Sala: Marine reserves can save oceans from humans

Marine ecologist Enric Sala explains the importance of mitigating human impact on marine environments Tuesday morning in the Amphitheater. Sala presented Chautauquans with a slideshow of the ocean’s most remote and untouched areas of marine life. Photo by Lauren Rock.

Laurence Léveille | Staff Writer

The ocean as shown by Jacques Cousteau was filled with life — coral, whales, dolphins, sharks.

But when Enric Sala tried to emulate Cousteau and explored Spain’s Mediterranean Coast, he found nothing of the sort. When he began studying marine biology and ecology, he met the same outcome.

“I thought that that richness and diversity Cousteau showed us was something that belonged only to exotic tropical locations,” said Sala, a marine ecologist, during Tuesday’s morning lecture in the Amphitheater.

He later learned humans were the reason why oceans looked different from what Cousteau showed.

As part of Week Four, themed “Water Matters,” Sala took audience members back 1,000 years to show them what pristine oceans look like and explained what can be done in the future.

Oceans, as people see them today, are lifeless. The bottom is covered by slime, and algae and bacteria outgrow corals. In comparison, pristine oceans have a diverse population of fish, predators, live coral and more.

Since 1950, 90 percent of predators have been removed from the ocean. One-third of fisheries have also collapsed, Sala said. If humans continue to fish at their current rate, all fisheries will collapse by 2050, he said.

“Not only are we taking the fish out of the water,” he said, “but also we destroy the seafloor by doing so.”

Sala wanted to reset his baseline of what the ocean should look like and decided to find out what it looked like a millenium ago.

He and a few others from National Geographic developed a project called Pristine Seas. The project’s goal was to find and explore uninhabited places and to help protect them. It was a way to understand what has been lost and what oceans were like in the past, Sala said.

Through their expeditions, the explorers found that humans have had an effect on the life in oceans, regardless of population sizes.

The expeditions began at an archipelago in the Pacific called the Line Islands. It was an uninhabited area unknown to others. The team knew it would witness a richer environment but had no idea what to expect.

“What we found really exceeded our expectations and blew our minds,” Sala said.

When he jumped into the water, he saw a vibrant reef, live coral everywhere and a diversity of large fish. Unlike the inhabited oceans, there was no algae or seaweed. Underneath the coral was pink crust, the preferred habitat for coral larvae to settle and grow, Sala said. Fish kept the rocks clean, and large predators, such as sharks and red snappers, lived nearby.

“If we traveled 1,000 years back in time with a time machine, and we were able to get out, take a photo and come back to the time machine, that would be it,” Sala said.

The moment led to Sala’s epiphany.

“After this, we felt like we could take entire chapters of marine ecology books and throw them to the trash bin,” he said, “because that understanding was based on the study of degraded ecosystems.”

The next question to answer was to see how a small population of people could affect the ocean. Sala and the others went to Easter Island, where about 5,000 people lived.

Although there were beautiful reefs with corals, Sala said, the area seemed lifeless. There were no large fish or predators. The team visited a pristine island, Sala y Gómez, about 200 miles east of Easter Island, to compare the two.

“It’s rocky, it doesn’t have fresh water, humans have never lived there,” Sala said. “For us, that was the perfect place to see the pristine equivalent of Easter Island.”

Once again, the ocean was filled with large fish, predators and lobsters one-third larger than the maximum size reported by scientists, Sala said.

Even when the team visited Pitcairn Island, which only had a population of 60 people, there were no sharks.

“When you jump in the water and you see sharks, you know that the place is healthy,” Sala said.

Predators are dominant in a healthy ocean. They have the most biomass, or pounds of fish per acre, followed by carnivores and then herbivores. But in a normal reef as people see, Sala said, herbivores have the most biomass, and predators have the least.

Only 5 percent of the ocean is healthy, he said, but protecting life via marine reserves can help replenish it. In five to 10 years, the number of species within reserves can increase by 20 percent and the size of those fish by one-third.

But only 1 percent of the ocean is protected, and the majority of these protected areas still allows fishing. Sala said scientists recommend that 20 percent of the ocean be protected.

Creating a network of reserves to accomplish that would cost $16 billion, compared with the $35 billion governments pay for subsidized fishing, Sala said.

While discussing marine reserves’ economic benefits, Sala compared the ocean to a savings account.

“The marine life continues increasing inside its boundaries, and it produces an interest that people can live off,” he said. “It produces a spillover that makes the fishermen better off.”

Species that go beyond marine reserves can boost profits due to spillovers. On the Columbretes Islands in Spain, 7 percent of lobsters migrate outside the reserves every year, Sala said. That means fishermen’s revenue increases by 10 percent every year. Marine reserves increase tourism, which in turn creates jobs, Sala said.

Sala ended the morning lecture by reminding the audience of the Earth’s finite resources. Though humans are capable of destroying those resources, he said, they are also capable of replenishing them.

“We have this amazing ingenuity, and we have this capacity of bringing things back,” he said, “and I hope that’s what we’re going to do in the future.”

Photo by Lauren Rock.


Editor’s note: This Q&A has been edited for clarity and length.

Q: I’m amazed at how sensitive these coral ecosystems are, where 50 people can destroy it, or 5,000 — why is that? Why are they so ultrasensitive to such a small number of humans, if that is the issue?

A: It’s because of two main things. People can pollute, but there’s not as much human population that does not pollute so much. The problem is overfishing. The first species that go away are the sharks and the large fish. Fishermen go after the larger fish, and these are the most long-lived and fragile. Those grey reef sharks that you saw on the photographs, they live 25 years, 30 years sometimes, but they don’t reproduce until age 7, and they produce only one to five pups per year. So you can see how difficult it is for this species to come back. Once we destroy the bottom of the food chain, all this imbalance starts to happen. And all the species that were eaten by the sharks now increase, and they eat other species lower in the food chain. If this species is lower in the food chain — are these sturgeon fish and parrotfish — that ideology that keeps the reef clean, what will happen? The seaweed will overgrow the corals and kill the corals, and there will be no chance for the coral to come back. And once the habitat for the coral is gone, there will be no habitat for the little fish that will become larger fish, so we’re getting in this vicious, negative loop. So that’s the problem. Removing just one important part of the ecosystem can have these effects in cascade, degrading the entire reef.

Q: Does the UN Law of the Sea Convention, if that’s what it’s called, protect marine life and diversity in your opinion?

A: Yes. OK, so, there are two oceans. The ocean owned by nations and the international waters. The ocean owned by nations is 200 miles from the shoreline. It’s called the exclusive economic zone of every country. The United States has exclusive economic zone that’s twice as large as its mainland. Pitcairn Islands have exclusive economic zone that is 50 times larger than the United Kingdom. And these areas are governed by the countries’ governments. The international waters belong to no one and belong to everyone, and they are governed by the UN Convention on the Law of the Sea. And it is very difficult to manage the high seas, because there is no enforcement, and it’s right now, basically a free-for-all; it’s a free-access area. And there are some clauses of the sea (law) that protect marine diversity and marine life. Unfortunately, they are so vague that they are not attached to any specific regulation, and they are never enforced. So right now, the Convention on the Law of the Sea is not being very effective. And the United States is one of only two countries that haven’t signed the Law of the Sea yet.

Q: Can you put things that threaten the ocean in a relative perspective? So if you look at things like fishing, offshore drilling, dumping waste into the sea — what are the most dangerous?

A: Historically, No. 1 is overfishing — still the biggest threat to the ocean. No. 2 is global warming. And then all the others come: pollution, invasion of species, etc. Overfishing removes all these large animals from the sea, which results in all these changes in the ecosystem, and then global warming is warming the water, killing coral reefs and making the water more acidic, which also will prevent the growth of every animal or plant that grows a shell or an exoskeleton.

Q: As a rising college student, how can I get involved with the efforts to create or support the reserves you were talking about? 

A: To date, marine reserves have been created by governments and government agencies — usually the department of fisheries or the department of the environment, and that involves dealing with Congress, and the Senate and lots of bureaucracy, and it’s impossible. And it takes so long to get anything done. Now, what we’re trying to do with this new program, we’re developing that we’re calling the fish banks, marine reserves — not as a sacrifice, not as a sink of public resources, but as a business opportunity. These fish banks are like a savings account, with all the economic benefits. So if you live in a coastal community, what you could do — and you would be a pioneer — is to rally your community around this idea and decide to protect one fraction of your coast. Develop a municipal entity that will have legislation passed to protect the area with the condition. The community will manage that reserve with private investment or a public-private partnership. So think of establishing a marine reserve as a business that is going to benefit your local community.

Q: Can you comment on the health of the Great Barrier Reef in Australia?

A: The health of the Great Barrier Reef of Australia. As you know, most of the Great Barrier Reef is protected by a very large marine park, and a third of that marine park is in no-take marine reserves. The Great Barrier Reef offshore is in pretty good shape. Inshore, it’s not doing so well, because there is a lot of runoff of sediment from upstream mainland activities, and warming is starting to have an effect on the corals — the radius of the Great Barrier Reef — where the corals bleach and die after very warm summers. The good news is that in these reserves that still have the sharks, and all the large fish and all the fish that eat the algae — these places are resilient. These places are like a machine with all its parts that can respond to global warming effects in the short term. We don’t know what’s going to happen with acidification. It’s a real mystery. We expect it to be catastrophic for coral reefs, and there are signs already on the GBR that show that maybe by 2050, the rate of coral growth will be slower than the rate of coral dissolution because of the extra acidity in the ocean. So the corals will be in recession, basically. Our only hope is these no-take reserves that still harbor the entire ecosystem that we hope will be able to balance itself.

Q: There are a bunch of questions here that are around the comment you made — 90 percent of large fish species have been depleted, or game fish, whatever that was, but there’s two questions here. Is it a demand issue, or is it a supply issue? We all like fish and we’re all eating more fish — is it something along the demand side, or is it the way we fish for the fish? The second question is, we all like fish, so there’s farm-raised, wild-caught, hook-caught, no-net — do you have any advice about what fish we should look for when we’re buying fish?

A: It’s all of the above. Demand and supply are tightly linked. In the real world, demand and supply doesn’t work like it does in economic textbooks, where the market is perfect and people are rational. You’ve heard about that before. The demand continues to increase, especially now that countries like China are increasing their average per capita income. And there is a strong correlation between per capita income and protein, animal protein consumed by humans. Chinese people right now have the largest footprint in the ocean, only because they are a lot of people. Their per capita footprint is very, very, very low because they eat mostly freshwater fish and fish that eat algae. The supply of wild fish is going down. The supply of farm fish is going up, and last year, for the first time in history, farm fish aquaculture produced the same amount of seafood as the wild fisheries of the world. Fisheries will continue to go down if we don’t change things dramatically. Aquaculture will go up, so aquaculture should be able to keep up with the demand, but we need to change also the way aquaculture is conducted, because in many cases, like for example the farm salmon — farm salmon are fed with fishmeal. And these are fish that are caught in the ocean with trawling — destroying the ocean bottom — then turned into a paste, then given to the salmon in farms. So it has ecological impacts, and energetically and economically, it is not very efficient. Now, the second question of the species you can eat or not. One thing I would recommend for everyone who is interested in helping from a personal point of view is to go online or have somebody go online for you and Google “seafood choice card.” There are a few organizations in the United States — like the Monterey Bay Aquarium, or the Blue Ocean Institute on the East Coast — that have produced these seafood choice cards, where you can see a list of the species to avoid because they are endangered or because the fishing method used to catch them is very destructive. And a list of the species that are still OK to eat. So this is something that every one of you can do individually and help.

Q: What exactly do rising temperatures mean for ocean life? What is the direct impact?

A: Most species have evolved to survive a range of temperatures. If it’s too warm, you have to move or die; if it’s too cold, you have to move away or die. This is why coral reefs, for example, are restricted to the tropics, because the average minimum temperature is about 20 degrees Celsius. You can’t find coral reefs in Alaska, you don’t have coral reefs in Antarctica, the same way these corals evolved to live with maximum temperatures. You know, the water didn’t get warmer than 30 degrees Celsius for more than a week in every year. But now, the warm events are increasing and they are lasting longer, so this species’ metabolism and physiologies are not used to coping with such warm temperatures. So they simply die. The animals, like the corals that cannot move, die. And species that can move will migrate. So the warm water is going to extend from the tropics to the temperate areas into the poles. The entire ocean is getting warmer. So those species that live in tropical areas when it gets too warm, they move to temperate areas. The problem is, right now, for the polar species, the species living on the North Pole or Antarctica — they have nowhere to go. They have no colder waters to go to. So there will be extinctions of the species on the Poles, and this affects the entire planet.

Q: There are a lot of questions on the Caribbean, maybe because a lot of us like to go to the Caribbean, but basically the questions are around the line that, from what you’ve shown, it’s a degraded area, not a pristine, obviously: Is there any hope for revitalization of the Caribbean?

A: Yes, there are a few no-take reserves in the Caribbean where the fish have come back spectacularly. Not only the large predators, such as the sharks, come back; the grouper comes back, the snappers come back, the sturgeon fish, the parrotfish. And one of the things that we found on these studies of pristine reefs that were so counterintuitive, is that when marine life recovers, when you have these reefs with lots of fish, you would expect that if the sharks come back, all of the fish below the sharks on the food chain will go down. What we’ve found is that protection basically erases all boats. There are more sharks, there are more grouper, there are more parrotfish, there are more sturgeon, there is more of everything. And in these places in the Caribbean that are well-protected, where we have all of the components of the ecosystem, including these large parrotfish, now we are seeing the parrotfish removing the seaweed and allowing the coral to come back. Now, these reserves work for most species, but some species respond faster than others. The fish that live five years will come back quickly. The groupers that live 20 years will take 30 or 40 years. For the corals, it may take many decades or a century, but we are starting to see the signs of the fish coming back, bringing back the rest of the ecosystem. So there is hope also for the Caribbean. The ocean of the future is not going to be like that pristine ocean that I showed you. It’s going to be a very different ocean. But we have the tools, especially these marine reserves, to bring back as much as we can, so we can continue eating fish out of the ocean and the ocean can continue provided all these goods and services that are so essential for our well-being. And again, this is not a sacrifice. This makes money from an economic point of view. So that’s my last message. I want to reiterate that this makes sense from every perspective.

—Transcribed by Leah Harrison