CITES Makes Historic Decision to Protect Sharks and Rays

CITES victory for sharks and rays bannerCITES plenary today accepted Committee recommendations to list five species of highly traded sharks under the CITES Appendices, along with those for the listing of both manta rays and one species of sawfish.

We’re grateful to proponent governments for recognizing the value of thriving shark and ray populations, and for championing sound proposals,” said Ania Budziak, Project AWARE’s Associate Director. “We’re proud that the divers’ voice has contributed to achieving this key milestone in shark and ray conservation.”

See on www.sciencedaily.com

English: Manta Ray off Ishigaki Island in Sept...

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The Devastating Effects of Bottom Trawling

Video: The Devastating Effects of Bottom Trawling – Bottom trawling is laying waste to the precious ecosystems of the deep sea. Sigourney Weaver calls on delegates of the UN to take immediate action to stop this destruction.

Bottom Trawling Impacts On Ocean, Clearly Visible From Space

Bottom trawling, an industrial fishing method that drags large, heavy nets across the seafloor stirs up huge, billowing plumes of sediment on shallow seafloors that can be seen from space.As a result of scientific studies showing that bottom trawling kills vast numbers of corals, sponges, fishes and other animals, bottom trawling has been banned in a growing number of places in recent years. Now satellite images show that spreading clouds of mud remain suspended in the sea long after the trawler has passed.

But what satellites can see is only the “tip of the iceberg,” because most trawling happens in waters too deep to detect sediment plumes at the surface, say scientists speaking a symposium session called Dragnet: Bottom Trawling, the World’s Most Severe and Extensive Seafloor Disturbance at the American Association for the Advancement of Science 2008 Annual Meeting February 15. Speakers at the session include Dr. Elliott Norse, President of Marine Conservation Biology Institute in Bellevue WA; John Amos, President of SkyTruth in Shepherdstown WV, Dr. Les Watling, Professor of Zoology at the University of Hawaii in Manoa HI; and Susanna Fuller, Ph.D. Candidate in Biology at Dalhousie University, Halifax NS.

The Effect of Trawling the Seafloor for Ground...

The Effect of Trawling the Seafloor for Groundfish. (A) The coral community and seabed on an untrawled seamount. (B) The exposed bedrock of a trawled seamount. Both are 1,000–2,000 meters (1094–2188 yards) below the surface. (Photo credit: Wikipedia)

“Bottom trawling is the most destructive of any actions that humans conduct in the ocean,” said Dr. Watling. “Ten years ago, Elliott Norse and I calculated that, each year, worldwide, bottom trawlers drag an area equivalent to twice the lower 48 states. Most of that trawling happens in deep waters, out of sight. But now we can more clearly envision what trawling impacts down there by looking at the sediment plumes that are shallow enough for us to see from satellites,” he said.

“Bottom-trawling repeatedly plows up the seafloor over large areas of the ocean” said Mr. Amos. “Until recently, the impact was basically hidden from view. But new tools — especially Internet-based image sites, like Google Earth — allow everyone to see for themselves what’s happening. In shallow waters with muddy bottoms, trawlers leave long, persistent trails of sediment in their wake.”
Susanna Fuller studies impacts of trawling on sponges in the Northwest Atlantic Ocean. “Seafloor animals such as glass sponges are particularly vulnerable to bottom trawling,” said Ms. Fuller, a graduate student of Professor Ransom Myers. Dr. Myers, who died last year, had published a series of papers showing that overfishing has eliminated 90 percent of the world’s large predatory fishes and is devastating marine ecosystems.

“What is amazing is the level of damage these types of animals have suffered, after the cod fishery in Canada was closed. We immediately started trawling deeper with no restrictions, and continue to do so,” she said. “There are ways to catch fish that are less harmful to the world’s vanishing marine life. We need to start protecting the seafloor by using fishing gear, besides bottom trawls, especially in the deep sea. It’s the only thing left,” she said.

“For years marine scientists have been telling the world that fishing has harmed marine biodiversity more than anything else,” said Dr. Norse. “And it’s clear that trawling causes more damage to marine ecosystems than any other kind of fishing. Now, as the threats of ocean acidification and melting sea ice are adding insult to injury, we have to reduce harm from trawling to have any hope of saving marine ecosystems,” Dr. Norse said.

Scientific findings about trawling impacts have led to increasing restrictions on this industrial fishing method. In 2005, the General Fisheries Commission for the Mediterranean banned trawling in the Mediterranean Sea below depths of 1,000 meters, and the United States closed vast deep-sea areas off Alaska to bottom trawling. In 2006, the United Nations General Assembly began deliberations on a trawling moratorium on the high seas, which cover 45% of the Earth’s surface, and South Pacific nations effectively put an end to trawling in an area amounting to 14 percent of the Earth’s surface.

There are tens of thousands of trawlers worldwide. They fish for shrimp and finfishes. Some bottom trawling operations catch 20 pounds of “bykill” for every pound of targeted species.

Source:Bottom Trawling Impacts On Ocean, Clearly Visible From SpaceScienceDaily,  Feb, 2008

Ending Overfishing

Despite an increased awareness of overfishing, the majority of people still know very little about the scale of the destruction being wrought on the oceans.

An Ocean of Troubles

Overfishing, global warming and pollution threaten to transform the ocean—and perhaps life as we know it.

IN 1998 a rise in sea temperatures caused by El Niño, a periodic eastward surge of warm Pacific water, caused a mass bleaching of the world’s coral reefs, the permanent or temporary home of perhaps a quarter of all marine species. Up to 90% of the Indian Ocean’s technicoloured reefs turned to skeletal wastes, largely devoid of life. Had this happened to rainforests—coral’s terrestrial equivalent—a sea-change in attitudes to the environment could have been expected. But because this change occurred in the sea, the calamity drew remarkably little comment.
Traditional attitudes towards the sea, as something immutable and distant to humanity, are hugely out of date. The temperature change that harmed the corals was not caused by human activity; yet it was a foretaste of what man is now doing to the sea. The effects of overfishing, agricultural pollution and anthropogenic climate change, acting in concert, are devastating marine ecosystems. Though corals are returning to many reefs, there is a fair chance that in just a few decades they will all be destroyed, as ocean temperatures rise owing to global warming. The industrial pollution that is cooking the climate could also cause another problem: carbon dioxide, absorbed by the sea from the atmosphere, turns to carbonic acid, which is a threat to coral, mussels, oysters and any creature with a shell of calcium carbonate.

The enormity of the sea’s troubles, and their implications for mankind, are mind-boggling. Yet it is equally remarkable how little this is recognised by policymakers—let alone the general public. Killer sharks are a more appealing subject than algal blooms; though they are much less deadly. There is also a dearth of good and comprehensive books on a subject that can seem too complicated and depressing for any single tome. Callum Roberts, a conservation biologist, has now provided one.

He starts with a bold claim: that anthropogenic stresses are changing the oceans faster than at almost any time in the planet’s history. That may be putting it too strongly. Yet there is no quibbling with the evidence of marine horrors that Mr Roberts presents.

The Chagos is one of the few marine locations ...

The Chagos is one of the few marine locations in the world where there are almost no ongoing, direct human impacts over almost all of its areas. The marine reserve would serve as a reference site for global scientific research to aid in our understanding of such things as climate change, tropical marine ecosystems and the impacts of commercial fisheries.

Take overfishing. The industrialisation of fishing fleets has massively increased man’s capability to scoop protein from the deep. An estimated area equivalent to half the world’s continental shelves is trawled every year, including by vast factory ships able to put to sea for weeks on end. Yet what they are scraping is the bottom of the barrel: most commercial species have been reduced by over 75% and some, like whitetip sharks and common skate, by 99%. For all the marvellous improvements in technology, British fishermen, mostly using sail-power, caught more than twice as much cod, haddock and plaice in the 1880s as they do today. By one estimate, for every hour of fishing, with electronic sonar fish finders and industrial winches, dredges and nets, they catch 6% of what their forebears caught 120 year ago.

Overfishing is eradicating the primary protein source of one in five people, many of them poor. It also weakens marine ecosystems, making them even more vulnerable to big changes coming downstream.

For example, there is the matter of chemical pollution, mostly from agricultural run-off. This has created over 400 dead-zones, where algal tides turn the sea anoxic for all or part of the year. One of the biggest, at the mouth of the Mississippi Delta in the Gulf of Mexico, covers 20,000 square km (7,700 square miles) of ocean. An annual event, mainly caused by the run-off of agricultural fertilisers from 40% of America’s lower 48 states, it makes the one-off Deepwater Horizon oil-spill look modest by comparison.

Global warming is another problem. Hitherto, the sea has been a buffer against it: because the heat capacity of water is several times that of air, the oceans have sucked up most of the additional heat, sparing the continents further warming. Yet this is now starting to change—faster than almost anyone had dared imagine.

One effect of the warming ocean, for example, is to increase the density difference between the surface and the chilly deep, which in turn decreases mixing of them. That means less oxygen is making it down to the depths, reducing the liveability of the oceans. Off America’s west coast, the upper limit of low-oxygen water is thought to have risen by 100 metres. Where strong winds bring this water nearer to the surface, there are mass die-offs of marine life. Such events will proliferate as the climate warms.

This is a poor lookout for already put-upon fish. “Fish under temperature and oxygen stress will reach smaller sizes, live less long and will have to devote a bigger fraction of their energy to survival at the cost of growth and reproduction,” writes Mr Roberts. And that is before he gets to the effects of ocean acidification, which could be very bad indeed. Without dramatic action to reverse these processes, he predicts a catastrophe comparable to the mass extinctions of the Palaeocene-Eocene Thermal Maximum, when carbon-dioxide levels, temperature and ocean acidity all rocketed. He writes: “Not for 55m years has there been oceanic disruption of comparable severity to the calamity that lies just a hundred years ahead.” That would be hard to prove; it would be better not to try.

So what is to be done? Mr Roberts provides a hundred pages of answers, occupying roughly a third of the book. They range from the obvious—curbing carbon emissions—to technical fixes, like genetic improvements to aquaculture stocks. None is impossible; and Mr Roberts, almost incredibly, describes himself as an optimist. He writes, “We can change. We can turn around our impacts on the biosphere.” We had better do so.

See on www.economist.com

One Planet, One Ocean, One Chance …

This film was made for WCPA by world-renowned cinematographer Bob Talbot. This video clip enlightens us that we have only one ocean and it is in serious trouble! Together we can turn this around!

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