The Slippery Slope to Slime or A Mutiny for the Bounty?
January 18, 2008 | Jane Lubchenco dives into the choices society has when it comes to saving our oceans and the critically important role of science in exploring what options are available.
I'd like to welcome you to this joint Wrigley Seminar. It's my distinct honor to introduce to you Dr. Jane Lubchenco, who is a distinguished professor of zoology. Please welcome with me Dr. Jane Lubchenco.
Thanks Susanne. Thanks very much for the opportunity to be here. I've had a really wonderful set of interactions just in the last couple of days with lots of students and faculty. It's been a lot of fun. You guys have some great things happening here, and I hope you all kind of appreciate and take advantage of the great diversity of programs and people and interests that are here.
There's clearly a lot of energy, a lot of good things happening. So congratulations to those of you that are working to make that happen. And thanks again for the opportunity to be here.
I want to spend my time with you to focus on some global patterns that are happening in oceans. And I chose a title that though, a little bit on the long side, I hope to be a little bit provocative. And you can see, I'm suggesting that society has some choices in terms of the future of the oceans. And the choice I'm framing as the slippery slope to slime, which whose meaning should become obvious as I'm talking, versus a mutiny for the bounty.
I think that these are very real and important choices that society is unaware are being made, and that scientific information has a critically important role in helping to have people understand what's happening, what's driving the changes, what the choices are, and what the options are. So that's pretty much a broad overview of what I'm going to be focusing on. I'm going to do that by organizing my remarks in three sections. I want to begin by focusing on a little bit about the interaction between science and society so that you know where I'm coming from when I talk about all this stuff. I'm going to talk about global changes in oceans, and then some of the options that are out there.
If you go ask members of Congress why they fund science, what good is science? Why should they fund it? Why should the country invest in science? And it doesn't have to be the US. It might be any country.
The kinds of answers that you get are generally in one of these categories. Most often, members of Congress focus immediately on health, because they're feeling their own mortality and their own bodies doing weird things. And so they're really concerned about funding for NIH. And that clearly is an important thing for science to discover, to push the boundaries of knowledge in ways that also create benefit for society.
But there are other labor saving devices, communications, discoveries, all of our communications, IT changes that have revolutionized the world have come out of very fundamental advances in science. Not always engineered to have a particular outcome-- the science for just blue sky create curiosity driven research is very important, but it often has feedbacks to society. And those have been used as good reasons to fund science.
Science as an engine for economic growth has also been touted by many politicians as important. We saw that initially in the IT revolution, more recently in nanotechnology, other areas. Science to enhance, national prestige. Countries brag about how many Nobel prizes they have or which country is the first to do X, put a man on the moon, or whatever it is. National defense has become a lot more important in this country since 9/11 with a lot of scientific efforts re-diverted.
These are all important, but I think that it misses an area that I think is critically important, and that is simply science to help us understand how our world works, how it's changing, and what our choices are. I think the role of science to inform our understanding is critically important and hasn't received the credit that is due to it, and is a very valid reason for funding a lot of science. And I choose this term informing judiciously, because I don't think that science should dictate what society does. But decisions will be better if they have scientific information that has fed into those decisions, decisions that are based on science, that incorporate that science. Even though there are a variety of other factors that go into a decision, politics, economics, values are critically important-- but the science should be at the table as well.
And I would suggest to you that that kind of scientific information could be organized in a number of different categories, how does our world work? And our world might be natural systems, social systems, or coupled human natural systems. How are those things changing? How is the temperature of the Earth changing? How is the nitrogen cycle different from what it used to be?
So how are things changing through time, documenting those changes? So we have some objective record that we can look to instead of just my opinion that it's changing versus your opinion, and a bunch of assertions. We need some information. So this is what monitoring is all about and is important.
But more than just those two things, looking ahead to the future. Given how these systems work, given our understanding of them, given the changes that are happening, what is likely down the road? What are the likely future states, given a business as usual scenario? And what are our options for alternate pathways? Are there different possible futures?
And what are the tradeoffs? If we want a different future, how do we get there? So these are all the kinds of things that I include in this science to inform category that I believe is part of our social responsibility to help society understand these things that we know and study, but framed in a way that is useful to them.
Now if decisions are to be informed by science, then the people who are making those decisions, whether they're your parents, your siblings, your children, or whether they're institutions-- and that might be a business, it might be a church, it might be Congress, it might be the state legislature-- all of those decision makers need to have access to information that is relevant to the decisions that they're making, and they can understand that's timely and credible. I think that, especially for environmental issues, that's a really tall order. That's not an easy thing to do. The science is indeed complex. It's nuanced.
We use a lot of jargon terms. We talk about probabilities and uncertainties because they're very real. However, I think that despite the fact that it's complicated, if we don't figure out how to communicate what's known in ways that are understandable and relevant, then we get what we've seen play out a lot over the last decade or so-- and actually earlier that-- it's nothing new-- vested interests will ignore or cherry pick or spin the data for their own means.
And so I think that the result of that is the decisions are made without good science and science is seen as a weapon. And you have dueling scientists that are framed as he said, she said kinds of things. And I think this is really a bad situation.
So to help get us to a point where I think we should be, and are in some quarters, it's really important to clarify the role of science that it should be informing not dictating, and to train scientists to communicate much more effectively, and to create mechanisms to synthesize, integrate, share the information, but translate it into ways that are relevant to policy and relevant to the kinds of decisions that people are making. Now there are mechanisms for doing some of these things. Scientific assessments or one of those. The Intergovernmental Panel on Climate Change is one example of a mechanism.
The Millennium Ecosystem Assessment is another international scientific assessment that takes the science, publish in the peer reviewed literature, but says what of this information is relevant to policy decisions? So we need more mechanisms like this. And they don't have to be just at the international level.
They can be at the local level. But they need to be ones that are relevant to the decisions people are making and are done with credible people in a credible process. So when I talk about the science of global changes in oceans, this is information that's to give you a sense of how I see the interaction between scientists and society in making choices about oceans.
So I'm going to segue now to a focus that's more ocean specific, and consider some of the changes that are happening in oceans to give you a sense of what's going on at the global scale. But I want to be very careful in focusing not just on some of the very real challenges that are out there, but some of the hopeful signs that there can be a different trajectory than what we see many places. I'm going to draw heavily on the results from the Millennium Ecosystem Assessment, which had a couple of chapters on oceans and coasts, status and trends, evaluating what do we know about what's happening. It wasn't a complete synthesis of everything we know about oceans, but there's a lot of that that's available as well in the literature. But the parts of the Millennium Ecosystem Assessment are directly relevant to this, and it was a recent synthesis.
The global pattern for oceans is pretty dire. In general, there are two major conclusions about what's happening to ocean ecosystems. One is that they are being depleted and disrupted. And the second major conclusion is that they are increasingly likely to undergo very rapid change. And in many cases, that's collapse of an ecosystem.
And that's couched as loss of resilience to maintain the normal suite of goods and services that are typically provided by a particular ecosystem. So that's the bottom line. What's the information for it? And what are the causes that are thought to be driving those changes?
The causes are clearly multiple. And these play out differently different parts of the world. Some of these are more important than others.
Overfishing, use of destructive fishing gear have been a very serious problem all over the world. It's being addressed in some places in some good ways. So it's not that everything is bad about fishing. But the global pattern has not been very good. Pollution from land, especially nutrient pollution, in particular, fertilizers used for agricultural purposes ending up in coastal waters causing very significant changes in those coastal waters.
But coastal development turns out to be a major cause of many of the changes that are happening in oceans around the world. You know how explosively Phoenix metropolitan area is growing. The same thing is happening for most coastlines around the world. They're just growing explosively. And that coastal development is having very real consequences to coastal ecosystems.
Climate change and ocean acidification are also critically important. Now we don't have time to go into all of those. So I'm going to focus just on overfishing and destructive fishing, because that is a very pervasive influence pretty much every place in the oceans, and is one for which we have a fair amount of information. But I don't want you to think that this is the only challenge that's out there.
It's fair to say that fishing practices have changed dramatically, especially with modern technology. Some of those changes are much for the better. Fishing is a much safer enterprise than it used to be. It's much more economically efficient. It's much more targeted.
But it's also the case that we can fish farther and farther from shore because we have refrigeration, we have much better ways of navigating. We fish deeper and deeper, and in many cases, much more destructively than we did and in places that were in accessible earlier.
I'm going to show you an animation that was prepared for the Millennium Ecosystem Assessment by a team of folks at University of British Columbia with Daniel Paulie. This is an animation that takes the data from FAO, the UN Food and Agricultural Organization. All the countries report data to FAO on an annual basis. What are your catches? And they've taken these data and organized them.
So this is an animation that shows year by year by year. So we start with 1951. And you watch this counter. And it'll count through year by year until we get to 1999.
And you will see on here white ocean every place, which is pretty peak. And then red is where the harvests are the highest, where the greatest amount of fish are being caught. And then when it's no longer economically viable to fish there at that intensive rate, the fishing enterprise moves elsewhere. And left behind is the pink, so it's post-peak.
So the pink in some cases, are places that have been completely denuded and may never recover, or they have been seriously overfished and might recover, or it's just economically feasible to fish someplace else. So the pink is a little hard to judge exactly what that means. So the pattern here to pay attention to is just sort of the global picture. I'm going to start the animation. You can see the counter is going.
Pick some coastline some place, and follow what happens. And the general pattern is that we are fishing farther and farther away from the coast and farther and farther south. We're up to 1985, 1995, 1999. We're pretty much fishing every place.
I'll let it run once again. Look at a different spot. I think it's pretty obvious that there are very few places that were not fishing in the oceans.
Now in addition to fishing farther and farther away from the coasts, we're also fishing deeper and deeper. And here are the data showing that. This is average depth in meters through time starting in 1950. And the average depth of fish catches is deeper and deeper. And modern technology has enabled that.
New discoveries of deep sea populations, orange roughy off New Zealand, Patagonian toothfish in the southern ocean. So this pattern is pretty obvious. In the whole history of fishing has been one of pretty much sequential depletion.
One stock is overfished, and then the fishery moves on to another stock that's newly discovered someplace else, whether it's deeper or farther away. And we've run out of new stocks to exploit pretty much. And so that's partly why the patterns are what they are.
These are the global patterns of fisheries. This is a total catch per year, million metric tons starting in 1970. And the peak fishing globally, the total amount of catch reached a peak in the 19-mid-‘80s and has been on the decline since then. So this is what the global picture of fish catches looks like.
Global fisheries peaked and are now declining. According to FAO, 25% of global fisheries are very significantly depleted now. And that number was zero in 1950. So the percentage of fish in different categories, how the UN evaluates how much it's overfished has been changing very dramatically. And it's mostly in the last couple of decades.
And a paper published in Nature on 2003 provides some very compelling evidence that about 90% of the great big huge fish of the oceans are gone, the tuna, swordfish, marlin, sharks, the great big huge icons are no longer in those oceans. 90% of them have been removed by industrial scale fishing. We've just gotten so good at catching them, there are just not that many left.
So the patterns of global fishing are quite significant. You see all these historic photos of the good old days with huge fishes. And it's just not like that anymore.
This is the auction that happens every morning in Tsukiji in Tokyo. The fish market. The largest fish market in the world. These are bluefin tuna that are up for auction. And the price of them has just skyrocketed.
Guess what the most expensive bluefin tuna-- single tuna-- has been auctioned off for? Just wild guesses. $1,000? $50,000? $40,000?
How much? Half a million. So a couple of years ago, one fish went for $75,000. Last year, one went for $125,000. One fish.
I once was on a plane to a scientific Congress in Japan. And I was upgraded to first class. And the guy sitting next to me had this box in a seat. So he had two seats that he had paid tickets for. He was a fisherman from Spain.
And on the seat was his fish that he was taking. And it wasn't worth it to him economically, to fly first class-- two first class seats, because he knew he could get this much money. The economics of this are insane.
And this is part of the problem. Now I love bluefin tuna. I don't need it anymore. But I would like to be able to have a world where I could eat it and feel good about it. And so I think these are complex issues.
This is another figure from the UBC group that shows the North Atlantic. So here we have the Eastern seaboard, Europe. And this is the biomass of table fish in different categories, tons per square kilometer, color coded. So these were very, very productive waters. And this was in 1900.
And we're going to fast forward to 2000. So 100 years ahead. And you can see how drastically different the catches of table fish were then versus now. And you can pretty much have data like this from any place in the world and it's the same picture.
The other thing that it's happening is crashes of mini fisheries that are very, very abrupt crashes. This is one of the best well known. This is Newfoundland cod. But many of the fisheries along the west coast-- the rock fish populations have done very similar things-- lots of other fish populations.
So these are catches. And all of a sudden, what looked to be a fantastic fishery, all of a sudden there is not much there to catch. So very, very rapid change in a very short period of time.
There are empty nets that fishermen are coming up with, many places around the world. Not every place. There's still a lot of fish that's being caught. But the small scale fisheries and the local just go out and catch your dinner to feed your family kind of fisheries, are the ones that are really in serious trouble because of these patterns. And when you consider that over a billion people a year depend on seafood for their primary or sole source of protein, it gives you some sense of some of the human dimensions the consequences of these problems.
Now it's not just the total amount of biomass that we're taking out of oceans, it's also whom is being removed. And I flagged the big fish problem. And there are a couple of places around the world where we can get an insight into what the trophic consequences of current fishing practices are likely to be by having some insight into comparisons of places that are lightly fished versus places that are heavily fished. And these data come from the Hawaiian Islands. The main Hawaiian Islands are fairly heavily fished and have been for some time.
The Northwest Hawaiian Islands-- and this was pre the establishment of the Northwest Hawaiian Islands new National Marine monument it is. And before that monument was established, these are lightly fished just because they're so far away. Nobody lives here and so you have to transit long time. So these researchers did a comparison of what does the biomass of different groups of fishes look like on the main islands versus the Northwest Islands, and what does the trophic composition look like? Let's look first at fish biomass.
This is the main Hawaiian Islands, and this is the Northwest islands. And you can just see there's a lot more stuff, a lot more biomass there. But more interesting, is how the trophic breakdown-- whoops-- what it looks like. Well, I went ahead, but that's OK.
So if we look at the Northwest Islands, over half of the predators are considered apex predators. In that area that's heavily fished, it's just a little tiny sliver, because that's what fishing has targeted. So it's removed all those. And so we now have mostly herbivores, about half of the biomass, whereas before they were about 27%. Low level carnivores 18, and about half here.
So there had been very dramatic changes in these areas, likely as a result of fishing. And it's reasonable to think that many similar things have happened in other communities where top predators have been removed.
Daniel Pauley has created this figure to sort of describe trophic position on this axis through time. And so this is a cartoon that represents that there used to be a lot of big fishes, high trophic level large bodied fishes, and that we are now in the process of fishing down the food web, fishing at lower and lower trophic levels. And there in fact are good data to support that. And this is a cartoon representation of the actual data.
But the removal of the top predators is apparently causing significant changes in many of those ecosystems. And it's not just the removal of predators, but there are other things going on, that there is less biomass, there is some types of fishing create a lot of habitat destruction, and there are other confounding factors as well. So there are multiple drivers. But one of the consequences of this appears to be what we're seeing many places around the world, which is increasing outbreaks of pests or pathogens. And exactly what the causative agents are is not always clear, because there are a lot of different things that are happening.
But there is a global pattern of more and more, what Jeremy calls, slime. And Jeremy Jackson has coined this term. He says we're on the slippery slope to slime, which is pretty dramatic. But in fact, what we are seeing are many increases in outbreaks of jellies many places around the world. This whole fishing net is just chockablock full of jellies.
Here are coral diseases. So there are increases in both of those. And there are more and more places around the world that are being taken over by ephemeral weedy algae and bacteria pretty much eliminating lots of other species. And so this is the slime that appears to be characteristic of a number of especially coastal ecosystems that have been heavily overfished and have nutrients coming in, sediment coming in from the land, other things happening.
So from a scientific perspective, slime is not a very scientific term. And we can't connect the dots between all of these different changes that are happening. But it is pretty clear that more and more ecosystems, especially coastal ones, are seriously degraded. And so framing it as a slippery slope to slime is not very scientific, but in fact, is a description of what is happening a lot of places.
It's pretty easy to identify the biological causes of a lot of these changes. Setting aside the social, political, economic drivers, the biological causes, the rates of fishing are greater than the rates of replenishment. That's pretty much a no brainer. That's pretty obvious. There are cumulative and interactive interactions between fishing and a lot of these other changes that are going on.
There are ecosystem impacts of fishing. Removing those top predators can cause other changes in the system. Habitat destruction, bycatch species, interactions are complicating the picture. So it's not just overfishing. It's often the ecological consequences of who's fished and how they are fished.
And the fact that fishing targets what biologists are starting to call the boss, the big old fat female fish. And this is sort of a new buzzword among a lot of the fishery biologists, because turns out that these boss are pretty important because they represent most of the reproductive potential in the population, and by selectively eliminating them, that has consequences to the population as well as social dynamics and social structure.
More recently folks have been focusing attention on the evolutionary consequences of fishing. And this is something that has come to light only very recently. And I want to say a little more about that because I think it's probably really important.
Marissa Baskett, who is a graduate student at Princeton, now a postdoc at NCEAS, has been working on this and doing some very nice modeling. And David Conover, who's at SUNY Stony Brook has also been working on this topic, and they both are coming to many of the same conclusions that if you have a system that's not fished, it has a lot of big bodied individuals. After fishing, you have much smaller bodied individuals. And Marissa has been particularly interested in how the fact removing the big bodied ones, what consequences that has on the life history characteristics of the populations.
And she has done a number of models trying to explore some of what's happening. How much selection has to happen? What's feasible over a certain period of time? And the bottom line is that by continually removing the big bodied individuals, you are ending up with populations where fishes are reproducing at smaller sizes.
And that's partly a function of the trade-offs between growth rates, size, and age. And so you have smaller fishes that are reproducing earlier in life. And that reduces biomass yield. It's complicated by the fact also that the number of young that are produced have this kind of relationship with the size of the fish. And so there's reduced reproductive output, which feeds back to reducing biomass yield and sustainability even further.
And so this combination of factors appears to be theoretically possible. And in fact, there is evidence for this happening both in the lab and in the field. David Conover had Atlantic silversides in lab situations where he has actually demonstrated that they, through time, just by removing the larger individual in the population, you get selection for reproduction at smaller sizes. And Marissa has compiled a lot of literature from economically important species, for which there is a rich amount of fishery information, suggesting that, in fact, there is evidence that the same thing has happened in all of those populations. So it looks as though the picture that's emerging is that the depletion that's happening and the disruption of systems is likely a consequence of both ecological as well as evolutionary changes.
And so the question is what's down the road? What is the future of our oceans look like, given that the pathway we're on seems to be not one that's to many people's liking? Whether you're a fisherman or a fish lover or a wild animal lover or just like to enjoy swimming or scuba diving or whatever?
So what are some of the underlying problems? How might they be addressed? What are some of the options? And again, I'm framing this as choices. And I think that's a useful way to think about them.
The US recently had two commissions, the Pew Oceans Commission and the US Commission on Ocean Policy. Each of which were charged with evaluating what's happening in US waters, and what kinds of options, policy options might be implemented for different things to happen. The Peel Commission, both commissions went all around the US and talked to lots of communities of people, and asked them what's happening in your neck of the woods, your section of the coast. What's good? What's bad?
And one thing that we often ask them is what do you want from oceans? How do you see oceans? What do they provide to you? And this is the list of things that I heard people, Americans say they wanted from oceans. And it depends on who you were talking to, but healthy seafood, clean beaches, stable fisheries, abundant wildlife, vibrant coastal communities are the kinds of things that people say they want.
Now I would suggest to you that in fact, these are ecosystem services. Most of the people who were telling us these things never heard of ecosystem services. They don't know that language. It's not couched as regulating services or cultural services or supporting services or what have you, but these are services.
These are benefits that people get from the oceans. And it's in their language. And these are the things that they want. And this is what is at risk and what is being threatened, because of many different current practices and policies in oceans, as well as on the land. So the two commissions made a lot of recommendations about what could be done to change this.
The fisheries' problems that were identified were a number that are pretty obvious, effort in size controls, don't take into account ecosystem evolutionary impacts, enforcement is insufficient, there aren't any mechanisms for really protecting these boss, there aren't mechanisms for protecting habitats, there are very few incentives for fishermen to conserve. The economics of fishing favors short term, very intense exploitation. And there aren't in most fisheries the kinds of mechanisms to encourage fishermen to save something for the future.
The solutions that are proposed by the commissions are multiple. They are a tall order when taken as a package, but in fact they are not impossible. They're quite doable. That doesn't mean they're easy. And many of these are being actively considered by members of both state and federal organizations that are trying to address these issues.
I want to focus just on one of them though, on networks of no take areas, marine protected areas because I think they offer many tremendous benefits in conjunction with a lot of these other solutions, and for which there is a lot of new scientific information that's really relevant to the kinds of things we've been talking about. Marine reserves are areas of the ocean that are no take. They are completely protected from extractive or destructive activities on a permanent basis, except as is needed to monitor or evaluate them. So marine reserves are a special category of marine protected areas, which is a much larger set of areas that are managed for some conservation goal, but might exclude just one type of fishing. Or they might allow all fishing, and they exclude drilling for gas or oil.
So MPAs, marine protected areas is the larger category, but it is pretty ill-defined as to what is allowed or not allowed. Marine reserves are much more specific, they're much more limited. You can't take something out of them. You can't drill for gas or oil, you can't fish, you can't dump stuff into it.
Until very recently the ocean was replete with de facto marine reserves, just because there were so many places where you couldn't fish. It was too far away. It was too deep. It was too rocky.
And as you saw in that animation, we've pretty much eliminated all those places, and everything is accessible. So it's useful to sort of keep this in mind because folks that are talking about creating networks of marine reserves are sort of re-establishing what used to be there, as opposed to doing something that is completely novel.
Callum Roberts created this figure to sort of encapsulate the information about how much of the ocean is protected. He took all of the marine protected areas in the world, calculated the area, pulled it all together, and just plunked it off the coast of Africa here. So this yellow is the sum total of all of the MPA in the entire world, but just all put together. And this little red dot is the sum total of all of the marine reserves in the world. So even though there are thousands and thousands of MPAs and reserves, few reserves, hundreds of reserves, they're tiny, they're teensy.
And most of the ocean is not protected. That's surprising to a lot of people. A lot of polls that have censused Americans on how much of the US waters do you think is protected? People typically say a third more or less. And they are really surprised and sometimes even angry to see how little is actually protected in this way of protection.
We recently-- and over the years-- initially through an NCEAS working group that Leah was part of, compiled all of the science that has been published in their peer reviewed literature about marine reserves and produced a synthesis of that information in language that was deemed to be accessible and understandable to lay audiences, and published a science and marine research booklet in 2002. That booklet has been so useful, we haven't been able to keep enough copies. We just keep having to reprint more. And the science has just skyrocketed. There are now some 300 new papers on marine reserves since we did the first booklet.
So we've recently redone the entire analyzes, recompiled all of the information using the same kinds of guidelines that the IPCC and the MA did. So we're using only information that's in the peer reviewed literature to include in this synthesis as a way of giving it credibility. So this is the new science and marine reserves booklet that's just out.
It's available for download from this website or you can request copies. So we had a large number of authors from many different countries, a ton of reviewers. And the information that's in here, again, is sort of a synthesis of the science.
These are the marine reserves around the world that have been studied by scientists with publications in the peer reviewed literature, so you can go to those papers and say what happens when you create a marine reserve? What have we learned about what changes when you establish one? And that's what we asked. So this gives you a sense of where those are. And the bottom line is that when you set up a marine reserve in general, things change dramatically inside that marine reserve.
So these this is percent change in some biological measure, biomass density, size, diversity. The dots are the raw data. So each one of those dots is a different marine reserve, some place. And the histograms show you the mean values. And you guys will appreciate this.
We had endless arguments about whether we should do means or medians, because to us, we would like to see medians. We'd like to see range, standard deviation, some indication of variance. For most people for whom this booklet was designed, It doesn't mean anything to them. And it makes them not even want to look at it. And so in the end, we sort of bit the bullet and said OK, we're going to do averages, even though we're more interested in medians.
At any rate, on average, you get an increase in biomass of 446% when you set up a marine reserve. There are huge increases in density as well. There are significant increases in size and in diversity, with some places doing a lot, lot more, a lot greater increases. Some places having negative numbers. In most of the cases of the negative numbers, this is a situation where inner reserve herbivores were really abundant because the predators were fished.
You set up a reserve, you're no longer fishing the predators, predators become much more abundant, and their prey becomes less abundant. So of course that's going to go down. So a lot of these changes reflect sort of reestablishing a lot of the ecological dynamics that would be typical of unfished places, but that are not typical of fished places. So in reserves by and large, things happen.
This is percent change of the same axes. Percent change in biological measures. This is for biomass, and this is for density. And this is comparing the tropical sites-- the tropical in yellow to the temperate in blue. And a lot of people in temperate areas were suggesting that reserves weren't needed in temperate areas, and that most of the results were distorted by what's happening in the tropics.
Well, that's not true. These are not statistically different. If anything, there may be slightly stronger results in temperate areas, but they're pretty much effective both places is the bottom line there.
It's definitely the case, not surprising, different species respond at different rates. Some increase really rapidly early on. Others take a much longer time.
These are data from Tim McClanahan studies in Kenya. Varied some of the longest reserves, the oldest reserves in the world where something like parrotfish in blue, increased very rapidly and then have leveled off. Surgeon fish, on the other hand, recovered relatively slowly, and are continuing to increase even after 40 years. So not all species respond at the same rate. That's not at all surprising.
What about what happens outside a reserve? It's clear that inside a reserve there is very significant conservation benefit, protecting biodiversity, protecting habitats. But a lot of folks are interested in spillover in benefit to the outside.
These are data from fishes that were tagged inside a reserve and have been caught by fishermen outside a reserve. So it is evidence of spillover. And these are distances that the fish were caught away from the reserve from different parts of the world. So it's pretty clear from these and other data that there is a lot of spillover.
Things are getting big inside, they're getting crowded, and they swim out. And so that there is benefit to the immediate area outside. That's not likely to influence a very large area. It's going to be mostly right in the vicinity.
The other potential impact of reserves, outside of reserves is through the exports of larvae. And this is where these boss become really important. Because of this size fecundity relationship, there is huge potential for export if you let fish get big. And this is a comparison of three sizes of rockfish. But I want to focus your attention on this is a 14.6, 15-inch rockfish.
Each one of these little icons stands for 100,000 young. So this rockfish produces 150,000 young. If this rockfish grows to this size, 24 inches instead of 15 inches, then she would produce 1.7 million young. Now that relationship is not at all surprising to biologists. But it blows most lay people's minds to really appreciate that getting a little bit longer mean a lot more young.
Now not all of these young are going to survive. But the chances, if you have 150,000 versus 1.7 million, there's a lot more chance for these young to be being transported by ocean currents outside the reserve and receding areas outside. So their models are pretty convincing, showing the benefits of reserves to fisheries.
The evidence for this happening is much harder to come by. So there is empirical evidence, to sum up all of this, that reserves protect habitat, species and ecosystems. They provide spillover of juveniles and adults.
They can protect these boss. They can restore species interactions. There is modeling results that are pretty convincing that larval export has huge potential to affect some fisheries and that they can provide insurance. Experience suggests that reserves can also provide a scientific reference area, some area against which to evaluate the efficacy of various fishery management practices. We don't have any controls. So these are controls. And provide recreational value and educational value.
So there are a whole suite of things that reserves can do. Thinking about them as single units used to be the state of the art. The current thinking is now about networks, about networks of reserves, which can at least, have the potential to have both fishery and conservation benefit. And so instead of thinking of a single large piece, you have the same area, but in smaller pieces that have leakier edges. And the idea here is to have solutions that are designed in a way to maintain connectivity, have larvae be produced in one and land in others, and have a safe place to grow up, and they can be connected by the movement of juveniles and adults as well. There are a number of places in the world now where networks have been consciously designed with using scientific design ideas to create new ways of protecting and restoring ecosystems, Florida Keys South Africa, Channel Islands, Great Barrier Reef, Marine Park Authority. A third of the Great Barrier Reef Marine Park Authority is now a network of no take areas.
The Australians have really embraced this concept, in part because they've seen the benefit of reserves. They initially had only 1% in reserves, and then 5%. And they saw so much benefit to that, that they've now gone to having a fully a third of the area.
Now despite all of these, the area that's in reserves globally is still just a drop in the bucket. But there is a lot of momentum in this area. There's also a lot of controversy.
It's not surprising that people who use oceans, fishermen in particular, recreational as well as commercial fishermen would not believe someone saying you're going to benefit if you give something up. And they are giving something up. And that benefit is probably displaced in time. They're not going to see an immediate benefit. And many of them are convinced that they're not part of the problem.
So there are some real interesting social dialogues that are happening around this concept. Much of the science that has been informing this is not just what happens when you create a reserve, but what do we know about species that will enable us to design reserves better. And the size and spacing guidelines that are now being developed for the California process that is playing out, there's a law in California, the Marine Life Protection Act that mandates creations of networks of reserves up and down the coast. And so scientists have been trained in this process to help design these.
And the information has drawn on information about movement of adults and movement of larvae to help guide the thinking about how far apart should they be, and how large should they be. The how large should they be is a function of movement, in adult movement, where you have a lot of different species, some of which move very little, others move some, and others move a huge amount. If you have a single reserve or a single reserve even in a network, the size of that reserve is important, because if the reserve is a kilometer long, then these kinds of species will be relatively well protected within it. But something that typically moves 100 kilometers, it's not going to influence that one at all. And so the smaller the reserve, the fewer number of species are going to be predicted in their adult phase.
And so you can play with different sizes of reserves a reserve that's 10 kilometers long is going to protect these species, but not these. One that is 20 kilometers is going to protect something that's a little bit more. So you can play with the size of the reserves. And you can also play with the distances between them by using information from larval dispersal.
This is estimated dispersal distance that is from the literature, based on genetic information, primarily. And we know that for seaweeds, invertebrates, and fishes, these are the dispersal distances that are typical for many species around the world. And it doesn't matter from one place to another. It's pretty much similar pattern.
So you can do the same thing and say if reserves are 10 kilometers apart, then these species could go be produced in one and land in another. But species that disperse shorter distances probably wouldn't be protected. So you can play with the sizing and spacing guidelines and see what the trade-offs are in protecting different kinds of species.
So in California, for example, they suggested that sizes be a minimum of 5 to 10 kilometers, and that the preferred size was 10 to 20 kilometers. And for spacing, that the recommendation was reserves be spaced 50 to 100 kilometers apart. So this is an example of how information about these species is being used, sort of as we speak, in the creation of guidelines that now citizens are using to propose different configurations of reserves in a network that are then evaluated for how well they meet these guidelines. So the scientists in this process aren't choosing which reserves or which package of networks. They're not saying where to draw the lines.
They're providing the guidelines. And then citizens groups are proposing where they think a network would fit these guidelines and would be socially acceptable to them. So fishermen are actively engaged in this process and saying well, this is my favorite place.
Let's not put one there. But let's put one here. And if you combine the size and spacing information with habitat kind of information, so that you are trying to include different types of habitats and have a representative area, a network, then you can have a process that actually uses the scientific information, but in a way that the science is informing the decisions.
And finally just on the evolutionary note, because I introduced that concept earlier with Marissa Baskett's work, she has done some modeling looking at networks of reserves, such as the one that's around the Channel Islands now. This is Channel Islands off California. And these are the no-take areas in this network. And she has created models that contain strong selection outside the reserve.
So this is size selection. Weak selection inside the reserve, and exchange between inside and outside. And what she has shown is that even when you have weak selection inside the reserves, you can, in fact, have reserves serve to counter the selective pressures for evolutionary changes in life history characteristics like size. So that's a pretty interesting finding.
So the conclusion here is that marine reserves, the information that we're gathering, suggests that marine reserves can provide very powerful tools. And in some cases, they're unique for some of the benefits that they provide. They're not a panacea. They don't do everything to fix oceans. So they really have to be coupled with other kinds of tools, good fishery management, tools such as dedicated access privileges or other kinds of tools that might provide fishermen with an incentive to have something to fish down the road, so incentives for conservation, pollution controls, consumer awareness, lots of other tools.
For those of you that don't live right next to an ocean, some of this may be a little farther afield. But the way that most people connect with oceans is in fact, through seafood. And in fact, if these are issues that you care about and want to be able to eat fish, eat seafood, and not feel guilty about it, one way that you can do that is to educate yourself about what kinds of seafood are caught in ways that are sustainable or are farmed in ways that are sustainable.
And this seafood watch card is one of the tools that's out there. This particular one is provided by the Monterey Bay Aquarium. Environmental Defense also has a seafood card. Blue Ocean Institute does. And elsewhere in the world, and increasingly in the US, the Marine Stewardship Council is certifying fishing practices.
And so you can end up with information that is easy to carry in your wallet or your pocket, and to look and see is this seafood something that's sustainably caught or farmed or not? So there have been a lot of campaigns by a lot of NGOs to educate people about seafood choices. And a whole group, the Seafood Choices Alliance, is providing information not just to consumers, but to chefs. And there are a lot of celebrity chefs that are interested in promoting this. So there's a lot of increasing awareness around the issues of food.
So to sum up, I've emphasized that I think a key role of science is to inform choices of society. And that means helping to understand what's happening, what's causing it, and what the options are, and what the trade-offs are. That there are very significant, very serious global changes happening in oceans. And that the overall pattern is one that is not pretty much in the right direction. And that we really are at a crossroads where there are different choices that are available to society.
And I framed them in this sort of hokey slippery slope to slime versus mutiny for the bounty. But in fact, I think those represent very real choices. And there is a wealth of information that is available for most of the stuff that I've been talking about.
But the bottom message that I want to leave you with is not only the importance of the science in this social dialogue about what our future looks like, whether it's on oceans and land or in our communities, but also one of urgency, that things are pretty serious and are changing rapidly. But also that there is hope, that there are some very good tools. There are people that are interested in doing things and making a difference, and that it's not a situation where you should throw up your hands and just say can't do anything about it.
There actually are good things. And scientists are needed now more than ever before to help provide information about the urgency and about the hope. Thank you very much.
Did everybody hear the question? Is restoration a viable tool to help jump-start some of the networks, especially for those species that don't disperse very far like the invertebrates and especially the seaweeds? Tools for restoration are not very well developed for most marine systems. It would be a huge benefit if we had the ability to do more of that.
People are really trying to figure out how to do that with corals, for example. And there have been some successes. I think that that is an area that hasn't gotten a lot of attention, and that could be very usefully explored. If we could jump-start some of these areas, that would actually be really useful.
The surprising things to many people who have studied reserves is that even areas that were completely trashed, and people thought there was nothing there, so they didn't object to the creation of a reserve, have been blown away by the fact that stuff came back in it. And it's clearly coming from someplace. How far, we don't always know.
But it does seem to be the case that many places around the world, simply creating a reserve, is going to bring benefit. That doesn't mean it wouldn't happen faster with some kind of proactive restoration seeding efforts. But even without that, things are happening.
Did everybody hear that question? If you guys want me to repeat questions, I will. If you don't, then you can pose them louder. You want to do that? Why don't you stand up?
I think the best thing to do is to have more scientists be voices, number one. And to have mechanisms for enabling scientists to work through what some of the differences are. Sometimes there are very legitimate differences of opinion, and it's not something for which there is consensus. Other times, there is a very strong consensus, but it's not getting expressed because there are few loudmouths each side, and people don't know how to sort out where the bulk of opinion is.
And so I think the best tool in something like that is a scientific assessment that can be done by a credible organization. And that's what the IPCC has done or the MA, but it doesn't have to be international. It doesn't have to be every six years. It can have some other kinds of assessments. The university can do assessments or somebody else.
Even when there isn't a formal assessment, a tool that has been used are consensus statements. And so you can have a group of scientists sort of work through how we actually get a word, what it is that we agree on, and then sign it and release it. And that can be very helpful. I think that parallel efforts though, are in educating more people about the issues, and about what the evidence is.
One reason that we did this science and marine reserves booklet is that this was such a hot topic in California at the time, and there was a lot of confusion about it. And there were a lot of assertions about what reserves could do, what they couldn't do. And a lot of the assertions were just wrong about what they could do and what they couldn't do. And so we said OK, let's be helpful to this process and pull this information together so it's credible, but also take the time to create graphics that are user friendly, sort of USA Today kind of graphics where you'd look at it and you get it. That's what people need.
They're not scientists. They don't know how to interpret mediums. They don't know what variances. And to use language that's not jargon language. And so that booklet is an example of a way to educate people about the issues.
And now more and more people know about this issue. There still are areas where there are disagreements. And some of those are legitimate and some of those are just hype, some hired gun that's been hired by somebody who doesn't like the process, that's causing trouble, that just has no credibility.
Sometimes they're very credible scientists who in some cases don't know the same information. So part of the process in California has been to bring all those voices together in the science advisory team. And the current science advisory team has people who have very vocally disagreed with the earlier decisions, and are in the process of exploring the models and understanding. And they're actually coming around to agree with a lot of the earlier findings and recommendations. So it's partly a process of educating within the scientific community.
So I think all those elements are important, educating the public, educating the decision makers, providing information, not just to the public and the decision makers, but to other scientists. We often think that other scientists know what we do and they read all the papers we do. And that's not always the case.
So, the folks who are working on aquaculture issues definitely do that, because aquaculture, because it is mariculture. It's farming salmon. It's also farming Tilapia. It's farming trout.
And I think the issues there, you highlighted a really important one, actually a couple of them, one is the trophic position that the fish is. Tilapia is much lower than salmon. And also, what are the feeds? And for farmed salmon, they are fed fish meal that comes from small pelagic fishes, sardines, anchovies, anchovettas. And the conversion ratios, it takes about two to five pounds of wild caught fish to grow one pound of salmon.
So a lot of people think that by eating farmed salmon, they're actually relieving pressure on wild-caught fisheries. And that's not at all the case. It's actually contributing to the demise of ocean ecosystems because the harvest of these small pelagics, which provide food for the higher trophic level fishes, but also marine mammals, marine birds, all sorts of other things--
So there's a lot of talk now in the aquaculture industry prompted not within the industry, but from outsiders who drew attention to some of these issues, about how to make those conversion ratios better, and how to figure out how to use something other than wild small pelagic fishes to grow farm fish. But feeding on catfish or Tilapia or carp in general, is much better than feeding on wild salmon.
And shrimp are also fed fish meal. They don't have to be. Shrimp are omnivores, and they can be grown in ways that are much more sustainable. But it's a lot easier to just throw a bunch of fish pellets into a shrimp pond.
And there's increasing interest in growing more shrimp as a cash export crop, without looking at the consequences either to ecosystems or anything else. It's just sort of, let's make as much as we can. So in those situations there are many better practices and policies that could be adopted to make farming of shrimp more sustainable.
There's not much reward for doing that economically right now. And there's no demand that it be done most places. So aquaculture is really in transition. I think we're really going to win the early stages of a Blue Revolution that's not unlike the Green Revolution where there's just an explosion of aquaculture. There's no doubt in my mind that it's going to be really important for the future.
But the kind of aquaculture that is growing the fastest is the salmon and shrimp, and in addition to salmon, other high trophic level species. And so that's not food for the masses. It's what's called in the industry the white table cloth market. It's food for yuppies. It's food that we all enjoy and we like.
If you eat seafood, salmon and shrimp are good. We, in Oregon, are really lucky, because we can get wild salmon, which I think is much better. But there are a lot of issues.
And the seafood watch card of the aquarium and the other card-- if you go to their website, they actually talk about a lot of these trade. So there's more information if you're interested in what some of those trade-offs are, and why something is ranked with a green light or a yellow light or red light, which is to be avoided. But there are a lot of trade-offs in those.
We unfortunately have a break here. Jane is scheduled for a podcast with Peggy. Join with me thanking her for this wonderful presentation. Thanks very much.
Thank you all very much.
This presentation is brought to you by Arizona State University's Julie Ann Wrigley Global Institute of Sustainability, for educational and non-commercial use only.