Demise of the Deep

With 71 percent of its surface area covered in water and its atmosphere wrapped in clouds of water vapor, the Earth is a unique oceanic realm. Besides containing the proper balance of chemicals and compounds necessary for the development of life, the oceans serve many functions essential for the survival of land-dwelling creatures. They absorb harmful radiation from the sun and distribute heat around the world via a system of underwater currents, working to maintain a stable climate. Scientists today still don't fully understand the workings of the deep. We know more about the lifecycle of stars and the surface of Mars than we do about our own ocean floor. Until the 1990s the general populace assumed that our rampant destruction of nature couldn't possibly affect the immensity of these vast interconnected ecosystems. In reality they aren't faring any better than the land.

Entire seas have been laid to waste imperiling the one billion people who depend on them for their protein needs. Likened to the clear-cutting of forests, overfishing is by far the most reported aspect of this ecocide. Recently, a research team led by Boris Worm and Ransom Myers of Dalhousie University in Halifax, Nova Scotia studied fishing log books dating back 50 years and concluded that nearly half of all ocean species have been lost to overfishing. The study also found that the size of ocean "hot spots", which were traditionally rich in a diverse array of fish species, have shrunk significantly. "Everywhere you go, in every ocean basin, our hot spots today are only relics of what was once there. It really hurts to see this," stated Dr Worm.

The fate of Canada's Newfoundland is a foreboding example of this greed run amuck. Five hundred years ago, explorer John Cabot returned from the waters around this remote island to Europe with stories of codfish that ran so thick they could be caught with wicker baskets hung over the side of a ship. Cod grew to six or seven feet and weighed as much as two hundred pounds. The shores were filled with an abundance of gigantic oysters and lobsters. Eight to twelve foot sturgeon ran through New England rivers from Hudson River to Hudson Bay. Today, Newfoundland's fish stocks have been demolished and strip-mined. The waters are as vacant and empty as the surrounding countryside, where massive unemployment led to an exodus of residents.

The cod, which survived in their current form for ten million years, met their match in 1951 with the emergence of a British ship known as the Fairtry. It was the world's first factory-freezer trawler. This multi-million dollar ship was equipped with all the technological achievements of World War II. It included on-board processing plants, automated filleting machines, a rendering factory, and gigantic freezers. It could fish all day, seven days a week, with radar, sonar and fish finders. The Fairtry could find and capture entire schools of fish with effortless efficiency. This ship was a modified version of the whaling technology that hunted the blue whale, the largest animal ever known, to the brink of extinction.

With the whales gone, these floating-factories were redeployed against the world's fish. These ships eventually reached sizes of 8,000 tons with nets 3,500 feet in circumference. In an hour they could bring in 200 tons of fish-twice as much as a 16th century ship caught in an entire season. By the 1970s almost every industrialized nation had a fleet. Because these massive trawlers needed large numbers of similarly sized fish, creatures of unwanted sizes and species were discarded. For every three tons of fish caught, one ton of "bycatch" was thrown overboard dead and dying. With larger commercial fish populations decimated, these gigantic ships are now moving lower down the food chain making it even harder for the larger fish to recover.

The destruction of essential costal spawning areas is exacerbating the problem. Most aquatic species rely on salt marshes, sea-grass meadows, mangroves, or kelp forests for survival during some part of their life cycle. Unfortunately, most of these areas tend to occupy valuable coastal real estate, and are replaced by golf courses, shrimp farms, marinas, and resorts. Worldwide development and pollution has degraded half of all coastal wetlands since 1900. The World Resource Institute estimates that just the loss of mangrove forests has translated into the disappearance of 4.7 million tons of commercial fish. Without these "nurseries of the sea" large numbers of marine organisms will not survive.

The advent of "dead zones," caused mainly by the nitrogen fertilizer run-off of large scale agricultural practices, isn't helping the situation either. Phytoplankton activity is limited by the nutrients available in the water, and excessive nitrogen leads to explosions of these microscopic organisms called "algae blooms." The aquatic grazers can't keep up and large amounts of dead algae fall to the ocean floor to be decomposed by bacteria-a process that consumes large quantities of oxygen. Sometimes so much oxygen is used in this process that everything else in the area must flea or face suffocation. This condition is called hypoxia.

For generations the Mississippi has been treated as an open sewer, and in Louisiana a 90-mile stretch of America's largest river has been dubbed "Cancer Alley." Home to 136 petrochemical plants and seven oil refineries, Cancer Alley's facilities produce close to a billion pounds of toxins a year. Louisiana leads the nation in toxic wastes released into surface waters, and it all flows into the Gulf of Mexico. The dead zone that appears annually in the Gulf can cover more than 7,000 square miles. The world's largest dead zone is in the Baltic, where sewage and nitrogen fallout from burning fossil fuels combine with fertilizers to over-enrich the sea. Nearly a third of the world's dead zones are around the United States, including an infamous one in Chesapeake Bay. They also surround the coasts of Europe and Japan, and have reached China, Brazil, Australia and New Zealand.

Invasive species are another more subtle but just as devastating type of pollution. When light on cargo, oceangoing tankers and container ships pump water into their holds to maintain their seaworthiness. This ballast water can contain dozens of plants and animals, most in the form of eggs, larvae, or juveniles. When this water is discharged halfway around the world, huge numbers of alien species are introduced to the surrounding environment. Some three thousand species are picked up in ballast water every day. Exotic invasions decimate ecosystems that have already been pushed to collapse by other stresses. Mnemiopsis leidyi, a type of jelly fish that will eat everything in its path, has snuffed out almost all life in the Black Sea after massive algae blooms, over fishing and pollution had destroyed just about everything else.

Meanwhile, global warming is rising worldwide ocean temperatures creating a myriad of additional problems. Warmer temperature is a key factor influencing where marine organisms can live, feed and reproduce. The warming of ocean surface layers is stressing populations and wiping out others that already live at the extremes of their temperature tolerance range. John McGowan of the Scripps Institution of Oceanography found that since 1977 warmer oceans have caused a 70 percent decline in zooplankton-tiny animals that directly or indirectly feed all higher life. Unusually warm ocean temperatures are melting glaciers that serve as vital habitat for artic life forms and are destroying coral reefs worldwide through a process called "coral bleaching." A 2004 report published by Queensland's Center for Marine Studies predicts that in 50 years 95 percent of Australia's Great Barrier Reef-one of the seven natural wonders of the world-will be without coral.

People are feeling the consequences as damaged marine systems are being prevented from providing their "free" services. Islands are washing away during tropical storms, formally stable shorelines erode and disappear, irregular weather endangers lives, and the quality and availability of seafood diminishes daily. Throughout history cultures around the globe have utilized the mysterious depths of the seas as a means of livelihood through fishing and transportation. The oceans were considered by many to be so magnificently large that they would provide an infinite supply of resources, as well as a receptacle for any amount of waste. An industrial revolution and several population explosions later, and it's now painfully clear that the oceans have reached their limit. A fatal combination of manmade forces are suffocating the Earth's womb before we can even figure out how it functions.

Written By Jason Glover

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