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11.2 What Marine Environmental Problems Are Associated with Petroleum Pollution? 349 50% mortality rate, then concentration limits are established for the discharge of the pollutant into coastal waters. There are several drawbacks to using a specific environmental bioassay to draw general conclusions about a pollutant. One shortcoming is that it does not predict the long-term effect of pollution on marine organisms. Another is that it does not take into account how pollutants may combine with other substances to create new types of pollutants. In addition, environmental bioassays are often time consuming, laborious, and organism-specific and so may result in data that isn’t applicable to other species. The Issue of Waste Disposal in the Ocean Waste disposal facilities on land (such as landfills) have limited capacities that are already being exceeded in many cases. Should additional waste be discarded in the open ocean? Unlike coastal areas, the open ocean has mixing mechanisms (waves, tides, and currents) that distribute pollutants over a wide area—including an en- tire ocean basin. Diluting pollutants often renders them less harmful. On the other hand, do we really want to distribute a pollutant across an entire ocean without knowing what its long-term effects might be? Some experts believe that we should not dump anything in the ocean, while others believe that the ocean can continue to be a repository for many of soci- ety’s wastes, as long as proper monitoring is conducted. Unfortunately, there are no easy answers and the issues are complex. What is clear is that more research is needed to determine how various types of pollution are affecting the ocean and its inhabitants. RECAP The ocean has become a global repository for much of the waste humans generate. Marine pollution is difficult to define but includes any substance introduced by humans that is harmful to the marine environment. CONCEPT CHECK 11.1 Explain how pollution is defined. 1 Examine the World Health Organi- zation’s definition of pollution. Why does it need to be so specific? 2 What is an environmental bioas- say? What are some drawbacks to using an environmental bioassay to determine whether or not a substance should be classified as a pollutant? 3 From memory, define pollu- tion. Then consider these items and determine whether each one is a pol- lutant based on your definition (and refine your definition as necessary): a. Dead seaweed on a beach b. Natural oil seeps c. A small amount of sewage d. Warm water from a power plant dumped into the ocean e. Sound from boats in the ocean 11.2 What Marine Environmental Problems Are Associated with Petroleum Pollution? Petroleum ( petra = rock, oleum = oil), which is more commonly called oil , is a naturally occurring liquid composed of hydrocarbons and other organic com- pounds. Underground petroleum deposits are highly valued for their energy con- tent and are recovered mostly through drilling. Once oil is collected, it is sent to a refinery via pipeline or tanker. As a result, oil spills into the ocean are a fact of our modern oil-powered economy. Some oil spills result from oil extraction. Other spills result from loading or unloading accidents or tanker collisions. Still others are caused by oil tankers running aground, as in the case of the 1989 oil spill from the Exxon Valdez tanker in Prince William Sound, Alaska. Let’s examine some of these examples. 11.1 Squidtoons https://goo.gl/9SvLVo M11_TRUJ3545_12_SE_C11.indd 349 12/16/15 8:00 PM

THE 2010 GULF OF MEXICO DEEPWATER HORIZON OIL SPILL O n April 20, 2010, the Deepwater Horizon , an offshore drilling platform operating in the Gulf of Mexico by British Petroleum (BP), was completing the final stages of drilling a deep oil well known as Macondo. The floating platform was located about 80 kilometers (50 miles) off the coast of Louisiana and in 1500 meters (5000 feet) of water beyond the edge of the continental shelf. Unexpectedly, it received a “kick” from a large bubble of natural gas that was under high pressure at the bottom of the well 4 kilometers (2.5 miles) beneath the sea floor. The blowout preventer on the sea floor failed, and the natural gas bubble rushed to the drilling platform, which exploded and caught fire (see the chapter-opening photo), killing 11 crew members. Two days after the explosion, the Deepwater Horizon sank, leav- ing the well gushing crude oil at the seabed at a rate of about 9 million liters (2.4 million gallons) per day ( Figure 11A ). Three months later, an underwater robotic vehicle was finally able to cap the well, but the amount of oil released became the world’s second-largest oil spill (the world’s largest accidental spill into the ocean) and by far the largest oil spill in U.S. waters. In all, nearly 795 million liters (210 million gallons) of oil were released from the well. A deluge of chemical dispersants—detergent-like solvents designed to break up the oil but considered more toxic to marine life than the oil itself—were applied both at the surface and in deep water. Scientists estimate that BP removed about a quarter of the oil, most of it recovered directly from the well, burned at sea, or skimmed by boats. Another quarter of the oil evaporated or dissolved into scattered molecules. And a third quarter was either naturally dispersed in the water as small droplets (which might still be toxic to some organism) or chemically dispersed. But the last quarter—around five times the amount released by the Exxon Valdez —hasn’t been fully accounted for; this oil is called residual oil . Some scien- tists suggest that the majority of it formed slicks or sheens on the water (Figure 11A), washed onto local beaches and marshes, and accumulated as tar balls on the sea floor. Other scientists suggest that some oil never made it to the surface; instead, the oil formed diffuse plumes more than 1000 meters (3300 feet) below the surface and likely dispersed into the ocean, was biodegraded by microbes, or sunk to the sea floor as tar mats. Even years later, it’s still not clear what happened to the missing oil. Fortunately, most of the oil remained offshore, where wave energy combined with oxygen, sunlight, and the Gulf’s abundant oil-eating bacteria were able to naturally bio- degrade it. Some of the oil, however, washed onto local beaches and salt marshes, fouling the shore and killing marine animals. The oil that sank to the bottom and became en- trained in low-oxygen sediments, like those on the sea floor—or a marsh—can hang FOCUS ON THE ENVIRONMENT DIVING DEEPER 11.1 around for decades, degrading the environ- ment. The cost of the cleanup, which will be funded by BP and its partners over the next 20 years, is estimated to exceed $40 billion. Birds, sea turtles, marine mammals, fish, and shellfish were some of the most affected marine organisms. Local fisheries were shut down after the spill but have been reopened since. It is unknown how this vast release of oil and chemical dispersants will affect marine organisms and the Gulf ecosystem, especially over time. As a tragic example, more than 1300 bottlenose dolphins ( Tur- siops truncatus ) washed up dead in the Gulf of Mexico between 2010 and 2012 with lung and adrenal-gland lesions that are consis- tent with exposure to petroleum compounds. Long-term studies are under way that will reveal how much damage the spill has done to the Gulf’s marine life. Figure 11A The 2010 Gulf of Mexico oil spill. Gulf of Mexico 90°W 80°W 30°N 25°N 85°W FLORIDA GEORGIA ALABAMA MISSISSIPPI LOUISIANA New Orleans Biloxi Mobile Pensacola Location of Deepwater Horizon oil drilling platform Extent of oil spill Map showing the extent of the 2010 Gulf of Mexico Deepwater Horizon oil spill. Oil washing ashore at Fourchon Beach, Louisiana. Aerial view of a ship passing though an oil slick. GIVE IT SOME THOUGHT 1. Describe what happened to the spilled oil from the 2010 Gulf of Mexico Deepwater Horizon oil spill. Why was it fortunate that the location of the oil spill occurred offshore? M11_TRUJ3545_12_SE_C11.indd 352 12/16/15 8:00 PM

11.2 What Marine Environmental Problems Are Associated with Petroleum Pollution? 355 Figure 11.8 Sources of oil to the oceans. Of worldwide oil to the oceans, 47% comes from natural seeps, while 53% comes from human sources. Of all human sources, 72% comes from petroleum consumption activities, such as individual car and boat owners, non-tank vessels, and runoff from increasingly paved urban areas. Surprisingly, combined petroleum transportation and extraction account for only 28% of all human-caused spilled oil. Natural seeps 47% Petroleum consumption 72% Petroleum extraction 6% All sources Human sources Petroleum transportation 22% Human sources 53% Human sources account for only about half of all oil entering the oceans. spill. The resulting cleanup rate was more than twice the rate that occurs under natural conditions. PREVENTING OIL SPILLS One of the best ways to protect areas from oil spills is to prevent spills from occurring in the first place. Because our society relies on petro- leum products, however, oil spills are a likely occurrence in the future ( Figure 11.10 ), especially as petroleum reserves beneath the continental shelves of the world are increasingly exploited. After the Exxon Valdez oil spill in 1989, Congress enacted the Oil Pollution Act of 1990, which defined responsibility for fiscal damage and cleanup. The act also phased out single-hulled oil tankers traveling in U.S. waters and mandated dou- ble-hulled construction by 2015. Currently, single-hulled tankers are barred from U.S. ports, and European countries, such as France and Spain, do not allow them within 320 kilometers (200 miles) of their coasts. A double hull houses two layers: An inner hull can prevent oil spillage if damage occurs to the outer hull. Studies of hull designs during groundings and collisions indicate that double-hull designs are more effective overall at reducing oil spills. However, analysis of the Exxon Valdez spill suggests that even a double-hulled tanker would not have prevented the disas- ter. Tanker designs are also being modified to limit the amount of oil spilled in the event of a hull rupture. Oil slick on surface Oil in the water column Oil in the water column Prevailing current Biodegradation by bacteria Spreading Oil droplets rise to the surface; some are biodegraded or dissolved on the way up. Methane is released to the atmosphere. Oil is photo-oxidized and evaporates. Bubbles of methane gas rise to the surface; about half dissolves in the water column. Petroleum and methane gas flow upward through faults and cracks in the sea floor. Heavy petroleum hydrocarbons sink and are deposited on the sea floor. Oil reservoir Light petroleum hydrocarbons evaporate to the atmosphere. Emulsification Mousse Dispersed surface oil can mix with water to form a frothy substance called mousse. SmartFigure 11.9 Processes acting on oil spills. When oil enters the ocean, it is acted upon by various natural processes that break up the oil. The lighter components evaporate, while the heavier components form tar balls or coat sus- pended particles and sink. The remaining dispersed oil photo-oxidizes or can mix with water, creating a frothy substance called “mousse.” https://goo.gl/8kHbgP Figure 11.10 Who is at fault? M11_TRUJ3545_12_SE_C11.indd 355 12/16/15 8:00 PM

358 CHAPTER 11 Marine Pollution food chains, these and other chemicals have been classified as persistent organic pollut- ants (POPs) capable of causing cancer, birth defects, and other grave harm. DDT was widely used in agriculture during the 1950s and improved crop pro- duction throughout developing countries for several decades. However, its extreme effectiveness as an in- secticide and persistence as a toxin in the environ- ment eventually resulted in a host of environmental problems, including devastating effects on marine food chains. In 1962, biologist Rachel Carson published her seminal book Silent Spring about the dangers of DDT and other chemicals in the environment. Her book played an important role in the environmental move- ment and DDT was subsequently banned in the United States in 1972. PCBs are industrial chemicals that were once widely used as liquid coolants and insulation in indus- trial equipment such as power transformers, where they were released into the environment. PCBs were also widely used in wiring, paints, caulks, hydraulic oils, carbonless copy paper, and a host of other products. PCBs have been shown to cause liver cancer and harmful genetic mutations in animals. PCBs can also affect animal reproduction: They have been indicated as causes of spontaneous abortions in sea lions and the death of shrimp in Escambia Bay, Florida. DDT AND EGGSHELLS Since 1972, the EPA has banned the use of DDT in the United States. Worldwide, the pesticide is banned from agricultural use, but it continues to be used in limited quantities for public health purposes. Ironically, U.S. companies continue to produce DDT and supply it to other countries. The danger of excessive use of DDT and similar pesticides first became ap- parent in the marine environment when it affected marine bird populations. During the 1960s, there was a serious decline in the brown pelican population of Anacapa Island off Southern California ( Figure 11.14 ). High concentrations of DDT in the fish eaten by the birds had caused them to produce eggs with excessively thin shells because DDT made it more difficult for calcium to be incorporated into the egg shells. The osprey is a common bird of prey in coastal waters that is similar to a large hawk. The osprey population of Long Island Sound declined in the late 1950s and 1960s because DDT contamination caused them to produce eggs with thin shells, too. Since the ban on DDT, the osprey, brown pelican, and many other species affected by the chemical are making remarkable comebacks. DDT AND PCBS LINGER IN THE ENVIRONMENT The chemicals DDT, which was banned in 1972, and PCBs, which were banned in 1977, generally enter the ocean through the atmosphere and river runoff. They are initially concentrated in the thin slick of organic chemicals at the ocean surface, and then they gradually sink to the bottom, attached to sinking particles. A study off the coast of Scotland indicated that open-ocean concentrations of DDT and PCBs are 10 and 12 times less, respec- tively, than in coastal waters. Long-term studies have shown that DDT residue in mollusks along the U.S. coasts peaked in 1968. Although most countries have banned their use, DDT and PCBs are so per- vasive in the marine environment that even Antarctic marine organisms contain measurable quantities of them. Because there has been no agriculture or industry in Antarctica to introduce them directly, these chemicals must have been transported to Antarctica from distant sources by winds and ocean currents. Figure 11.13 Boston Harbor sewage project. (a) Diagrammatic view of the Boston Harbor sewage project tunnels and (b) a map of the sewage outfall area. (a) The Boston Harbor sewage project includes tunnels that transport sewage to an outfall 15 kilometers (9.5 miles) offshore at a depth of 76 meters (250 feet) beneath the ocean floor. Massachusetts Bay Cape Cod Bay Massachusetts Bay C a p e C o d Cape Ann S t e ll w a g e n B a n k Boston tunnel Deer Island Treatment Plant tunnel 0 5 10 Kilometers 0 5 10 Miles 0–4.9 5–9.9 10–24.9 25–49.9 50–74.9 75–99.9 100 and deeper Depth (meters) N (b) Bathymetric map of the coastal ocean in the Boston-Cape Cod area, showing the proximity of the new sewage outfall ( red x ) to Stellwagen Bank, which is a National Marine Sanctuary. X Interdisciplinary Relationship Interdisciplinary Relationship M11_TRUJ3545_12_SE_C11.indd 358 12/16/15 8:00 PM

11.3 What Marine Environmental Problems Are Associated with Non-Petroleum Chemical Pollution? 361 waste disposal stream that eventually enters the oceans. Studies show that amount of caffeine in sewage effluent has been increasing over time and that this upsurge has an unknown effect on marine organisms. In addition, industrial chemicals enter the oceans via water runoff from land. Fertilizers are one example of an industrial chemical that is spread on lawns to promote growth. When these fertilizers are washed off land and make their way to coastal waters, they can cause the overabundance of algae known as a harmful algal bloom (HAB) (see Section 13.2 in Chapter 13). CONCEPT CHECK 11.3 Specify the marine environmental problems associated with non-petroleum chemical pollution. 1 How would dumping sewage in deeper water off the East Coast help reduce negative impacts on the ocean floor? 2 Discuss the animal populations that clearly suffered from the effects of DDT and the way in which this negative effect was manifested. 3 What causes Minamata disease? What are the symptoms of the disease in humans? Interdisciplinary Relationship 0 25 20 50 56 84 348 75 100 Fish consumption rate (grams/day) 10 1.0 100 10 1.0 100 400 Methylmercury concentration in fish (ppm) Change in scale Change in scale DANGER EXTREME DANGER DANGER + FDA standard = 1.0 ppm S a f e i n g e s t i o n l e v e l = 0 . 0 3 m g / d a y P O S S I B L E H A Z A R D F i r s t s i g n s o f M i n a m a t a d i s e a s e = 0 . 3 m g / d a y SAFE LEVEL Swordfish Contaminated fish from Minamata Bay Tuna Average fish consumption in U.S. Average fish consumption in Sweden Average fish consumption in Japan Average fish consumption in Minamata Consuming even low amounts of highly contaminated fish can result in mercury poisoning. At the time of mercury poisoning in Minamata Bay, the high levels of mercury in fish, combined with the residents' high consumption of fish, resulted in extreme danger of mercury poisoning. Note that higher levels of fish consumption increase exposure to mercury poisoning. Based on the average U.S. consumption rate, tuna and swordfish are deemed safe to consume because the mercury content is within the FDA safe ingestion level. RECAP Many other types of pollution besides petroleum are considered marine chemical pollutants, including sewage sludge, DDTs, PCBs, mercury, and chemicals contained in prescription and non-prescription drugs. SmartFigure 11.17 Methylmercury concentration in fish, fish consumption rates for various populations, and the danger levels of mercury poisoning. Graph showing the relative risk of contracting Minamata disease based on the amount of fish consumed and the concentra- tion of toxic methylmercury in fish for people in the United States, Sweden, and Japan—including Minamata. The graph shows that a high consumption rate of fish containing high concentrations of mercury results in extreme danger of mercury poisoning ( upper right ) and that tuna and most swordfish are safe to consume at average U.S. consumption rates ( lower left ). Although a typical serving portion of fish is about 170 grams (6 ounces), the graph shows that the average U.S. fish consumption rate is 17 grams (0.6 ounce) per day. https://goo.gl/YspqKE STUDENTS SOMETIMES ASK . . . How has the radioactivity that leaked from Japan’s Fukushima power plant affected marine fish? For example, is it safe to eat fish from the ocean? T he failure of the cooling system in Japan’s Fuku- shima Dai-ichi nuclear power plant as a result of the destructive 2011 tsunami caused explosions and the release of radioactive substances into the atmo- sphere, groundwater, and ocean surrounding the plant. Even though the ocean is large and has good mixing mechanisms that serve to dilute the radioac- tivity, radioactive cesium and iodine from Fukushima have been transported by ocean surface currents and subsequently detected in waters along North America’s West Coast. However, the radioactivity is present in such tiny amounts that the levels are not deemed a human health hazard. Overall, a much greater human-exposure radiation issue remains for the people who live and work in the contaminated area on land in Japan. In the ocean, marine organisms in the vicinity of Fukushima received some of the highest doses of radioactive materials, and so commercial fishing is closed in those regions. However, large ocean-going fish that eat contaminated organisms can biomagnify the radioactive materials and carry those substances throughout the oceans. For example, bluefin tuna that migrate between the waters off San Diego, California, and near Japan have been found to carry tiny amounts of Fukushima cesium. Even so, these fish are deemed safe to eat. Marine chemists who study probability statistics suggest that a person who eats five times the amount of fish that an aver- age American does—and eats only contaminated fish for a year—would end up with a radiation dose that would cause an extra two cancers in 10 million people. So the risk to human health by eating con- taminated fish is extremely small. In fact, the risk is hundreds of times less than that posed by the inges- tion of polonium-210, a naturally occurring radioac- tive element present in small amounts in seafood, although most people aren’t concerned about it. M11_TRUJ3545_12_SE_C11.indd 361 01/06/16 7:18 AM

364 CHAPTER 11 Marine Pollution PLASTIC NURDLES IN THE MARINE ENVIRONMENT Today, nearly all plastic prod- ucts are produced from small pre-production plastic pellets called nurdles that range in size from a BB to a pea ( Figure 11.24 ). Nurdles are transported in bulk aboard commercial vessels and are found throughout the oceans, probably due to spillage at loading terminals. Because of ocean surface currents that wash plastics ashore, plastic nurdles and other trash can be found on most beaches—even in remote areas. In one of the best-documented studies of trash on beaches, for example, researchers pains- takingly counted all debris larger than a pinhead along selected transits in Orange County, California. Based on what was collected during the six-week sampling period, researchers project that each year Orange County beaches receive an as- tonishing 106.9 million pieces of debris, 98% (105.2 million) of which are nurdles. Other studies have shown that some Bermuda beaches contain up to 10,000 nur- dles per square meter (925 nurdles per square foot) and some beaches on Martha’s Vineyard in Massachusetts contain 16,000 nurdles per square meter (1480 nurdles per square foot). Figure 11.22 Examples of how floating plastic trash endangers marine life. (a) A female northern elephant seal ( Mirounga angustirostris ) with a plastic packing strap tight around her neck. (b) A herring gull ( Larus argentatus ) entangled in a plastic six-pack ring. (c) Photo of a young laysan albatross ( Phoebastria immutabilis ) from Midway Island at the northwestern end of the Hawaiian chain that died from a stomach full of pieces of floating plastic trash ( right ) including lighters, bottle caps, electrical connectors, and other materials unintentionally fed to it by its parents. Web Video Plastic Pollution: Our Synthetic Sea https://goo.gl/EAoRPF STUDENTS SOMETIMES ASK . . . All this pollution is distressing. Is there anything I can do about it? Y es, there are many things you can do to help protect the ocean, some of which are listed in this book’s Afterword. They all involve making intelligent choices and minimizing your impact on the environment. Non-point source pollution, for example, is something that the general public is directly responsible for, so one of the best methods of prevention may be educating people. Once people understand the impact their choices have on the environment, they often realize that the solution is up to all of us. M11_TRUJ3545_12_SE_C11.indd 364 12/16/15 8:00 PM

11.5 What Marine Environmental Problems Are Associated with Biological Pollution? 367 STUDENTS SOMETIMES ASK . . . What does the garbage patch look like? Can it be seen from space? How can it be cleaned up? O ne of the problems with determining the size of the gar- bage patch is that it lacks definitive edges, and so there are no accurate estimates of its size. Contrary to what many people have heard about it, the patch is not a floating island of garbage. Since most of the plastic pieces are about the size of a fingernail or smaller, the garbage patch cannot easily be seen from a boat, let alone from space. In fact, oceanog- raphers use fine mesh trawl nets to determine its existence. A better way to visualize the garbage patch is to imagine a very thin brothy soup with some tiny scattered pieces of plastic. Removing the floating garbage is not as easy as it sounds. For one thing, the trash is unevenly distributed. For another, it involves gathering small pieces that are spread across a huge area, which would require an armada of ships working continuously for many years to collect all the trash. Even if large amounts of floating trash were collected, what would be done with all of it once back on shore, especially the parts that can’t be recycled? Certainly a bigger issue is that skimming the ocean’s surface waters for floating trash would also remove plankton that are crucial to marine food webs. At the moment, the best approach appears to be preventing the trash from getting to the ocean in the first place. CONCEPT CHECK 11.4 Specify the marine environmental problems associated with non-point source pollution, including trash. 1 What is non-point source pollution, and how does it get to the ocean? What other ways does trash get into the ocean? 2 What properties contributed to plastics being considered a miracle substance? How do those same prop- erties cause them to be unusually per- sistent and damaging in the marine environment? 11.5 What Marine Environmental Problems Are Associated with Biological Pollution? As human activities increase around the globe, so does the transportation of biologi- cal pollutants, otherwise known as non-native species . Non-native species (also called exotic , alien , or invasive species ) are species that originate in a particular area but are introduced into new environments either by the deliberate or accidental ac- tions of humans and so are classified as biological pollutants. Because non-native species inhabit new areas where they may lack predators or other natural controls, they can wreak ecological havoc by outcompeting and dominating native popula- tions. Non-native species can also introduce new parasites and/or diseases. In some cases, non-native species completely transform ecosystems. In the United States alone, more than 7000 introduced species (not counting microorganisms) have been documented, of which about 15% cause ecological and economic damage. In fact, invasive species cause an estimated $137 billion in loss and damages in the United States each year. Let’s examine a few examples of non-native marine species that are causing problems worldwide. The Seaweed Caulerpa taxifolia The seaweed Caulerpa taxifolia , which is native in tropical waters, is one example of an invasive, non-native marine species. It is ideal as a decorative alga in salt- water aquariums because it is hardy, fast growing, and not edible by most fish. However, when it is introduced into suitable new habitats (most likely as a result of the dumping of household saltwater aquariums), it becomes a dominant and persis- tent species that displaces native seaweeds and other marine life. In 1984, a cold- tolerant clone of Caulerpa taxifolia produced for the aquarium industry was first introduced into the Mediterranean Sea, where it has overwhelmed aquatic ecosys- tems and continues to spread. In 2000, this clone was also found along the coast of New South Wales, Australia, and in two Southern California lagoons. The Caulerpa taxifolia outbreak in one of these lagoons, Aqua Hedionda Lagoon in Carlsbad, Cal- ifornia, was most probably caused by an aquarium owner who improperly dumped the seaweed into a storm drain, which allowed it to enter the lagoon where the invasion was discovered. California has since passed a law forbidding the posses- sion, sale, or transport of Caulerpa taxifolia within the state. A public awareness campaign was initiated that was successful in stopping the spread of this non-native species ( Figure 11.27 ). The distribution of Caulerpa in Aqua Hedionda Lagoon was small enough to be considered controllable, so divers covered patches of the seaweed with large tarps held down with sandbags at the edges of the infestation. Then chlorine was injected below the tarp, killing all living organisms inside. Eradication efforts in Southern California appear to have been successful. However, because Caulerpa taxifolia can regenerate from very small fragments, repeated surveys are being conducted in these lagoons to eliminate all remaining occurrences of the seaweed. M11_TRUJ3545_12_SE_C11.indd 367 12/16/15 8:01 PM

368 CHAPTER 11 Marine Pollution Zebra Mussels Another example of a non-native aquatic species is the Euro- pean zebra mussel ( Dreissena polymorpha ), which was first discovered in the Great Lakes region in 1988. Zebra mus- sels probably entered North America in the ballast water 7 of a freighter from Europe and have since proliferated rapidly in waters of eastern Canada and the United States. In doing so, they’ve driven out native mussels, altered the ecology of fresh- water lakes and streams, and blocked the water-carrying pipes of power plants and many other industrial facilities. Although zebra mussels are exceedingly hardy organisms, researchers are working to identify predators, parasites, and infectious mi- crobes that can kill zebra mussels but leave native populations unharmed. Other Notable Examples of Marine Biological Pollution Other notable examples of harmful non-native aquatic species include the Atlantic comb jelly Mnemiopsis leidyi , which was transported in ballast water to the Black Sea and has done ex- tensive damage to the region’s fishing and tourist industries; the Atlantic cordgrass Spartina alterniflora , which has invaded soft-bottom coasts of California, Washington, and China; the water hyacinth Eichhornia crassipes , which infests tropical es- tuaries and other water bodies; and the European green crab Carcinus maenas , which has invaded the Pacific Coast and is altering coastal food webs. Figure 11.27 Invasion of Caulerpa taxifolia. The seaweed Caulerpa taxifolia is thought to have been illegally dumped by an aquarium owner into a storm drain that allowed the seaweed to spread into Southern California coastal lagoons. The alga was eradiated because of good public awareness and quick action by local authorities. 7 Ballast water is taken into the hold of a ship to enhance stability and then released in a port when it is no longer needed. RECAP Worldwide, there is a growing concern about the introduction of non-native species, which are organisms that are trans- ported to regions where they have no natural predators and so their populations explode and crowd out other species that normally live there. CONCEPT CHECK 11.5 Specify the environmental problems associated with biological pollution. 1 What are non-native species? Why can they be so damaging to ecosystems? 2 How did the invasive species Caulerpa taxifolia and zebra mussels get released into new environments? 11.6 What Laws Govern Ocean Ownership? Who owns the ocean? Who owns the sea floor? If a company wanted to drill for oil offshore between two different countries, would it have to obtain permission from ei- ther country? The current extraction of minerals and petroleum on the coastal sea floor necessitates laws that unambiguously answer these questions. Exploration and develop- ment of marine resources is also occurring further offshore, far from the jurisdiction of any country. Furthermore, overfishing and pollution are worsening. Are these kinds of problems covered by long-established laws? The answer is yes . . . and no. Mare Liberum and the Territorial Sea In 1609, Hugo Grotius, a Dutch jurist and scholar whose writings eventually helped formulate international law, urged freedom of the seas to all nations in his treatise Mare Liberum ( mare = sea, liberum = free), which was premised on the assumption that the sea’s major known resource—fish—exists in inexhaustible supply. Never- theless, controversy continued over whether nations could control a portion of an ocean, such as the ocean adjacent to a nation’s coastline. M11_TRUJ3545_12_SE_C11.indd 368 12/16/15 8:01 PM

11.6 What Laws Govern Ocean Ownership? 369 Dutch jurist Cornelius van Bynkershoek attempted to solve this problem in De Dominio Maris ( de = of, dominio = domain, maris = sea), published in 1702. It pro- vided for national domain over the sea out to the distance that could be protected by cannons from the shore ( Figure 11.28 ), an area called the territorial sea . Just how far from shore did the territorial sea extend? The British had determined in 1672 that cannon range extended 1 league (3 nautical miles) from shore. Thus, every country with a coastline maintained ownership over a 3-mile territorial limit from shore. Law of the Sea In response to new technology that facilitated mining the ocean floor, the first United Nations Conference on the Law of the Sea , held in 1958 in Geneva, Switzerland, established that prospecting and mining of minerals on the continental shelf was under the control of the country that owned the nearest land. Because the continental shelf is the portion of the sea floor extending from the coastline to where the slope markedly increases, the seaward limit of the shelf is subject to in- terpretation. Unfortunately, the continental shelf was not well defined in the treaty, which led to disputes. In 1960, the second United Nations Conference on the Law of the Sea was also held in Geneva, but it made little progress toward an unambigu- ous and fair treaty concerning ownership of the coastal ocean. Meetings of the third Law of the Sea Conference were held during 1973–1982. A new Law of the Sea treaty was adopted by a vote of 130 to 4, with 17 abstentions. Most developing nations that could benefit significantly from the treaty voted to adopt it. The United States, Turkey, Israel, and Venezuela opposed the new treaty because of concerns that it made sea floor mining unprofitable. The abstaining countries included the Soviet Union, Great Britain, Belgium, the Netherlands, Italy, and West Germany, all of which were interested in sea floor mining, too. Nevertheless, the treaty was rati- fied by the required 60th nation in 1993, establishing it as international law. Meanwhile, in the early 1990s, the United States and other nations negotiated an agreement to the Law of the Sea that fundamentally overhauled the deep sea floor mining provisions of the 1982 convention. The agreement, adopted in 1994, modified the convention to include the following provisions: (1) Eliminate produc- tion controls on sea floor mining, (2) scale back the structure of the organization that administers deep seabed mining, (3) ensure that the United States has a per- manent seat and political say on any amendment to deep sea floor mining provi- sions, (4) eliminate the objectionable provisions on mandatory technology transfer, and (5) provide assured access for any future qualified miners. Even with the suc- cessful negotiation of these provisions, the United States did not ratify the modified treaty because of lingering concerns about seabed mining. Despite the fact that 162 coastal nations—including all the countries in the European Community—have ratified the treaty and have made it the definitive word on coastal law, the United States has still not officially ratified the Law of the Sea treaty. Moreover, this means that the United States doesn’t have the legal right to extend its maritime claims or hold a seat on the commission that reviews the plans of seabed mining. The United States has shown mixed interest in ratifying the Law of the Sea treaty. In 2004 and 2007, for example, U.S. Senate committees voted for ratifying the treaty, only to have a vote by the full Senate blocked both times by senators who were concerned about U.S. access to the seabed, potential loss of U.S. sovereignty, and other factors. International respect for the treaty is also mixed. In 2007, for example, a Russian expedition used two submersibles to descend 4300 meters (2.7 miles) below Arctic ice to collect samples and plant a Russian flag on the Arctic seabed, symbolically staking its claim of ownership of the sea floor and surrounding waters near the North Pole ( Figure 11.29 ). In 2012, the U.S. Senate re-examined joining the Law of the Sea Convention and made it a top priority for the United States, stating that the convention sets forth a comprehensive legal framework governing uses of the oceans and protects and ad- vances a broad range of U.S. interests, including U.S. national security and economic interests. In fact, current and past presidential administrations (both Republican Figure 11.28 Territorial sea. The territorial sea, which extends 3 nautical miles from the nearest shore, was originally determined by the reach of cannons fired from land. Cannons shown are in Korcula, Croatia. Figure 11.29 A Russian submersible plants its flag on the Arctic Ocean seabed. In 2007, a Russian expedition planted the Russian flag on the ocean floor near the North Pole to symbolically claim ownership of the Arctic sea floor and its waters. M11_TRUJ3545_12_SE_C11.indd 369 12/16/15 8:01 PM

370 CHAPTER 11 Marine Pollution and Democratic, which demonstrates broad bipartisan support), the U.S. military, and relevant industry and other groups all strongly support joining the conven- tion. Experts agree that only by joining the convention can the United States maximize legal certainty and have a defined path to securing international recogni- tion of its continental shelf. The Law of the Sea treaty specifies how coastal na- tions watch over their natural resources, settle maritime boundary disputes, and—especially in the Arctic— extend their rights to any riches on or beneath the adjacent sea floor. The four main components of the treaty are: 1. Coastal nations jurisdiction. The treaty estab- lished a uniform 19-kilometer (12-mile) territo- rial sea and a 370-kilometer (200-nautical-mile) exclusive economic zone (EEZ) from all land (including islands) within a nation. Each of the 151 coastal nations has jurisdiction over min- eral resources, fishing, and pollution regulation within its EEZ. If the continental shelf (defined geologically) exceeds the 370-kilometer EEZ, the EEZ is extended to 648 kilometers (350 nautical miles) from shore. Although the United States is not yet a party to the treaty, it is actively explor- ing and mapping its extended continental shelf. 2. Ship passage. The right of free passage for all vessels on the high seas is preserved. The right of free passage is also provided within territorial seas and through straits used for international navigation. 3. Deep-ocean mineral resources. Private exploitation of sea floor resources may proceed under the regulation of the International Seabed Authority (ISA), within which a mining company will be strictly controlled by the United Nations. This provision required mining companies to fund two mining operations—their own and one operated by the regulatory United Nations. As discussed above, some industrialized nations still oppose this portion of the law even though it was modified by an agreement to the convention in 1994 that eliminated some of the restrictive regulatory components. The ISA also grants 15-year exploration rights for countries to mine sea floor mineral resources. 4. Arbitration of disputes. A United Nations Law of the Sea tribunal will arbi- trate any disputes in the treaty or disputes concerning ownership rights. The Law of the Sea treaty puts 42% of the world’s oceans under the control of coastal nations. The EEZ of the United States consists of about 11.5 million square kilometers (4.2 million square miles) ( Figure 11.30 ), which is about 30% more than the entire land area of the United States and its territories. This huge offshore area is widely believed to have tremendous economic potential. RECAP Ownership of the ocean and sea floor is regulated by the inter- nationally ratified Law of the Sea treaty, which gives nations control of waters and the sea floor immediately adjacent to their coasts. Figure 11.30 The U.S. exclusive economic zone (EEZ). Map showing the U.S. exclusive eco- nomic zone (EEZ), which extends from shore to a distance of 370 kilometers (200 nautical miles) from the continent or islands. If the continental shelf (defined geologically) exceeds the 370-kilo- meter EEZ, the EEZ is extended to 648 kilometers (350 nautical miles) from shore. ARCTIC OCEAN NORTH PACIFIC OCEAN Bering Sea SOUTH PACIFIC OCEAN 140°E 140°W 120°E 120°W 100°W 80°W 60°W 0° 20°S 40°N 60°N 80°N 40°S 160°E 160°W 180° Tropic of Cancer Arctic Circle Tropic of Capricorn Equator Wake Island Guam Midway Islands Northern Mariana Islands Johnston Atoll Kingman Reef and Palmyra Atoll Jarvis Island Puerto Rico and U.S. Virgin Islands Navassa Island Howland and Baker Islands American Samoa Hawaiian Islands A l e u t i a n I s l a n d s UNITED STATES 0 1,500 3,000 Kilometers 0 1,500 3,000 Miles North CONCEPT CHECK 11.6 Demonstrate an understanding of the laws that govern ocean ownership. 1 What was the basis for establishing the 3-mile territorial limit of owner- ship from shore? 2 Create a timeline outlining the development of the Law of the Sea treaty. What major country has not yet adopted the treaty? 3 Describe the four main compo- nents of the Law of the Sea treaty. M11_TRUJ3545_12_SE_C11.indd 370 12/16/15 8:01 PM

Essential Concepts Review 371 ESSENTIAL CONCEPTS REVIEW ▸ Although marine pollution seems easily defined, an all-encompassing definition is quite detailed . It is often difficult to establish the degree to which pollution affects ocean areas. The most widely used technique for determining the effects of pollu- tion is the environmental bioassay , which determines the concentration of a pollutant that causes a 50% mortality rate among test organisms. The debate continues about whether society’s wastes should be dumped in the ocean. Study Resources MasteringOceanography Study Area Quizzes Critical Thinking Question Why do some experts believe that the ocean can be a repository for many of society’s wastes? If we do use the ocean as a disposal site, what conditions should be required? Active Learning Exercise Working with another student in class, determine five common characteristics of pollu- tion. Then write down as many different types of marine pollution as you can in two minutes. Share your answers with the class. 11.1 What is pollution? ▸ Oil is a complex mixture of hydrocarbons and other substances , most of which are naturally biodegradable . Thus, many marine pollution experts consider oil to be among the least damaging of all substances introduced into the marine environment. In areas that have experi- enced oil spills, recovery can be as rapid as a few years . Still, oil spills can cover large areas and kill many animals . After the much- publicized Exxon Valdez oil spill in Alaska, many novel approaches were used to clean the spilled oil , including releasing oil-eating bacte- ria ( bioremediation ). Study Resources MasteringOceanography Study Area Quizzes, MasteringOceanography Web Table 11.1 Critical Thinking Question Specify the marine environmental problems associated with petroleum pollution. Active Learning Exercise Working with another student in class and using the blue circles shown in Figure 11.3, calculate the total amount of oil that has been spilled into the oceans since the 1991 Persian Gulf War from “natural seeps and regular human activities such as transportation.” Using the circles in Figure 11.3 for scale, sketch circles that represent the amounts in both U.S. waters and globally. Compare these values to the other circles shown in Figure 11.3 and share your results with the class. 11.2 What marine environmental problems are associated with petroleum pollution? Natural seeps 47% Petroleum consumption 72% Petroleum extraction 6% All sources Human sources Petroleum transportation 22% Human sources 53% Human sources account for only about half of all oil entering the oceans. M11_TRUJ3545_12_SE_C11.indd 371 12/16/15 8:01 PM

372 CHAPTER 11 Marine Pollution 11.3 What marine environmental problems are associated with non-petroleum chemical pollution? ▸ Millions of tons of sewage sludge have been dumped offshore in coastal waters. Although 1972 legislation required an end to dumping of sewage in the coastal ocean by 1981, exceptions continue to be made . Increased public concern resulted in new legislation to prohibit sewage dumping in the ocean. ▸ DDT and PCBs are persistent, biologically hazardous chemicals that have been introduced into the ocean by human activities. DDT pollution produced a decline in the Long Island osprey population in the 1950s and the brown pelican population of the California coast in the 1960s. Virtual cessation of DDT use in the Northern Hemisphere in 1972 allowed the recovery of both populations . The DDT thinned the eggshells and reduced the number of successful hatchings. PCBs have been implicated in causing health problems in sea lions and shrimp. ▸ Mercury poisoning was the first major human disaster resulting from ocean pollution. It is now called Minamata disease , after the bay in Japan where it first occurred in 1953. The toxic form of mercury is methylmercury, which bioaccumulates in the tissues of many large fish , most notably tuna and swordfish, and works its way up the food web in a process called bio- magnification . To prevent mercury poisonings in the United States, stringent methylmercury contamination levels in fish have been established by the FDA. Study Resources MasteringOceanography Study Area Quizzes Critical Thinking Question Specify the marine environmental problems associated with non-petroleum chemical pollution. Active Learning Exercise Working with another student in class, discuss what we should do with sewage sludge if we can’t dump it into the ocean. What are the most feasible options? ▸ Non-point source pollution includes road oil and trash. Plastics have gained popularity in modern culture because they are lightweight, strong, durable, and inexpensive. Unfortunately, these same properties make them a relentless source of floating trash in the ocean, especially because they break down into progressively smaller pieces over time. The amount of plastics accumulating in the oceans has increased dramatically. Certain types of plastics are known to be lethal to marine mammals, birds, and turtles . International legislation such as MARPOL regulates the disposal of trash in the ocean but lacks enforcement. Study Resources MasteringOceanography Study Area Quizzes, Web Videos Critical Thinking Question List and describe the three main problems that floating plastic trash presents to marine organ- isms. Of the three, which one is potentially the most serious threat? Explain. Active Learning Exercise Working with another student in class, describe the two main sources of microplastics and discuss problems that microplastics create in the oceans. 11.4 What marine environmental problems are associated with non-point source pollution, including trash? DDT concentration (parts per million) 25 ppm 2 ppm 0.5 ppm 0.04 ppm 0.000003 ppm Water Zooplankton Small fish Large fish Osprey Biomagnification causes toxins to be passed through marine food chains and accumulate in the tissues of larger organisms.

Essential Concepts Review 373 ▸ Coastal waters support about 95% of the total mass of life in the oceans , and they are important areas for commerce, recreation, fisheries, and the disposal of waste. Coastal law is specified in the United Nations Convention on the Law of the Sea , which has been ratified by 153 coastal nations and in force since 1994. The treaty delineates national obligations, rights, and jurisdiction in coastal waters . In spite of its near-universal acceptance, the United States has still not ratified the treaty . Study Resources MasteringOceanography Study Area Quizzes Critical Thinking Question Discuss reasons less-developed nations believe that the open ocean is the com- mon heritage of all, whereas the more-developed nations believe that the open ocean’s resources belong to those who recover them. Active Learning Exercise Working with another student in class, have each student take one of two sides: (1) only counties with coastlines should have rights to ocean resources, or (2) landlocked countries deserve the same rights to ocean resources as do nations with coastlines. Have each student present their side to each other and then share their views of the topic with the entire class to reach a consensus. 11.6 What laws govern ocean ownership? ARCTIC OCEAN NORTH PACIFIC OCEAN Bering Sea SOUTH PACIFIC OCEAN 140°E 140°W 120°E 120°W 100°W 80°W 60°W 0° 20°S 40°N 60°N 80°N 40°S 160°E 160°W 180° Tropic of Cancer Arctic Circle Tropic of Capricorn Equator Wake Island Guam Midway Islands Northern Mariana Islands Johnston Atoll Kingman Reef and Palmyra Atoll Jarvis Island Puerto Rico and U.S. Virgin Islands Navassa Island Howland and Baker Islands American Samoa Hawaiian Islands A l e u t i a n Is l a n d s UNITED STATES 0 1,500 3,000 Kilometers 0 1,500 3,000 Miles North www.masteringoceanography.com Looking for additional review and test prep materials? With individualized coaching on the toughest topics of the course, MasteringOceanography offers a wide variety of ways for you to move beyond memorization and deeply grasp the underlying processes of how the oceans work. Visit the Study Area in www.masteringoceanography.com to find practice quizzes, study tools, and multimedia that will improve your understanding of this chapter’s content. Sign in today to enjoy the following features: Self Study Quizzes, SmartFigures, SmartTables, Oceanography Videos, Squidtoons, Geoscience Animation Library, RSS Feeds, Digital Study Modules, and an optional Pearson eText. ▸ The introduction of biological pollution such as non-native spe- cies (such as Caulerpa taxifolia and zebra mussels) into new envi- ronments can cause severe ecological and economic damage. Study Resources MasteringOceanography Study Area Quizzes Critical Thinking Question Specify the marine environmental problems associated with biologi- cal pollution. Active Learning Exercise Working with another student in class, search the Internet to find information about the import of the non-native cane toad ( Rhinella marina ) in Australia. Why were the toads brought in from Hawaii? What is the issue that remains today? 11.5 What marine environmental problems are associated with biological pollution? M11_TRUJ3545_12_SE_C11.indd 373 12/16/15 8:01 PM