In a groundbreaking analysis based on data extracted from hundreds of studies, scientists concluded that humans are on the verge of causing unprecedented and irreparable damage to the ocean environments. The patterns are clear, and extremely worrying, researchers say - but we still have time to act.
"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.
The science says that the oceans are suffering much more environmental damage than the land environments, but it's less visible to us, and so far, less species have gone extinct because it's easier to adapt in the ocean than in the land. This study compares compares the effects major changes in human history had on land-based wildlife to the effects out present day actions have on oceans, and they have found striking similarities.
The gross of the human damage to the environment was done after the industrial revolution. We started cutting forests, destroying habitats and causing global warming. Ocean species have been relatively protected from our impact, but things are looking worse and worse for them too. We may be indeed heading for a mass extinction - one caused by us.
But there is good news. While we are close to the point of no return, we're not quite there yet.
"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."
Dr. Pinsky, Dr. McCauley created a remarkable synthesis of existing studies, with laudable results. Other experts in the field are delighted with their efforts.
"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.
The most easily noticeable effect is on global fish stocks. Global fish stocks are exploited or depleted to such an extent that without urgent measures we may be the last generation to include fish in our diets - and this is not an overstatement. Most ocean species are already overharvested, and stocks have already been depleted. Coral reefs have also declined by 40 percent worldwide, mostly due to global warming and increased ocean acidification, caused by humans. Marine species are trying to adapt and migrate to cooler areas, but of course, this is not an option for corals.
"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."
The overall situation is pretty dire. Species on Earth are disappearing at a never-before seen rate in human history. The stark threat hangs over all species, be they on land – mammals, reptiles, birds, insects – or in the water. We still have some time to act... but we have to act now.
"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," said Stephen R. Palumbi of Stanford University, an author of the new study.. "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."