Climate change and our insatiable appetite for seafood could lead to mass extinctions of marine life and some pretty crazy new oceanscapes.
That’s the finding of a recent analysis that looked at data from hundreds of different sources on marine life and changes to the world’s oceans.
“We may be sitting on a precipice of a major extinction event,” Douglas J. McCauley, ecologist at the University of California, Santa Barbara, and an author of the new research, told the New York Times.
The research, published in the recent issue of the journal Science, says the oceans could rebound from current conditions, probably better than the mass extinctions happening on land. But it’s significantly more difficult to track the health of sea animals than those on land.
“There are clear signs already that humans are harming the oceans to a remarkable degree,” the Times notes. “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.”
One such example is the loss of coral reefs, which have declined by 40 percent, due mostly to climate change.
Fish are facing a number of challenges as well. “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,” reports the Times. “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.”
Mangroves are being replaced with fish farms, which already account for a significant percentage of fish in the food supply, and experts estimate they’ll provide most of the fish consumed by humans in the next 20 years. Fish farms bring their own set of consequences to oceans much in the same way factory farms pollute land – and there are other issues. Again, the Times:
“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.”
There are also issues being caused by all the plastic debris in the oceans—much of it winding up in the digestive systems of fish and birds.
But the analysis also found there is much we can do to reverse the damage.
“We’re lucky in many ways,” Malin L. Pinsky, a marine biologist at Rutgers University and another author of the report told the Times. “The impacts are accelerating, but they’re not so bad we can’t reverse them.”
The scientists say reducing our carbon emissions is going to make a huge difference in the health of the oceans.
“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,” Stephen R. Palumbi of Stanford University, an author of the study told the Times. “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.”
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