The Underwater Industrial Revolution Is Driving Ocean Life to Extinction
Humans have pushed hundreds of land animals into extinction. Is it too late to save marine wildlife from the same fate?
Dead fish. Image: Mahalie Stackpole.
The idiom "there's plenty of fish in the sea" is poised to become an irrelevant throwback, according to a new study published today in Science. The study's authors, led by the UC Santa Barbara ecologist Douglas McCauley, warn that oceanic wildlife may suffer the same catastrophic die-offs experienced by that legions of land animals that have been edged out by human activity. The only difference is that it has taken humans a few centuries longer to industrialize the ocean, compared to our relatively rapid takeover of the land.
"We are setting ourselves up in the oceans to replay the process of wildlife Armageddon that we engineered on land," McCauley said in a UCSB statement.
McCauley and his colleagues point out that over the last few hundred years, the devastating environmental effects of industrialization and agriculture have demolished many land ecosystems. "There was a sharp acceleration [of extinction] about the time of the Industrial Revolution," McCauley told me.
"Rates of extinction have increased even more since the Industrial Revolution, but it seems to have been a major turning point in terms of historical terrestrial extinction rates," he continued. "This was associated with a global transition on land towards rapidly altering terrestrial wildlife habitat."
Meanwhile, large-scale industrialization of the oceans has only begun. Shrimp and fish farms suck their feeding grounds dry of resources just as livestock do on land, and fishing lines hundreds of miles long trawl the waters, destabilizing the ecosystems they encounter. Ocean floor mining and other industrial processes are also contributing to a global disrupting wildlife in the seas. And that's without even getting into the threat posed by human-driven climate change.
Indeed, the more contact an oceanic species has with humans, the more threatened it is likely to be. "An interesting point to come out of these comparisons was that any time that a marine animal associates with land in any way—e.g. sea turtles laying eggs on beaches—their risk for extinction goes up," McCauley told me. "Of course that is because that increases rates of interaction between humans and this class of marine animals."
Sea turtles and shorebirds, for example, are more threatened at the moment than marine invertebrates. But that doesn't mean purely aquatic species are safe over the long term. "It is worth noting that we can't take comfort in the fact that there have been relatively few marine invertebrate extinctions," McCauley said. "The fact of the matter is that they are more of a black box for those assessing risk—we have an extremely deficient view of the risk that marine invertebrates are facing."
The notion that humanity is in the process of devastating the oceans is depressing, no question. But fortunately, McCauley's team presented no shortage of strategies for staving off an aquatic extinction event. The one silver lining of losing some 500 terrestrial species to human expansion is that we can learn from the mistakes of our forebears.
In that regard, the first step is also the hardest: getting people to accept the severity of the situation. "We all need to develop an awareness that if we don't act now, we are going to have a major marine wildlife mess on our hands in 100 years," McCauley told me.
One of the best ways to get the message across is to emphasize the human cost of biodiversity loss. This is not an esoteric threat; it's a problem that will inevitably come back to bite us.
"Protecting marine wildlife isn't a selfless enterprise," said McCauley. "Marine animals provide an important part of our global food budget, particularly in impoverished areas. They are critically important to buffering cities from storm damage, storing carbon, and supporting jobs. Keeping marine wildlife healthy also appears to make it easier to protect terrestrial wildlife from even more damage. The list goes on and on."
The authors of the Science paper also suggested numerous managerial strategies for curbing ocean extinctions. Establishing protected reserves and parks has been critical in preserving land-based species, and the oceans are no different. Bigger reserves will have to be set aside for marine animals—and lots of them, because right now, there is far less protected real estate in the oceans than on land.
Along those lines, we need better policies for safeguarding biodiversity in unprotected waters. "We need to manage carefully this anticipated explosion in marine industry—the marine Industrial Revolution," said McCauley. "We need minerals, energy, and food from the sea but we have to thoughtfully manage and zone rapid growth forecasted in marine farming, marine mining, and marine energy prospecting so that it doesn't pummel ocean wildlife populations as this growth did on land."
Finally, the ultimate challenge: slowing human-driven climate change. It's already well-established that rising water temperatures and acidification threaten the ocean ecosystems across the globe. Without more aggressive action to confront rising temperatures, biodiversity will plummet in and out of the seas. And given how embarrassingly inept the US Congress is on this issue, there is a lot more work to be done.
That's why McCauley stresses that the first step—raising widespread awareness—is still the most vital, plus it is the easiest way for the average person to get involved. "Simply building recognition of this, is in my opinion, the most important part of this," he told me. "We sat back on our heels on climate change letting the problem get so bad it became a monumental global effort to fix. It was about the same story for terrestrial wildlife."
"We have to nip this marine wildlife crisis in the bud," he said.