The apex predator of the ocean is not the shark, but the killer whale. Discover how these fascinating mammals use unique communication strategies to hunt, navigate, socialise and ultimately rule the seas.
Killer whales are at once both fascinating and fearsome, and Dr Wellard has dedicated the past 10 years of her research career to learning more about these mammals. In this episode, Dr Wellard reveals some of key characteristics and behaviours of orcas, such as their ability to take on sharks and whether they really connect with humans.
She explains how killer whales use bioacoustics, including echolocation clicks and burst-pulse sounds, to navigate, hunt, communicate and socialise with other pod members.
Dr Wellard also reveals the habitats of killer whales, including the deep waters off the Western Australian coast, and how her research is expanding the scientific knowledge of killer whales, enabling stronger population monitoring and conversation efforts.
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You can read the full transcript for the episode here: https://thefutureof.simplecast.com/episodes/killer-whales/transcript.
Speaker 1:
This is The Future Of, where experts share their vision of the future and how their work is helping shape it for the better.
Tom Robinson:
00:10 Hello, I'm Tom Robinson. While some researchers are looking for intelligent life up in space, others like my guest today are looking for it under the sea. Dr Rebecca Wellard has spent the past two decades working with marine mammals, and her PhD project studies the communication patterns of one of the smartest apex predators in the world - the killer whale. By understanding the unique communications of killer whales, we may discover the key to protecting them and other marine life as well. Thanks for coming in today, Rebecca.
Dr Rebecca Wellard:
00:39 Thanks for having me, Tom. Good to be here.
Tom Robinson:
00:41 I've got to be honest, before today I didn't know the difference between a killer whale and an orca, or if there was a difference. So could you explain that to the listener?
Dr Rebecca Wellard:
00:49 That's a very common comment that we get. We actually have a lot of people on social media who yell at us and tell us we shouldn't call them killer whales. So killer whale is the generic, the general name. It was actually termed 'whale killer' back in the day when the fishermen used to see this animal, and of course they used to hunt whales. But over time, that name's flipped around, and that's where we get killer whale. And their scientific Latin name is Orcinus orca. So orca is obviously, you got the genus and the species, and that may change over the time as we do more genetic studies on them. But for now, that's what it's at. So you can call them both, killer whale or orca, whatever you prefer.
Tom Robinson:
1:26 Are they whales, or?
Dr Rebecca Wellard:
01:27 They are the largest dolphin of the dolphin family. They are a toothed whale, as all dolphins are. But yeah, they're essentially a dolphin, a very big friendly dolphin.
Tom Robinson:
01:38 So obviously you study their communication. How do killer whales talk to each other?
Dr Rebecca Wellard:
01:44 So killer whales can be very vocal, and they have this unique dialect, so like a culture. So if we're talking in human terms, it's more like an accent rather than a language. So if I'm speaking English in my Australian accent, in comparison to someone speaking from Trump land, so from America, you can hear the difference there. Killer whales, like other dolphins, have three types of vocalisations. So they have echolocation, and that's the sonar. So they look at it to navigate, to search for food. It's essentially what our military sonar has been modelled upon, dolphin sonar. And they also use whistles and burst-pulse sounds. And that's their social communication, that's what they talk to their family pod menders and other groups, through that as well.
Tom Robinson:
02:30 Could a killer whale talk to a dolphin, another dolphin in a way, from a separate species, or do they have completely different ways of communicating with each other?
Dr Rebecca Wellard:
02:39 So I guess, yeah. It can whistle, it can do burst-pulse sounds. And I'm not sure if they can understand each other, but there is evidence that they do understand that it's a killer whale in the area. So with the killer whales that predate upon marine mammals that can hear them, they generally, when they're hunting, they're silent, because they don't want to alert their prey to them. So yeah, other species can recognise those calls, that they are a killer whale. Whether they can understand them, as to whatever the killer whales are saying to each other, we don't even know what they're saying to each other. But they know well enough that, "Hey, that could be someone who's going to eat me or my family." So sometimes they'll make scarce once they hear the killer whale sounds.
Tom Robinson:
03:16 Yeah, yeah. So in a way it's like I can hear a dog barking, but I don't necessarily know what the dog is trying to say?
Dr Rebecca Wellard:
03:23 Exactly, unless you're my dog, and I know she's barking at me to take her for a walk or to throw the ball.
Tom Robinson:
03:27 Yeah, yeah! So what do they talk about, killer whales, when they're making these noises at each other?
Dr Rebecca Wellard:
03:34 Look, yeah, we can only speculate. So one way for the science to look into it is we can look at the calls they make, and look at what behaviour they're exhibiting at the same time. So which is how we know whistles and burst-pulse sounds, they'll do it in a group behaviour, a social behaviour. So are they telling each other, "Hey, there's food over here," or, "Hey, come rub your pec fin on my pec fin."? And, yeah. Look, we can only speculate, we haven't decoded their language. But yeah, assigning behaviour to certain calls is probably the best way to look at it scientifically.
Dr Rebecca Wellard:
04: 07 There is evidence in other cetaceans, so whales and dolphins, that they have these calls that alert the rest of the group that, "Hey, we're about to do a lunge feed together," or, "We're about to do a tail slap together," when they're feeding on fish and other prey. So there may be other small little things that are in their vocabulary that we just don't know yet.
Tom Robinson:
04:25 Are we far away, or are you far away rather from understanding their language, or is that a long way down the track?
Dr Rebecca Wellard:
04:33 I think that's a long way down the track. I don't know if we ever will be able to decode them, and maybe it's not like a language that we use, where we use nouns and verbs and adjectives. Maybe theirs is a bit more simple, or maybe it's more complex. I just don't think we'll ever know. Again, just listening to them and seeing what they're doing at that time and what the resulting call will end in for the rest of them doing, we can only speculate in that sense.
Tom Robinson:
04:59 We were just speaking before we started recording. We're obviously here in Western Australia at Curtin Uni, and as someone who's lived in WA my whole life, I had no idea we get killer whales in our waters. And I'd imagine most people from WA also didn't know that. I associate them with ice, personally. Tell me about that, tell me about WA's killer whales.
Dr Rebecca Wellard:
05:18 Yeah, it's pretty cool. So in Australia, killer whales have been seen in all Australian waters. And I'm actually from the east coast, I moved to the west coast for the killer whales. And in Western Australia, this is the most reliable spot to actually see killer whales in Australia. So we've got two main regions. One's off the south coast in the Bremer sub-basin, and one's off the north-west coast of Ningaloo. And they're two separate populations. And we're seeing these killer whales at two different times of the year. And the killer whales or the orca down in Bremer sub-basin, there are over 140 that I've catalogued. And they're there from January to April, we go out there and see them.
Dr Rebecca Wellard:
05:59 They may stay down there for the rest of the year, we're not sure. It's horrible weather during ... it's winter now, and it's pretty hard to get out in a boat in these big seas. So we think they stay down there. And then off the north-west shelf of Ningaloo, there's another population there. And we're seeing them during the winter months, which coincides with the humpback whale migration. So, yeah. Look, if you're in Australia or even the southern hemisphere, and you want to see killer whales, the sighting rate of seeing them off Bremer is 90 to 95 per cent during those summer months, which is huge. There's only a few other places in the world that you can guarantee to see killer whales at that sighting rate. So it's pretty special living here.
Dr Rebecca Wellard:
06:39 Oh! Another fun fact, because you say you grew up here in WA. Have you been to Rottnest?
Tom Robinson:
06:43 I have, yes.
Dr Rebecca Wellard:
06:44 Did you know we've got killer whales off Rottnest as well?
Tom Robinson:
06:45 I didn't know. No, not until today.
Dr Rebecca Wellard:
06:48 Yeah, so around September, October. And again, these are different individuals. So I'll go into how we identify them. But they're different ones to the animals that we've seen off Ningaloo, and the animals we've seen off Bremer. So I actually head out here from Perth during September and October to try see them here off Rottnest. I am yet to get them. A lot of the fishermen send in their sightings. Last season, I missed them by 30 minutes, and they were actually chasing and attacking a minke whale. I was just gutted to have missed it. But yeah. Look, yeah, we've got them here off Perth as well. And off, up and down the west coast, yeah, they're sighted, a lot from incidental sightings, or the lucky fishermen and lucky tour boats out there are sighting them.
Tom Robinson:
07: 29 Are they family groups in these different regions, or is it multiple ...? They're pods? Is it pods of killer whales?
Dr Rebecca Wellard:
07:36 Yeah, when you've got a known family group, they're pods. So definitely off Bremer, I know those family groups like my aunties and uncles back in Melbourne, because you learn to see who associates to each other, and who hangs out with each other all the time, and yeah, you learn to recognise them and know them. So you know which family groups there are. And sometimes, they'll all come together in Bremer. So we had 50 to 60 killer whales last season come together, so multiple family groups, to take down a blue whale. And that hadn't been seen before in Australia. So that was really cool to see all these different family groups work together.
Dr Rebecca Wellard:
08: 11 The family groups of the Ningaloo do the same. They travel around in their family groups predating upon young juicy humpback calves. The ones here off Rottnest, we don't know enough yet. So hopefully, watch this space. In a few years, I can tell you who they are.
Tom Robinson:
08:26 Yeah. In terms of the hunting, something I heard, I just remembered just now, something I heard about the hunting habits, I suppose, of killer whales, is that they actually hunt great white sharks, some groups of them anyway, which to most people would sound terrifying, because most people are, you know, scared of great whites. Tell me about that, the hunting, or the nature of the killer whales hunting.
Dr Rebecca Wellard:
08:50 Yeah, I love that you brought up the great whites. So that's one of my facts I pull out to everyone, because everyone thinks the great white is the apex predator of the ocean. I'm like, "Nah-uh! The killer whale's right at the top there." So we actually had killer whales kill and attack great whites of Port Lincoln here in South Australia. And for months after that, the great white shark tourism, swim with tourism was decimated. They couldn't find any sharks, so they just left. And it happens off Africa as well. So, yeah. Look, they do have different hunting strategies and different prey specialisation as well, which makes killer whales is even more interesting to me.
Dr Rebecca Wellard:
09: 23 I touched on culture, and they have unique dialects per family groups and per regions. And then they also have this distinct foraging strategies and prey specialisations. So there's killer whales down on the ice in Antarctica that feed on just seals, they like eating seals. And there's some that feed on just whales. And then in the northern hemisphere, some just feed on fish, and prefer one type of fish. So they have different prey specialisations, but they also have different prey or feeding strategies. So I don't know if you've watched any BBC documentaries, and you've seen there's these seals on this ice floe in Antarctica, and they've got really scared faces on.
Dr Rebecca Wellard:
10:02 And that you can see a huge wave just coming at them. And underneath that wave is three or four killer whales lined up in a coordinated attack to push that seal off the ice floe so they can get it. Hunting strategies like that. And then even like beaching themselves to get pinnipeds like off the Argentinian coast. Yeah, there's these unique strategies. So here off WA, they have a unique strategy. The killer whales off Ningaloo that I was mentioning, they actually predate upon humpback neonates. And a neonate is a fancy scientific term for a baby newborn. So they'd prefer one- to three-day old humpback baby calves. They're nice and juicy, they haven't got much muscle on them, nice and fat for them. So they actually predate upon them.
Dr Rebecca Wellard:
10:46 And their family groups there, they each have their own role that we've seen. So one killer whale knows to go to the rostrum or the nose of the mother humpback. Another one knows to go to the side and distract her there. And then another one comes up the other side, and steals the humpback calf off it. So yeah, I've gone off on a complete tangent for you, telling you all about their feeding strategies. But yeah, they do have these unique feeding strategies.
Tom Robinson:
11:10 And it would be different from region to region, that strategy, compared to Argentina or Antarctica?
Dr Rebecca Wellard:
11:15 Yeah. So again, it's that culture. So they pass it down from generation to generation. Another fun fact for you. I'm just pumping it out for you today. Did you know killer whales go through menopause?
Tom Robinson:
11:27 I did not.
Dr Rebecca Wellard:
11:28 So not many animals in the animal kingdom actually go through menopause. Scientifically, as soon as we finish our reproductive life, so we can't produce offspring, we're deemed negligent, we're not really needed. But killer whales, and elephants, and pilot whales, and humans go through menopause. So the theory is after you've stopped reproducing, you don't need to hang around. But with these animals, and like us, we need to pass on the culture, and pass on those lessons, and teach the younger generation. So female killer whales can live up to about 80 years old, and they're a matriarchal society. So grandma rules the roost. The boys are so big, the killer whales, everyone thinks it's them that rule the Earth.
Dr Rebecca Wellard:
10:08 But it's actually the females, and then they pass on that knowledge and those feeding strategies that we're talking about down to the younger generations.
Tom Robinson:
12:15 I recently saw Blackfish, the documentary about killer whales. And the name itself killer whale probably lends to a bit of a stigma that they are dangerous killer animals. But as far as I'm aware, there's actually never been a human death as a result of a killer whale in the wild. They've all happened in captivity. What are your thoughts on that?
Dr Rebecca Wellard:
12:35 Yeah, that's correct. So killer whales have never harmed or killed a human in the wild. But yeah, in captivity, especially Tilikum, that individual killer whale that you're referring to in Blackfish, have yeah, injured and killed humans in captivity. And they're smart, intelligent animals, and I don't think they should be shoved into a bathtub, and kept away from the social interactions that they need. They're quite social animals, and they're quite family dependent as well. So to rip them from not only their conspecifics, so their friends, but from their family, I'd be pissed as well.
Tom Robinson:
13:11 Yes. The argument, I suppose, with zoos and captivity, some zoos do really good conservation work. Do killer whales need conserving? What are the population numbers like in the wild?
Dr Rebecca Wellard:
13:25 A hundred per cent they need conserving. So worldwide, killer whales are the most widespread mammal after humans. So they're found in every single ocean in the world. So we don't have a worldwide estimate for all the killer whales. So it's better to look at them per populations. And so in Australia, we're still not sure on the entire population here, the abundance estimate, because they are so hard for us to find here in Australia. But for an example, there are endangered populations. There is a population of killer whales called the Southern Residents, and they're down to, I think, 74 individuals. And that population is now critically endangered.
Dr Rebecca Wellard:
14:02 So when you're looking at conservation measures that need to be put in, you really need to assess it per region and per population to see how they're going. And for example, that population there, there's a lot of factors that are affecting that population, such as lack of food. They feed on salmon, especially Chinook salmon, they love, and there's not enough in the food system to keep them well fed. We're seeing 'peanut head', which is where a killer whale gets so skinny that their skull goes like that, zooms in like that, and gets really skinny there. And we're not seeing calves survive. So there's a huge pollutant load that's getting leached out into the calf through the milk. So toxicology. And they're also impacted by lots of ship noise and things.
Dr Rebecca Wellard:
14:45 So there are multiple factors that could be affecting populations. And when you look at how that population isn't surviving or thriving, you've really got to think about what are the factors that are affecting them, might be affecting our population here. Is our population also getting impacted by ship noise, or by food, by prey availability? And yeah, right now killer whales in Australia are actually considered data deficient. So that means we don't have enough information for them to assign a conservation listing. So my job here is not done. We've got so much more to learn from them. And yeah, I think conservation with every species needs to be considered, 100 per cent.
Tom Robinson:
15:25 How does your research apply to that conservation drive?
Dr Rebecca Wellard:
15:29 So with the research, we use all the data and the analysis and the results we find, and we can give them to policy makers, and help with the management policies, and try and manage these populations, so we can protect them. In 2017, I was involved in the board with the Australian parks to expand or convert the area of the Bremer killer whales. So where we were seeing them was called the Commonwealth Marine Reserve, and we wanted to get greater protection. So we ended up getting the Commonwealth Marine Reserve converted into a marine park. So there, that adds some protection. But the problem with that is it hasn't included the whole area that we're seeing the killer whales in.
Dr Rebecca Wellard:
16:09 So again, you can only do small things, and try build up and protect, and continue to do it more. But yeah, so far we've got the marine park, and we do need to expand that. So with all the data we're collecting and the results we're finding, you can push that through to the next level of policy management, and try get greater protection for the area, and for that species as well.
Tom Robinson:
16:28 What role does public awareness play in that? By that, I mean, I didn't know there were killer whales in WA until the start of this year. I bet there's a tonne of people around that don't know. So is that public awareness important as well?
Dr Rebecca Wellard:
16:42 A hundred per cent, a hundred per cent. I have a saying that, "Science isn't done until you've communicated it." So I've been very busy making people aware of the killer whales we have here, not only in Western Australia, but Australia. And it's not an uncommon thing that you're telling me now. A lot of people come up to me and go, "Oh, you're studying killer whale. Are you studying them in Canada, or are you studying them in Antarctica?" I'm like, "No, here in Australia." I'm the first person to do a PhD here in killer whales in Australia because they are so highly mobile and so hard to find. But with Western Australia, with the population we have off Bremer, for the last 10 years, we're getting consistent sightings. So it's provided a really good opportunity for us to study them.
Dr Rebecca Wellard:
17:26 And from that, getting people behind the cause. So telling people like you, "Hey, we've got these killer whales, we need to protect them," really helps us get the message out there. And then they, all the public helped us get the attention to convert this marine reserve into a marine park. I think there's power in people, and I think our job as scientists is to really get that message over to them.
Tom Robinson:
17:50 In terms of your work and your study, do you have a favourite experience or interaction with the killer whale in the field?
Dr Rebecca Wellard:
17:55 Oh, That's a good question. I think every day for me. There's certainly a few days that stand out, and you're like, "Man, that was hectic." We had the killer whales off the south coast in Bremer, we saw the first confirmed kill of a beaked whale. So beaked, they're these elusive, deep diving cetaceans that in Australia, we don't know too much about. They live in deep offshore waters. So the area we're working in goes down to 4,000 metres, it's pretty deep. And we had these killer whales with these little fin amongst them. We're like, "What is that? Is it a bottlenose dolphin?" And then we saw its head come out, and it's got this beak that is renowned for this species. And we're like, "Oh my God, it's a beaked whale."
Dr Rebecca Wellard:
18:38 And then they proceeded to kill it in under 30 seconds, and they peeled its skin like a banana. And I still remember they were throwing the flesh around, and I had blood on my pants, and I was just like, "This is hectic." And like that's an amazing day. But then I think about other days when we've got three family groups that I've known for ... how long have I been out there? Eight years, I've been out there with the killer whales off Bremer. And I see their new calves, and I know all the family members in there, and just to see them socialising and playing, and little head lunges, like their head popping out of the water.
Dr Rebecca Wellard:
19: 08 To me, that's just as a special day as it is to see the other day. It's just to see them thriving, and to see them socialising, and to see these animals that I've learned to study, to see the babies, the calves grow up. That's just as special for me. And then if I'm off Rottnest, man, if I just see them, I'll be stoked. If I just see a fin 10 kilometres in the distance, I'm like, "Yes! I've found them!"
Tom Robinson:
19:32 We've spoken a lot about, I suppose, culture and their language in a way, and there's a definite intelligence there to those animals. And I mentioned off air that I was in Exmouth recently, and you do the snorkelling and the diving and that kind of thing. And you always wonder when you see an animal in the wild, is it looking at you and understanding that this is, "Oh, that's a human, they don't belong here," but it's swimming around kind of thing? When you interact with these animals, do you think there's an understanding between you and the animal, or is it hard to tell?
Dr Rebecca Wellard:
20:01 I don't know if there's an understanding. I know there is a mutual interest. And the reason I say that is sometimes they'll come over to us, and they'll stay with us, and they'll bow, right? And they'll constantly look up and to see, "What are those weird things inside this metal thing?" And sometimes, I don't want to sound like a dolphin hugger, but you'll catch them eye-to-eye, and they just hold their eye with you. And you're like, "Damn, these guys are smart, there's something else going on behind there." And whether or not they understand what we are, or they just think we're these horrible other species on the planet that's polluting their environment, I don't know.
Dr Rebecca Wellard:
20:38 But yeah, I think there's definitely a huge sign of intelligence there, and I don't know if we'll ever really get the full understanding of just how intelligent they are when they live in a completely different aquatic world to us. We're just visitors in their home.
Tom Robinson:
20:53 In terms of those human interactions that not just you as a scientist have with animals, but everyday people as well, particularly tourists in places like Exmouth and the Ningaloo Reef, thousands of people go out looking for things like whale sharks. Is the noise pollution, the environmental pollution that comes with that a danger for your work and for these killer whale populations?
Dr Rebecca Wellard:
21:15 Yeah, definitely. There's a potential to disrupt the animal's behaviour and have an impact. So it has been proven in the northern hemisphere through a study that the killer whales were disturbed through noise, through both ships and tourist boats as well. So it's really mindful for everyone that's on the water, if they do get to see them, that they can respect them and give them their distance. There has been incidences in the region you're talking about, where people have been out searching for another species, but of course, the killer whales, everyone wants to see them. And they've unfortunately surrounded these killer whales whilst they're trying to undertake an attack on a humpback calf.
Dr Rebecca Wellard:
21:52 And it can really interrupt the whole process, not only the noise, but the presence of the boat as well, and if there's multiple ones there as well. So, these are really intelligent animals, and they need to be given their space to do what they're doing. So people need to be mindful of that, to not overcrowd them. I understand people can get super excited like me, but yeah, we need to respect them at the same time.
Tom Robinson:
22:12 I think part of the excitement with animals like this is the behaviour that they see. And so do killer whales ...? I'm literally thinking ... what's the movie, Free Willy, where he jumps over the kid?
Dr Rebecca Wellard:
22:23 Yeah, yeah, yeah. And the kid's got his hand up, and there's water.
Tom Robinson:
22:25 Is that real, or?
Dr Rebecca Wellard:
22:27 Look, I'm sure they were trained to do that. So there are other species that do a lot of breaching. So [inaudible 00:22:31], the humpback whales, they go up in the air, and they go slam back down. And there's a few theories as to why humpback whales breach. Are they getting parasites or an itch off them, or are they doing it to communicate with other humpbacks? So killer whales do some aerial activity. So we get breaching, spy hopping, just general jumping. When they're chasing something, they can, you know, porpoise, which is going super-fast through the water, up to like 20 knots. Yeah, that's crazy to see. But yeah, they do do the breaching as well. I've never been lucky like that little boy, like Free Willy, and had them jump over me, and put my arm up, and get showered in them.
Dr Rebecca Wellard:
23:06 But when they're breaching, like yeah, you take it in, and you appreciate it. But I'm usually behind my DSLR, my camera lens. And whilst everyone else is appreciating it, I'm trying to shoot where the genital area is, because that's how I can sex them as well, to look to see if they've got mammary slits, where a female secretes milk. So forever the scientist, sometimes you've got to put the camera down and appreciate it. But most of the time I'm like, "Oh, try get its genitals!"
Tom Robinson:
23:36 So what comes next for you and your research?
Dr Rebecca Wellard:
23:38 So I'm going to continue my research on the killer whales here. I've finished my PhD. Unfortunately my scholarship's out, nobody's paying me to continue it, but I will continue it on the side as much as I can. Yeah. Look, we're just scraping the surface of killer whale research here. There is so much to be done still. So the plan is the long goal for me, continue learning more about them so we can continue protecting them, working in collaboration with other universities and researchers, and essentially getting enough data, so we can remove that data deficient label that they have. Once we understand them more, then we can protect them. And they're the apex predator. It's not just them that we'd be protecting, we'd be protecting the entire ecosystem. So it's something that we should all look forward to, and everyone is welcome to join along the ride and help us get there.
Tom Robinson:
24:30 It sounds like there's a long way to go, but it's definitely a worthy cause. I think we'll leave it there. Thank you Rebecca, for sharing your knowledge on the topic.
Dr Rebecca Wellard:
24:36 Thanks so much, Tom. Thanks for having me.
Tom Robinson:
24:38 You've been listening to The Future Of, the podcast powered by Curtin University. If you have any questions about anything that we've raised today, you can get in touch by following the links in the show notes. Bye for now.