‘It’s going to be grim, but there will still be coral’: Scientists call for realism about reefs
With coral reefs all over the world suffering ongoing bleaching and death at the hands of warming ocean waters — from remote coral atolls in the Indian Ocean to Australia’s iconic Great Barrier Reef — the future of these beloved marine ecosystems appears increasingly grim. But while experts almost universally agree that climate change will continue to shape the future of the world’s corals, some scientists insist that there’s still hope for them.
In a paper out Wednesday in the journal Nature, more than a dozen experts from around the world say that coral reefs are likely to undergo major changes as a result of continued climate change and other human activities, like fishing. But while future coral ecosystems might look a lot different than they do today, from the species they contain to the places they live, they aren’t necessarily doomed. In fact, accepting this transition and helping them through it might be the best — and even only way — to save them.
“What that paper does, it says yes, coral reefs are in enormous trouble, they’re gravely threatened by climate change and more local forms of human disturbance — but hey folks wake up, it’s not quite as bad as we’ve been yelling and screaming about,” said Jeremy Jackson, an emeritus professor at the Scripps Institute of Oceanography and one of the new paper’s authors. “And that’s important because what that means is we have more room for action and we see the possibility of a lot more benign outcome than we originally feared.”
Indeed, while coral reefs around the world are facing dire challenges, and many have experienced extensive bleaching and even death in the past few years, it’s important to avoid true alarmism, the authors suggest. Last October, for instance, Outside Magazine published a tongue-in-cheek obituary for Australia’s Great Barrier Reef, suggesting that it had been “killed off” by factors related to climate change. It was received with horror of many scientists, who quickly pointed out that while the reef has undergone dramatic changes — and large tracts of it have even been pronounced dead over the past year or so — it has certainly not yet been destroyed.
These are a few reasons not to panic, according to the experts:
The effects of climate change on coral reefs might not be as bad as we’ve predicted.
Many recent studies of climate change and coral have focused on a business-as-usual trajectory, according to Jackson — a scenario in which greenhouse gas emissions continue unabated into the future. The result is extreme levels of warming and ocean acidification, both of which put stress on coral reefs.
But while the world is a long way off from being able to meet its global climate goals under the Paris agreement — namely, keeping global temperatures within 2 degrees Celsius of their preindustrial levels — recent international efforts to reduce greenhouse gas emissions mean we’re no longer locked into a business-as-usual trajectory either. This means that the future for coral reefs might not be quite as dire as many recent studies have suggested, Jackson says.
“The trajectory is less than business as usual — it’s bad, but it’s not going to be as bad,” he told The Washington Post, adding that the progression of acidification may be less severe than previously predicted, and that there will may still be opportunity for corals to migrate to cooler parts of the ocean as well.
Coral reefs will be different in the future — and that’s okay.
While the authors advocate for minimizing the major drivers of coral stress, including climate change, unsustainable fishing and pollution, as much as possible, it’s clear that we can’t shield the world’s coral from everything forever. In particular, the progression of climate change will continue to have an impact on the oceans, even if it ends up being less dire than a business-as-usual scenario would predict.
This means that coral reefs are going to continue to react and change and adapt, and future reefs might look drastically different than they do today. But this is a survival tactic, and one that humans should embrace instead of fight, Jackson says.
Research has already shown that some types of coral are better at handling environmental stress than others. At many sites where bleaching events have occurred in the past few years, scientists have noticed that certain species tend to fare better than others, suggesting that they might have some kind of an evolutionary edge that helps them survive.
Scientists now say that, in the future, some of the species that are common today might begin to disappear and be replaced by hardier varieties. Additionally, some corals might be forced to migrate to cooler and more hospitable parts of the ocean. Instead of actively working to prevent these changes from happening, some scientists are now suggesting that allowing this transition process to happen — or even helping it along — may be for the best.
“For people that want to be nostalgic and turn time backwards and go to the way things used to be, that’s not gonna happen,” Jackson said. “There’s going to be extinctions, these newly forming reefs are going to be dominated by species that are in some way preadapted to these new conditions. So it’s going to be grim, but there will still be coral and there will still be coral reefs and we should be embracing that rather than just voicing despair.”
Actively managing reefs can make a big difference.
Because reefs will likely have to change to survive, some experts have suggested that it might even be a good idea to help this process along, perhaps by selectively breeding certain resilient species of coral and helping them to spread. The authors of the new paper note that “management and governance frameworks need to specifically embrace changes in the species composition of ecosystems or they will fail.”
In general, the authors suggest that more active strategies for management and conservation are key to the survival of coral reefs. Up to now, efforts to protect and manage reefs have been largely passive, the authors write, “relying on an implicit assumption that if reefs are protected from human impacts, they will return to their original condition following a disturbance.” But as it becomes increasingly clear that the environment will continue to change, potentially in some ways that may not be reversible, a new attitude approach may be in order.
In addition to allowing or helping reefs adapt to the changing climate, the authors recommend a more hands-on approach to the various other local disturbances that can put stress on corals — enacting more stringent fishing guidelines or pollution control efforts, for instance. While climate change is believed to be the biggest single factor in the degradation of reefs worldwide, there are numerous other issues that factor in from one location to the next. A better understanding and response to these local impacts may be critical to the survival of any individual reef.
On that note, Jackson also recommends an updated approach to the research of coral reefs — one that focuses increasingly on the cumulative impact of multiple disturbances working together (for instance, warming waters combined with pollution and overfishing) instead of focusing on one single factor at a time.
With a commitment to active management and an open mind about what the future of coral reefs might look like, scientists say we can now allow ourselves a little more optimism.
“I think the main point is that although the situation is bad, it’s really not hopeless,” Jackson said. “And we need to move away from the strict doom-and-gloom to focusing on the things that we can do to make a difference and setting realistic goals in that regard.”