Ocean Life Faces Mass Extinction, Broad Study Says

A dead whale in Rotterdam, the Netherlands, in 2011. As container ships multiply, more whales are being harmed, a study said. Credit Marco De Swart/Agence France-Presse — Getty Images

A dead whale in Rotterdam, the Netherlands, in 2011. As container ships multiply, more whales are being harmed, a study said. Credit Marco De Swart/Agence France-Presse — Getty Images

By Carl Zimmer, New York Times

A team of scientists, in a groundbreaking analysis of data from hundreds of sources, has concluded that humans are on the verge of causing unprecedented damage to the oceans and the animals living in them.

“We may be sitting on a precipice of a major extinction event,” said Douglas J. McCauley, an ecologist at the University of California, Santa Barbara, and an author of the new research, which was published on Thursday in the journal Science.

But there is still time to avert catastrophe, Dr. McCauley and his colleagues also found. Compared with the continents, the oceans are mostly intact, still wild enough to bounce back to ecological health.

“We’re lucky in many ways,” said Malin L. Pinsky, a marine biologist at Rutgers University and another author of the new report. “The impacts are accelerating, but they’re not so bad we can’t reverse them.”

Scientific assessments of the oceans’ health are dogged by uncertainty: It’s much harder for researchers to judge the well-being of a species living underwater, over thousands of miles, than to track the health of a species on land. And changes that scientists observe in particular ocean ecosystems may not reflect trends across the planet.

Transplanted coral off Java Island, Indonesia. Great damage results from the loss of habitats like coral reefs, an analysis found. Credit Aman Rochman/Agence France-Presse — Getty Images

Transplanted coral off Java Island, Indonesia. Great damage results from the loss of habitats like coral reefs, an analysis found. Credit Aman Rochman/Agence France-Presse — Getty Images

Dr. Pinsky, Dr. McCauley and their colleagues sought a clearer picture of the oceans’ health by pulling together data from an enormous range of sources, from discoveries in the fossil record to statistics on modern container shipping, fish catches and seabed mining. While many of the findings already existed, they had never been juxtaposed in such a way.

A number of experts said the result was a remarkable synthesis, along with a nuanced and encouraging prognosis.

“I see this as a call for action to close the gap between conservation on land and in the sea,” said Loren McClenachan of Colby College, who was not involved in the study.

There are clear signs already that humans are harming the oceans to a remarkable degree, the scientists found. Some ocean species are certainly overharvested, but even greater damage results from large-scale habitat loss, which is likely to accelerate as technology advances the human footprint, the scientists reported.

Coral reefs, for example, have declined by 40 percent worldwide, partly as a result of climate-change-driven warming.

Some fish are migrating to cooler waters already. Black sea bass, once most common off the coast of Virginia, have moved up to New Jersey. Less fortunate species may not be able to find new ranges. At the same time, carbon emissions are altering the chemistry of seawater, making it more acidic.

“If you cranked up the aquarium heater and dumped some acid in the water, your fish would not be very happy,” Dr. Pinsky said. “In effect, that’s what we’re doing to the oceans.”

 Fragile ecosystems like mangroves are being replaced by fish farms, which are projected to provide most of the fish we consume within 20 years. Bottom trawlers scraping large nets across the sea floor have already affected 20 million square miles of ocean, turning parts of the continental shelf to rubble. Whales may no longer be widely hunted, the analysis noted, but they are now colliding more often as the number of container ships rises.

Mining operations, too, are poised to transform the ocean. Contracts for seabed mining now cover 460,000 square miles underwater, the researchers found, up from zero in 2000. Seabed mining has the potential to tear up unique ecosystems and introduce pollution into the deep sea.

The oceans are so vast that their ecosystems may seem impervious to change. But Dr. McClenachan warned that the fossil record shows that global disasters have wrecked the seas before. “Marine species are not immune to extinction on a large scale,” she said.

Until now, the seas largely have been spared the carnage visited on terrestrial species, the new analysis also found.

The fossil record indicates that a number of large animal species became extinct as humans arrived on continents and islands. For example, the moa, a giant bird that once lived on New Zealand, was wiped out by arriving Polynesians in the 1300s, probably within a century.

But it was only after 1800, with the Industrial Revolution, that extinctions on land really accelerated.

Humans began to alter the habitat that wildlife depended on, wiping out forests for timber, plowing under prairie for farmland, and laying down roads and railroads across continents.

Species began going extinct at a much faster pace. Over the past five centuries, researchers have recorded 514 animal extinctions on land. But the authors of the new study found that documented extinctions are far rarer in the ocean.

Before 1500, a few species of seabirds are known to have vanished. Since then, scientists have documented only 15 ocean extinctions, including animals such as the Caribbean monk seal and the Steller’s sea cow.

While these figures are likely underestimates, Dr. McCauley said that the difference was nonetheless revealing.

“Fundamentally, we’re a terrestrial predator,” he said. “It’s hard for an ape to drive something in the ocean extinct.”

Many marine species that have become extinct or are endangered depend on land — seabirds that nest on cliffs, for example, or sea turtles that lay eggs on beaches.

Still, there is time for humans to halt the damage, Dr. McCauley said, with effective programs limiting the exploitation of the oceans. The tiger may not be salvageable in the wild — but the tiger shark may well be, he said.

“There are a lot of tools we can use,” he said. “We better pick them up and use them seriously.”

Dr. McCauley and his colleagues argue that limiting the industrialization of the oceans to some regions could allow threatened species to recover in other ones. “I fervently believe that our best partner in saving the ocean is the ocean itself,” said Stephen R. Palumbi of Stanford University, an author of the new study.

The scientists also argued that these reserves had to be designed with climate change in mind, so that species escaping high temperatures or low pH would be able to find refuge.

“It’s creating a hopscotch pattern up and down the coasts to help these species adapt,” Dr. Pinsky said.

Ultimately, Dr. Palumbi warned, slowing extinctions in the oceans will mean cutting back on carbon emissions, not just adapting to them.

“If by the end of the century we’re not off the business-as-usual curve we are now, I honestly feel there’s not much hope for normal ecosystems in the ocean,” he said. “But in the meantime, we do have a chance to do what we can. We have a couple decades more than we thought we had, so let’s please not waste it.”

Idaho Sockeye Salmon Success Could Be A Blueprint

Approach could be used for other extinction fights

 

By Keith Ridler, Associated Press

BOISE, Idaho — Strategies used to bring back from the brink of extinction a population of central Idaho sockeye salmon have been so successful they could be used as a blueprint to prevent other extinctions, fisheries biologists say.

Thomas Flagg of the National Oceanic and Atmospheric Administration and Paul Kline of the Idaho Department of Fish and Game published their findings earlier this month in the journal Fisheries.

Scientists said a key strategy has been maintaining genetic diversity that has resulted in a greater number of sockeye with better survival skills, resulting in more fish returning to Redfish Lake.

“The survival advantages and apparent rapid increased fitness demonstrated by Sockeye Salmon hatched in Redfish Lake have allowed the development of realistic population triggers for the program’s expansion effort,” the report said. “This type of natural rebuilding scenario is the hoped for result when conservationists intervene to rescue depleted populations.”

Depleted in this case has a very precise number — 16. That’s how many wild adults — 11 males and five females — returned to the Sawtooth Valley from 1991 to 1998 and, through hatchery programs, ultimately produced more than 10,000 adult descendants.

The results showed this fall as some 1,400 endangered sockeye made the 900-mile journey from the Pacific Ocean to the lake in the Stanley Basin. That’s more than in any previous year going back nearly six decades.

The report estimates that at one time some 30,000 salmon made the trip to the 6,800-foot elevation Redfish Lake and several other lakes in the valley.

The numbers started declining, the study said, with intensification of commercial fisheries in the lower Columbia River.

A dam on the Salmon River built in the early 1900s blocked salmon for several decades from reaching Redfish Lake, itself named after the red-colored sockeye that once arrived there in abundance. Additional dams on the Snake and Columbia rivers added to the fish’s challenges in succeeding years.

The run was listed as endangered under the Endangered Species Act in 1991. That kicked off a hatchery program that scientists in the report said was able to retain about 95 percent of the genetic variability remaining in the population.

Besides genetic diversity, biologist also devised systems to raise the salmon in captivity.

“Although easily overlooked, a major program accomplishment was simply the development of fish culture protocols for rearing Sockeye Salmon full term to maturation,” the report said.

Captive sockeye have been reared at two locations. One is the Eagle Fish Hatchery in southwest Idaho run by the Idaho Department of Fish and Game. Fish have also been raised at the National Marine Fisheries Service facilities at the Manchester Research Station in Port Orchard.

While the program has relied on fish that never made the perilous trip to the ocean and back, it also produced an estimated 3.8 million eggs and fish for reintroduction to Sawtooth Valley lakes. Besides releasing young fish to head for the ocean, called smolts, releases also included adults let go annually to spawn naturally in Redfish Lake.

The report concluded that Redfish Lake could eventually produce enough naturally raised young fish to head to the ocean that enough would survive and return as adults to exceed “self-sustainability.”

Ultimately the recovery plan is to have 1,000 or more fish spawning in Redfish Lake for multiple generations, and at least 500 spawning in one of four other lakes in the basin.

The report said that when enough adult salmon start returning to Redfish Lake, efforts could begin to bring sockeye salmon back to nearby Pettit and Alturas lakes.

Ocean acidification due to carbon emissions is at highest for 300m years

Coral is particularly at risk from acidification and rising sea temperatures. Photo: Paul Jarrett/PA

Coral is particularly at risk from acidification and rising sea temperatures. Photo: Paul Jarrett/PA

By Fiona Harvey, The Guardian

The oceans are more acidic now than they have been for at least 300m years, due to carbon dioxide emissions from burning fossil fuels, and a mass extinction of key species may already be almost inevitable as a result, leading marine scientists warned on Thursday.

An international audit of the health of the oceans has found that overfishing and pollution are also contributing to the crisis, in a deadly combination of destructive forces that are imperilling marine life, on which billions of people depend for their nutrition and livelihood.

In the starkest warning yet of the threat to ocean health, theInternational Programme on the State of the Ocean (IPSO) said: “This [acidification] is unprecedented in the Earth’s known history. We are entering an unknown territory of marine ecosystem change, and exposing organisms to intolerable evolutionary pressure. The next mass extinction may have already begun.” It published its findings in the State of the Oceans report, collated every two years from global monitoring and other research studies.

Alex Rogers, professor of biology at Oxford University, said: “The health of the ocean is spiralling downwards far more rapidly than we had thought. We are seeing greater change, happening faster, and the effects are more imminent than previously anticipated. The situation should be of the gravest concern to everyone since everyone will be affected by changes in the ability of the ocean to support life on Earth.”

Coral is particularly at risk. Increased acidity dissolves the calcium carbonate skeletons that form the structure of reefs, and increasing temperatures lead to bleaching where the corals lose symbiotic algae they rely on. The report says that world governments’ current pledges to curb carbon emissions would not go far enough or fast enough to save many of the world’s reefs. There is a time lag of several decades between the carbon being emitted and the effects on seas, meaning that further acidification and further warming of the oceans are inevitable, even if we drastically reduce emissions very quickly. There is as yet little sign of that, with global greenhouse gas output still rising.

Corals are vital to the health of fisheries, because they act as nurseries to young fish and smaller species that provide food for bigger ones.

Carbon dioxide in the atmosphere is absorbed by the seas – at least a third of the carbon that humans have released has been dissolved in this way, according to the Intergovernmental Panel on Climate Change – and makes them more acidic. But IPSO found the situation was even more dire than that laid out by the world’s top climate scientists in theirlandmark report last week.

In absorbing carbon and heat from the atmosphere, the world’s oceans have shielded humans from the worst effects of global warming, the marine scientists said. This has slowed the rate of climate change on land, but its profound effects on marine life are only now being understood.

Acidification harms marine creatures that rely on calcium carbonate to build coral reefs and shells, as well as plankton, and the fish that rely on them. Jane Lubchenco, former director of the US National Oceanic and Atmospheric Administration and a marine biologist, said the effects were already being felt in some oyster fisheries, where young larvae were failing to develop properly in areas where the acid rates are higher, such as on the west coast of the US. “You can actually see this happening,” she said. “It’s not something a long way into the future. It is a very big problem.”

But the chemical changes in the ocean go further, said Rogers. Marine animals use chemical signals to perceive their environment and locate prey and predators, and there is evidence that their ability to do so is being impaired in some species.

Trevor Manuel, a South African government minister and co-chair of the Global Ocean Commission, called the report “a deafening alarm bell on humanity’s wider impacts on the global oceans”.

“Unless we restore the ocean’s health, we will experience the consequences on prosperity, wellbeing and development. Governments must respond as urgently as they do to national security threats – in the long run, the impacts are just as important,” he said.

Current rates of carbon release into the oceans are 10 times faster than those before the last major species extinction, which was the Paleocene-Eocene Thermal Maximum extinction, about 55m years ago. The IPSO scientists can tell that the current ocean acidification is the highest for 300m years from geological records.

They called for strong action by governments to limit carbon concentrations in the atmosphere to no more than 450 parts per million of carbon dioxide equivalent. That would require urgent and deep reductions in fossil fuel use.

No country in the world is properly tackling overfishing, the report found, and almost two thirds are failing badly. At least 70 per cent of the world’s fish populations are over-exploited. Giving local communities more control over their fisheries, and favouring small-scale operators over large commercial vessels would help this, the report found. Subsidies that drive overcapacity in fishing fleets should also be eliminated, marine conservation zones set up and destructive fishing equipment should be banned. There should also be better governance of the areas of ocean beyond countries’ national limits.

The IPSO report also found the oceans were being “deoxygenated” – their average oxygen content is likely to fall by as much as 7 per cent by 2100, partly because of the run-off of fertilisers and sewage into the seas, and also as a side-effect of global warming. The reduction of oxygen is a concern as areas of severe depletion become effectively dead.

Rogers said: “People are just not aware of the massive roles that the oceans play in the Earth’s systems. Phytoplankton produce 40 per cent of the oxygen in the atmosphere, for example, and 90 per cent of all life is in the oceans. Because the oceans are so vast, there are still areas we have never really seen. We have a very poor grasp of some of the biochemical processes in the world’s biggest ecosystem.”

The five chapters of which the State of the Oceans report is a summary have been published in the Marine Pollution Bulletin, a peer-reviewed journal.

Is climate change humanity’s greatest-ever risk management failure?

By Dana Nuccitelli, Grist

Humans are generally very risk-averse. We buy insurance to protect our investments in homes and cars. For those of us who don’t have universal healthcare, most purchase health insurance. We don’t like taking the chance — however remote — that we could be left unprepared in the event that something bad happens to our homes, cars, or health.

Climate change seems to be a major exception to this rule. Managing the risks posed by climate change is not a high priority for the public as a whole, despite the fact that a climate catastrophe this century is a very real possibility, and that such an event would have adverse impacts on all of us.

For example, in my job as an environmental risk assessor, if a contaminated site poses a cancer risk to humans of more than 1-in-10,000 to 1-in-1 million, that added risk is deemed unacceptably high and must be reduced. This despite the fact that an American man has a nearly 1-in-2 chance of developing and 1-in-4 chance of dying from cancer (1-in-3 and 1-in-5 for an American woman, respectively).

To that 42 percent chance of an average American developing cancer in his or her lifetime, we’re unwilling to add another 0.001 percent. The reason is simple — we really, really don’t want cancer, and thus consider even a small added risk unacceptable.

Yet we don’t share that aversion to the risks posed by human-caused climate change. These risks include more than half of global species potentially being at risk of extinction, extreme weather like heat waves becoming more commonplace, global food supplies put at risk by this more frequent extreme weather, glaciers and their associated water resources for millions of people disappearing, rising sea levels inundating coastlines, and so forth.

This isn’t some slim 1-in-a-million risk; we’re looking at seriously damaging climate consequences in the most likelybusiness-as-usual scenario. The forthcoming fifth IPCC report is likely to state with 95 percent confidence that humans are the main drivers of climate change over the past 60 years, and the scientific basis behind this confidence is quite sound. It’s the result of virtually every study that has investigated the causes of global warming.

The percentage contribution to global warming over the past 50-65 years is shown in two categories, human causes (left) and natural causes (right), from various peer-reviewed studies (colors).
The percentage contribution to global warming over the past 50-65 years is shown in two categories, human causes (left) and natural causes (right), from various peer-reviewed studies (colors).

Yet in a recent interview with NPR, climate scientist Judith Curry, who has a reputation for exaggerating climate science uncertainties, claimed that based on those uncertainties, “I can’t say myself that [doing nothing] isn’t the best solution.”

This argument, made frequently by climate contrarians, displays a lack of understanding about risk management. I’m uncertain if I’ll ever be in a car accident, or if my house will catch fire, or if I’ll become seriously ill or injured within the next few years. That uncertainty won’t stop me from buying auto, home, and health insurance. It’s just a matter of prudent risk management, making sure we’re prepared if something bad happens to something we value. That principle should certainly apply to the global climate.

Uncertainty simply isn’t our friend when it comes to risk. If uncertainty is large, it means that a bad event might not happen, but it also means that we can’t rule out the possibility of a catastrophic event happening. Inaction is only justifiable if we’re certain that the bad outcome won’t happen.

Curry is essentially arguing that she’s not convinced we should take action to avoid what she believes is a very possible climate catastrophe. That’s a failure of risk management. I wonder if she would also advise her children not to buy home or auto or health insurance. Maybe they’ll be a wasted expense, or maybe they’ll prevent financial ruin in the event of a catastrophe.

Climate change presents an enormous global risk, not in an improbable 1-in-a-million case, but rather in the most likely scenario. From a risk management perspective, our choice could not be clearer. We should be taking serious steps to reduce our impact on the climate via fossil fuel consumption and associated greenhouse gas emissions. But we’re not. This is in large part due to a lack of public comprehension of the magnitude of the risk we face; a perception problem that social scientists are trying to determine how to overcome.

At the moment, climate change looks like humanity’s greatest-ever risk management failure. Hopefully we’ll remedy that failure before we commit ourselves to catastrophic climate consequences that we’re unprepared to face.