"I want to study coral reefs, but, I hear that they probably won't be around for much longer, so I am not so sure that is such a good career choice." Prospective student, Steve Palumbi's office, a few months back.
Dr. Steve Palumbi is not easily ruffled. A veteran field scientist, he has taken on Japan's powerful whaling industry (conducting clandestine tests of commercially sold whale meat by cloning the DNA in hotel bathrooms to accommodate CITES restrictions)-- and successfully exposing the rampant illegal hunting that exists. He has used molecular techniques to determine historic abundances of whales, challenging pro-whaling countries' argument that some species have receovered enough to lift the global moratorium. But, all this experience didn't prepared him for that prospective student's decidedly depressing proclamation about an inevitable demise of coral reefs.
The surprise comes because we coral reef scientists know that while the news about climate change is dire, and the future of coral reefs is disturbingly precarious, it is not yet written. I say this not out of a desperate, deluded hope--I'm no Scarlett O'Hara fantasizing that Rhett may just come back. My certainty is grounded in the evidence of corals' natural capacity to adapt and the potential that still exists within the policy realm to halt further climate change (granted, the latter requires a slightly more desperate form of hope than the former).
But this perspective is clearly lacking in the next generation of would-be coral reef ecologists and likely lacking in the public at large. It's the unfortunate consequence of warnings gone awry: instead of motivating people to act to stop the worst, dire predictions result in a passive acquiescence that defeat is inevitable.
But coral reefs not destined to disappear, and certainly not by a force beyond our control.
Take the reefs of Ofu, in American Samoa. Dr. Palumbi described how periodic exposure throughout the year to pulses of warmer water seems to have conditioned resident corals to have greater resistance to bleaching than nearby corals occupying a different and cooler lagoon pool. So some corals may be able to adapt to warming waters caused by climate change, at least to changes predicted for the next few years to decades.
And the same may be true for ocean acidification. In the session, "Will Coral Reefs Disappear? Separating Fact from Conjecture," water chemistry data across the reefs of Bermuda showed there were significant seasonal effects. So while continued unabated acidification of seawater will undoubtedly lead to dissolving coral reefs, the frequent and regular exposure to more acidified waters in the summertime may allow for corals in Bermuda to adapt to global ocean acidification more readily than we might have first thought.
This is the silver lining along the edge of the darkening storm cloud: reefs on the margins may serve as refuges of hope, and not just canaries in the coal mine. In other words, living on the edge (in terms of geographic distribution, depth, water quality or other environmental parameter), may confer resilience or resistance to corals that will help them hold out against climate change for longer than we anticipated.
But not forever. It's an intelligent optimism we hold, bound by the realities that the situation is indeed, grave. We must act now to protect potential refuges from other stressors (such as coastal development) as we continue to work to stop climate change. Not to act is to resign coral reefs to the realm of paleontologists.
So to the future grad students or the despondent masses out there: those who know the most continue to push for action, to argue that coral reefs have not yet given up the ghost (though they may indeed be changed). I spent all day in those lectures halls and can assure you there were no fat ladies singing. Until the experts say the gig is up, I say we stay the course and keep working for solutions.
Photo credit: Tim Taylor