Book World Live

Callum Roberts and Alan Weisman
Author, "The Unnatural History of the Sea;" author of "The World Without Us"
Tuesday, July 31, 2007; 12:00 PM

In this special eco double feature, Callum Roberts, author of "The Unnatural History of the Sea," and Alan Weisman, author of "The World Without Us," field questions and comments about their work and the endangered state of our planet.

Read Jonathan Yardley's review of "The Unnatural History of the Sea" and "Lonely Planet", the review of "The World Without Us," which both appeared in the July 29 issue of Book World.

Alan Weisman is a senior radio producer for Homelands Productions and is Laureate Associate Professor in Journalism and Latin American Studies at the University of Arizona.

Callum Roberts is a professor of marine conservation at the University of York in York, England.


Alan Weisman: Hello -- Alan Weisman here, author of The World Without Us. It's a book that theoretically wipes humans off the face of the Earth, to let us see more clearly what else is here and how it might proceed without our daily pressures -- albeit some of those pressures would take a while to play themselves out. My hope is that this perspective will ultimately cause us to wonder how we might have a refreshed and largely restored ecosystem whose healing didn't depend on our untimely demise -- how can we add ourselves back into the picture, yet in a more reasonable balance with everything else alive.


Callum Roberts: Thanks for this opportunity to talk about recovering ocean wildlife and fisheries. I look forward to answering your questions.

Best wishes, Callum.


Washington, D.C.: Professor Roberts, I'm curious about the research you did for the book. What sort of sources did you use to paint such a complex picture of the past? And how long did the research process take before you began writing?

Callum Roberts: That's a very good question. When I thought of the idea for the book in 2001, I expected it to take a couple of years to research and write. But the more I read, the more I realized I needed to know, so the more I read. In the end, it took five years. In that time, I read an awful lot of old books and reports, many bought from Ebay (you'd be amazed what you can find). So many people today believe that because a document is old, it is out of date and not worth reading. But I found out so much by reading history, including of course that there is nothing new under the sun. Many of the problems we see in the oceans today were recognized 100 years ago, as were many of the solutions. The difference is that there was so much more in the sea then, and people felt they didn't need to act, but could just fish somewhere else or for something else. We no longer have that choice. Today, we must act to bring depleted species back, because we have nearly run out of alternatives (unless you like jellyfish).


San Antonio, Texas: Reviewer Grunwald wrote the following in Sunday's Washington Post about your book, Mr. Weisman:

"Even as a thought experiment, a one-child policy is a terrible idea, a draconian one-size-fits-all solution to a variety of complex problems. (In America, for starters, our problem is overconsumption, not overpopulation.) It's also exactly the kind of nature-first idea that makes environmentalism so threatening to so many people. Humanity's goal should be to limit our impact on the Earth, not to limit our presence on Earth. We don't have to do it for the Earth's sake; we should do it for our own sake. It's our home."

You took exception to this paragraph on the radio yesterday, Mr. Weisman. It begs the question of how do you prevent a technologically advanced and highly populated society -- ours -- from over-consuming, from using more than its share of the world's resources? Which is the better idea and most workable solution -- lessening birth rates, or the rate of consumption, or possibly both? Lonely Planet (Post, July 29)

Alan Weisman: It's pretty clear in my book that I favor doing everything possible to mitigate overwhelming human pressures on the rest of nature. So I don't see any conflict between limiting consumption and limiting the number of consumers -- they go hand in hand. I knew in advance that I would touch some people's sensitive spots by bringing up the population issue, but I did so because it's been missing too long from the discussion of how we must deal with the situation our economic and demographic growth have driven us too. I was surprised to see that the reviewer cast it as a matter of not-this-but-that, because he wrote a valuable book about the Everglades and it's inconceivable to think that the population explosion of Florida has had nothing to do with the stresses we've put on the Everglades. The bottom line is that any species that overstretches its resource base suffers a population crash. Limiting our reproduction would be damn hard, but limiting our consumptive instincts may be even harder. Meanwhile, if we don't take control of this situation, nature will do it for us, and it won't be pretty.


Washington, D.C.: Prof. Roberts -- I work for Oceana, an international environmental group dedicated to the restoration and protection of our oceans. Like you, we believe that it's not too late to save the oceans. We have our methods of outreach, but I'm curious to know what you think needs to be done to ensure the viability of our oceans for generations to come. Thank you!

Callum Roberts: I wrote this book as one response to that question. Scientists spend much of their time talking to each other and the messages from their research take a long time to filter through to the general public or those who need to act on the findings. The field of historical ecology is somewhat specialized but learning about history has immense popular appeal. In the book, I wanted to breathe new life into the oceans of old by revealing them through the eyes of people who witnessed their untrammeled bounty. I hope that these visions will inspire people to fight for the resurrection of these ecosystems by working to recover at least some of what has been lost. I think old photographs of the size of past catches (both numbers of fish and the sizes of animals caught) have the power to astonish us and capture the imagination. We need to use them much more in communicating what has happened to the sea and what we must do to bring marine life back.


Freising, Germany: Callum Roberts mentions that the Marine reserves, places that are protected from all fishing, have had notable success in giving endangered species breathing room.

But in the article, "Fate of the Oceanin Mother Jones Magazine, Julia Whitty writes,

"Among the most frightening news for coral reefs is the increasing acidity of the ocean as a result of rising levels of carbon dioxide. Scientists at the National Oceanic and Atmospheric Administration recently estimated the ocean has absorbed 118 billion metric tons of CO2 since the onset of the Industrial Revolution-about half of the total we've released into the atmosphere-with 20 to 25 million more tons being added daily. This mitigation of CO2 is good for our atmosphere but bad for our ocean, since it changes the pH. Studies indicate that the shells and skeletons possessed by everything from reef-building corals to mollusks to plankton begin to dissolve within 48 hours of exposure to the acidity expected in the ocean by 2050.

Coral reefs, buffeted by so many stressors, will almost certainly disappear. But the loss of plankton is even more worrisome".

I'm a big supporter of Marine Reserves, but global warming and the associated increased acidification of the oceans could render such Marine Reserves as insufficient to save marine wildlife, don't you think?

A question for Alan Weisman: If mankind disappeared overnight and carbon dioxide was no longer dispersed into the atmosphere, how long would it take for the carbon dioxide levels in the atmosphere and oceans to return to pre-industrial revolution levels?

Callum Roberts: I agree that the sea is subject to many stresses, and increasing seawater acidity is one very worrying effect of rising atmospheric CO2 levels. We still don't know exactly what kind of effects raised seawater acidity will have on marine life, but we do know that over-fishing is reducing populations of many species in the sea to dangerously low levels. We need to act now on threats we do know about, rather than saying that some new threat in the future might render today's efforts void. So marine reserves are very important, and they could also increase resilience to global climate change. Intact, healthy ecosystems will have a much better chance of weathering climate change than damaged ones.

Alan Weisman: According to scientists I've interviewed, to reach pre-industrial levels will require about 100,000 years. However, possibly 80 percent would be re-absorbed in the first 1,000 years, which is about the time it takes for the oceans to turn over. The other carbon absorbers are plants, of course, and, at a grander pace, rocks -- e.g., rain with dissolved carbon dioxide reacts on rocks as carbonic acid, dissolving soils and minerals that eventually precipitate out as seashells, etc. If we stopped sending buried carbon skyward tomorrow, the seas would absorb all they could hold over the first few hundred years, then when saturated water is replaced by water welling up from below, the process would continue.


Washington, D.C.: I've spent my life primarily on the East Coast, from Key West to Cape Cod. I have memories from childhood and a little beyond, spanning from the mid-1960s through the 1980s of abundant catches of enormous fish as large as or double the size of the fishermen. I remember seeing a tarpon while scuba diving during the 1980s that was six or eight feet long. Is it true that if I were to go diving today, that there is a slim-to-none chance that I would see anything like that now?

Callum Roberts: It depends where you go. There are still places where you can encounter giant fish, but sadly there are far fewer of them today than in the 1960s. In the 1960s there were far fewer than in the 1860s. You can still see remarkable fish in places that receive little fishing. Palmyra Atoll in the mid-Pacific, for example, still has fish populations much the same as when was when it was discovered in 1798. (The sharks are a bit smaller thanks to a short spell of long-line fishing a decade or two ago). But the best places to go to see big fish are long-established, well-protected marine reserves. Today, almost all of the oceans above 2000m deep are fished. In this new phase of human relations with the sea, the only refuges that exist where fish can grow big and old are those that we deliberately create. Go to a good marine reserve and enjoy the spectacle. Some of the marine reserve zones on Australia's Great Barrier Reef are marvelous, and so are many of the reserves in Palau and New Zealand, for example.


Ontario, Canada: We restock lakes with fish.

Why is it that we don't bother restocking the ocean?

Could we hatch fish (creating jobs for out-of-work fishermen) and set them free into the ocean and expect them to grow?

Callum Roberts: Restocking depleted fish populations is something people have been doing for over 100 years, in freshwaters mainly. The idea is that because survival of very young fish is so low, getting them past this early stage could increase populations. Sadly, like many technical solutions, the ocean is just too big for restocking programs to have much of an impact. I tried releasing a bunch of hatchery-raised Nassau groupers off the U.S. Virgin Islands a few years ago. Several hung around the release point for months until they grew emaciated, and several were eaten almost straight away. Captive reared groupers didn't seem to have the survival instinct of wild fish.


Charleston, S.C.: Which countries are doing the most to create marine protected areas? Is the U.S. involved?

Callum Roberts: Many nations have begun to establish networks of marine protected areas, but so far, not a lot of it is protected from enough fishing to help some of the most vulnerable species. That said, South Africa has stated that it will set-aside 20% of its waters in marine reserves. Palau and a number of other Micronesian nations are on course to protect 30% of their waters. The United States is picking up steam. The California Marine Life Protection Act has recently created a network of marine protected areas and reserves in State waters. The Northwest Hawaiian Islands National Monument was recently signed into law and is the largest marine protected area in the world. To my knowledge, 95% of its area will be protected from all fishing within five years. A great start but much more to do in other parts of the U.S.


Detroit, Mich: Weisman suggests in an NPR interview that we should reduce the population. That seems like a very scary proposition. Who is to decide what kind of people do we have an excess of? China's one child policy has created horrible effects in that society.

Alan Weisman: I begin this book with a theoretically possible but unlikely fantasy -- that all humans somehow disappear tomorrow -- and end it with another: that starting tomorrow, all families limit themselves to one child. My intention was just to run the numbers to see what would happen, which proved very interesting: within a century, attrition would bring our numbers back down to pre-1900 levels, around 1.6 billion. Contrast that with today's 6.6 billion, or 2050's projected 9 billion,and you get the picture. The prospective, which I describe as draconian, would be democratic, because it would apply to all, rich or poor, developed or undeveloped (whatever "developed" means). The Chinese experiment showed us the pitfalls and problems of such a plan. Are we ready to re-address it, as we now finally seem ready to talk seriously about global warming? I don't minimize in my book that this could be a severe measure -- I wouldn't have been born, because my sister came first, etc. But we are facing severe decisions to keep our world livable: we lack technologies to provide enough clean, abundant, cheap energy to meet our skyrocketing demand, and to my observation we also lack the collective will to curb our acquisitive desires. Population control should be part of the mix that we consider, because if we don't take careful measures curb our numbers, nature will surely do it for us. Arguments that we can produce enough food to feed all nine billion humans make no sense: the ecological cost of the way we produce that food even today are already undermining our natural foundation.


Washington, D.C.: Mr. Roberts: I was taken aback by how the descriptions of the devastating effect of trawling from many decades ago are still accurate -- to those of us new to the plight of the ocean it's a bit disheartening to see that the problems (and solutions) have been around for so long. Do you see anything special about this point in history to fuel optimism about humanity's relationship with the sea?

Callum Roberts: What I see that makes me optimistic is that the needs of industry and conservation are aligned. In many parts of the world fisheries are in crisis because the animals that we catch have not been sufficiently protected. Conservation of stocks is a fundamental of healthy fisheries. We have only recently realized (how could we miss it for so long?!) that fish need healthy habitats in which to grow and breed. So ocean protection and conservation are essential to the continuation of fishing.

Seventeen years ago, when I first started work on marine reserves, many people poo- poo'ed the idea of protecting areas from all fishing as silly. Today, marine reserves are being discussed at the highest level of government in the United Nations. That is encouraging. But we all need to add our voices to the call for a more sensible approach to the way we use and enjoy the sea.


Lakewood, Colo.: Are there any fish we should avoid eating to help the oceans?

Callum Roberts: There are lots of fish that you should avoid eating on ethical grounds. Patagonian toothfish, orange roughy, North Sea cod, many kinds of tuna... the list is a long one. To help navigate these difficult choices, check out the web for guides to ethical seafood consumption. The Monterey Bay Aquarium, and Audubon Society in the U.S. have handy pocket guides as to what is good and what to avoid that can be downloaded from their Web sites. In the U.K., the Marine Conservation Society does something similar for European fish.


Troy, NY: Mr. Weisman: I just read your book and was so utterly depressed by it that I didn't want to get out of bed. How did you find the fortitude to continue writing it to the end?

Alan Weisman: I'm sorry, even surprised that depression was your response, because many find the book strangely uplifting: at the very worst, even if we vanish, I show how resilient life itself is, and that it will go on: it's been through worse extinctions than the one we're currently perpetrating before, and will recover again. I know it's sad to think of us disappearing -- this book doesn't merely dwell on the alarming things we've done, like create more radioactive waste and plastic than we know what to do with -- but also some of our wonderful things, like our art and music and spiritual expressions. Ultimately, of course, every species does go extinct, just as every individual ultimately dies. What kept me going through my research was the belief that, although we've made some bad messes, a combination of nature's remarkable propensity to heal and our best efforts to contaminate less, use energy far more judiciously, creative some imaginative technologies we haven't even dreamed of yet that mimic instead of subduing nature, and limit our numbers could help preserve our rightful place in an ecosystem we've worked damn hard to evolve into. I'm not ready to give up on us yet. A Toronto newspaper called this book "the very DNA of hope" and I guess that's the way I emerged from writing it: comforted by life's limitless creative ways of springing back, even in the most unlikely settings, and flourishing. I hope we get to participate.


Washington D.C.: Dear Dr. Roberts,

A perception of crisis is often needed for people to act and/or change behaviours. What marine crisis do you think will force people into action at a scale needed to change the current trends in the marine environment?

Callum Roberts: I think the marine crisis is already upon us and in many parts of the world we have only a decade to get protection in place before some of the losses sustained become irrevocable. There are few fully marine species that have yet gone extinct due to human pressures (that we know of, there could be many more among small and easily overlooked species). People in many developed countries emptied their seas of many of the most desirable species long ago. We can only continue buying great seafood in the shops because it is being imported from developing countries. When they run out, we all run out. It won't be many more years before this happens, because fishers are mining fish, rather than harvesting them, from the waters of many developing countries. To me, that is crisis enough to be calling for action loud and long.


Fairfax, Va.: Mr. Weisman, it seems that help with the environment needs to come from not only the individual but on a bigger scale by the government? Is the present administration doing enough to not only encourage individuals but also big business and other polluters? What do you see happening?

Alan Weisman: The answers to our current challenges will have to come on every level -- individual, national, global. Our current administration in the United States clearly has other priorities: I'm not going to go into detail, because other journalists report new examples daily. I'm encouraged on two levels to see what former politician Al Gore is doing today: first because he's helping bring widespread national attention to issues despite concerted efforts by politicians and business to discredit them, and second because during the Clinton-Gore administration far too much attention was devoted to economic growth and far too little to the inevitable downside of it. I'm glad to see him back on track, since he truly understands these issues, and if he had to leave politics to do so, that tells us something important. Despite my book's title, "The World Without Us," it's filled with interesting people who help hold the planet together, from brave scientists to the unsung heroes who maintain our infrastructure lest it all crumble -- which, as I also show, it would, with surprising efficiency. I have no politicians or even policy makers in the book, which may lead some to conclude that they may be more expendable than they believe. We certainly need some new, imaginative ones. And fast.


Washington, D.C.: Why do you think most marine protected areas fail or are at least "paper parks" and what does this say about MPAs as tools for conservation?

Callum Roberts: I think there is a false perception that signing something into law means that it happens. Marine protected areas, like those on land, that are declared and then not protected are worse than useless. They give the impression that something is being done when it is not. I think what we must do is to look at the successes and learn from them. And then we must raise the standards of all protected areas towards their level. Great protected areas can be found where communities have committed to protect their natural resources and have pursued that goal with conviction and tenacity.


Silver Spring, Md.: Professor Roberts,

It is wonderful to hear that you have been able to take some very complicated scientific data and present that in a way that is so digestible and easy to understand. Are there specific recommendations you would make to your colleagues in the scientific community to help them ensure that their research is communicated effectively and therefore relevant in the minds of policy makers and the public?

Thanks for your commitment to saving three quarters of our planet!

Callum Roberts: There is almost always a local angle to every piece of science. Too often the places where scientists do their work see nothing of the results, which are published in technical journals and talked about at distant meetings. I would like to see more scientists take their findings back to the local level and work with people there to put them to use.

At the other end of the spectrum, many local stories have wider lessons for society. It is important to try to bring those lessons to a wide audience who can gain from the insights they offer. Great organizations like Seaweb have been helping scientists get their stories out to the public and decision makers for years. We need more like them, because scientists are not always natural communicators.


Ontario, Canada : Thanks for answering my question on restocking the oceans.

Your Grouper experience shows we are doing it wrong, but does not show it cannot be done. The problem is obviously more complex. Perhaps things like adding a predator to the tank of hatching, and making the fish hunt for food sources may be necessary. ...

But is there any other solution to depleted ocean fish stocks?

Callum Roberts: The best solution to depleted fish stocks in my view is to establish large scale networks of marine reserves where nature can do its own restocking. The benefits will spill over into fisheries as animals move from protected areas into surrounding fishing grounds, and as large, protected fish produce lots more young that will repopulate those fishing grounds. Reserves are not enough on their own, however. We need to bring fishing effort down to sensible levels in surrounding areas; we need to eliminate the most destructive fishing gears; and we need to apply the best available technologies to avoid harmful bycatch and habitat damage; and we need to use more of what we catch.


San Francisco: Dear Mr. Weisman,

In your book, I understand that you propose that each woman capable of having a baby only have one. It's a different way of looking at resources -- instead of trying to stretch and economize, we could just lower the number of people. However, I feel like this is not a feasible solution; how many people would agree to that? What is something I can do as an individual that will make a difference? A world without us may be better or worse, but we're here nonetheless.

Alan Weisman: I'm replying to a few questioners together. I've already answered the population question -- yes, lowering birthrates will be hard, but somebody tell me what would be any easier. We have to meet the challenge on as many fronts as possible. One thing you can do is ask your legislators to make it a crime for supermarkets to offer bags for free. The real answer to "paper or plastic?" is: neither. Your grandmother went to market pre World War II with the same bag, over and over. Plastic bags didn't exist then, so she threw the carrots and bananas and onions all together -- and, amazingly, their flavors didn't mix. We did fine before plastic bags, and we'll do fine without them: they add nothing to our lives except for more plastic. If you do use one, get one durable enough that it can be reused indefinitely, because of microbes have evolved yet to eat plastic: it took millions of years for them just to figure out how to digest lignin and cellulose, which is why we have a Carboniferous layer of coal metamorphosed from undecayed trees. I have a plastic shopping bag I bought in a Mexican market 30 years ago that still works beautifully, over and over. (And paper, by the way, just sits in our landfills, not decomposing if it's buried away from oxygen. To the greatest extent possible, leave it in the trees where it belongs.)


Tallahassee, Fla.: What about nutrient loading into our near shore waters from poorly treated storm and wastewater? The Florida Keys reefs and all of Florida's near shore waters seem a lot greener and less diverse lately.

Callum Roberts: Coastal pollution is a real problem as human population densities rise. If we are serious about keeping oceans and their wildlife in good shape then we need to treat more of our waste and better before discharging it into the sea. Storm events will always be a problem as they tend to overwhelm treatment works. Having more animals around to consume plankton and seaweed will help avoid the greening of reefs that is happening across the world, not just in Florida. Overfishing can exacerbate pollution problems because it reduces populations of consumers. Rebuilding populations of fish and other animals will help combat pollution, but we need to do much more to avoid releasing pollutants in the first place.


Mesa, Ariz.: I'm astounded that people at this point in time still argue that overpopulation is not the problem. Many more species will go extinct as our population rises.

Alan Weisman: Me, too. I'm even more astounded that your state, Arizona, is running out of water faster than nearly any place on Earth, and yet it's our fastest growing state. Look, I wasn't such a hot math student, either. But the basic arithmetic is all we need to see that some numbers just plain don't add up. Fact is, we've been doing things this way all our lives, so it's hard to accept that they won't keep working for us at some point. Look around the Phoenix area: the Hohokam paleo-Indians built elegant canals to channel the Salt River into an area that could sustain a large population. That worked until drought undermined that plan, and they vanished. What makes us think that this can't happen again? Phoenix-area cities are now buying water from ranches hundreds of miles away, and pumping it uphill into a canal that stretches to the California border. You tell me how this can go on indefinitely, especially with exploding populations.


Washington, D.C.: What is the one thing I can do to help the oceans recover and if only I do it, is it still worth it?

Callum Roberts: Choose to eat only seafoods caught from sustainable sources using methods that don't harm other wildlife (see another of my answers for guides to what is good and what is not). Avoid a lot of farm-raised predatory fish like salmon because they get fed on wild-caught fish protein. And tell your friends about problems in the sea. The more people who know about what is going on, the better chance we have of seeing marine life come back.


Alan Weisman: Thanks to all readers for your questions. Each of them I read was important and urgent. I'm glad to be part of this conversation, because among us all some fresh perspectives might just bloom that will lead to some answers, and some agreement.

Alan Weisman

Author, "The World Without Us"


Callum Roberts: I just want to add that you can be a lover of seafood and a lover of the sea. Campaign for more marine reserves. They are good for fish and for those who catch and eat them.

Thanks for reading. Best wishes, Callum


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