Counting and Improving Fish Populations
IRA FLATOW, host:
This is TALK OF THE NATION/SCIENCE FRIDAY. I am Ira Flatow.
This hour we're talking about fish and the dramatic decline in fish populations once thought to be inexhaustible. This hour there's some new research--some hopeful, some not so hopeful. But first, let's get right to the good news. This week scientists released a list of all the species identified in the Gulf of Maine. now that's a region of ocean stretching from Cape Cod to the Bay of Fundy, and this area is one of the most intensively studied parts of the ocean. Yet this week's sea census is the first scientific estimate of what species reside in the gulf and the results were surprising. The census revealed many more species--over a thousand more--than people had thought, once again showing just how little we know about what's living in the deep blue sea. Joining me to explain the results of the census and how the data might be applied to ocean management is Dr. Lew Incze. He's senior scientist at the bioscience research project at the University of Southern Maine and chief scientist of the Gulf of Maine Program of the Census of Marine Life. He joins us by phone from his office in Portland.
Welcome to the program.
Dr. LEWIS INCZE (Census of Marine Life): Hi. Thank you.
FLATOW: Hi. Is that surprising? So many--a thousand more species? Must be very surprising to you.
Dr. INCZE: It was a surprise. But the surprise comes from simply compiling the list. The list was put together by combing through all of the available databases and published papers to collect a list of all of the phytoplankton and the fish and the birds and the marine mammals found within the gulf. These aren't new discoveries. They're all things that already had been known, but no one had assembled an entire list of it. So that list is, in fact, quite a bit bigger than people had provided with an educated guess not too many years ago.
FLATOW: Can you put the results of the census in context for us? What does that mean if there are over a thousand more species than previously estimated?
Dr. INCZE: Well, that is still just scratching the surface of all of the biodiversity that's available in the Gulf of Maine, let alone the world's oceans. Most of these that are listed here are large or at least conspicuous--for instance, the phytoplankton are microscopic but they've been studied for a long period of time, and they have a great deal of diversity so there's been a lot of curiosity about them. There are probably thousands and possibly even tens of thousands of as yet unidentified taxa. One includes bacteria and viruses and other single-celled organisms that haven't received the same attention and a lot of very small invertebrates--by small here I mean about a millimeter in length--that live in the sediments in the ocean. So even that 3,300 and counting species--this is just a small fraction of the total diversity that we estimate is out there.
FLATOW: You know, those of us who are used to seeing the crystal-clear waters of the Caribbean and the fish that swim around there--when we think of Maine and the cold water we don't really think that there'd be a lot of living things in it.
Dr. INCZE: Well, that's correct, and that, in fact, provides just a clue as to the staggering amount of diversity that exists globally in the oceans.
FLATOW: Is this the first time the census has been done and the first census of its kind? Or are others going on?
Dr. INCZE: Well, it--our program here on the Gulf of Maine is just part of an international program to explore the biodiversity of the oceans and to understand, oh, the factors that affect those patterns of diversity, how those patterns change over time and how those patterns and change combine to form the unique characteristics of the different oceans and ocean ecosystems. There are a total of 14 field projects, each focused on a particular environment or a set of processes and technologies for studying biodiversity and we are just one of those programs.
FLATOW: 1 (800) 989-8255 is our number. Talking about fish populations this hour and focusing at the top of the program about the populations offshore in Maine. Has the Gulf of Maine census revealed any tricks, I might ask, to understanding patterns of biodiversity that you might apply to other parts or other oceans?
Dr. INCZE: Well, one of our tasks actually is to within a relatively modest-sized ecosystem--the Gulf of Maine is about 250 nautical miles across, approximately the same in the offshore direction--one of our tasks is in fact to establish methods that permit us to take a look at patterns of diversity in a coastal ecosystem. There are other projects that are looking at different types of scales and developing special technologies. Our challenge is to try to understand how these patterns actually contribute to the functioning of the Gulf of Maine ecosystem. So we have a special role within the larger program.
FLATOW: Is there...
Dr. INCZE: Tricks? No, I don't know. One of the tricks is simply finding enough funding to do all the necessary work, but there are several approaches that we are using to try to understand patterns. As I said, the amount of total diversity is just staggering, and it's not reasonable to think that we'll know all of those organisms anytime soon. So there must be sort of surrogates for trying to estimate what those patterns of diversity are, and one way is to look in different types of habitats and try to characterize how different undersea landscapes and undersea chemistries contribute to different patterns of diversity so that you can start to make a map of what the total diversity might look like.
FLATOW: Yeah, you mentioned that the numbers might go into the tens of thousands of different species, and that would include, as you say, the single-celled--not--you know, we might get the impression they're all big fish that you're talking about, but you're not. Most of them would be tiny little things.
Dr. INCZE: That's right.
FLATOW: Yeah, and...
Dr. INCZE: That's diversity. And in fact, this is one of the fascinating aspects of all this. There's a huge reservoir of information about life itself contained within all of these small organisms. And of practical concern, we don't know what properties of all of that diversity will really emerge as important to the system over long periods of time. So there's this aspect of both just curiosity and, I think, practical concerns about how we maintain the sustainability of systems and how we monitor their change.
FLATOW: Let's go to the phones, to Tina in Ayden, North Carolina. Hi, Tina.
TINA (Caller): Hi.
FLATOW: Hi there.
TINA: Thank you for taking my call.
FLATOW: Go ahead.
TINA: My question is what method was used to conduct the census? Like, what kind of netting or...
TINA: ...other procedures were used?
FLATOW: Dr. Incze?
Dr. INCZE: Yes. Well, I think the question has to do--there are two parts. One of them, I think, is just the number of species that are in the registry now, and that list itself was compiled by a search through databases and published papers. Depending on what type of organism you're talking about, the method of collection is very different. Sometimes water bottles; sometimes very fine mesh nets; and in the case of identifying whales and seals none of those apply: pairs of binoculars work pretty well. So it really depends what part of the animal and plant kingdom you're talking about here. With respect to the bacteria and viruses, this is all very new and very challenging because the diversity is really represented very largely at the genomic level, so it takes modern tools to try to assess what's going on there, and I'm no expert on that part of the diversity either.
FLATOW: Thanks for calling, Tina.
TINA: Thank you very much.
FLATOW: 1 (800) 989-8255. Let's go to Lex in McCall, Idaho. Hi, Lex.
LEX (Caller): Yeah, hi. How are you?
LEX: Good. You know, when I started listening I wasn't really quite sure. It sounded very exciting because the--it appeared that the gulf area had really seemed to be doing extremely well, but after listening a little bit it sounds a little more like they're still establishing more of a base line and I wasn't really quite sure whether or not things are really going well, or things are not going well with maybe some established findings that they've had previously.
FLATOW: Yeah, good question. I mean, you see all these species, but do you know if they're thriving or they're getting better or worse, Dr. Incze?
Dr. INCZE: Well, I mean, the Gulf of Maine has had its share of difficulties with some of the exploited fish populations, as other parts of the world have. The census effort here is trying to focus attention on those parts of the system that have been studied quite a bit less.
LEX: OK, great. Well, thank you.
FLATOW: Thank you. See if I can get a quick last call in here. Let's go to Julia in Philadelphia. Hi, Julia.
JULIA (Caller): Hi.
JULIA: Thanks for taking my call, and I love the good news about the diversity. My concern is what kinds of--were you able to test for any kinds of pollutants? We've heard a lot of talk about mercury in fish, and also since radioactivity is a global problem I was wondering if there was any indication of that in your study?
Dr. INCZE: Well, there are studies ongoing on some parts of that. Certainly the contamination which is mostly in, I think, freshwater and near-shore areas, but the census program itself is more focused on the diversity of life forms as opposed to some of the toxicological questions that I think you're asking about.
FLATOW: Thanks for calling, Julia. Well, in about the last minute we have, Dr. Incze, where do you go from here?
Dr. INCZE: Well, the database is only a beginning to all of this knowledge. Our focus is really on establishing what those patterns of biodiversity are that requires continued field work and then trying to understand how those patterns contribute to the function of the ecosystem as we know it. And this is really something where you bring in the scores and over hundreds of scientists in the area who've been studying various parts of the system. And then finally, how do we use this knowledge to improve the way we interact with that system, and that gets into the area that is referred to as ecosystem-based management. And it's relatively simply in its approaches--what you want to do in ecosystem-based management--but it's really difficult to know how we would put it into practice and so that's something that's going to take quite a bit of determination and several years of incremental learning and application.
FLATOW: Well, we thank you for taking time to talk with us today.
Dr. INCZE: It was my pleasure. Thanks for having me.
FLATOW: Good luck and have a good weekend. Dr. Lewis Incze is chief scientist of the Gulf of Maine Program and part of the Census of Marine Life. He's senior scientist at the Bioscience Research Institute at the University of Southern Maine in Portland.
We're going to take a short break and then move on to some more ocean surveys. This next one not so good, about the deep sea in the Atlantic. So stay with us. We'll be right back after this break.
I'm Ira Flatow. This is TALK OF THE NATION/SCIENCE FRIDAY from NPR News.
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FLATOW: You're listening to TALK OF THE NATION/SCIENCE FRIDAY. I am Ira Flatow.
We're talking about state of the oceans and the fish and things that live in them from the Gulf of Maine--now we're going to the northwest Atlantic off the Canadian coast. Researchers in Newfoundland have tracked the numbers of five deep-sea fish species, some commercially valuable, some snagged accidentally as bycatch. And what they found is nothing short of shocking: a drop in the number so far and so fast that these fish could be extinct within three generations. None of these fish is protected as an endangered species. The researchers report their findings in this week's issue of the journal Nature, and they join me today to discuss their study. And if you'd like to talk about it, our number is 1 (800) 989-8255; 1 (800) 989-TALK.
Jennifer Devine is a doctoral student at Memorial University in St. John's, Newfoundland. She joins me today by phone from her office there.
Welcome to the program.
Ms. JENNIFER DEVINE (Memorial University): Hi. Thank you.
FLATOW: Hi. Thank you. Richard Haedrich is emeritus professor of biology at Memorial University in St. John's. He joins me by phone from his office there.
Thank you for taking time to be with us today.
Professor RICHARD HAEDRICH (Memorial University): Yes. It's good to be with you.
FLATOW: Doesn't sound like, Richard--you're in Newfoundland. Your study looked at the fish communities in the northwest Atlantic. That's off the coast of Newfoundland, correct?
Prof. HAEDRICH: Yes, it's a very large area and we've been working, studying these fish communities here for something like 20 years.
FLATOW: And that is one of the most famous fish areas in all of the Atlantic where the North Atlantic cod used to reign supreme, but no longer.
Prof. HAEDRICH: Certainly it is. This is toilers of the sea and all that kind of thing: 500-year fishery.
FLATOW: But went out of business basically, the cod fishery.
Prof. HAEDRICH: Yes. The cod fishery did. It collapsed about--in 1992 and the fishery has been basically closed since then and what our interests have been in, particularly Jennifer's, has been to try to see what is going on in other parts of the ecosystem rather than just focusing on the commercial species itself. But we're interested in the entire system.
FLATOW: Well, Jennifer, let's talk about what you found. Your current study looked at the deep-sea fish in the northwest Atlantic. Tell us about them. Are the all commercially valuable fish? What kinds of fish? What did you find? Give us a little thumbnail.
Ms. DEVINE: Well, two of the species are--or were commercial species, the two grenadier species were taken commercially, and one still is taken as bycatch in the Greenland halibut fishery. On the other three species are mainly taken as bycatch within the other fisheries and discarded. And so what we found was we analyzed research survey data that the Canadian government collects, and we found that these five species were within a 17-year time period declining in excess of 87 percent, and that over three generations they were declining in excess of 95 percent.
FLATOW: Ninety-five percent. Which species are we talking about in both these areas?
Ms. DEVINE: All species were declining greater than 95 percent over three generations--all the five species we looked at.
FLATOW: Wow. Can you give us the names of those?
Ms. DEVINE: That's roundnose grenadier, roughhead grenadier, spinytail skate, spiny eel and blue hake.
Prof. HAEDRICH: You're not going to find these in any fish markets, I might add. They're usually just sold abroad and they're not really very desirable fish.
FLATOW: So what's the point, if I might be so pointed, of this study then? Why should we care about that?
Ms. DEVINE: Well...
Prof. HAEDRICH: Well--go ahead, Jennifer. You've got a good handle on that one.
Ms. DEVINE: Well, this study contributes to the greater base of knowledge that we're collecting on the system, and what we're showing is that within the deep sea changes are occurring and that the ecosystem is changing. And this could have a detrimental effect on everything within the ecosystem, including those species that we consider important because we eat them.
Prof. HAEDRICH: Yeah. You can think of an example, you know. We know on land if you go out and you clear-cut a forest, say, that what you end up with maybe is a grassland and it never goes back to being a productive forest area, and this is a lot of the thinking now for these deep ocean systems too, so when we see changes going on in fish wish aren't even being targeted, we get quite concerned.
FLATOW: I see. Are some of the fish that we eat--are they also deep ocean fish?
Ms. DEVINE: Greenland halibut...
Ms. DEVINE: ...is a very common deep-sea species.
Prof. HAEDRICH: And then there are things like orange roughy and Chilean sea bass, which are deep-sea long-lifed fishes too.
FLATOW: Yeah. We had Sylvia Earle on the program a few weeks ago and she was telling us about how those populations are decimated also.
Ms. DEVINE: Yeah.
Prof. HAEDRICH: Yes, they are, and like the ones that we studied, they are very long-lifed; they don't--ours are matured at an age of anywhere between 17 and 20 and orange roughy may not mature until they're about 45 years old, so that once you fish 'em down, the recovery time, if there ever is to be a recovery, is going to be very, very long.
FLATOW: So once you eat--if you eat an orange roughy for dinner, that fish on your plate could be 40 or 50 years or older?
Ms. DEVINE: That's correct.
Prof. HAEDRICH: That's right. Could be a Victorian age fish.
Ms. DEVINE: Yeah.
FLATOW: And so that it would take that many years to replace that fish.
Ms. DEVINE: That's...
Prof. HAEDRICH: That's right, and usually conservation biologists like to look five generations into the future so that, again, from our study we're not going to know even if some steps are taken right now, we won't even know if they've had any impact for another hundred years.
FLATOW: 1 (800) 989-8255 is our number. Why not, you know, set up fish farms for these deep-sea fish? Or is that possible? Or the other food fish we eat, like they do for salmon and other farming techniques.
Ms. DEVINE: Well, these are species that are living at depths greater than 400 meters. The grenadier species are very common from 6 to 800 meters and they extend even down to 1,200 meters, so it's--they're not something that lives within shallow water where we normally have our fish farms. In addition, if you tried to find these fish, you wouldn't be seeing them reaching a marketable size for a good 10, 15 years.
FLATOW: Right. It's like planting a forest.
Ms. DEVINE: Exactly.
Prof. HAEDRICH: That's right. But there's another thing about it, and that applies to fish farming generally. Fish have to be fed fish, so you've got to go and get that food for them somewhere, and those are usually taken--or almost entirely taken out of wild ecosystems, made into fish meal and even not all that fish meal goes into the fish like even fed to salmon. Some of it's fed to chickens, some of it's fed to pigs so that in the ultimate aquaculture is not something that's going to necessarily feed the hungry of the world.
FLATOW: Yeah, it's better to go right from the plant to the person instead of through the fish.
Prof. HAEDRICH: Right, from the wild--when you are eating wild fish, it's not only better for you, but it's using all these so-called ecosystem services, it's being raised for free.
Prof. HAEDRICH: You don't have to feed it.
FLATOW: Well, then how do you preserve the wild fish so that there are enough of the wild ones for us to eat?
Ms. DEVINE: Well, what we're calling for in the Nature paper, and it's just one method that we're putting forth, is the implementation of deep-sea protected areas or marine-protected areas. And this will protect, like, key habitats such as deep-water corals that these fish we assume to be associated with or life stages of these fish are associated with, and this would help lessen the fishing mortality upon these species.
FLATOW: And then you'd also protect some of those deep-water corals, 'cause don't the nets just drag everything like plow through the ocean floor?
Ms. DEVINE: Exactly.
FLATOW: Rip everything up there.
Prof. HAEDRICH: Yeah, those nets do. The nets, most people don't realize, are huge affairs. They weigh anywhere from 10 to 15 tons and you can fit a 747 inside one of 'em.
FLATOW: Wow, and it's just dragged along the bottom and catches whatever it catches.
Prof. HAEDRICH: And they're dragged along the bottom and it's like dragging a 747 across the thing, so it doesn't...
Prof. HAEDRICH: ...go lightly, tread lightly on the earth.
FLATOW: And so you have coral that could take tens of thousands of years to grow and they're wiped out in one scoop.
Ms. DEVINE: In one pass, yeah.
Prof. HAEDRICH: Exactly, and there's plenty of literature to actually document that that's going on.
FLATOW: 1 (800) 989-8255. Let's go to the phones. Let's put Mir in Savannah. Hi, Mir. How are you? Oop. Mir? Go ahead.
MIR (Caller): Yes. Yes. My question is why don't we place a moratorium on these species of fish as we have done so with the Chilean sea bass for a period of time.
Ms. DEVINE: A lot of these species are being captured in the bycatch of other fisheries, so we would have to call for a moratorium on deep sea fishing in general. Now we've seen a call for this over on the other side of the Atlantic where they've actually, as a management, have decided to reduce fishing mortality on the deep sea by 10 to 20 percent. So there is a beginning to this, but it hasn't really caught on over here yet.
MIR: OK. So if this catches on, this would preserve and lengthen the species of the fish for a longer period of time. If it takes 45 years for a certain species to grow, then we need to start considering doing that at this moment so we can have these species existing for the near future for our generation.
Ms. DEVINE: That's it exactly.
FLATOW: All right. Thanks for calling.
MIR: Thank you.
FLATOW: 1 (800) 989-8255. Do you think there is a real possibility that you can get international cooperation to allow a species of fish, whether it's the deep-sea water ones or the ones in more shallow water that, you know, are schooling, that we depend on for the old cod--things like that--to come back? Is that a workable idea?
Prof. HAEDRICH: Well, it's a difficult thing to achieve, if you want to follow what's happened in history. But there are sort of lurching attempts to sort of do the right thing. Jennifer mentioned what's going on in Europe. And then there are organizations that endorse responsible fishing and so on. I was talking to someone here in Newfoundland just earlier today who's advocating a return to a much gentler type of fishing; that's with hook and line. That's what the centuries-old fishing was done here. To do it inland and to have larger areas of the offshore protected as places for the regeneration of codfish stock.
Ms. DEVINE: We also see a call for co-management of fish stocks, like such as the straddling stocks, and what this is is getting all the countries together who are interested in fishing on those to talk about sustainable practices and getting everybody agreeing rather than having one body set the quota and divvying it up, not in those countries' best interests.
FLATOW: But people are going to want their sushi. You know what I mean? I mean...
Ms. DEVINE: Yeah.
Prof. HAEDRICH: Yes, we know that.
FLATOW: How do you make su--is there a happy medium where people can have their sushi and also not wipe out the tuna, you know?
Prof. HAEDRICH: Well, I think that the--that's why we think that these marine protected areas are the best bet. They're kind of like national parks, you see?
Prof. HAEDRICH: You set aside a large area and you leave things alone and you let nature take its course in there, and you can exploit things around the edges of it but you always have something left there that's functioning the way that it ought to and so on. We don't--we're not saying that you should bring fishing to an end. We think that that would be terrible. Fifty percent of the world's protein comes from fishing, but you've got to start being less greedy and more tuned into the pace of nature.
FLATOW: Talking about fish this hour on TALK OF THE NATION/SCIENCE FRIDAY from NPR News with my guests Richard Haedrich and Jennifer Devine. Our number: 1 (800) 989-8255.
Richard, can you describe one of these habitats that you're talking about. You say it's big. Give us a scale of how you might set one up or one that might be working now.
Prof. HAEDRICH: Well, the--they're--the most--best world example is the Great Barrier Reef, which is a whole place, you know, off of Australia, 3,000 miles long, is a marine-protected area. It has various levels of use throughout. Some places where there's--they're practically no-go areas. You're not allowed. Other places where even commercial fishing can take place. There was great opposition to this originally from fishermen, but by now, that that's put in place, and they're finding that the fishing is much improved around the--because there are--the large spawners are protected and so on.
We're talking about something in the deep sea. The deep sea corals have caught peoples' fancy, and there's some move to protect those animals, and that would be--protect the fish, too. But the size of the things that we're talking about are thousands of square miles so that this is not a lightly taken effort. There's going to have to be a lot of players brought on to believe that this will work.
FLATOW: Yeah. Jennifer, these fish that you say have been decimated by up to 95 percent, these five different kinds of fish, are they so decimated that they should be classified as endangered yet?
Ms. DEVINE: Well, using the World Conservation Union criteria, they do qual--meet that cri--they do meet that criteria. It's not up to us to say they should be considered endangered or extinct or on the verge. It's up to these organizations because they take into consideration the global range of the species and all kinds of pressures upon the species when they make their listing.
FLATOW: So you don't want to advocate that they be declared endangered?
Ms. DEVINE: Getting into the policy of it isn't really my forte. I do the science and then I...
Prof. HAEDRICH: On the other hand, it is true that there are all kinds of advantages that come from actually being listed as an endangered species.
Prof. HAEDRICH: First of all, it's just an obvious warning to be careful, but then certain--in certain places--and in--Canada is one of those--that there is this--turns particular focus on study those things. More research is done. There's funding for research and so on. And furthermore, when a species is declared endangered, then that gives countries certain powers probably--I don't know if this has ever been tested--to protect it that it wouldn't have if the species were not internationally recognized as being endangered.
FLATOW: Yeah, you could bring it up for treaties and things like that.
Prof. HAEDRICH: That's right. You can use it as a negotiating point.
FLATOW: Yeah, so it might be--how do you petition? I guess you'd have to petition then somehow for it to be endangered--to be considered endangered.
Prof. HAEDRICH: Well, there's--part of it--the way that we think is the most effective is to do what we've done is to document these--what's going on in the light of very cold, hard and often very boring science. But then it's up to various national committees, who are looking at all these things and also non-governmental organizations who are--have an interest in the deep ocean to bring these forward and ask that they be considered for listing.
FLATOW: All right, well, we wish you good luck in doing that cold, hard, boring, but necessary, science for us.
Ms. DEVINE: Thank you.
FLATOW: Thank you very much for taking the time to talk with us.
Prof. HAEDRICH: Thank you for having us.
Ms. DEVINE: Yes, thank you.
FLATOW: You're welcome. Richard Haedrich is professor emeritus of biology at Memorial University in St. John's, Newfoundland, Canada. And Jennifer Devine is a doctoral student there at Memorial University.
We're going to take a short break, come back, switch gears, go back to a little bit more good news about an actual reserve that is working and functioning in the Caribbean and how the populations have changed for the better. So stay with us. We'll be right back after this short break.
I'm Ira Flatow. This is TALK OF THE NATION/SCIENCE FRIDAY from NPR News.
FLATOW: You're listening to TALK OF THE NATION/SCIENCE FRIDAY. I'm Ira Flatow.
We've been talking about the statistics about the declining numbers of fish worldwide overstressed by overfishing. We've talked about the need for marine reserves. Well, this is--these are places where fishing is restricted and there is some interesting news in today's issue of the journal Science. My next guest and his colleagues report on a marine reserve in the Bahamas and they found that a long-standing no-fishing zone benefited not only the Nassau grouper, which is the reserve's top predator, but also the other fish species, and, ultimately, maybe even the coral reefs.
So for the rest of the hour, we're going to talk about this experiment, I guess you might call it. We'll talk about what it is and how it's working. Our number: 1 (800) 989-8255.
Dan Brumbaugh is a senior conservation scientist in the Center for Biodiversity and Conservation at the American Museum of Natural History. He's also a visiting scientist at the National Marine Protected Areas Science Institute in Santa Cruz, California. He joins us now by phone from his office there.
Welcome to the program.
Mr. DAN BRUMBAUGH (Senior Conservation Scientist): Thanks very much.
FLATOW: Tell us about this reserve, how it was set up, how it works, what's going on there.
Mr. BRUMBAUGH: Well, the reserve that was the central focus of this paper is called the Exuma Cays Land and Sea Park in the central Bahamas. It's a national park managed by the Bahamas National Trust in the Bahamas. It was set up in 1959 on the basis of a--some initial surveys of wildlife in the area. But it only became a marine reserve--that is a no-take area--in 1986. So much of the ecosystem patterns and processes that we're interested in presumably have only been taking place since that moment 20 years ago.
FLATOW: So this is a total fishing ban, not a controlled take, but all fishing stopped?
Mr. BRUMBAUGH: Yeah, for the most part. It's a complete no-take reserve. People say there's probably poaching around the edges but in the middle of the park it's pretty well-enforced and a good place to be looking at these comparisons between fished and no-fished areas.
FLATOW: All right, so tell us about what you observed over the years and what is happening there.
Mr. BRUMBAUGH: Well, we--I should say at the front, that we haven't done a long-term study. This is really a snapshot of...
Mr. BRUMBAUGH: ...how things look there. But we did look at the park in the context of studies of natural systems throughout the Bahamian archipelago. So there's a--we've looked at the spatial variation, the natural variation in fish communities and in bottom communities throughout this area in order to be able to say that the things that we see in the park that are different are truly due to the reserve status and not just this natural variability.
So the first thing we observed then was that there's a--as expected, there's a large number of Nassau groupers in the park relative to the surrounding areas.
FLATOW: Is that like the big fish on the block?
Mr. BRUMBAUGH: Yeah. They're a really striking and charismatic fish. Lots of people like to eat them so they're fished heavily outside the park. And they're--for divers they're great because they don't move around much. They sort of hunker down underneath ledges and things and you can sort of get kind of close to them and look at them.
Mr. BRUMBAUGH: And--but they are a big predator. They can get very big and they eat smaller fishes and other things when they have the chance.
FLATOW: And so when the park--when they're left alone to be unfished in the park, what happens to them? Do their populations grow? Do they take over the park?
Mr. BRUMBAUGH: Well, yeah. So there's about three times as many Nassau groupers inside the park as immediately outside and about seven times as many in the park as in sort of the average of the overall Bahamas. So there's quite an accumulation of predators there. And that--we wondered what impact that would have on the rest of the community and some of the ecosystem processes. And part of our question about that was because some people have suggested that you might get some unintended consequences from marine reserves, and that's if you protect a lot of predators, those predators can maybe dampen some of the other levels of the food chain or food web such as the herbivores, the things that eat plants. And if you reduce the plant eaters, then you might have a bloom of plants or algae, which could have a negative impact on the corals that those algae compete with.
FLATOW: Right. Right.
Mr. BRUMBAUGH: So that was a hypothesis, I guess, that we had going into this research. But as it turned out, we didn't see that. There wasn't that sort of strong trophic cascade. That's what that sort of top-down effect is called, is a trophic cascade. We didn't see that and that's because nature is actually a little bit more complex often than we hypothesize it to be and that the herbivores that we were studying, parrot fishes, are diverse themselves. So there's some species which appear to be vulnerable to the groupers but there are other species that attain a size that makes them essentially immune from grouper predation.
FLATOW: So you get a parrot fish that develops, that naturally selects out, that's too big for the groupers to eat?
Mr. BRUMBAUGH: Yeah, they just att--basically they just attain a size that groupers can't swallow. It's too big for the groupers' mouth. So those essentially get a free pass from predation within the reserve, but then they still benefit from being protected from incidental catch in fish traps outside the reserve.
Mr. BRUMBAUGH: But those big parrot fishes basically become much more abundant in the reserve than outside. They're the same size inside as outside, but they're more abundant and so they have a much more intense effect on the algae growing on the reef.
FLATOW: Well, does that mean the coral are healthier or do the parrot fish chew on the coral?
Mr. BRUMBAUGH: That's an excellent question, actually.
FLATOW: Because I've been scuba diving many times and I've watched parrot fish chewing on coral. You know, I was wondering maybe if you have more that's destroying the coral.
Mr. BRUMBAUGH: Yeah, well, as I said, that's an excellent question. What parrot fish do is they basically scrape the surface of the reef. And sometimes they chew on coral, as you say, but usually they're chewing on algal turfs, and by chewing on the algal turfs they're basically clearing off space that allows other corals to settle and grow on this freed-up space.
Mr. BRUMBAUGH: So, I mean, I can imagine if you had way too many parrot fishes that you could have--and you had a lot of coral already, you would be having a negative impact from those parrot fishes on corals. But when you don't have that much coral and there's a lot of algae, the parrot fishes are essentially helping the corals.
FLATOW: So things do stay in balance. They don't go out of control like you hypothesized might happen?
Mr. BRUMBAUGH: Right. In this case, there's no strong trophic cascade and that's...
Mr. BRUMBAUGH: ...that was a little bit of a surprise to us. You know, there's other systems that people have studied, such as kelp forests in California, where you do see this really strong trophic cascade. If you have sea otters present, they consume all the sea urchins, or many of the sea urchins, and that allows the kelp to thrive. So you get kelp forests in those patches where there's sea otters. And where you don't have sea otters, the sea urchins come out of hiding. They proliferate, they aggregate and they, basically, mow down all the kelp, creating what are called sea urchin barrens.
FLATOW: Right. Could you ever get to the point at the reef where there are enough grouper that you might open it to limited fishing at all? Or is this just purely an experiment that you're watching happening?
Mr. BRUMBAUGH: Well, I mean, grouper are fished in other places throughout the Bahamas.
Mr. BRUMBAUGH: I mean, there's not--this is the biggest marine reserve that exists there and grouper are fished, you know, either lightly or heavily depending on where you are. So nobody's talking about closing off everywhere to fishing. This is a national park, too, so that...
FLATOW: Yeah, yeah. You're not going to...
Mr. BRUMBAUGH: ...was the motivation for why they banned fishing in the first place.
FLATOW: Right. Yeah, you're not going to be fishing in the national parks. In the segment prior to this one we were talking about the challenges of setting up a marine reserve in the deep sea of the northwest Atlantic because it would require the cooperation of many fishing nations. So there would be that kind of coordination problem. Was that a simpler process here because the Bahamian government controlled these waters?
Mr. BRUMBAUGH: Yeah, it was--it is a simpler problem than an international one, but I think in the day and age that this protected area was set up, it was even simpler because it was a very top-down governmental decision to, you know, designate this area. There's new protected areas being considered in the Bahamas and those are going through a much more arduous, time-consuming but collaborative process where they're consulting with local communities to get local reactions and input into where the best places to put new reserves could be.
FLATOW: So they're working more with the local communities...
Mr. BRUMBAUGH: Yeah.
FLATOW: ...than steamrolling them what they want done.
Mr. BRUMBAUGH: Right, and that's something that we're interested in as well. This work that's featured in the Science article is just part of a much larger study involving a lot of other collaborators at eight different institutions. And we call it the Bahamas Biocomplexity Project because our major source of funding is from the NSF Biocomplexity in the Environment program. And we're trying to look at not just how a single reserve works, but how a whole system of marine-protected areas across the whole archipelago could work.
Mr. BRUMBAUGH: And to do that, in addition to these ecological interactions that we're talking about in the science paper, we also have to talk about how water moves across the archipelago or through the archipelago and how that moves organisms from place to place. And also what the social fabric is across the whole archipelago; that is...
Mr. BRUMBAUGH: ...how do cultures and economies vary from place to place and how to integrate that social complexity with that ecological and oceanographic complexity.
FLATOW: Mm-hmm. You've been studying--you've been monitoring this, did you say, since the '60s, this area?
Mr. BRUMBAUGH: No...
FLATOW: When was it?
Mr. BRUMBAUGH: ...we've--other people have been working in the park and in the surrounding areas...
Mr. BRUMBAUGH: ...for a while.
FLATOW: Yeah. Now my question--I was trying to lead to a question that may be irrelevant, but I'll ask it. I always ask irrelevant ones anyhow. Have you noticed any influence of warming of the water possibly from global warming on these reefs and these park areas?
Mr. BRUMBAUGH: Yeah. I wouldn't say our research has done that, but certainly other people's research has...
Mr. BRUMBAUGH: ...noted an increased frequency of coral bleaching and also coral diseases throughout the area.
Mr. BRUMBAUGH: And that's one of the--you know, that's one of the fundamental challenges that are facing corals. And, in a way, that's why the results from our research are hopeful in that you can--I mean, corals are facing a lot of obstacles and threats to them, but our research shows that if you set up a marine reserve, which has its primary impacts on fish populations, you're still also helping the corals in their likely ability--in their possible ability to recover to their former status--their former glory in the Caribbean.
FLATOW: Yeah. 1 (800) 989-8255. We're talking about fish preserves on TALK OF THE NATION/SCIENCE FRIDAY from NPR News, talking with Dan Brumbaugh.
And you mentioned that the--Sylvia Earle was talking about--I think she was talking about the staghorn corals off--in Florida that are just about gone. I mean, I could hardly believe what--you know, what I heard about that.
Mr. BRUMBAUGH: Yeah.
FLATOW: Is that true in your neighborhood, too, or can you actually see something like that maybe rebound?
Mr. BRUMBAUGH: Well, there are signs of rebound but Sylvia is right that the coral reef communities have changed dramatically, you know, over the last 20 years and even over a much longer period of hundreds of years. People have looked at sort of the long-term changes of--human-caused changes in the Caribbean. But over the last 20 years the staghorn and the elkhorn corals, which used to form major zones...
Mr. BRUMBAUGH: ...along reefs have largely disappeared. And so you really just see remnants here and there of those two corals.
FLATOW: Yeah, ...(unintelligible).
Mr. BRUMBAUGH: In fact, those two corals are being considered for listing under the Endangered Species Act by the federal government right now.
FLATOW: It's hard to believe. I remember there's so many forests of them, so to speak, that I used to get tangled up scuba diving and snorkeling in them, you know...
Mr. BRUMBAUGH: Yeah.
FLATOW: ...in the real shallow water. It's hard to believe they're gone.
Mr. BRUMBAUGH: Yeah, it is. For people who have that long-term perspective, it's a very different place. And, you know, those long-term perspectives are really good, and most people don't have them. And that's why when newcomers to snorkeling or scuba dive see the reefs, they think they're beautiful but they don't really know what they're missing, what used to be there.
Mr. BRUMBAUGH: And there's a name for that sort of phenomenon, and it's the shifting baseline syndrome, and it's nice to have those long-term perspectives, basically, how things used to be.
FLATOW: Yeah. Let me see if I can get one more point. We've also heard that the sharks have been overfished and are being killed at enormous rates. Do you notice sharks at the reefs here finding new homes where they might not have?
Mr. BRUMBAUGH: Well, we did actually. It wasn't--we didn't really see enough sharks to make it a major part of our statistical analysis but just--we definitely saw more sharks in Exuma Cays Land and Sea Park than we saw outside it in other areas of the Bahamas. And it was sometimes quite funny actually. We'd have some of our researchers swimming along on their fish transects looking--counting all the little things swimming above or growing over the reef and a shark would cruise by totally unbeknownst to the researchers.
FLATOW: That was a shock for the shark, too, maybe.
Mr. BRUMBAUGH: It may be. You know, it's humorous to everybody else, you know, watching these sharks...
Mr. BRUMBAUGH: ...you know, these very benign sharks, you know, cruising by. But just humorous to watch, you know, the--our research divers with their heads looking down totally unaware of these big things swimming around.
FLATOW: But they--so they're also seeking possible refuge there, too. But you're saying you see a few more than you might expect?
Mr. BRUMBAUGH: Well, yeah. I mean, I'm going out on a limb here, but, you know, I suspect that just the fact that this area is protected and other fish--you know, fish populations like Nassau groupers and the parrot fishes that we discussed...
Mr. BRUMBAUGH: ...and anything else that gets caught in traps or are somehow impacted by fishing or other human activities elsewhere are doing well in the park. And that's going to attract these bigger predators like sharks.
Mr. BRUMBAUGH: You know, it's also possible that certain tourist operations, which sometimes feed sharks are contributing to the sharks coming into these areas more heavily. And there's certainly a lot of tourism activity that operates around the Exuma Cays Land and Sea Park and is dependent upon the health of that ecosystem.
FLATOW: Well, we know how tourists like to feed the animals--the wild animals in the parks, whether it's underwater or in Yosemite or wherever it is.
Mr. BRUMBAUGH: Yeah, that's true.
FLATOW: Yeah. Thank you for taking time to talk with us and good luck to you.
Mr. BRUMBAUGH: Thank you very much.
FLATOW: You're welcome. Dan Brumbaugh is a senior conservation scientist in the Center for Biodiversity and Conservation at the American Museum of Natural History and he's a visiting scientist at the National Marine Protected Area Science Institute in Santa Cruz, California.
FLATOW: If you'd like to write us, surf over to our Web site at ScienceFriday.com. You can leave e-mail for us there. Also SCIENCE FRIDAY's Kids Connection is there, free teaching curriculum that we make out of SCIENCE FRIDAY. Just click on the `teachers' button on the left side of the page and take it to school with you.
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