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.”

New Ocean Forecast Could Help Predict Fish Habitat Six Months in Advance

People are now used to long-term weather forecasts that predict what the coming winter may bring. But University of Washington researchers and federal scientists have developed the first long-term forecast of conditions that matter for Pacific Northwest fisheries.

By Hannah Hickey | University of Washington News and Information

September 4, 2013

“Being able to predict future phytoplankton blooms, ocean temperatures and low-oxygen events could help fisheries managers,” said Samantha Siedlecki, a research scientist at the UW-based Joint Institute for the Study of the Atmosphere and Ocean.

“This is an experiment to produce the first seasonal prediction system for the ocean ecosystem. We are excited about the initial results, but there is more to learn and explore about this tool – not only in terms of the science, but also in terms of its application,” she said.

A school of sardines. The tool will soon produce a months-long outlook for Pacific Northwest sardine habitat.Image-Wikimedia / Alessandro Duci - See more at: http://alaska-native-news.com/alaska-native-news-at-sea/9212-new-ocean-forecast-could-help-predict-fish-habitat-six-months-in-advance.html#sthash.JjthM2LO.dpuf
A school of sardines. The tool will soon produce a months-long outlook for Pacific Northwest sardine habitat.Image-Wikimedia / Alessandro Duci

In January, when the prototype was launched, it predicted unusually low oxygen this summer off the Olympic coast. People scoffed. But when an unusual low-oxygen patch developed off the Washington coast in July, some skeptics began to take the tool more seriously. The new tool predicts that low-oxygen trend will continue, and worsen, in coming months.

“We’re taking the global climate model simulations and applying them to our coastal waters,” saidNick Bond, a UW research meteorologist. “What’s cutting edge is how the tool connects the ocean chemistry and biology.”

Bond’s research typically involves predicting ocean conditions decades in advance. But as Washington’s state climatologist he distributes quarterly forecasts of the weather. With this project he decided to combine the two, taking a seasonal approach to marine forecasts.

The National Oceanographic and Atmospheric Administration funded the project to create the tool and publish the two initial forecasts.

“Simply knowing if things are likely to get better, or worse, or stay the same, would be really useful,” said collaborator Phil Levin, a biologist at NOAA’s Northwest Fisheries Science Center.

Early warning of negative trends, for example, could help to set quotas.

“Once you overharvest, a lot of regulations kick in,” Levin said. “By avoiding overfishing you don’t get penalized, you keep the stock healthier and you’re able to maintain fishing at a sustainable level.”

/tmp/tpc2e91792_36e0_416e_b69a_7de0af3744c9.psThe tool is named the JISAO Seasonal Coastal Ocean Prediction of the Ecosystem, which the scientist dubbed J-SCOPE. It’s still in its testing stage. It remains to be seen whether the low-oxygen prediction was just beginner’s luck or is proof the tool can predict where strong phytoplankton blooms will end up causing low-oxygen conditions, Siedlecki said.

The tool uses global climate models that can predict elements of the weather up to nine months in advance. It feeds those results into a regional coastal ocean model developed by the UW Coastal Modeling Group that simulates the intricate subsea canyons, shelf breaks and river plumes of the Pacific Northwest coastline. Siedlecki added a new UW oxygen model that calculates where currents and chemistry promote the growth of marine plants, or phytoplankton, and where those plants will decompose and, in turn, affect oxygen levels and other properties of the ocean water.

The end product is a nine-month forecast for Washington and Oregon sea surface temperatures, oxygen at various depths, acidity, and chlorophyll, a measure of the marine plants that feed most fish. Coming this fall are sardine habitat maps. Eventually researchers would like to publish forecasts specific to other fish, such as tuna and salmon.

The researchers fine-tuned their model by comparing results for past seasons with actual measurements collected by theNorthwest Association of Networked Ocean Observing Systems, or NANOOS. The UW-based association is hosting the forecasts as a forward-looking complement to its growing archive of Pacific Northwest ocean observations.

Siedlecki’s analyses suggest the new tool is able to predict elements of the ocean ecosystem up to six months in advance.

Researchers will present the project this year to the Pacific Fishery Management Council, the regulatory body for West Coast fisheries, and will work with NANOOS to reach tribal, state, and local fisheries managers.

If the forecasts prove reliable, they could eventually be part of a new management approach that requires knowing and predicting how different parts of the ocean ecosystem interact.

“The climate predictions have gotten to the point where they have six-month predictability globally, and the physics of the regional model and observational network are at the point where we’re able to do this project,” Siedlecki said.

Source: University of Washington