Snorkeling with Some Wild Dolphin Friends – or Another Day in the Office for Denise Herzing | Miles O'Brien Productions

Snorkeling with Some Wild Dolphin Friends – or Another Day in the Office for Denise Herzing


For more than three decades, behavioral biologist Denise Herzing has tracked and observed a pod of wild spotted dolphins that live in the warm clear waters of the Bahamas. She’s learned an awful lot about their behaviors and their communication–or is it a language? Denise has as good a chance as anyone to find out what the dolphins might be saying to each other. But the question is: if we could communicate with them, what would we say? Maybe we should start with an apology.

[maxbutton id=”5″ ] [maxbutton id=”8″ ]

Help us improve this podcast: take our short survey


Miles O’Brien: Hello I’m Miles O’Brien. Welcome to another edition of Miles To Go.

When I was young, one of my favorite must-see TV shows was Flipper, the story of the Atlantic bottlenose dolphin who always seemed to save the day in the nick of time. Now that I know more about dolphin intelligence and social structure, as I look back at that show I realize how cruel it really was to force the dolphins that played Flipper–and there were more than one, mostly female–it was cruel to make them work so hard for their food.

But be that as it may, I always wished that I could one day swim with dolphins–not captive dolphins, that too in my view is cruel.

When Denise Herzing was growing up in Minnesota about the same time, she thought the same thing. But instead of discarding the thought in favor of other pursuits–in my case, it turned out to be journalism–Denise remain focused like a laser beam on understanding dolphins. And she has committed her career to doing just that.

It eventually led her to Florida and the establishment of the Wild Dolphin Project. Thirty four years later, she has achieved great insight into the previously secret lives of spotted dolphins… And she’s working on ways to understand them literally. What do the clicks and whistles and all those noises really mean?

My cousin is a famous underwater photographer, Ruth Petzold, and she’s an old friend of Denise’s. She serves on the board of Denise’s foundation. Last month, Ruthie booked some space on Denise’s research vessel, the Stenella, and invited me to tag along. It was a life-changing experience.

I sat down for a chat with Denise after our amazing nine-day voyage.

Miles O’Brien: This was field season 34, trip number three or four? What was it?

Dr. Denise Herzing: Three.

Miles O’Brien: So 34.3. How was that typical, unusual? Put this in the broader context, what we did.

Dr. Denise Herzing: Sure. So you were out on the third trip of our 34th field season. I would say it’s a pretty typical trip. Weather was decent but a little tropical stormy. We had some days without dolphin’s completely but then we had great dolphins some of the other days.

We saw some terrific behavior actually. Some sound behavior, courtship behavior, mating behavior and repeat animals, so I’m sure you recognized few in the water by the end of the week.

Miles O’Brien: It’s kind of amazing to me that you just happen upon the same group. They find you, you find them whatever. You’ve figured out how to connect, haven’t you, over the years?

Dr. Denise Herzing: Well, the dolphins are resident in that area. And in any given 10-day period for example, they’re probably feeding in the same area or interacting in the same area. That can shift but we’re lucky that we get repetitive sightings.

Miles O’Brien: Just give us a few words, cause we began on the EARs missions. Tell us about the EARS and what they’re all about and what kind of data you hope to gather off of those?

Dr. Denise Herzing: So this year, we did something new. We deployed some passive acoustic listening devices called, “EARS,” Ecological Acoustic Recorders.

And basically, they sit on the bottom. They record, in our case, 30 seconds every five minutes for a month and then we pick them up. We download the data. We put them back. And the idea is that they’re listening why we are there. So we can go through data and see what sounds are there, figure out what species went by. And it gives us a way to find animals that aren’t easily findable anymore in certain areas, and we can go back and maybe try to find them.

Miles O’Brien: Find an individual animal, a type of animal? I mean, would you able to identify by a whistle for example, that kind of thing? How do you know which you’re hearing?

Dr. Denise Herzing: Well first and foremost, the EARS are used to just show the presence of dolphins, so echolocation clicks, whistles. So the data will show us there were whistles and clicks recorded on June 1st at two o’clock in the afternoon. So we know some dolphins were there. Then we can go through the data and maybe pull out the species. And if we’re lucky, we could match signature whistles if we have them on file.

But the idea is that, we want to know when they’re there when we aren’t there, so we can find them more readily in the future.

Miles O’Brien: Is this the first time you’ve been able to sort of put a security camera, if you will, on the dolphins and monitor them when you’re not present?

Dr. Denise Herzing: This technology is not something we’ve used because our focus is to find them in the water, get underwater footage, correlate sound and behavior and try to figure out their lives. These devices are used more in murky water environments. Places that it’s difficult for researchers to get, so they leave recording devices. It’s just new for us because the animals have changed their locations and so just want to get a handle on where they are when we’re out there.

Miles O’Brien: Deciding where to put these devices is obviously a big part of the art and science of this. Are there dolphin corridors or dolphin interstates and is this where you intended to put these?

Dr. Denise Herzing: We put the devices where we had regularly interacted with dolphins in the past but we weren’t seeing them in the last few years, so that’s the idea. In fact, the first time we deployed the first EAR, the dolphins showed up, so I guess it’s a good place but that was pretty funny.

Miles O’Brien: They like checking out your work.

Dr. Denise Herzing: “Hey, we’re here. Sure.”

Miles O’Brien: This was in the area where you spend a lot of time seeing a lot of the individuals we ended up seeing further south in Bimini. This was their home for a long time, right? Do we know a little bit about why they moved and is that part of what this is — is that one of the questions you’re hoping to answer?

Dr. Denise Herzing: The dolphins had been basically resident for 28 years. We could go out…and there are sandbanks in the Bahamas. And so, they have access to all these food on the deep water edge, so it appeared that they made their home on that little Bahama bank in this case.

In 2013, we went out there and we were missing half of our dolphins, which is a little disconcerting. You don’t know if orcas have come through or if there’s Navy sonar involved, whatever. So we did find them a hundred miles away but we were wondering…why would you leave your home after 28 years of a stable place?

So we started looking at oceanographic data and we had kind of noticed that the fish had kind of disappeared and we thought maybe there was something going on with the environment or climate change. So after looking at a NOAA database that records a lot of different things, one of them was surface chlorophyll which is a proxy for plankton, we saw clearly there was a significant drop over the years which probably relates to the fish crash. So our best guess right now is that the fish and squid just disappeared and they had to go somewhere else to feed.

Miles O’Brien: Interesting. But you really had to do quite a bit of sleuthing to figure that out didn’t you?

Dr. Denise Herzing: Yeah. But we compared different areas. Other areas did not have this chlorophyll reduction. It was just the area where the dolphins fished in this certain way. It was pretty clear something happened there. Now, it will also be interesting to see if it comes back and if we can predict it with the data from NOAA.

Miles O’Brien: As best you tell, would this be natural cycle or do we know if there’s some other cause?

Dr. Denise Herzing: We really don’t know what causes chlorophyll drops in our case. The science tells us that it would be lack of sunlight. Which is hard to believe in the Bahamas, right? The other is nutrient cycles. Nutrient cycles can be driven by upwelling, different winds blowing nutrients on and off the sandbank. And the other thing that has actually shifted out there is the wind direction, probably because of climate change and changing jet streams and fronts coming in and out. And so, winds that are normally southeast in the summer were coming from the west, eastern or southwest, which really changes the tidal flow on and off the sandbank. So we suspect it was probably the nutrient circulation that just got disturbed for probably climatic changes.

Miles O’Brien: I keep stumbling in on, in just about every story I run into, these kind of unintended, unforeseen consequences of climate change that you really wouldn’t think about. Talk about the knee bone connected to the thigh bone stuff. It’s amazing how everything is related, right?

Dr. Denise Herzing: Yeah. And they can be subtle changes and very localized changes. But now, it’s impacted the lives of, in this case, 50 dolphins that left and now those dolphins are trying to integrate with the local pod in this new area. So now, you’ve got all these behavioral things going on and now you’ve got added pressure on this other dolphin group. So it gets really complicated for the animals.

Miles O’Brien: It’s kind of a micro-version of the macro scene for the planet. If you start extrapolating that out you realize this is why climate change is so potentially cataclysmic when you have all these things happening.

Dr. Denise Herzing: Yeah, it is cataclysmic and unless you have a long-term project where you know the baseline and you can see the change, a lot of these changes will actually go undetected.

Miles O’Brien: Just a couple of more things on the EAR. What are the big questions you hope to answer with the EAR? What’s on your mind and what do you hope to garner from it? Or are you just fishing for data and seeing what happens and trying to mesh that with your other data?

Dr. Denise Herzing: Yeah. The big questions with the EARS are really, when do the dolphins come by these locations? It doesn’t give you a long stream of audio and it’s certainly is not giving us video. It’s really about when they show up in these locations so we can find them.

Miles O’Brien: Okay. So, just another little piece of the puzzle, probably a small piece of data.

Dr. Denise Herzing: It’s another little piece of data just from some new technology that we hope will add to our abilities to find the dolphins.

Miles O’Brien: Okay. So, a viewer at home is going, “Why don’t you put a tracking device on these dolphins, Denise? What’s the matter with you?” I’m sure you’ve considered a lot of, and I know of some researchers do this. Either tracking devices, cameras, et cetera. What’s your philosophy on doing that kind of thing?

Dr. Denise Herzing: So the Bahamas is one of the few places in the world where you can observe animals underwater. That’s why I chose the location and that’s how we’ve worked. And one of the basic principles we work with is behaving ourselves in the water with the dolphins and our motto is, “In their world, on their terms”.

If we started grabbing them, putting them on our boat, drilling a hole through their dorsal fin with a satellite tracker, I’m pretty sure they would not come around the boat and let us watch their behavior. So, it could give us really interesting information and of course many researchers use it in cases where they want to analyze habitat, distribution where the animals go. In our case because they’re resident and we are shooting for underwater behavior and sound we just don’t do it.

Miles O’Brien: Okay. But it’s like a trade off right? I mean I’m sure if you could figure out a way to do it you’d love to have that kind of data right?

Dr. Denise Herzing: Science is always a tradeoff. If in the future, like technology goes, there will probably be some development. I mean there are already suction tags you could put on animals that would just annoy them but it probably wouldn’t hurt them but they only stay on them for a day or two. Does that give you enough information? I don’t know. Then how many do you tag, right? Do you tag two juveniles or do you tag a bunch of adults and juveniles and get the whole picture? So it becomes a question of what data are you trying to get. So we just feel like it’s more valuable to be non-invasive, have the animals trust and let them show us their society underwater.

Miles O’Brien: You did mention the key point which I think we need to get across here. That how special this particular part of the whole is to do what you do. You’ve got clear water, shallow depths, et cetera. Just walk us through why this is the ideal kind of natural laboratory.

Dr. Denise Herzing: So most places in the world, researchers work from the surface because, number one, the water is murky, sometimes it’s just simply dangerous whether it’s wave action, sharks, who knows. But you can’t see underwater most places in the world. You’re pretty limited to the tropics. The species we work with is also fairly gregarious. They seem to have – I wouldn’t say an easy life but they have pretty good access to resources historically so it probably gives them more playtime. And we’ve habituated them over the years for our presence in the water and try to behave ourselves so that they show us their natural behavior whether its foraging, fighting, mating all those things.

Miles O’Brien: So you’ve had a long time interest in the natural world and in particular the sea world.

So when did it become evident to you this was the place?

Dr. Denise Herzing: Well, I had actually done my graduate work in captivity. I worked in the San Francisco area at a facility trying to correlate sound and behavior. And you get a certain amount from captivity, but I didn’t like the environment for the animals. It’s quite unnatural to artifact. Their social structures in artifact. And I just set my sites on finding a place in the wild where I could observe their society and tell the story of wild dolphins.

I also had the luxury of…I saw the primate researchers like Jane Goodall, Dian Fossey and even Cynthia Moss with the elephants, plant themselves in a non-human animal society and let the animals show them their world. This involved tracking individuals, taking notes and taking data but eventually a picture emerged that you could get no other way.

So I thought, “Why hasn’t anybody done that with dolphins?” And I luckily ran into a place that had already been discovered by treasure divers where there are friendly dolphins and I went out there just to see if it would be a good research site and figured I’d invest 20 years and try to get through a few generations of dolphins and tell the story and here we are 34 years later.

Miles O’Brien: So you just show up and say, “Yeah, I’ll give 20.”

Dr. Denise Herzing: That’s what I wanted to do.

Miles O’Brien: You a big better at the casinos?

Miles O’Brien: The captivity versus wild component. You’ve had the opportunity to study dolphins in both environments. Is it like night and day? Is it different data? Are the dolphins behaving completely differently or is it just subtle?

Dr. Denise Herzing: I think most scientists would agree that there are things you can do in the wild you can’t do in captivity and vice versa. In captivity, you have experimental control, you can ask certain questions. But if you’re looking for natural behavior or societal relationships, you’re only going to find it in the wild. I think that’s really the restrictive point and remembering that we have to think about what’s good for the animals too.

Miles O’Brien: It’s interesting to me when you make the commitment to study an animal in the wild, it’s like in each case that you mentioned of your templates it’s a long run. It’s not just going to happen on your terms, it’s their terms like you say, right?

So it really enforces you to approach the science. You have to be a long run scientist, right?

Dr. Denise Herzing: Right. There’s such value in long term research whether it’s a baseline to note changes or it’s just going through a generation. For example, when I first got out there, it was all new to me. I mean I knew something about dolphin behavior but seeing it in the wild and seeing how mothers and calves act with their…how courtship goes, you get a glimpse but then it’s like a generation later you go, “Oh, they kind of do the same things but there’s some subtle differences because they’re individuals”. So a mother might have a different mothering style or she might – one mother might discipline a calves by holding them down on the bottom the other might flip up on the surface and hold the calves out of the air. So same goal just different ways of doing things.

Miles O’Brien: This kind of work doesn’t lend itself well to the academic structure of research that we have created where you have to crank out papers, do proposals and have results quickly to get the next pot of money. Is it difficult to get funding to do this kind of research?

Dr. Denise Herzing: We put out papers as soon as we have enough data but yeah, you need enough data. But remembering that the quality of the paper also matters. So some papers end up being really seminal studies because they’re ten years of data or 20 years of data and they stand the test of time for baseline information. Funding is always hard to get whether you’re working in the academic scenario or going elsewhere for your money. It’s pretty critical, of course, to be able to stay out there and do the work but it’s always difficult.

Miles O’Brien: You know, scientists are always out and about. Is it hard to keep this thing going?

Dr. Denise Herzing: Yeah, it’s very hard to keep the project going.

I mean funding number one is always the dance. You want stability. I used to joke with my Board of Directors…“You know, if we don’t have enough money, we should be out there in a row boat, at least getting photo ID.” Because if you lose track of the individual in one season, you stand to potentially lose them in your catalogue and it’s all about the individual and tracking them.

Miles O’Brien: So you sort of created this thing where you just gotta keep going. You can’t stop.

Dr. Denise Herzing: Jane Goodall didn’t even see what the fighting and the warlike stuff until 40 years. I mean it takes a while for things to emerge. And so the investment, it’s worthwhile to keep going.
Miles O’Brien: Jane Goodall, Dian Fossey…Don’t take this the wrong way but relative to you, they had it easy, right? I mean at least they could be breathing air all day, right? Explain the differences of what it’s like to go after…to take that approach for something that lives underwater.

Dr. Denise Herzing: Right. Well, I guess when you’re studying mammals terrestrially, yeah, you’re more on your own habitat, number one. You still have to trek through jungles and mud and stop to collect data in different situations and you have dangerous things. So we all kind of do the same thing.

The difference probably in our work is we have to go out and float on a boat and then we have to find the dolphins which, again, is typical. We have to be in the water. Collecting data is different because you can’t just ride on an underwater pad, at least with dolphins, they’re so quick. You have to use media like video cameras, hydrophones. And then, if you come to come out of the water and then take your data, list what you saw, and then transfer it. So I mean it’s different in some ways. I don’t know that it’s honestly that different, it’s just that it’s in the water, so you’re restricted to human challenges.

Miles O’Brien: There is a little higher bar to get over to get the data you need I think. That’s objectively true probably.

Dr. Denise Herzing: it’s definitely not easy but it is what it is. So to get that data that’s what you do. You go out, spend a lot of time waiting and looking and then when the opportunities is there, you go for it. Like in our field seasons, sometimes, we might get record of our data within two trips and the rest is kind of dribbles of catch up things. So it really depends on the weather but again, field work everywhere is kind of like that.

You could go sit on the arctic ice and wait for three months for a bowhead whale to go by and they might not ever go by. You’re not in the water in that case but, yeah.

Miles O’Brien: Would you describe it as hard work or is this a fun adventure or both?

Dr. Denise Herzing: It’s totally hard work. It’s about 95% hard work.

I mean, we just don’t run out there in the summer and do the work. We prep all year. We have to get equipment together, we have to make sure the boat is working and ready. We’re doing data analysis all winter, detective work to verify our data or check on things. We have to write grants for funding and you go out there and yeah, when we’re on the water, it’s hard work because you’re not just pointing a video camera, you’re watching who to track and follow and who’s fecal material do we need because we don’t have that so we can determine paternity. Your mind is rolling a lot in the water and then you come out and you log the data and then at nine o’clock at night, you turn on the video and you log that at night.

So yeah, of course it’s hard work. It’s a beautiful place to work, and of course, you see really cool things. But it’s hot, you get sunburnt. You’re salty all the time. But again, that is field work whether it’s in ice or in heat. It’s dealing with elements.

Miles O’Brien: You’ve devoted your career — really, your life to this. Have you ever had regrets about it?

Dr. Denise Herzing: No, I have no regrets. I want to keep going at this. The body changes but we’ve got the young ones there like they’re up to par. I trust they can get the data when I’m not out there. It’s all about trying to keep it going.

Miles O’Brien: I watched you interact with both Casey and Lia and you’re a good mentor and a good teacher. How important is that to you to kind of pass along this passion and this interest to a new generation?

Dr. Denise Herzing: I’m not sure you can pass along passion. You can identify it perhaps. You can certainly try to encourage it but I think passion is with the individual. But certainly, well they’re trained. They’re graduate students usually that are out there with me. They’re trained in the technique. They know what works and hopefully they’re open to bringing new things to the field and putting their own flavor on it. And of course, it’s important. And again, they are in a generation where there is emerging technology, emerging methods, so that’s their future, and hopefully the dolphins will stick around.

Miles O’Brien: When last we left our dolphins, they were leaving the Little Bahama Bank headed to the Grand Bahama Bank.

And this is somebody else’s turf. What has transpired as that move has occurred and what have you been able to observe as they moved into an area where a lot of bottle nosed dolphins are, et cetera, et cetera. What’s going on?

Dr. Denise Herzing: The first year, we found our resident dolphins in this new area with other currently resident dolphins. Again, we’re observing and tracking how they integrate or don’t integrate. So after about a three-year period, we did an analysis of the data and at first it looked like they were integrating but then not so much.

Now, what’s emerged now, it’s been what, five years, it looks like some of it have joined forces. For example, some of our males from the north are now hanging out with the males in this existing group, so they formed other alliances which is pretty interesting. Mothers and calves still seem to stay separate but they’re still in their kind of clusters.

So they maintain their relationships for the most part. But you’ve always got outliers and different things and maybe this is how their genetics gets mixed up and diversified.

Miles O’Brien: This is coalitions of both bottlenose and spotted males will come together. Or are we talking all spotted here?

Dr. Denise Herzing: We’re talking all spotted. Male spotted dolphins typically hang out in coalitions or alliances of three to four dolphins, and it’s usually a lifelong friendship. But what happened during this move…some of the northern males, for some reason, have integrated with some of the new male dolphins there and they seem to be hanging out together. So that’s kind of the first time we have seen that. Although we haven’t had the opportunity to see it because they were always in their home turf.

Miles O’Brien: Just a couple of words on the bottlenose versus spotted. Most people think of dolphin whether it’s SeaWorld or the Aquarium or Flipper it’s a bottlenose dolphin. These are spotted dolphins, tell us the difference.

Dr. Denise Herzing: So bottlenose dolphins are the dolphins most of us are exposed to. Partly because they’re in marine parks but they’re also coastal animals that’s probably why they ended up in marine parks. Atlantic spotted dolphins, the ones we work with, really are unstudied. We really knew nothing about that species, so we’ve been able to contribute to that.

Now, a dolphin is not a dolphin, is not a dolphin. So, things we know about bottlenose dolphins may or may not be true with other species and there’s about 30 other species. So, we have to be careful when we analyze our data to not assume that every dolphin is going to be like a bottlenose dolphin.

Miles O’Brien: They are a little smaller and they are a little more approachable and…

Dr. Denise Herzing: So, in the world, there are few places where they are sociable dolphins and they’re usually bottlenose dolphins but they are usually individuals. Out in the Bahamas, it’s kind of the opposite. The spotted dolphins seem to be the more tolerant, friendly, curious dolphins and the bottlenose are a little less tolerant and stand-offish. We’re not sure why. It could be their social structure. I suspect it’s also because they were captured many decades ago quite heavily in the area we work and they may just have a bad memory of boats or humans, that sort of thing. But their species temperament is quite different.

Miles O’Brien: are they more aggressive or — what is it?

Dr. Denise Herzing: So, bottlenose are about three feet larger than the spotteds.

And it has been our observations that they’re either travelling or eating. So, they’ve probably have to spend a lot more time hunting and digging for food than the spotted dolphins.

Their social structure is also a bit different than the spotteds. It’s still basic they still have mother-calf relationships but they tend to be a little more aggressive within their own society and that flows over when they’re interacting with spotted dolphins. They tend to bully and harass and beat up the spotted sometimes, honestly.

Miles O’Brien: The spotteds tend to stay away from bottlenose?

Dr. Denise Herzing: The spotteds reaction to dealing with the bottlenose in those kinds of aggressive situations is they form larger collisions. So, you have — we joke about the ratio. It takes about six spotteds to fend off a bottlenose.

So, they have a coordinated strategy. They form one large organism by joining forces and then they’ll be able to chase a bottlenose away usually. But they share territory. They live in the same environment. They don’t compete for food. We think they’re actually competing for females, it turns out, because there is interspecies mating — that is a whole interesting question for communication too, right?

So, we have the behavior and sounds of spotted dolphins and then we have bottlenose dolphins interacting with the spotted. So, how much do they share, sounds, behavior? I mean, they are kind of dolphins so they have the same body shape and the same anatomy but do they understand each other? Do they learn each other’s signals to interact? These are the big questions that we don’t know.

Miles O’Brien: I want to talk about languages in a sec, but one more on bottlenose. Would you make the argument that because they have to do more hunting that’s why they’re less available for you to interact with? Is that part of it, you think?

Dr. Denise Herzing: Yes, bottlenose, they spent other times surviving I think basically. It’s not unlike a human culture. If you have a lot of resources, you develop art and have more social time. If you’re always hunting and gathering that’s what you do.

Miles O’Brien: And in the case of spotted, they can play with a scarf or seaweed or whatever. And they can indulge themselves in that.

Dr. Denise Herzing: Yes, spotteds have more free time. They are able to feed themselves quicker. Their social structure is similar in the sense that they still have like 4 to 5 years as teenagers and kids so they learn the social rules but it’s a little easier I think because they are pretty well-fed.

Miles O’Brien: Watching them on the bow the stinela, you get the sense that they’re just doing it for the pure joy of it.

Dr. Denise Herzing: Sure, the ocean is a fun place. They are the original surfers. They surf on large whales. The large whales push a bow wave ahead and they get a ride sometimes. So, it’s a fun way to develop your bonds, right?

Miles O’Brien: How many animals outside of humans have the luxury of playing around, goofing around?

Dr. Denise Herzing: A lot of mammals play. And again if you look at it functionally, it’s a way to learn the rules without being in danger, right? So, you’re in the play mode so you can bully and tussle with each other but you haven’t learned the lines yet but it’s not a harmful situation because it’s play. Same with dogs. Same with cats. You know, I think a lot of mammals use that to develop their adult skills.

Miles O’Brien: People have been studying dolphin communication for quite some time. Most of it has been oddly, as humans would be, trying to teach dolphins to speak English or whatever, right? Our human language. That’s right. But there is obviously something going on there. Is it communication, is it echolocation, or is it potentially a language? What’s the correct term?

Dr. Denise Herzing: So, we don’t usually use language when we describe dolphin communication because language has really specific things that we include and we haven’t proven that dolphins or any other species really has those things like structure to their sounds or whatever their communication signals are…order, a symbolic reference. We don’t know if they can talk out of time, displacement about the yesterday or the future.

Now, some experiments have been done in captivity with dolphins and dolphin communication to suggest that they have the ability to understand human created artificial languages. So, if you teach a dolphin something like visual sign language or an acoustic language, they seem to be able to comprehend it. So, they have the flexibility. We just don’t know if they have it in their own communication system.

Miles O’Brien: And this is obviously on your list. Pretty high on your list at the moment, right? Trying to figure this out.

Dr. Denise Herzing: Some people would say, “Oh, it’s been looked at and it’s been done.” And no one’s found anything. My view on it is number one we haven’t really correlated sound with other behavior like I’m speaking right now but I put my hands into motion and then my voice gets intense and there’s all these other signals that give you the complexity of interpreting of what I’m saying and then I’m going to interact with someone and now you see a dynamic.

So, we haven’t had that information on dolphins. We also haven’t had, I think, the adequate tools to look at if language is embedded in their sound per se. So, now we have AI, we have machine learning, we have computers that can. I mean, they still need human help. But they can pull out patterns to look if there’s order and structure at least to these sound types.

Then you move into the — okay, well, to have a language, you have to have some structure we know that much. Now you have to interpret it. So, how do you interpret it? Maybe you have to do experiments to interpret it but you can also have things like meta data.

So, for example, if we’re recording a conversation with dolphins squawking and squeaking at each other, we usually know who’s there. We know their relationship. We know if they’re males or females. We know if it’s the mother or the calf. So, we have kind of — it’s a kind of an anthropological perspective on the society to be able to understand how they use maybe those structures and sequences. But that’s a whole other level. So, that’s kind of the next step once we get some detail to the order and structure of their sounds, then we can start trying to interpret it. If at all possible.

Miles O’Brien: What you’re talking about is the context of the communication to understand what might be communicated, right? You and I were having a conversation now and if you look at the video you don’t have no idea what we’re talking about, right?

Dr. Denise Herzing: That’s correct.

Miles O’Brien: So, it is possible they’re talking about Donald Trump or some random thing that has nothing to do with the seaweed or the fish or the humans there?

Dr. Denise Herzing: Sure, there’s going to be communication about what’s going on in real-time.

Let’s chase the fish. So I’m using my echolocation clicks. That’s the tool I use. I don’t have a fishing rod but I have my sound to dig out a fish. But then, there is the yeah, what are they talking about.

Sure, if you put a microphone at a human dinner table, you wouldn’t be talking about the food most of the time. You’d have munching sounds and swallowing sounds and clinking glasses but talking about what you did yesterday or what you want to do next week with the kids…that sort of thing.

So, there’s sound correlated with behavior that’s real-time action and then there’s what’s called context free grammar which the same sounds or sound sequences could be produced in different contexts, so it’s not dependent on if they are fishing. So, that’s kind of what you’re looking for are things outside of context we want to know both because we do both. You know, we’re going to talk about what we’re eating but we also want to talk about other things.

Miles O’Brien: So, the idea that you — I mean, as a start though, to be able to take 34 seasons worth of video. Put it into an artificial intelligence program. Pattern recognition, machine learning…at the end of the day, you’re going to come up with what? What are you hope to it get out of that you think?

Dr. Denise Herzing: I hope the first thing will get out of our machine learning work is, number one, categories of sounds that are hard for humans to categorize that might just be blowing past us, right? So, the computer can do that kind of stuff.

Then we’re going to look at the order of those categories of sounds to see if there is any grammar to them. Then you take those sequences and you go back to the underwater video, try to match them either with what’s going on or certain individuals with certain relationships. And then you’ll do your best to interpret it. Whether we’ll get to really understand if it’s language or not. I don’t know that’s — we could play back sequences for example. You’d probably have to do some experimental work to really confirm its language, that’s my guess.

Miles O’Brien: Do you have the sense of what we’re hearing is the core or is there something — you’re able to see stuff that the human ear can’t detect. Is there a whole other layer that we’re not hearing with the ear?

Dr. Denise Herzing: Well, there’s a lot of sounds they make within our hearing. However, when we use our high frequency recording equipment, we see components of those audible sounds up in those higher frequency ranges, so we’re certainly missing those with our ears but we have the tools to record them.

We also see indications of modulations of sound that could be some of the detail of what they’re communicating within the higher frequencies. I mean the reality is their best hearing is in the higher frequencies. So, it’s probably where they’re going to put most of their information or energy.

Other animals often have obvious communication signals with each other but if there is a predator around they also can switch into a stealth mode of communication. So, somehow they know that that predator can’t hear them or see them or whatever their communication mode is. And so, they’ll go into a secret mode with each other. So, again, these are the things we just don’t know about dolphins but we’re looking.
Miles O’Brien: What’s the next step on this research? Are you still kind of crunching all video and the audio and matching it all up? Is that where you are right now?

Dr. Denise Herzing: Yeah, I mean, we always do our basic stuff, field work, who is there, what spots they have, do they have new calves, who are they hanging out with and genetics. That’s the basic profile of the society work. And then, we continue to get sound and behavior samples in high frequency. But right now, yeah, we’ve got a 34-year database. We’re putting it all into some really cool pattern recognition exercises. We’re still kind of going through the exercise, so what works best.

What can we find from there? Yeah, that’s probably our focus for the next 10 years really is to mine that data and try to make sense of it.

Miles O’Brien: Oh, we’re talking decadal though? This is that much work.

Dr. Denise Herzing: Oh yeah.

Miles O’Brien: Yeah.

Dr. Denise Herzing: Well, you know and the tools are going to evolve and look how much they’ve evolved in the last 10 years. I mean, I wanted these tools 20 years ago but they weren’t around. But the data is there. So, you can always exorcise the data 20 years later.

Miles O’Brien: And this is all about your collaboration with Georgia Tech attack at that and everything else. And Google, et cetera. So, when we saw you last, one of the Holy Grail ideas is this box. Just walk us through a few of the challenges of trying to use the box as an interpreter as it were.

Dr. Denise Herzing: Well, I mean, there are two different ways we study their communication signals. Most of the time, we are just trying to decode, that means recording signals, processing them, looking at the patterns and try to interpret.

A second approach we’ve been trying which is a little trickier but it became obvious that it might be a creative way to interact with the animals is to try to do some two-way interface. So, this has been tried over the decades with limited success and challenging tools. It’s analogous to using a keyboard with a primate.

So, basically, what you’re doing is creating some artificial symbol. You’re matching it with a sound or an object and you’re trying to explore together with the other species what it means. So, if you and I were different species and I had my little coffee cup here and I said, “Hu, hu,” am I labeling this cup, am I saying would you like a drink, there are all these things. So, want a model the system. I’d ask somebody else or show them what the word for cup is in my language and then maybe you start a dialogue because you can both say the word for cup in the same way.

So, the idea with the chat system which are basically computers we wear in the water that have a very limited repertoire of artificial sounds that represent objects that the dolphins like to play with. So, we model with each other, so I have one or two order researchers with the same computer system on their body and we’ll ask each other for the objects using that system and they’re simple whistles and they’re probably easily mimicable by the dolphins. But we’re showing them what it gets them. If they make a whistle for the sound, we’ll offer them a toy or we’ll exchange a toy.

It’s not really training them. It’s modeling what is available to them with the system. And the hope is that and they’ve done, again, they’ve done this in captivity, quite a few different species, they can learn pretty readily to attach a sound type to an object and can use it fairly functionally. We know African grey parrots can do this. We know primates can do this, bonobos and common chimps.

So, it’s not too far to fetched to think dolphins might do this.

Now, whether wild dolphins want to do it or not is a whole other question because they have a quite interesting world without us. They’re not sitting at a tank looking for entertainment and human interaction.

So, we try to use what I call our windows of opportunities where there just playing with us. We try not to disturb their natural behavior when we have this system in the water but we’re trying to use windows where they’re dragging a piece of sargassum and we can label it acoustically while their doing that. We can offer it to them. We can ask them to give us sargassum but it’s challenging. Talk about challenging, you need to be working with the same individual dolphins. You need repeated exposures. This is why it’s hard.

I mean, a sanctuary system would be great. You’d have animals that maybe had time. There were in kind of restricted environment but that’s going to be their life and maybe they’d still be interested in working with humans. So, you might be able to exercise that system differently in a different scenario.

Miles O’Brien: I think the challenges of doing this to the wild are immense.

Dr. Denise Herzing: But you know what’s really cool is that, yeah, it’s challenging but we had actually quite a lot of time with a small group of individuals. Science often you find things you weren’t expecting. And so, sure enough, even though we didn’t have a lot of back and forth with the system like we had hoped, what we found embedded in the data, specifically the high frequency data, is a way that they were mimicking the signals that we had no idea they could even do.

That to me is like kind of a little – not a Rosetta Stone but a little indicator that maybe there is some other stuff in our data we haven’t been looking at because we kind of didn’t know that it existed.

So, in some ways, the tool of the two-way work has shown us how they prefer to communicate. Maybe they didn’t get the system or whatever. So now, we’re going to go back and look at our regular observational data and say, maybe they’ve been saying this stuff all the time in other ways.

Miles O’Brien: You just weren’t looking in the right place maybe or —

Dr. Denise Herzing: Yeah, basically. That to me is like really valuable.

Miles O’Brien: But building this box, there is a lot of technology — that’s a tough challenge on its own. In addition to the aspect to finding the individuals, teaching them, et cetera, et cetera.

Dr. Denise Herzing: Yeah, the technology honestly, it’s still really not good enough. It’s just a matter of – we’re not cabled to the boat, we don’t have Wi-Fi. We don’t have all the power and the storage and the amplification. We have to wear everything because we’re mobility swimming with the animals. So, that’s a whole other dance. If we were cabled to boat, we could just work there and have the computer behind us that’d be great. So, it’s all about mobility, modularity, smallness, but power. So, it’s been challenging for sure.

Miles O’Brien: Just to finish that up though. Do you have the sense that in the span of your career do you anticipate that there’ll be a breakthrough on this, that there’ll be some — is that impossible to predict?

Dr. Denise Herzing: I think we’ll have breakthroughs in the sense of getting more details out of what they’re saying. It might be for the next generation to take it to the next level with some other technology or analysis procedure. I mean, I’d be happy if we got the point of finding grammar and structure in their sounds and having a way to mine large datasets because that’s half the challenge. I mean, there are scientists that spend 30 years analyzing by hand animal sounds and the computers can do it with a little help more easily.

Miles O’Brien: Walkthrough a couple of the interesting things we saw together We saw mating rituals, right?

Dr. Denise Herzing: Yeah, this last week in the Bahamas was all about courtship and mating which happens.

It’s kind of pulsated. It’s a peak mating time.

So, basically, the ritual of mating involves a female that’s probably an estrous and somehow the males sense it. Probably chemically in the water is my guess, or maybe through sound if they’re scanning her. But clearly, she is the object of interest. The males, now remember they’re in coalitions of two, three, sometimes four and they’re going to either monopolize her from other males or in a larger group they’re just going to try to buzz her, get close to her. We often see them inverted upside down as one or two of them trying to get access to her. If the female is cooperative or interested, they’ll eventually get underneath her and they’ll mate. It’s pretty quick. They’ll take turns sometimes. They’re not monogamous, of course. They’ll take turns mating to get access to her and that goes on and on and on and whoever is the lucky guy gets to have a little offspring.

Also what we saw or juvenile groups doing that same kind of thing and remembering that they’re really not sexually mature at that point. The females get mature about nine or ten but the males take another five years to get mature. So, there’s a lot of practicing too, right? Learning to dance, it’s just – I’m sure it’s fun but it’s also practical in the sense that they’re learning their patterns, their habits, they’re getting used to each other in this whole process. So, we saw a lot that and a lot of sounds that go with it, yeah.

Miles O’Brien: Dolphins have sex or fun?

Dr. Denise Herzing: Dolphins have sex or fun. That’s proving they’re intelligent.

Miles O’Brien: So, we actually saw like the high school prom or something or the car afterwards, I guess.

Dr. Denise Herzing: Yeah.

Miles O’Brien: Anyway, all right.

Dr. Denise Herzing: Did everybody do that?

Miles O’Brien: We had a brief encounter with bottlenose. That was a little different experience in lot of ways. We talked a little bit about bottlenose but we saw them feeding in a little different way if you want to talk a little bit about that.

Dr. Denise Herzing: We saw the bottlenose dolphins doing different behaviors including feeding. Although all the dolphins on the sandbank feed in the bottom to a certain extent. The bottlenose they’re going for really deeply buried conger eels. Usually, there are fatty fish — it’s probably a lot of caloric value for the bigger bottlenose. So, we saw them doing it in called crater feeding and you probably heard there is a razor buzz. It’s basically echolocation clicks but it actually sounds like an electric razor.

So, the bottlenose scan on the bottom, just constantly going on clicking, clicking, clicking on the bottom and as soon as they either see some movement or a hole where the fish is living, they dig down and they really dig deep pushing up sand. Sometimes you see it coming out of their mouth and they finally got conger eel and they’ll pull it out and eat it. And then, they’ll do that again.

And on the bottom, we see all those different crater marks, we call it crater feeding because it leaves crater marks because the sand is kind of crusty and just is the way they dig. So, it looks like the moon escape. We can always tell if their creator feeding there.

Miles O’Brien: I imagine dolphin just kind of swimming through and catching fish that’s not how it works, is it?

Dr. Denise Herzing: Well, sandbanks. It’s a unique environment.

Miles O’Brien: All right. Any other behaviors that worth mentioning that we witnessed?

Dr. Denise Herzing: Some of the pretty obvious things we saw were dolphins making their signature whistles. So a signature whistle is a type of frequency modulated that’s unique to an individual. They’re basically like names. So, they’re broadcasting their identity or one dolphin can call the other really by its name.

We also saw a version of that that we call an excitement vocalization and that usually happens when the calves or sometimes juveniles or adults they get really excited and they kind of lose control of their motor system. They’re excited to see you, so they’ll swim around in the circle. It has partial components of a signature whistle but it’s like…They’re excited. They’re excited to see you. And that’s what they also do when they’re being rowdy and the mother has to discipline them. They’re trying to get them under control probably because it brings in predators or something.

Miles O’Brien: Do they get excited when they see you?

Dr. Denise Herzing: I sure hope so.

Miles O’Brien: Do they do that?

Dr. Denise Herzing: Yeah, I mean, they recognize us. They recognize the boat. Yeah, I think so.

Miles O’Brien: How would you describe your relationship with them? Is it a friendship, a bond, is it a — what is it? It’s among species, interspecies, how do you describe that?

Dr. Denise Herzing: Well, we’re probably the migrants. We’re seasonal migrants. We go out in the summer and study them. I think we’re kind of like social companions, pretty pathetic in the water but we try to be social companions. I think they’re just curious. I think intelligence recognizes other intelligence and curiosity is a component of — not only exploring your environment — being intelligent about it. I think they’re curious about other living things in the water and they know us. They probably recognize us by how we swim or what we look like or maybe by sound. Yeah, I think they’re curious about us. I think they have fun with us and they kind of ignore us sometimes when they’re doing their behavior. So, that’s really what you want. You want them to be comfortable but do their own thing.

Miles O’Brien: You do get the sense as they swim by you that they’re really checking you out. Is that me projecting or they really kind of —

Dr. Denise Herzing: No, they’re really checking you out and they probably — they get to know the subtleties pretty quick. How you swim, probably what you’re carrying. We’re always pointing cameras at them. So, they’re probably like what’s that thing. They’re really curious when we show them things too. Like if you dropped a fin the water they’d be like oh my gosh you’d like lost your tail. And they’re great, they’re great mimickers. I mean we have some hilarious footage of a person trying to mimic a dolphin kicking and then a dolphin behind that person kind of jerkily swimming. I guess they have a sense of humor.

Miles O’Brien: Making fun of the human.

Dr. Denise Herzing: Yeah. Well, they use mimicry in their own system. That’s how they learn and interact. So, for them it’s kind of natural. That’s really why we actually started the two-way system as they were mimicking us and look like trying to communicate.

So, we’re like let’s give them a tool, maybe it could go somewhere.

Miles O’Brien: So, if you could talk to them, what would you say?

Dr. Denise Herzing: I don’t know anymore. I think I’d love to know just kind of what’s important to them. I’m guessing it’s relationship and social stuff and I’m sure they have great stories about shark encounters in the deep ocean and all that stuff but what it’s like to be a dolphin would be kind of neat. So, we try to get as close as we can.

Miles O’Brien: Thank you, Denise, and thank you for dedicating your life and your career to such an interesting and worthwhile pursuit. I hope you crack the communication code soon, and I hope when you do, you tell the dolphins we’re sorry about how we treated their cousins and we hope to do better in the future.

All of this will be the subject of a TV story coming up on the PBS NewsHour–I’ll let you know when that’s coming down the pike. We’ve got a few other things in the pipeline for now.

And if you want to know always what we’re up to, I invite you to go to our website––and sign up for our newsletter. Once a week you’ll get a summary of science news, some of the interesting stories that caught our attention, and you’ll hear and see what we’ve been up to as well.

If you enjoyed this podcast, do us a favor: rate and review it. We’re just kind of poking along here, putting this out, seeing if anybody is interested. And the more you say how you feel about it, the better chance we get of getting a little traction and a few more listeners.

Thanks again for listening. I’m Miles O’Brien and this has been Miles To Go.

Banner image credit: Suzi Tobias.

Notify of
1 Comment
Oldest Most Voted
Inline Feedbacks
View all comments

Get our latest stories delivered to your inbox.