When the world’s greatest marine scientists get together at international conferences, their primary topic of discussion, especially for the last five or so years, has been human actions that trigger and accelerate the decline of ocean habitats and species. During their April 2011 meeting at the University of Oxford, the scientists took these concerns about ocean health to a new level.
During this event organized by the International Programme on the State of the Ocean and the International Union for Conservation of Nature, these dozens of world science leaders came to conclusions that should be of concern to every human on the planet, but especially to people who continue to mindlessly eat fish and other ocean life. The scientists warn that we are experiencing severe declines in many species, to the point of commercial extinction, along with unparalleled rates of regional extinctions of habitat types. They say that we face losing—within a single generation—both marine species and the marine ecosystems on which they depend for survival.1
“If the various estimates we have received come true,” remarked United Nations environmental official Pavan Sukhdev, “then we are in a situation where forty years down the line we, effectively, are out of fish.” UN experts estimate that 30 percent of the world’s fish stocks have already collapsed, and current trends project that virtually all of the fisheries in all of the oceans will be devoid of commercially viable catches by 2050.2
It’s like a perfect ecological storm. As overfishing continues and humans eat some species to extinction, we see the combined effects of climate change, human-caused pollution, and habitat loss begin to produce a global extinction event in the ocean. What is happening in our oceans today is comparable to what happened when the dinosaurs and many other life-forms were extinguished. Scientists have documented that at least five global extinction events have occurred over the past 600 million years, and this latest one could rival them all.3
During the 2011 conference, the marine scientists uncovered several of the vital reasons sea life has reached this crisis. The following summarizes their major findings.4
Climate change. Habitat loss and overfishing are the primary causes of marine species extinction, but climate change is now playing a role in accelerating that process. Warmer water in the oceans forces some species into deeper, cooler waters, where they are unable to survive. Simultaneously, shifts in ocean currents, along with warmer temperatures caused by climate change, disrupt the food supplies of marine animals, further stressing the ability of entire species to adapt and survive in the altered climate.
Human activities. The extensive ecosystem damage caused by human actions is compromising the ocean’s natural ability to adapt to climate change. Up to a certain point, the oceans display resilience when stressed by climate change, but human-caused disruptions have undermined that natural capacity to adapt. For instance, the combination of agricultural runoff and other pollutants, such as pathogens and endocrine-disrupting chemicals, has reduced the coral reefs’ ability to recover. As a result, reef ecosystems are no longer dominated by coral but are dominated by algae, which hastens the loss of genetic diversity among fish and other ocean life.
Oxygen loss. Warming and acidification of the oceans, caused primarily by human actions, have accelerated the process of hypoxia. Hypoxia, which is detrimental to aerobic organisms, occurs when the amount of dissolved oxygen in a body of water is reduced. It doesn’t take long before this oxygen deprivation sets in motion a chain reaction of die-off events, starting with microorganisms and then extending up the food chain.
Global outcomes. Many predicted worst-case scenarios about the ocean have already come to pass. There is a decrease in Arctic Sea ice, the Greenland ice sheet and the Antarctic ice sheets are melting, the sea level is rising, and more methane is being released from the world’s sea beds. Such effects are compounding other problems, including the appearance of harmful algal blooms; the loss of large, long-lived fish species; and the overall destabilization of food webs in marine ecosystems.
When we consider the effects of human activities on ocean life, we often forget the deepest waters, which are found at two hundred meters and below. This is the largest environment on the planet, making up about half of the Earth’s surface, and for centuries it has been a dump site.
As part of an initiative called Census of Marine Life, marine scientists from numerous countries analyzed everything that humans now know about the deep-sea environment and the effects of human activities. The massive study results were released in August 2011.5 The following findings about the deep seafloor—and the estimated 10 million species that live there—deserve to be factored into the discussion about whether it is justifiable to consume aquatic life.
Litter and waste. The routine dumping of certain types of waste from ships was banned by an international agreement in 1972. The practice persists, however, and an estimated 6.4 million tons of litter and waste from bulk carriers, tankers, fishing boats, and other sources are still dumped into deep seas annually. Almost all scientific surveys of the seafloor, which are done using remotely operated vehicles, detect waste products. The most common are plastics, aluminum cans, glass, metal, and fishing gear. “The impacts of litter on deep-sea habitats and fauna,” reported the science team, “may include suffocation of animals from plastics, release of toxic chemicals, propagation of invasive species, [and] physical damage to sessile fauna such as cold-water corals from discarded trash.”6
Sewage, dredge, and mining waste. One examined site, the deep water along the eastern US seaboard, is a dump for industrial and municipal waste such as raw sewage—an estimated 36 million tons of it. The waste contains high levels of persistent organic pollutants that produce “clear faunal changes at the seabed.”7 There has yet to be an adequate measure of contamination in the sea life that feeds on this fauna. Toxic mining waste is most commonly found in deep-sea areas near places like Papua New Guinea.
Pharmaceuticals. Until the 1980s, the island of Puerto Rico gave tax incentives to pharmaceutical companies that encouraged them to dump their waste materials into deep seas about forty miles north of the island. At least 387,000 tons of drug waste, which is equivalent to about 880 Boeing 747 airliners filled with toxins, were deposited in that area. “Studies of the region used for waste disposal found demonstrable changes in the marine microbial community,” the science team wrote, “and these wastes were acutely toxic to many marine invertebrates.”8
This sort of drug waste dumping has been occurring all over the planet. Antibiotics, antidepressants, birth control pills, cancer treatments, painkillers, and a host of other pharmaceutical waste materials are known to bioaccumulate up the food chain. In addition to the intentional dumping of expired medicines, drug residues enter the oceans as a result of human excretions into sewage systems.
Radioactive waste. Residue from weapons testing and even radioactive medical waste has been concentrated on the slope and canyons of the northeastern Atlantic Ocean, and smaller disposals have occurred in the northwestern Atlantic and the northeastern and northwestern Pacific Oceans. Most of this waste was stored in drums and tipped over the side of ships. Another source of high-level radioactive waste is sunken nuclear submarines, which represent a significant threat to the environment.
Industrial chemicals. The most commonly detected industrial toxins are persistent organic pollutants, such as dioxins, toxic metals, pesticides, herbicides, and plastics that are resistant to degradation and accumulate in deep-sea sediments. Contaminant levels in fish have only recently been measured. Initial findings show the presence of dioxins in red shrimp (Aristeus antennatus) in the western Mediterranean and in fish at depths of 900 to 1,500 meters in the northwestern Mediterranean. Bioaccumulation of polycyclic aromatic hydrocarbons in aquatic life is also being recorded in the deep Gulf of Mexico.
Pollution decay from lost ships. Many thousands of ships have sunk over just the past century, and no one has a complete count to adequately assess the possible contamination issues. In World War II alone, during the battle of the Atlantic between the United States, Britain, and Germany, nearly four thousand military and merchant ships sank, often in the deepest waters. Many of these ships carried munitions that now provide a persistent source of toxic pollution and threatens ecosystems and aquatic life. Further endangering these life-forms are the chemical warfare agents that the navies of various countries intentionally dumped in every ocean during the twentieth century.
Deep-sea mining and oil and gas exploration. Mining operations target manganese nodules, which grow on the deep seafloor over the course of millions of years. When these nodules are removed, local fauna becomes extinct. Other creatures are buried under layers of mining waste sediment, resulting in the extinction of even more life. “Large-scale mining activities have real potential to yield species extinction,” reported the scientists.9 Other mining targets include cobalt and polymetallic sulphides, which are built up by hydrothermal activity on the seafloor, mostly in the Pacific Ocean.
Oil and gas drilling now commonly occur at up to 3,000 meters of ocean depth. At such depths, the effects of accidents and incidental pollution are magnified. We need look no further than the April 2010 explosion at the Deepwater Horizon well in the Gulf of Mexico to see what happens when five million barrels of crude oil are released into the water. The environmental damage caused by that incident is still being seen and felt, and not just on beaches or surface waters. As reported in the November 5, 2010, National Geographic News, researchers have found colonies of coral covered with oil at 1,400 meters of depth, and this pollution has resulted in the corals’ progressive death and the consequential extinction of aquatic life that depended on the coral.10
The studies and reports mentioned above were done at the macro level, and these findings are reinforced by information coming from observers at the micro level. For instance, consider what has been called “the great lobster die-off” in Long Island Sound, where nine-tenths of the lobster population disappeared over the past decade or so.
On August 8, 2011, the New York Times reported that the lobster has fallen victim to human actions: “Scientists blamed global warming, citing increased temperatures in the lower waters where lobsters live. Other culprits were pesticides like those deployed against the West Nile virus. The die-off began around the same time that the remnants of Hurricane Floyd swept over Long Island and, lobstermen believe, flushed pesticides into the Sound.”11
Overfishing and the acidification of oceans (caused by rising concentrations of carbon dioxide in the atmosphere) create ideal conditions for explosions in the population of jellyfish. On July 8, 2011, a columnist for the Guardian, a British newspaper, reported that jellyfish had replaced mackerel as the predominant species in Cardigan Bay in west Wales. “Until 2010, mackerel were the one reliable catch in Cardigan Bay,” wrote George Monbiot. “Last year it all changed. . . . Jellyfish. Unimaginable numbers of them. Not the transparent cocktail umbrellas I was used to, but solid, white rubbery creatures the size of footballs. They roiled in the surface or loomed, vast and pale, in the depths. There was scarcely a cubic meter of water without one.”12
The week before Monbiot wrote his column, a monstrous swarm of jellyfish shut down both reactors at the Torness Nuclear Power Station in Scotland by clogging up the water-intake system. A few days later, another jellyfish swarm closed a nuclear power plant in Israel. Similar reports of jellyfish taking over otherwise empty ocean space have come in from all over the planet.13
Ocean acidification affects fish in yet another way that humans could have never predicted. On July 2, 2011, Science News reported that acidic water makes fish ear bones less dense, rendering some species of fish oblivious to alarming sounds. Because they are unable to distinguish the sounds of predators approaching, they become easier prey.
“Since the beginning of the Industrial Revolution,” noted the article, “roughly 142 billion tons of human-made carbon dioxide has dissolved into the world’s oceans. Adding the gas to seawater creates carbonic acid and is nudging water closer to the acidic end of the pH scale at the fastest pace in 650,000 years.”14
Finally, consider what the warming and acidification of the ocean’s waters is doing to fish migratory patterns. Since 2009, according to the Telegraph, a British newspaper, a fish that causes hallucinations when eaten has started to migrate into British waters from the Mediterranean and from off the coast of South Africa. It’s a species of bream called Sarpa salpa, a plankton eater with golden stripes that poisons its predators with a hallucinogenic chemical. Humans who consume the fish can have vivid hallucinations that last for days. The newspaper recounted an incident involving two men in France (ages forty and ninety) who were hospitalized after eating Sarpa salpa. Within minutes after the meal, they experienced auditory hallucinations and nightmares that then lasted for several days.15
Human attempts to tinker with ecosystems by introducing new fish species often backfire in unexpected ways that accelerate the decline of the planet’s aquatic health. Consider what happened with the carp.
During the 1800s, fishermen in the midwestern United States introduced the common carp, native to other parts of the world, into the ecosystem, because this fish can grow to weigh dozens of pounds in muddy-bottomed lakes. In the 1960s, still other species of carp, such as the bighead and silver carp, were introduced into US ponds to eat the algae that had built up, mostly as a result of fertilizer runoff from agricultural lands.
As Science News reported on July 2, 2011, these species of carp have become invasive, crowding out other fish in the Mississippi and other river systems to near extinction. These carp can grow to one hundred pounds, every day eating up to 120 percent of their weight in plankton and algae, further depleting food sources for other species.16
Since 2010, city, state, and national governments have made desperate efforts to keep the carp from migrating upstream into the Great Lakes. The concern is that the carp will decimate the native fish populations in those bodies of water and catalyze the overall decline of ecosystems. Attempts have been made to stop the migration by erecting electrical underwater barriers at points where the lakes and river systems meet.17 Given the escape record of these fish over the years, there is little reason to believe they won’t end up invading the Great Lakes, once again demonstrating that nature, not humans, knows what is best for the natural balance of life.
Taxpayers in the United States and other countries contribute to overfishing and the decline of entire fish species because their governments provide large subsidies to the commercial fishing industry. In 2009 researchers with the Environmental Working Group (EWG) calculated that US taxpayers dole out nearly $1 billion each year in fishing subsidies from federal and state governments. The practice, EWG says, “is accelerating the ongoing collapse of fish stocks worldwide and adding to the devastation of large ocean fish species.”18
Nearly half of US fishing subsidies cover fishing fleet fuel costs, according to the EWG. Unlike truckers and motorists, commercial fishing fleets remain exempt from all state and federal fuel taxes, which encourages the fishing companies to keep as many ships out to sea as possible. An analysis by the World Bank found that, on average, each ton of fish caught requires about half a ton of fuel.19
Nearly one-third of the 269 monitored fish stocks in US waters are overfished, according to National Marine Fishery Service records from 1997 onward. The global situation is comparable—there are too many fishing boats chasing a diminishing number of fish. So governments subsidize fishermen, primarily salmon and tuna fishermen.20 Government policies like these should be among the first targets of those who work to bring about a change in global ecological consciousness.
The scientists attending the 2011 International Programme on the State of the Ocean put together a draft of recommendations for the governments of the world. They called for the following “urgent actions” to help restore the structure and function of marine ecosystems:
1. Reduce fishing to levels commensurate with long-term sustainability of fisheries and the marine environment.
2. Close fisheries that are not demonstrably managed following sustainable principles or that depend wholly on government subsidies.
3. Establish a globally comprehensive system of protected marine areas to conserve biodiversity, to build resilience, and to ensure ecologically sustainable fishing that leaves a minimal ecological footprint.
4. Prevent, reduce, and strictly control inputs into the marine environment of substances that are harmful or toxic to marine organisms.
5. Prevent, reduce, and strictly control nutrient inputs into the marine environment through better land and river catchment management and sewage treatment.
6. Avoid, reduce, or, at minimum, universally and stringently regulate oil, gas, aggregate, and mineral extraction from the oceans.
7. Properly and universally implement the precautionary principle by reversing the burden of proof so activities proceed only if they are shown not to harm the ocean singly or in combination with other activities.