Aquatic Animal Tracking: The North Atlantic Right Whale

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Coastal communities are increasingly having to better understand the marine environment, including balancing prosperous fisheries and endangered aquatic species. It’s estimated that more than 90% of large oceanic fish have disappeared since the 1950s due to over exploitation, habitat destruction, and a changing climate. Listen to learn how the Ocean Tracking Network (OTN) became the world’s aquatic animal tracking network, deploying state-of-the-art ocean monitoring equipment around the world to inform conservation initiatives, including the protection of the North Atlantic Right Whale. 

Mission: Climate Change Adaptation & Resilience

Rhys Waters 0:00

Welcome to Beyond Research. A podcast brought to you by Research Nova Scotia.

Stefan Leslie 0:03

Coastal communities are increasingly having to better understand the environment, including violence and prosperous fisheries and endangered aquatic species.

Sara Iverson 0:17

It’s estimated that more than 90% of large oceanic fish have disappeared since 1950s due to over exploitation, habitat destruction and changing climate.

Stefan Leslie 0:29

This is Dr. Sarah Iverson, scientific director of the ocean Tracking Network, headquartered at Dalhousie University. Today, you’ll hear how this Nova Scotia based network has become the world’s aquatic animal Tracking Network, deploying state of the art ocean monitoring equipment around the world to inform conservation initiatives, policy development, and help monitor the health of the global ocean. Good afternoon, Sarah.

Sara Iverson 0:56

Good afternoon.

Stefan Leslie 0:57

Nice to see you.

Sara Iverson 0:57

Nice to see you. It’s good to be here.

Stefan Leslie 0:59

Part of the interesting thing about this podcast series is we get to sit down and talk to researchers and scientists who are engaged in these fascinating things in Nova Scotia where people wouldn’t necessarily have thought that they would be here but here we have an instance where Nova Scotia this institute in Nova Scotia is the global leader in this entire field. Can you tell me what the ocean Tracking Network does?

Sara Iverson 1:23

Sure, the ocean Tracking Network or OTN is a global aquatic research technology, data management and partnership platform that is aimed to transform the way that the ocean and its inland connected inland waters are viewed and understood, as well as the life that moves within them. As you have rightly said, aquatic animals are incredibly important to healthy ecosystems, which in turn provide immense economic and social benefits to mankind and to the world in which we live. But the world’s aquatic animals are under ever increasing pressure and many aquatic animal populations and important fisheries are really in dire straits. For example, it’s estimated that more than 90% of large oceanic fish have disappeared since 1950s. Due to over exploitation, habitat destruction, and changing climate, many fisheries have collapsed off of our coasts and certainly globally. And these anthropogenic impacts continue to alter populations, they alter habitats and habitat use movements, migration and survival, often in completely unknown ways. And they’re unknown, because trying to understand animals in their underwater world is just very challenging. And so OTN and OTN’s technology and their partnerships are about opening this black box. So OTN’s mission is to inform the sustainable use conservation and stewardship of aquatic animals by providing knowledge and turning it into policy and management change.

Stefan Leslie 3:04

And so when you say you operate globally, how many countries and how many species when give me a sense of how big this network is how big this Tracking Network is?

Sara Iverson 3:16

Well, we currently have deployed about 2000, OTN receivers, and I can explain what those are in a minute, globally. And we currently have at last estimate about 4500 users and collaborators and partners from 40 different countries. And we are button this is always ever growing and changing. And we are now tracking over 250 species and our database has now reached some 625 million detection records.

Stefan Leslie 3:48

So when you say 625 million detection records, every time one of your receivers, notes, the presence of an animal that you’re tracking, that’s a record?

Sara Iverson 4:00

That’s a record.

Stefan Leslie 4:02

And there’s 625 million times you’ve tracked an animal. You’ve got a ping on your system. So how do you actually track a fish or aquatic animal?

Sara Iverson 4:15

Well, there’s basically I always think of it as sort of three ways. There are there’s the fixed receiver arrays, and this is where acoustic receivers are placed along the ocean floor or fixed to stationary buoys or something like that. And then anytime an animal passes by that receiver, within a certain distance is then detected. That animal is tagged with an acoustic tag, and they can range in size from something that’s big enough to be carried by a large shark to something smaller than my little thumbnail that can be in a small salmon smolt and these receivers are usually across continental shelves. For instance, the Halifax line is the longest acoustic receiver line in the world, some 270 receivers and then but then the these animals have to pass by those receivers. And so that’s what I consider OTN’s sort of fixed platform. And then there’s OTN’s robotic tracking platform, which are autonomous vehicles. Gliders are OV’s, but particularly gliders, and we operate both Slocombe, electric gliders and wave gliders. And these basically are pre programmed to go wherever we want them to go in the ocean. And they carry a mini receiver. And so we can program them to go way off continental shelves in there, by tracking animals out that way. There’s also satellite tracking, and there’s any animal that’s big enough to carry either a satellite tag affixed to their pillage, or a pop up tag, can then carry a satellite tag. And this is important that they’re animals at surface, because then when they surface, all the data about where they’ve been, what they’ve been doing is then basically directly up linked to us orbiting satellites. And so that becomes real time information. And that’s very powerful. And then the, the other sort of tracking platform is what we call biological tracking platform or bio probes. And that’s where we have a unique type of acoustic tag called a vam co mobile transceiver, it acts as both a transmitter. So for instance, we are pilot project for developing bio probes were gray seals from sable Island, and you affix this, you glue the transceiver to their pelage. And anytime that CL passes in acoustic array, it’s recorded. But any time that seal comes within receiving distance of another tagged animal that’s recorded, and then we developed a Bluetooth link, where we put a satellite tag also on that gray seal. And when the animal surfaces, the Bluetooth connection, transfers all the data from that transceiver to the satellite tag up to the orbiting satellite, and then back to us in real time.

Stefan Leslie 7:19

So is this one of those things like so many things that’s getting faster, more complicated, or more capable, perhaps, and lighter as the years go by?

Sara Iverson 7:31

Oh, incredibly, I mean, that I think that’s the one thing is the technology is always changing, and it’s always getting better. We recently published a review article about the future of aquatic animal telemetry, and basically how once as battery sizes get more powerful and smaller, basically, we can make the tag smaller so that we can study more smaller either life stages or species. Certainly the kind of real time information which is becoming more and more critical, is also ever changing. And of course, these autonomous vehicles are just wonderful.

Stefan Leslie 8:06

Because it sounds like what you started with was relatively simple. If an animal passes by, you know that it was there, and then you got more sophisticated, and are able to tell more information about what it was doing before that as long as it came to the surface. And now with Bluetooth, you can tell proximity. So can you imagine where this is going next? I understand batteries getting smaller, and so on. But what might we be able to learn as this technology develops that we haven’t been able to to date?

Sara Iverson 8:35

Well, I think one of the big things that we think is really important is getting the data in more real time. Basically the way that fisheries have been managed historically, and currently are based on old data. We do trawl surveys or surveys of some kind. And it was maybe a year ago, it takes time to assimilate that data. We don’t know the effects of some of the fishing activities. But if we can get these data in real time, then we can be more agile in the way we manage fisheries. Knowing when populations are moving, or when they’re spawning when we should protect them when we should fish them all should create a more sustainable use of the ocean. We work very closely with Fisheries and Oceans or DFO to help support their mandate and missions. I think one of the more exciting efforts we have worked with both DFO World Wildlife Fund is using our gliders to track North Atlantic right whales.

Stefan Leslie 9:45

It’s been in the news over the past few years. So can you start by telling me about the importance of right whales?

Sara Iverson 9:51

Well, the Right Whale, basically was called the Right Whale back in the days of the whaling industry. It was the targeted whale for harvesting due to a number of factors, unfortunately, but even after the end of that harvesting happened, and they were essentially protected, they have continued to decline. And the North Atlantic Right Whale population is now one of the most critically endangered in the entire world, there’s probably less than 400 individuals. So it is really critical that we do whatever we can to prevent that species from extinction.

Stefan Leslie 10:33

And what do we know of the key risks to that population, there’s 400 individuals what’s likely to be the biggest threats?

Sara Iverson 10:41

Well, we know really, that the two biggest threats are shipping and fisheries entanglements. So basically, these animals are slow moving, they come to the surface, and they are struck by ships, those collisions are probably one of the biggest sources of mortality, but also they get entangled in fishing gear, primarily gear for lobster and crab fishing. And then they simply can’t swim or move. And they, that’s the other major source of mortality. And because these animals, they basically migrate far south in the winters, and then come back to Nova Scotia waters, where they have plankton rich waters to feed, and they are very susceptible when they are off our coast.

Stefan Leslie 11:31

So we have both ships, and we have fishing gear. So the value of tracking them is to understand the relationship between the presence of these key risk factors, and the critically endangered marine mammal.

Sara Iverson 11:45

Right to understand it, but to also in this case, actively prevent it. Because if we know that an individual is there, we can notify the shipping industry that please, you must go around this area, or you must slow to a certain speed. Or if you’re that big of a vessel, you have to be outside this area. Or if you’re setting fishing gear out that you need to remove it during this period of time, you know, that is maybe one of their key migration times. And then put it back when it’s safe to fish again. And that helps everybody because it does not look good to the world. If a right whale gets entangled in fishing gear. We have now seen right whales moving into the Gulf of St. Lawrence, and have established, you know, speeds that ships can go that’s that will, you know, help to prevent this kind of thing. And I think it’s a really tremendous effort.

Stefan Leslie 12:43

When you say in real time are very close to real time. What does that mean? Exactly? So we in you mentioned acoustic as well. So let’s start with the first part. When you say real time how soon after the whale is there do we actually know that it’s there?

Sara Iverson 12:57

Well, the gliders when they are at the surface, the data collected from the gliders is uploaded in real time to satellites. And then basically, when we have access to that data, the gliders are equipped with hydrophones that listen for whale calls, not just right whales, but other species as well. But because of the characteristics and nature of each of the species call, we can distinguish which species it is.

Stefan Leslie 13:23

So we are listening for the whales. And on the basis of what those gliders hear through the equipment on board. It can determine what species of whale is there.

Sara Iverson 13:34


Stefan Leslie 13:35

Wouldn’t it be easier just to tag the whales, you mentioned something as large as a seal, like you talked about gluing it onto a seal and something as small as your thumbnail. So wouldn’t it be simpler to attach something to the whale instead?

Sara Iverson 13:49

We very much wish that were the case. The problem is is that seals have fur, and you can epoxy tag to it. And basically that tag will stay on the seal until it molts the following year. So you know the animal is never going to carry that tag for its lifetime. You also in certain cases know you can get the tag itself back, for instance, when they returned to sable island to breed. But with cetaceans, whales dolphins, there’s nothing to affix to the skin. And, you know, people have tried things like little prong darts. But unfortunately, they don’t last very long and there’s concern for the animal.

Stefan Leslie 14:35

What did we do before we were able to listen for them? How else did we even know where right whales might have been?

Sara Iverson 14:43

Those would have been primarily through aerial surveys, possibly shipboard surveys. And aerial surveys certainly are still underway. But you know, there are times where the weather is inclement and that just doesn’t work and They’re very costly. The brilliant thing about the gliders is there is no ship time cost, there’s no carbon emission. Some of them are completely self propelled. And so we can send the gliders out in inclement weather, and in areas where we might not easily be able to get ships. So using the gliders is really quite effective. And then once the calls have been heard, then you could effectively use the aerial surveys without wasting a lot of time.

Stefan Leslie 15:35

It seems as well that there’s something about this that resonates with the public, people are interested in tracking the location of perhaps characteristic species, certain types of sharks or or turtles. So is there a public engagement component to this not just colleague to colleague in the scientific community, but working with the general public interested in this area?

Sara Iverson 15:57

Oh, yes, there’s a huge interest in the public and engaging the public, even in citizen science. And I think that’s always been a mission of OTN. And yeah, I think engaging people to understand that we tagged a great white shark off of South Africa. And within four months, it had gone over to Australia and back again, that tag to salmon smolts leaving rivers in Nova Scotia, ended up in Greenland. That gives people a real sense of the fact that aquatic animals don’t carry passports, they don’t recognize national or international boundaries. And if we don’t cooperate globally, we cannot manage sustainably the fisheries that we depend on.

Stefan Leslie 16:46

You mentioned that you’ve been working with DFO on the Right Whale and the interaction with the fisheries, butt how has that relationship gone internationally since this is a global network of that relationship between tracking of animals and the work that the OTN network and its full spread does, and the management side making decisions on economic activity, which is presumably very important to those communities?

Sara Iverson 17:12

Well, OTN has, for instance, partnered a lot with the Australians in trying to really track for instance, white sharks and educate the public about them. And you know, with the eye towards mitigating harmful conflicts between humans and sharks, to not consider something like culling sharks, which are already endangered and are critical to the health of the ecosystem, but instead to basically better understand them and be able to inform and predict movements and habitat use. So we can, you know, keep activity separate, and we can protect humans and sharks at the same time. We did a lot of work over the past few years with Arctic communities, and the Inuit communities to examine existing fisheries management practices, which for instance, in one case, the very highly valuable Greenland, turbot, or Greenland halibut, which is also known as a turbot was managed as two separate populations. And then through our tracking studies, we found and this was over a pretty broad area of the Arctic. And it turns out, they were all moving back and forth. And it was really one population. And we were able to change the management boundaries. We did some work with, for instance, with the lemon sharks in southern Florida, to really understand that some of the aggregations, the seasonal aggregations of these sharks, were the sharks were not local, they were coming from probably four or five different states that enabled us to better inform a management strategy. And you know, there are numerous examples like that.

Stefan Leslie 18:56

Sounds like there’s no end of projects and issues to which the OTN network could be applied.

Sara Iverson 19:03

No end in sight.

Stefan Leslie 19:04

And is this a matter of the ocean tracking, catching up to terrestrial tracking, is that we’re finally putting more attention on ocean species where perhaps, from the very early days of radio transmitter collars on land species, is this the ocean catching up? Finally?

Sara Iverson 19:23

I think so. I would say so because it’s difficult to study animals in the ocean, it has been a lot easier to to study terrestrial species. But I think both with animal handling techniques and development in that we have come a long way. And then in terms of developing the kinds of technology that we need to track these animals has really changed a lot.

Stefan Leslie 19:48

I can only imagine that the challenge of working in the marine environment is just that much more difficult, partly because you can’t ever see it. And it’s salty, and it’s cold and it’s dark, and so the technological challenges must be substantial.

Sara Iverson 20:03

Yes. And in fact that it doesn’t just stick with tracking ocean animals, you know, as we say we know more about the moon than we do about the ocean. So working with aquatic species is just that much more difficult.

Stefan Leslie 20:15

Sara, thank you very much.

Sara Iverson 20:16

Well, thank you. It’s been a pleasure to be here.

Stefan Leslie 20:20

I’ve been speaking with Dr. Sara Iverson, the scientific director of the Ocean Tracking Network.

Rhys Waters 20:29

To find out more about this podcast and the research featured in this episode, visit My name is Rhys Waters, and we will see you next time

Dr. Sara Iverson is the Scientific Director of the Ocean Tracking Network (OTN) headquartered at Dalhousie University. OTN is a global monitoring network, providing the scientific foundation for sustainable oceans management.