Facts and Details

OCEANIC POLLUTION

garbage in the sea off Japan More than two out of every five people lives 60 miles or less from a sea coast. These people have a profound effect on the oceans and marine ecosystems. Many tourist resorts are built as close to the sea as possible. Garbage, untreated sewage and waste from construction of building tourist resorts is threatening the beauty and ecology of many small island nations.

Pollution has also taken a heavy toll, rendering the oceans less resilient to climate change. Runoff from nitrogen-rich fertiliser, killer microbes, and hormone-disrupting chemicals, for example, have all contributed to the mass die-off of corals, crucial not just for marine ecosystems but a lifeline for hundreds of millions of people too.

Most sea pollution comes from off from the land. The main sources are waste from farm animals, fertilizers, human sewage, eroded soil, runoff from irrigated fields and lawns with fertilizers and pesticides, runoff from urban landscape containing motor oil, sediment and animal wastes, overtaxed sewage and septic systems, air -borne particles from factories and vehicles dumped in the sea. River sediments contain petroleum runoff and mercury from power plant emissions.

Much of the pollution is in the form of basic nutrients such as nitrogen, carbon, iron and phosphoreus compounds. Millions of tons of carbons dioxide and nitrogen oxide, produced by burning fossils fuels enter the ocean every day.

Sources of maritime pollution: 1) sewage (30 percent); 2) farm run off (20 percent); 3) air pollutants (20 percent); 4) industrial wastewater (10 percent); 5) maritime transportation (10 percent); 6) offshore oil (6 percent); 7) litter (5 percent).

Famous 1971 Minamata Bay photo
by William Eugene Smith
of mercury poisoning Websites and Resources: National Oceanic and Atmospheric Administration noaa.gov/ocean ; Smithsonian Oceans Portal ocean.si.edu/ocean-life-ecosystems ; Ocean World oceanworld.tamu.edu ; Woods Hole Oceanographic Institute whoi.edu ; Cousteau Society cousteau.org ; Montery Bay Aquarium montereybayaquarium.org

Websites and Resources on Fish and Marine Life: MarineBio marinebio.org/oceans/creatures ; Census of Marine Life coml.org/image-gallery ; Marine Life Images marinelifeimages.com/photostore/index ; Marine Species Gallery scuba-equipment-usa.com/marine

Websites and Resources on Coral Reefs: Coral Reef Information System (NOAA) coris.noaa.gov ; International Coral Reef Initiative icriforum.org ; Wikipedia article Wikipedia ; Coral Reef Alliance coral.org ; Global Coral reef Alliance globalcoral.org ; Coral Reef Pictures squidoo.com/coral-reef-pictures ; The Global Coral Reef Monitoring Network; the International Coral Reef Action Network.

Dead Zones and Other Effects of Pollution

Dead zones are areas where there is so much algae and bacteria that all the oxygen is sucked out of the water making it impossible for most life forms to exist. They exist in different spots around the globe. They create tons and tons and bacteria and algae. Few organism can live on them other than jellyfish. Fertilizer run off of and sewage seem to be big contributors to their creation. In some places swarms of jellyfish and poisonous bacteria that first appeared 2.7 billion years ago are taking over.

Dead zones increased by a third between 1997 and 2007. More than 400 dead zones, with a combined area of 246,000 square kilometers— an area about the size of New Zealand—were identified in 2007. Large ones have occurred in the Black Sea, Baltic Sea, the East China Sea, and the Gulf of Mexico, with one caused by algae located at the mouth of the Mississippi River. Another large one began off of Oregon and spread northward to Washington and southward to California. Many of them are blamed on fertilizer run off. They rarely happen in nature, without some kind of push from mankind.

One study found that one in 20 people who go in the sea around the world get sick from untreated water. In some places coastal waters are so polluted that people who swim in them risk getting diarrhea-causing gastrointestinal illnesses and sinus and upper respiratory infections. Most problems occur if the water is swallowed. Skin contact can result in rashes and infections of open wounds. In the worst cases people who stay in tainted water too long can contact viral myocarditis, a dangerous inflammation of the heart muscle.

Mercury and the Sea

Mercury in the food chain Coal-fired power plants are the primary source of atmospheric mercury. As particles it can fall quickly to earth but as an aerosol it can float for hundreds or even thousands of kilometers and fall all over the globe. When mercury falls into the sea or other waterways, bacteria can transform it into highly toxic methyl mercury, which is absorbed in very minute amounts by plankton, shellfish anchovies, sardines and other small fish, which in turn pass it up the food chain.

Each time a large fish consumers its prey, the mercury from the smaller fish lodge in the tissues of the larger fish. At the top of the food chain, fish such as mackerel, tuna, swordfish and sharks—as well as dolphins and whales—can have thousands of times more mercury than sardines or shellfish can. High concentration of mercury are also found in land animals that feed on fish such as eagles, loons, mink, otters and alligators.

Mercury is a dangerous heavy metal linked to health problems with children and birth defects and brain deformities. One of the problems with eating fish though is that many fish that are said to be healthy are also high mercury. Fish at the top of the food chain such as sharks, king mackerel, tilefish and swordfish have the highest mercury levels. Tuna has moderate amounts. Albacore turn has ore than light tuna. The levels in salmon are low. Studies have show that people who eat a lot of whale sometimes have high levels of mercury.

Oil Spills in the Ocean

Oil spills can cause big maritime disasters but the effects are often relatively temporary. The oceans are big enough so that most pollution and oil spills are eventually dispersed. Oil platforms some distance from shore offer a refuge for many marine organisms. Platforms and sunken ships create artificial reefs.

After the oil spill in the Gulf of Mexico in 2010 the government tested dozens of samples of flesh from fish and shrimp caught in the region. The tests begin with a sniff — trained experts smell the flesh, testing for crude or the Windex-like odor of chemical dispersants. Then, the samples are tested chemically for oil; there is no chemical test for dispersants. Of the 3,500-plus samples taken during the spill, officials say none contained enough oil or dispersant to be harmful to people. [Source: David A. Fahrenthold and Juliet Eilperin, The Washington Post, August 16, 2010]

Expert say fish and shrimp don't tend to absorb dispersants and that their bodies tend to break down the toxic components of oil. The chief worry about oil-tainted food is not that it will kill unsuspecting diners. Kraemer said even if such food wound up on a plate, it would smell so oily that diners probably wouldn't eat it. "If, however, you manage to choke it down, then the most common reaction would be a nausea or vomiting reaction," Kraemer said.

Ocean Debris

Debris from the 2011 tsunami in Japan Scientists say, wind and ocean currents eventually will push some of the massive debris from Japan’s tsunami and earthquake onto the shores of the U.S. West Coast. The floating debris will likely be carried by currents off of Japan toward Washington, Oregon and California before turning toward Hawaii and back again toward Asia, circulating in what is known as the North Pacific gyre, said Curt Ebbesmeyer, a Seattle oceanographer who has spent decades tracking flotsam. “If you put a major city through a trash grinder and sprinkle it on the water, that’s what you’re dealing with,” he said. [Source: AP, March 2011]

Ebbesmeyer first became interested in flotsam when he heard reports of beachcombers finding hundreds of water-soaked shoes in Washington, Oregon and Alaska. An Asia cargo ship bound for the U.S. in 1990 had spilled thousands of Nike shoes into the middle of the North Pacific Ocean. He was able to trace serial numbers on shoes to the cargo ship, giving him the points where they began drifting in the ocean and where they landed. The oceanographer also has tracked plastic bath toys — frogs, turtle, ducks and beavers — that fell overboard a cargo ship in 1992 in the middle of the Pacific Ocean and were later found in Sitka, Alaska.

Only a small portion of that debris will wash ashore, and how fast it gets there and where it lands depends on buoyancy, material and other factors. Fishing vessels or items that poke out of the water and are more likely influenced by wind may show up in a year, while items like lumber pieces, survey stakes and household items may take two to three years, he said.

Seas of Trash

Debris from the 2011 tsunami in Japan Mariners report seeing huge floating masses of trash in the middle of the ocean, particularly around the center gyres (circular current systems) and places where ocean currents and warm and cold water converge.

In the eastern Pacific between Hawaii and the West Coast of the United States is a mass of trash called the Eastern Garbage Patch that is twice the size of Texas and comprised of trash from both the Americas and Asia. In the western Pacific between Guam and southern Japan is another mass of trash, called the Western Garbage Patch and comprised of trash from both the Americas and Asia. One yachtsman who floated through the patch told the Los Angeles Times, “Every time I came to the deck, there was trash floating by. How could we have fouled such a huge area? How could this go on for a week?”

About 90 percent of the trash in these garbage patches is plastic and 80 percent is from the land. The rest comes from ships. Curtis Ebbsesmeyer, a Seattle-based oceanographer and expert of oceanic trash, told the Los Angeles Times: the masses of trash move in a clockwise direction and “move around like a big animal without a leash.When it gets close to an island, the garbage patch barfs, and you get a beach covered with this confetti of plastic.”

Studies have shown that trash dumped off the east coast of Asia and the west coast United States is still floating within a couple hundred kilometers of the coast after six months. After that time it starts to get carried away by major currents. After six years it collects in areas where the surface water contains six times more plastic than plankton biomass. A computer model of trash from Asia shows that after six months it was well on its way to the United States. By two years it had collected in the Eastern Garbage Patch. Two years later more had accumulated in the garbage patch and some had spun off and was heading to Asia. By seven years most was trapped in one of the two garbage patches, where it can remain trapped for decades.

Floating Plastic and Its Affects on Marine Life

All sorts of human debris floats around in the oceans and washes up on beaches. Often there is more junk on the beaches than sea shells.

Plastic is particularly dangerous and troublesome because it takes so long to break down. Plastic bags and flotsam endanger a number of marine creatures. Sea birds have been found with bottle caps and plastic in their stomach. Seals have gotten trapped is six-pack holders. Turtles have choked on plastic bags they mistook for jellyfish. Plastic also provides a means for destructive sea worms, barnacles and mollusk to hitch hike across the oceans. An estimated 1 million seabirds choke or become entangled in plastic nets or other debris every year. An estimated 100,000 seals, sea lions, whales, dolphins, other marines mammals and sea turtles die from floating plastic annually.

One study found that 40 percent of albatross chicks on Midway Atoll die from starvation and dehydration related to eating plastic garbage. Examinations of their stomach reveal colored bottle caps, gold tees, combs, fishing lines, spray nozzles, toothbrushes, cigarettes lighters, toy soldiers, brushes, Lego bricks, clothes pins, fishing lures and syringes that their parents mistook for food and regurgitated in the chick’s mouths. This has occurred even though Midway is situated in the middle of the Pacific, far from any industrial zones or population center, and has only a few people living on it

About 10 million tons of plastic is dumped into the world’s oceans every year. Spinning wind and air currents cause much of this to accumulate in vast quantities in the garbage patches in middle of each of the world’s five great oceans. Although plastic takes considerable time to degrade it is broken up by waves. But this seems to make matters worse as small pieces of plastic act as sponges for other pollutants such as mercury, DDT and PCBs. Small colored pieced of plastic are called “mermaid’s tears.” They are eaten by fish as well as birds. Toxins in the plastic work their way through the food chain.

To draw attention to huge amount of plastic floating around in the world’s ocean. David de Rothschild, a young bearded activist from the famous banking family, constructed an 18-meter-long boat from 12,500 plastic bottles and sailed it across the Pacific. Marine biologist Marcus Eriksen and oceanographer Joel Paschal had a similar aim in mind with vessel made from 15,000 plastic bottles held together with recycled nets.

Red Tides

Phytoplankton bloom in the Baltic Sea in 2001 Red tides are dense blooms or massive concentration of oxygen-consuming microscopic algae that grow and spread at a great speed. Despite their name, most of the time they are not red (although they can be). They are usually different shades of brown and can be bright green.

Red tides kills fish and other aquatic life through suffocation by depriving them of oxygen and producing toxins that can paralyze marine life. Once a red tide reaches critical mass, there is little that anyone can do other wait for it to end. A red tide can last anywhere from a few days to a few months. They are usually seasonally, typically occurring the fall in temperate climates.

Red tides are caused in part by plankton reproducing itself in large quantities due to large amounts and a steady supply of the nutrients nitrogen and phosphorous in the water. Sometimes red tides occur naturally, especially in places like the Gulf of Mexico where there is less water movement than in the Atlantic or Pacific. Often times, however, they are caused by the dumping of large amounts of waste water and sewage into the sea bay and waterways leading into the sea. When a red tide is at its peak, a liter of sea water may contain 10 million algae cells.

Red tides can poison seafood and cause the closing of beaches. Eating shellfish tainted by a red tide can cause food poisoning, vomiting and other nastiness and produce airborne toxins that cause throat and eye irritation, coughing, bloody noses and asthma fits. When red tides hit some coastal areas all events are cancelled and residents are encouraged to wear surgical masks. Sewage, industrial run off, urban pollution, storm run off, farming wastes, mining tailings, ranch run offs, and fertilizers can contribute to the development of a red tide.

Phytoplankton bloom in the North Sea Red tides kill everything from sea turtles to fish to horseshoe crabs. Sometimes they cover vast areas of the ocean surface and can extend down to the ocean floor and kill sponges, coral and starfish. Not all red tides are the same. Different kinds can be caused be caused by different species of algae.

A lack funds keeps many countries from tackling the problem aggressively. In some places they tried to minimize the damage caused the algae blooms by pumping oxygen in the water and containing blooms by adding clay which acts as a magnet for algae.

Red tides can also affect animals up the food chain. Sick and dead sea lions, dolphins and pelicans have been linked to ingestion of fish and shellfish with high levels of domoic acid which builds up in the creatures during red tides and animals that eat them. Some of pelicans who consumed it, scientists said, literally have fallen out of the sky dead.

Jellyfish Swarms

In recent years huge swarms of jellyfish with numbers unseen before have been showing in places around the globe—from Spain to New York to Hawaii to Australia to Japan—where they hadn’t been seen before with a frequency and timing that are so alarming that some scientists suggest they may be a sign that the oceans are in decline. [Source: New York Times]

One swarm that hit beaches in Barcelona left 300 people needing treatment for stings and sent 11 to the hospital. Dr. Joseph-Maria Gili, a leading Spanish jellyfish expert, told the New York Times, “These jellyfish near the shore are a message the sea is sending is, saying, ‘Look how badly you are treating me.’” An offshore swarm of Pelagia noctiluca —an iridescent purplish jellyfish that issues a nasty sting—more than 1.6 kilometers long was spotted off Murcia, Spain.

Jellyfish swarm often appear in seas that have been overfished. They can make matters worse by feeding on larvae and eggs and competing for food such as zooplankton. According to a report by the National Science Foundation: “Human-caused stresses including global warming and overfishing, are encouraging jellyfish surpluses in many tourist destinations and productive fisheries.”

Fishermen are also feeling the strain. Many of them complain when they pull up their nets they are often filled more with jellyfish than with fish.

Echizen jellyfish—nasty creatures that can weigh up to 200 kilograms and reach a size of two meters in diameter—have caused havok in the Japanese fishing industry, particularly in the Sea of Japan off of Fukui, Shimane and Ishikawa Prefecture in western Honshu. The jellyfish have brown poisonous tentacles that kill fish and cause them to lose their color. Their huge numbers spoils fish catch and fouls fishing nets with a nasty smell. Their massive weight tears the nets when they are pulled out of the water.

The damage to the fishing industry has been in the tens of billions of yen. On fisherman told the Yomiuri Shimbun, “The nets were fouled by hundreds of jellyfish as soon as they were put out. There was little room for other fish, The fish that touched the tentacles of the jellyfish turned white, and the retail value of the fish is reduced to zero.”

The jellyfish population explosions have been blamed on global warming, increased nutrients in the water, and overfishing of jellyfish competitors. In the old days Echizen jellyfish disappeared by the time the autumn fishing season peaked. But warmer waters, perhaps caused by global warming, have caused the jellyfish to stick around longer than in the past. Some blame China for the problem, saying the jellyfish originate in waters off the coast China and their growth has been triggered by pollutants dumped in the sea.

See Jellyfish Blooms Under Jellyfish

Addressing Global Warming Improving Conditions of the Sea

Boris Worm of Dalhousie University in Halifax said, the problem “is not too large to turn around. It can be done, but it must be done soon. We need to shift from single species management to ecosystem management. It just requires a big chunk of political will to do it.” His team called for new marine reserves, better management to prevent overfishing and tighter controls on pollution.

Some see the Reducing Emissions from Deforestation and Forest Degradation (REDD) agreement, a global warming agreement hammered out in Copenhagen in December 2009, as a model tackling problems related to climate change and the sea. One of the key components of the program is the compensation of developing countries for preserving forests, peat soils, swamps and fields that absorb carbon dioxide. An similar a agreement that would address global warming and the sea would offer compensation to developing countries for protecting coral reefs. Mangrove swamps and other oceanic environment.

Progress has been made reducing the amount sewage and other pollution entering the sea.

Marine Reserves

Coral reef at Palmyra Setting up marine reserves is seen as major means of saving the world’s oceans. In 2009, in the closing weeks of his term, U.S. President George W. Bush, who was not well known for his environmental record, established the largest marine conservation area in U.S. history when he declared a 505,800 kilometer protected area in Pacific Ocean that included the Mariana Trench , and areas around islands in Marianas, Samoa and near the equator. In 2006, he also created the largest marine reserve in the world— the Hawaiian Islands Marine National Monument, a 138,000-square-mile reserve in an area of unspoiled reefs and shoals neat the Hawaiian Islands. The area covers an area larger than all the national parks in the United States combined.

Scientists have called for the creation of a network of marine parks and protecting more ocean areas. Only 0.5 percent of the oceans are protected, compared to about 12 percent of the Earth’s land area. Most protected areas are close to shore such as the Great Barrier Reef, waters around the Galapagos Islands or places in the Mediterranean.

Image Sources: 1) NOAA 2) William Eugene Smith

Text Sources: Mostly National Geographic articles. Also the New York Times, Washington Post, Los Angeles Times, Smithsonian magazine, Natural History magazine, Discover magazine, Times of London, The New Yorker, Time, Newsweek, Reuters, AP, AFP, Lonely Planet Guides, Compton’s Encyclopedia and various books and other publications.

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© 2009 Jeffrey Hays

Last updated March 2011