SciCafe: A Bright Future for Our Oceans? with Jeremy Jackson
JEREMY JACKSON (EMERITUS PROFESSOR OF OCEANOGRAPHY, SCRIPPS INSTITUTION OF OCEANOGRAPHY): Good evening, everybody. I want to do something slightly different tonight. I want to talk about how the oceans have changed in the 55 to 60 years that I’ve been looking at the oceans as a scientist, and it’s a kind of a personal story, a metamorphosis from being a young kid who is excited by the mystery and beauty of the ocean and trying to understand how ecosystems worked, to watching those things start to change while I was still in my 30s and getting really angry and depressed about it. And working on coral reefs is not the most optimistic thing to be doing right now. And then sort of coming out of that and trying to get over the history and think about what are the prospects for the ocean in the future, what we can do about it, and not cry about the past but really try and move on. So that’s what I’m going to try to do today.
I began there in the summer of 1968, that shack on the beach. The Discovery Bay Marine Laboratory is where modern coral reef science began. And utterly transformational in terms of the understanding of how coral reefs work. And it was founded by a great guy named Tom Goreau and situated where it was because that was what you could see when you went diving immediately offshore.
That is something that nobody can see today. Those are reefs from five meters down to 25 meters, with 50, 60, 70, even 90 percent cover of live coral. And I’ll show you pictures of what they look like today, and it’s really very sad. I studied stuff that was exciting to maybe 12 people in the whole world. I was really interested in—well, given that the whole reef was covered by living coral, if one thing’s going to grow, something else has got to get smaller or die.
And so I spent about 15 years of my life studying the competitive interactions for space among corals and sponges and things called bryozoans, and it’s really baroque and it’s really complicated, and it was a lot of fun. Coral is overgrowing that sponge, very carefully not touching it, because if it touches, the sponge is toxic to the coral. But it eventually overgrows it and it wins.
And then these things in the bottom which are called bryozoans, think of them as species A, B, and C. They’re like a game of rock, paper, scissors, because A beats B; B beats C; but C beats A. and the discovery of these things which we called competitive networks played a major role in the understanding of the maintenance of diversity on coral reefs, why competition doesn’t eliminate all but a few species.
And it wasn’t static, like in those pictures. So this is a world about this big, over one year, from June 1983 to May 1984, and it doesn’t matter what those organisms are, but you can see they‘ve moved around, some of them have been eaten, some have overgrown. Other things, some have poisoned their neighbors. It’s a very aggressive picture, and it was a hell of a lot of fun to study.
But then in the summer of 1980, we had a storm, Hurricane Alan, the second-strongest hurricane ever recorded in the Western Atlantic. The picture in the upper left was taken from my wife’s and my house, where we put up about 40 of the scientists at the lab. Looking down from a hill, those trees are about 70 or 80 feet high, and that wave in the center is a hell of a lot taller than those trees.
As a consequence of that storm, the next day the whole bay smelled of death. There were new islands that were formed of the carcasses, the skeletons of the corals, and in the bottom left you can see these things that were just rolled around like soccer balls or something. And if you look at the pictures on the right, on the left is before the storm and on the right is after the storm, and you can see the hurricane was much worse for branching corals that are more fragile than massive ones.
Well, we thought we were really smart. We’d been studying coral reefs for a long time. We thought we understood what was going on. And of course, hurricanes are a natural phenomenon. They’ve been happening for billions of years on the earth. And so we wrote this paper that was published in Science about all the damage caused by the storm, and then we confidently predicted how the coral reefs would recover from it because after all, they had always recovered for millions of years. But we got it all wrong, because the coral reefs didn’t recover.
And so what that did, that was like the light bulb going off, the epiphany of realizing that the reason the corals weren’t recovering was because of all these things that people had been doing that were impacting the oceans, that had been slowly accumulating. And so when a natural disturbance happened, rather than having the natural succession of replacement and the rebuilding of the coral reefs, it just went downhill really bad.
Now, one of the reasons that happened was because of overfishing. These are amazing photographs. I actually grew up in Miami for a while, and in the 1950s, people would go out for one afternoon in a day boat in Key West and come back, and they would put the biggest fish they caught on that board. Well, this woman, Lauren McClennahan, who was my student, she discovered the 70-year record of daily photographs, and she analyzed them. So in the 1950s you couldn’t win a prize if your fish didn’t weigh 200 or 250 pounds. By the 1970s, you don’t see any of those really big fish, but it still looks really cool. And then by 2007, a couple years before the paper was written, you’ve got minnows.
And the irony is that people were paying more in 1950 dollars to catch minnows than they were paying in the past to catch these gigantic fish, and they had no idea of how it’s changed. It’s what we call shifting baselines, that everybody thinks the way the world is when they’re 15 years old is natural. And everything that happens afterwards is unnatural, which is why I’m more depressing than the young people in this room.
But since we all know that kids never listen to their parents, they make the same damn mistakes. And they think that natural is the way it was when they were 15 years old. And so generation by generation, we really screw up nature because we have no inkling of the way things were before.
Now, that’s just on coral reefs in Key West but try the entire Atlantic Ocean. So what you have here is a reconstructed history of fish abundance, from 1900 to 2000. Red is really good. Pale blue is really bad. Let’s see if I can do this without turning it off again. No, I can’t see it.
Two world wars were fought about the cod in Newfoundland and Nova Scotia. I mean, the British beat the French twice. They gave it back once and they kept it the second time, because cod was the second most valuable commodity in the world after sugar, for over 100 years. And look at it now. And yet, fishers still talk about how there’s a lot of fish out there and we don’t need to be regulated, but I think the picture makes it pretty clear they’re wrong.
There are dead zones forming in the coastal ocean, and they’re really, really spooky. So every one of those red dots is something called a dead zone. So what’s a dead zone? We’ve got all this fertilizer coming down into the ocean and rivers because of modern agriculture, which uses way too much fertilizer, totally unnecessary. And so all this nitrogen and phosphorus comes into the coastal zones, and in a lot of developing countries or in New York City until not that long ago, the poop just went right into the river.
And as a consequence of all that, you get—you know if you put fertilizer on a lawn, if you have a lawn, the grass grows better. Well, if you put all that nitrogen and phosphorus into the coastal ocean, the phytoplankton and the seaweed grow better. And it grows so much better, and so fast, that the things that eat them can’t keep up.
So they do a very unnatural thing: they die of old age. And then they sink to the bottom and then the bacteria find them and they start to break them down. In other words, they rot. But as a consequence of rotting, the bacteria used up all the oxygen, and before you know it, there’s no oxygen or very little oxygen in the deep water. And as a consequence, anything that can’t swim away is dead.
And when I started giving these charming, optimistic talks, there were about 250 dead zones. There are now close to 600 dead zones. And if you look where they are, it’s pretty clear that modern capitalistic industrial economies are the driving force, because the entire East and Gulf Coast of the United States, Western Europe, Japan, Brazil is getting there—and it’s just happening and happening and happening. Everywhere. And it’s bad news.
There’s also this phenomenon of diseases that are starting to appear. Now, in that picture on the left, I took that picture about—in, my God, in 1981 or 1982, and there were still these abundant black sea urchins, which we really didn’t like very much because the spines hurt like hell if you got them. And you can see there are like 15 of them in that picture, and you cannot see any seaweed, because those sea urchins are grazing on the seaweed.
And then in 2003, actually while my wife and I were back here in New York to get married, the epidemic disease hit in Jamaica and all the sea urchins died. Just died. In one year, it moved around the entire Caribbean and trillions—who knows how many sea urchins—died. And that was really bad in terms of explosions of algae.
And then what you see on the bottom, I mean, the colors are really beautiful, but that’s death. That’s black band disease on the left and yellow band disease on the right. And what those are, are corals that are dying of these diseases we barely understand. And there were diseases before, but all of a sudden this is happening all over. In St. Croix, most of the corals are sick from disease, and it seems to get worse.
And then the last in this litany of charming stuff is coral bleaching. Because as the oceans are getting warmer, all they have to do is get a little bit warmer, like say two degrees Fahrenheit warmer than the normal maximum. And if they stay that way for a month or so, corals start to bleach. Now, what does that mean?
A coral is a symbiosis between the coral animal that you see, all those tiny polyps, the colonies that make the coral, and algae. Actually they’re dinoflagellates that live symbiotically within the tissue of the coral. And it’s a bargain. The corals provide nutrients for the plants, like fertilizer for those algae, and provides protection from predators; and the algae feed junk food to the corals.
They photosynthesize, they make sugar. And most of the sugar they make goes to the coral. The corals can’t live without it, which is really bad, because if it gets a little bit too hot, the algae can’t make the sugar and give it to the corals. And the corals then say, you didn’t pay the rent. And so they kick them out, and that’s coral bleaching, because they look white, because the color from the symbionts is gone.
And if it doesn’t cool off and if there isn’t the opportunity for algae to re-colonize the corals, they’re dead. And you may have heard about the great bleaching on the north coast of Australia a year and a half ago. It was pretty awful. So as a result, my Caribbean reefs that used to look like that picture in the upper left, or in Florida, the upper right, now look like this. And so you’ve gone from 50, 70 percent live coral to 80, 90 percent live seaweed and slime.
And I wrote a paper about this which I called “The Rise of Slime,” because basically the history of people in relation to the oceans was, there used to be a lot of big animals. Well, we got them. We ate ‘em. And there used to be a lot of three-dimensional structures: coral reefs, mangrove forests, seagrass beds, kelp forests, things like that. Well, they’ve sort of disappeared, and what’s replacing them? Jellyfish and bacteria. It’s like we’re reversing half a billion years of evolution, going back to the beginning of the Cambrian, and we’ve done it in 100 years. Aren’t people amazing?
Okay. I spent about 13, 14 years before I gave this talk, going around talking about this stuff. So I gave this TED Talk and they called me Dr. Doom. It was all over after that. Okay. But the problem is, it doesn’t do a lot of good to just dwell on what was. And so the question is—and this is something a lot of us “old” people are really struggling with. I mean, there are still young people who go out and dive on a coral reef and there’s a little bit of living coral and there’s some beautiful sponges, and say, oh, my God, it was the most beautiful thing I ever saw. And the little gobies that are this big are really brightly colored, and they say wow, look at that. Old copies of Skin Diver magazine had vistas of coral reefs as far as the light would allow you to take the picture. Now they’re all close-ups of little tiny things in places with bright colors because you couldn’t take those pictures anymore.
So at any rate, I guess what I want to emphasize is it’s not all bad news. And this cartoon, which is from a paper actually that a bunch of us wrote, it was called, “Are U.S. Coral Reefs On a Slippery Slope to Slime?” And the answer, of course, was yes. And then the question was, what can we do about it? And so we talked about the things that were more tractable or not.
But it really is sort of a model of the way the ocean has changed. You’ve got all that nice stuff and clear water on the left, and you’ve got this mess on the right. And so can we get out of the right? Can we go to the left? I’d like to think we could really go to the left, but that’s another story. Okay.
Okay, so the poster child of extraordinary success is this little place called Cabo Pulmo in the southern tip of Baja, California. A little village of people who have been fishing for hundreds of years. And there were basically no fish left, and they were all going to leave.
And then they said, why don’t we do something. Why don’t we stop fishing? And so they stopped fishing—and how they survived I’m not entirely sure; maybe they got a grant, I don’t know. But they stopped fishing, and if anybody came in and tried to fish, well, let’s say their boats went under water and people didn’t come back.
And in 10 years—in 10 years, there was a 500 percent increase in the abundance of fish. I’m going to show you pictures in a second. It is gorgeous. And the income, the average income, and that includes kids, went up to $18,000 a year, because people like some of you in this room were willing to pay a ton of money to go dive in this place that looked the way it should have looked like, but almost no place looks like that anymore.
And here, you can see it in the pictures. So that’s the very arid climate of Southern Baja, California. The upper right, those are schools of sharks that are longer than I am tall. That may spook you, but that is a sign of health in the ocean. That is like an A-plus sign of a healthy ecosystem. That’s not a staged photograph. That’s not in an aquarium. That lower left photograph is the abundance of the fishes at Cabo Pulmo.
And you know, I work on corals, and for a long time people argued about whether or not corals could make it in the Gulf of California; it was too cold. Well, maybe it was because it was screwed up, because the corals are doing really well in Cabo Pulmo where the fish are protected. Okay.
Sharks are worth a hell of a lot more alive than dead. Palau is a tiny little country with some of the most beautiful seascapes in the world, and dive tourism is almost 40 percent of the gross domestic product of that country. So they did a study, and some Australians came in and helped them with it, and they figured out that economically, in terms of people who came to Palau to do nothing but to dive with sharks—which is a questionable desire, but there are people who like to do it—and it turned out that a shark was worth $1.9 million in its lifetime in terms of what people were willing to pay for the thrill of diving with them. A dead shark was worth $108 for the fins and the meat. That’s a more than 17,000-fold difference.
Well, this has really caught on. Northern Australia has a $25 million-a-year business, which is exploding, to go dive with sharks on the Great Barrier Reef. Fiji is in on it, Malaysia. And in the United States, people are now wanting to go diving with sharks. Although we’ve done a really good job of pretty much eliminating them in U.S. waters.
We are among the worst of all the American countries. Our track record is like an F-minus in terms of coral reef conservation. Jamaica is doing better, and they’re poor and they’re hungry. Anyway…and that’s sort of like whales, right? People pay a lot of money to be in a boat and to be as far as I am from you who is nodding, from a gigantic whale. It’s a thrill. It’s really cool. And it’s a basis of economy.
The sea urchins are coming back. We don’t fully understand why, but my wife wrote this great paper about something called the Allee effect, which is, these kinds of animals don’t copulate. They just throw out their sperm and they throw out their eggs, and if they meet, then they make a baby, and they have a chance, a one-in-a-million chance of growing into a sea urchin.
So if there’s one sea urchin over here, Mary, and there’s another one, John, over there, the chances of their egg and sperm actually ever getting together are almost zero. And so you have to get over this hill, this critical density, and it seems like that’s happening.
So look at the picture on the left, 1999. What you see is a forest of algae and one dead Acropora palmata, Elkhorn coral. Two years later, the algae are completely gone. The sea urchins are all over the place, and little baby corals are growing and collecting everywhere. So it’s very cool, actually.
The other organisms that play a major role in getting rid of algae on seaweeds are parrotfish. This exquisite thing is a spotlight parrotfish, it’s like this. And you can hear them eating because they like to eat cement, and they come and they eat the algae on the cement and they go, crunch, crunch, crunch. And when they swim away, they poop sand. And so if you have a school of 50 of these fish, you see almost simultaneous pooping of sand as they swim off in the distance.
But the point is, where you gotta love this parrotfish—and those aren’t even parrotfish above; those are trigger fish. But where you have a lot of parrotfish—that’s a picture in Curacao very recently—coral reefs look great. Where you gill net them and they’re the kind of stuff in the bottom, you have no coral. You have nothing but seaweed. Duh, right? Okay.
Now, this is an amazing story. This guy named Nick Graham, diving in the central Pacific—you know, these are good jobs we’ve got. You get to do stuff like that. And he was working in the central Pacific and he realized that when he went to islands that were infested by rats, there were no seabirds and the coral reefs looked awful and there were very few fish.
But when he went to islands that had no rats, either because they got rid of them or they just never got there, there were tons of birds. And of course, the birds feed all over in the ocean. They come back, they poop, and some of that goes into the water and it gives nutrients, and there’s much higher productivity.
These connections are amazing. Who would have thought that coral reef health depended on whether or not an island was rat-infested? These are the kinds of complex interactions we’re discovering. But we can fix it. They’re getting rid of the goats in the Galapagos; we can get rid of rats. New York can’t, but on an island, you can. Okay.
This is an example that my wife gave me. So, Tampa Bay is a place that for some reason I’ve never understood, people like to go. And it’s the largest embayment in Florida. It’s gigantic. And it used to be covered all along the shores by this seagrass you see.
But they didn’t do a lot about their sewage, and as the population grew from 100,000 to half a million to a million to 2 million, and the bay got loaded with nitrogen, and I already told you about dead zones, the seagrass died. And you see the algal slime that replaced it, and it stank. And that was really not good for property values and all the rest. And actually, that stuff is sort of toxic and not good for your health at all.
So they decided to do something. And this podium is in the way, but in the 1980s when there was practically no seagrass left, they got their act together. And the town and the counties and everything cleaned up sewage treatment and they did everything they were supposed to do. And there is now as much seagrass in Tampa Bay as there was in 1950 before the problem began. We can do this in New York Harbor.
Okay, the last point I want to make, and I think fundamentally it’s the most important thing, and especially like this wonderful audience of you all here, you’re here I think because you care about science and you care about the environment. There is a quiet revolution happening in terms of the public understanding of the extraordinary beauty and complexity and just phenomenal aspects of ocean life.
So I want to close by saying it’s easy to say the government has to solve this for me, right? It’s the government’s job. We need more regulation. We need better laws. That ain’t gonna do it.
If everybody here in this room doesn’t change their habits, if you don’t stop consuming all the crap you consume, if we don’t abolish Walmarts—who needs, what, 90 percent of what’s in a Walmart? And that’s our whole balance of payments mess and all the rest of it.
We have to fundamentally change the way we live. We have to think about whether we should eat meat. We have to think about whether or not we should drive a gasoline car. You realize that if nobody bought a new gasoline car after today—they kept their cars as long as they want, but the next car they bought was an electric car—something like 40 percent of our total emissions would disappear. Okay? And it’s a very simple thing to do.
So please go away thinking about, there’s all this bad news, there’s this good news. But it’s really, really up to you. There’s no easy way out of this. We need to undergo a profound cultural change. Thank you very much.
The worlds’ oceans are under tremendous threat from a variety of human actions. But marine ecologist Jeremy Jackson doesn’t think it’s game over yet. After a decades-long career studying factors damaging our oceans—seaweed overgrowth in coral reefs, pollution, disease, climate change—Jackson hopes to find effective scientific solutions to save the world’s largest ecosystem.
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