp_c3

Overfished and under-protected: Oceans on the brink of catastrophic collapse
By Tom Levitt, for CNN 
March 22, 2013 -- Updated 1611 GMT (0011 HKT)
 The world's oceans are facing a bleak future, say marine scientists, unless we 
rebuild its abundance, variety and vitality. 
HIDE CAPTION
Marine life under threat
STORY HIGHLIGHTS
  a.. Healthy species-abundant oceans key to long-term human survival 
  b.. Overfishing and climate change threaten to trash ocean eco-system 
  c.. Bottom-trawling considered a highly damaging practice by marine 
scientists 
  d.. Ocean acidification caused by climate change threatening to kill off 
vital coral reefs 
(CNN) -- As the human footprint has spread, the remaining wildernesses on our 
planet have retreated. However, dive just a few meters below the ocean surface 
and you will enter a world where humans very rarely venture.

In many ways, it is the forgotten world on Earth. A ridiculous thought when you 
consider that oceans make up 90% of the living volume of the planet and are 
home to more than one million species, ranging from the largest animal on the 
planet -- the blue whale -- to one of the weirdest -- the blobfish.

Remoteness, however, has not left the oceans and their inhabitants unaffected 
by humans, with overfishing, climate change and pollution destabilizing marine 
environments across the world.

Many marine scientists consider overfishing to be the greatest of these 
threats. The Census of Marine Life, a decade-long international survey of ocean 
life completed in 2010, estimated that 90% of the big fish had disappeared from 
the world's oceans, victims primarily of overfishing.

"Anywhere you go and try to harvest fish with a trawl you are going to destroy 
any coral that lives there, and there is example after example of the damage 
that is done by trawlers
Ron O'Dor, senior scientist on the Census of Marine Life
Tens of thousands of bluefin tuna were caught every year in the North Sea in 
the 1930s and 1940s. Today, they have disappeared across the seas of Northern 
Europe. Halibut has suffered a similar fate, largely vanishing from the North 
Atlantic in the 19th century.

Opinion: Probing the ocean's undiscovered depths

In some cases, the collapse has spread to entire fisheries. The remaining 
fishing trawlers in the Irish Sea, for example, bring back nothing more than 
prawns and scallops, says marine biologist Callum Roberts, from the UK's York 
University.

"Is a smear of protein the sort of marine environment we want or need? No, we 
need one with a variety of species, that is going to be more resistant to the 
conditions we can expect from climate change," Roberts said.

The situation is even worse in south-east Asia. In Indonesia, people are now 
fishing for juvenile fish and protein that they can grind into fishmeal and use 
as feed for coastal prawn farms. "It's heading towards an end game," laments 
Roberts.

Trawling towards disaster

One particualar type of fishing, bottom-trawling, is blamed for some of the 
worst and unnecessary damage. It involves dropping a large net, around 60 
meters-wide in some cases, into the sea and dragging it along with heavy 
weights from a trawler.

Marine conservationists compare it to a bulldozer, with the nets pulled for as 
far as 20km, picking up turtles, coral and anything else in their path. The 
bycatch, unwanted fish and other ocean life thrown back into the sea, can 
amount to as much as 90% of a trawl's total catch.

Upwards of one million sea turtles were estimated to have been killed as 
bycatch during the period 1990-2008, according to a report published in 
Conservation Letters in 2010, and many of the species are on the IUCN's list of 
threatened species.

Campaigners, with the support of marine scientists, have repeatedly tried to 
persuade countries to agree to an international ban, arguing that the 
indiscriminate nature of bottom-trawling is causing irreversible damage to 
coral reefs and slow-growing fish species, which can take decades to reach 
maturity and are therefore slow to replenish their numbers.

Opinion: Deep sea fishing is 'oceanocide'

"It's akin to someone plowing up a wildflower meadow, just because they can," 
says Roberts. Others have compared it to the deforestation of tropical 
rainforests.

Bottom-trawling's knock-on impacts are best illustrated by the plight of the 
deep-sea fish, the orange roughy (also known as slimeheads) whose populations 
have been reduced by more than 90%, according to marine scientists.

"The disturbing truth is that humans are having unrecognized impacts on every 
part of the ocean, and there is much we have not seen that will disappear 
before we ever get a chance
Ron O'Dor, marine biologist
Orange roughys are found on, or around, mineral-rich seamounts that often form 
coral and act as feeding and spawning hubs for a variety of marine life.

"Anywhere you go and try to harvest fish with a trawl you are going to destroy 
any coral that lives there, and there is example after example of the damage 
that is done by trawlers," says Ron O'Dor, a senior scientist on the Census of 
Marine Life.

"If I ruled the world, they would be banned, they're just such a destructive 
method of catching fish. Fishermen have other methods, such as long-line, that 
cause far less damage.

"The disturbing truth is that humans are having unrecognized impacts on every 
part of the ocean, and there is much we have not seen that will disappear 
before we ever get a chance," says O'Dor, who is also a professor of marine 
biology at Dalhousie University in Halifax, Canada.

Acid test for marine species 

At the same time fisheries and vital marine ecosystems like coral are being 
decimated, the oceans continue to provide vital services, absorbing up to one 
third of human carbon dioxide emissions while producing 50% of all the oxygen 
we breathe.

Hi-res gallery: Extraordinary creatures of the Great Barrier Reef

But absorbing increasing quantities of carbon dioxide (CO2) has come at a cost, 
increasing the acidity of the water.

"The two worst things in my mind happening to oceans are global warming and 
ocean acidification," says O'Dor, "They're going to have terrible effects on 
coral reefs. Because of acidification essentially, the coral can't grow and 
it's going to dissolve away."

The ocean has become 30% more acidic since the start of The Industrial 
Revolution in the 18th century and is predicted to be 150% more acidic by the 
end of this century, according to a UNESCO report published last year.

"There's a coral reef off Norway that was discovered in 2007 and it's likely to 
be dead by 2020," says O'Dor.

"The problem is that the acidification is worse near the Poles because low 
temperature water dissolves more acid. Starting from the Pole and working south 
these reefs are going to suffer extensively."

Currents estimates suggest 30% of coral reefs will be endangered by 2050, says 
O'Dor, because of the effects of ocean acidification and global warming.

Higher acidity also disrupts marine organisms' ability to grow, reproduce and 
respire. The Census of Marine Life reported that phytoplankton, the microscopic 
plants producing most of the oxygen from the oceans, have been declining by 
around 1% a year since 1900.

"We need to fish less and in less destructive measures, waste less, pollute 
less and protect more
Callum Roberts, Marine biologist
The falling numbers of smaller, but lesser known species and plant life has 
significant impact further up the marine food chain. For example, seabirds 
which used to visit and breed on Spitsbergen -- a Norwegian island near the 
Arctic -- are being wiped out because of changes in their previously abundant 
food sources.

Bringing law and order to ocean protection

"There's a real lack of public and political awareness of these issues," says 
Alex Rogers, professor of conservation biology at the UK's Oxford University.

"They're too big to understand in economic terms. We can put a value on the 
loss of fishing, but how can we put a value on oxygen production or the 
absorption of carbon dioxide?" he says.

The problem is that most of the world's ocean is located outside of 
international law and legal control. Any attempts to implement rules and 
regulation come with the problem of enforcement, says Rogers, who is also 
scientific director of the International Program on State of the Ocean (IPSO).

Marine conservationists estimate that at least 30% of the oceans need to be 
covered by marine protected areas, where fishing and the newly emerging 
deep-sea mining of valuable minerals on the seabed, is banned or restricted.

Callum Roberts, who helped form the first network of marine protected areas in 
the high seas in 2010, says on their own they are not enough.

"I could sum it up as: we need to fish less and in less destructive measures, 
waste less, pollute less and protect more," says Roberts.

"This change of course will see us rebuild the abundance, variety and vitality 
of life in the sea which will give the oceans the resilience they need to 
weather the difficult times ahead. Without such action, our future is bleak."


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