Are shark attacks sensationalised by the media, or have sharks acquired a taste for human flesh? Learn the truth with Melissa Márquez, the Mother of Sharks.
Sharks have earned a reputation in popular culture for being ‘blood thirsty people eaters’ but research and statistics show that this label is grossly misleading. In fact, up to 31 per cent of sharks face extinction, despite the important role they play in our ecosystems.
Tom and our new host, Amelia Searson, are joined by Melissa Cristina Márquez, a Latina marine biologist and conservationist. Melissa sorts fact from fiction and explains how we can better coexist with these cartilaginous fish.
Email thefutureof@curtin.edu.au.
Curtin University supports academic freedom of speech. The views expressed in The Future Of podcast may not reflect those of the university.
Music: OKAY by 13ounce Creative Commons — Attribution-ShareAlike 3.0 Unported — CC BY-SA 3.0 Music promoted by Audio Library
You can read the full transcript for the episode here.
Speaker 1:
00:00 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:
00:09 Hello again, I'm Tom Robinson.
Amelia Searson:
00:10 And I'm Amelia Searson.
Tom Robinson:
00:13 Before we get started today, I have some news. My studies at Curtin uni are coming to an end, and I'm taking the next step to work as a journalist in the Northern Territory. So this is my final episode of The Future Of. It's been a great experience meeting and chatting with Curtin experts and alumni. So I want to say thanks to everyone who's made it possible. And of course, a big thank you to everyone who's tuned into the podcast.
Tom Robinson:
00:35 I leave you in safe hands, though, with your new host Amelia Searson, how are you?
Amelia Searson:
00:38 I'm great, thank you.
Amelia Searson:
00:39 Definitely very excited to join the team. And, of course, congratulations for your new role.
Tom Robinson:
00:45 Thank you. So today, we're talking about sharks. Amelia, what do you think about that?
Amelia Searson:
00:50 I'm low-key obsessed with sharks. I never want to meet one, and at this stage, I'd never want to swim with one, but I'll definitely be sticking with the documentaries and Jaws movie marathons.
Tom Robinson:
01:00 As we were saying, a few episodes ago, we discussed one of the largest predators of the ocean, the killer whale. Today, we're exploring the orca's greatest rival and probably one of the most feared animals on the planet: the shark.
Tom Robinson:
01:12 With us today to tell us all about it is Curtin PhD student Melissa Márquez. Melissa is a marine biologist whose expertise in 'boneless fish' has earned her the title, The Mother Of Sharks. She's currently researching where sharks live and how the media's portrayal of sharks impacts conservation efforts.
Tom Robinson:
01:29 Melissa, I read recently that 2020 has seen the highest number of unprovoked shark fatalities in Australia since 1934. Do you have any thoughts on this?
Melissa Márquez:
01:39 Yeah, so the Australian shark attack file is reporting that there have been around 21 bites in Australia this year and 17 ... Or rather, they can be broken down into different categories, essentially. Some of them were fatal, which are seven bites. Eight of those were resulting in injuries, and six, there were no injuries sustained.
Melissa Márquez:
02:07 The one that seems to have risen the most, though, is the fatalities. Normally, over recent years, there have been typically one or two fatalities that make up a really small percentage of the 16 or so total bites that we annually get. And so lot of people are quite scared of this jump that we're seeing in this kind of fatality. I think, even though people want answers, the problem is that understanding how sharks and humans interact is a really challenging field. It's only going to continue to become more challenging as our world continues to change around us.
Melissa Márquez:
02:51 Not only is there climate change that we've got to think of and how that's changing sharks, but also how we are interacting with our ocean as well. There's more people, now more than ever, going to Australian beaches and enjoying our beautiful coastlines. But of course, that does mean you do have an elevated risk of having an encounter with a shark.
Melissa Márquez:
03:18 Of course, understanding how sharks and humans interact is very, very important. I think it's one of those things where, use the water with caution. What I mean by that is by following the rules that have been said before in regards to shark safety. So keeping an eye on the weather, making sure that you're not around any visible schools of bait fish, or birds diving, or possible whale carcasses. Just practice common sense, essentially.
Melissa Márquez:
03:51 It is something that a lot of us are trying to research, trying to figure out more of, but unfortunately, we're not going to have a clear-cut answer anytime soon because there are so many factors that go into play in something such as a shark bite.
Amelia Searson:
04:06 Before, we were talking about the previous episode where Tom interviewed about the orca. Melissa, in your opinion, who do you think rules the seas? Killer whales or sharks?
Melissa Márquez:
04:20 All right. Both great white sharks and orcas are fearsome top predators, but of these two massive animals, I definitely think that the killer whale is the ruler of our seas. No offence to sharks, but researchers have monitored great white sharks, seals, and orcas around California's Southeast Farallon Island. They actually found that every time orcas moved into this area, even just passing through the area, great white sharks actually vanished. Some didn't even return to the hunting grounds until the next season.
Melissa Márquez:
04:54 We're not 100 per cent sure why this happens, possibly because orcas target great whites as prey, or maybe they're bullying great white sharks over their shared prey source, which is seals. But it's really fascinating to see this.
Tom Robinson:
05:08 Talking about hunting habitats, or just habitats in general, where do sharks hang out and why do they choose these places?
Melissa Márquez:
05:16 Yeah, so sharks inhabit tropical, sub-tropical, temperate, and cold waters worldwide. They're found in a variety of habitats such as offshore and coastal areas, in pelagic, demersal reefs and estuarian environments, as well as freshwater bodies. Here in Australia we have a whole entire family, the Glyphis family of sharks that is just found in fresh water. Like many other animals, where they are depends on what they're doing. They might be hunting or are being hunted, they might be looking for another shark to mate with, or they may just be resting in some of these areas.
Amelia Searson:
05:54 Melissa, what role do sharks play in the ecosystem? Are they currently under threat?
Melissa Márquez:
06:00 Yeah. Sharks play a really important role in our oceans in a way that an average fish doesn't. But a lot of people think of sharks as apex predators, and that's not entirely true. Apex predators have been defined as a species that occupy the top trophic position in that community. Basically, they're noted to either one, have strong effects on trophic dynamics in a diversity of the systems there. Two, they affect the mesopredators, which I'll talk about in a second, via lethal encounters such as eating them. They influence the mesopredators' behaviour. And three, they also kill smaller predators for food to avoid competition.
Melissa Márquez:
06:42 By that definition, not all sharks are apex predators. Mature individual large sharks, such as tiger sharks and the great white sharks, are best described as an apex predator, but smaller sharks and young animals of these larger shark species are actually best described as, like I said earlier, those mesopredators. Basically that's any mid-ranking predator on a food web, regardless of their size or even their species.
Melissa Márquez:
07:09 So following that above criteria, most shark species and size classes are actually best described as a mesopredator. But regardless of the title that they have, they do have an impact on the environment that they're in. So depending on the species, they can help protect carbon stocks. They can modify their prey's behaviour, their morphology, their life history and physiology.
Melissa Márquez:
07:33 They can help cycle nutrients and allow for natural vegetation to flourish, and even engineer their own habitat, such as when they leave the carcass of a prey or even they themselves die, they create a temporary nutrient-rich habitat. Not to mention as well, they can also provide a bunch of bio inspiration as well as biomedical applications.
Melissa Márquez:
07:54 But unfortunately, they do face many threats, such as over-fishing and bycatch, climate change, pollution. And of course, shark finning. But, according to the IUCN, up to 31 per cent of sharks and rays are actually facing extinction. And almost half of all those known species are actually data-deficient, meaning we don't know enough about them to assess their extinction risk. We've got over 500 different species of sharks. Almost half of them, we don't know enough to actually say whether or not they are at risk of being extinct sometime soon. And 31 per cent of those over 500 different species are facing extinction. That's a huge problem for these animals.
Tom Robinson:
08:45 Obviously, conservation is a big part of working with sharks. Does the idea that all sharks are these dangerous, alpha predators affect that work? Does it make it harder to maintain their populations and work for the conservation of sharks?
Melissa Márquez:
09:00 Oh, 100 per cent! To put it bluntly, inaccurate and biased global media coverage is a huge threat to sustainable shark conservation. I'm not just saying that, research actually shows it. There's a new study led by Dr David Shiffman, who shows that not only does the popular press play a role in the public understanding of environmental issues, but that the shark conservation topics analysed by Shiffman and his team that were frequently covered by the media were usually biased, misleading or incorrect. That can actually contribute to the widespread public misunderstanding.
Melissa Márquez:
09:39 Not only do a bunch of threats face these animals, like the ones that I mentioned earlier, but they have to actually deal with the fact that they're being almost demonised, in a way. I'm sure you guys have probably even read titles that say, "mindless man-killers", "blood-thirsty", "rogue sharks", or even, "shark-infested waters", when really the oceans is their home. It's one of those things that how we talk about these animals really does matter, because if we keep using inflammatory language, it can be quite dangerous for these animals and their chances of being properly conserved and protected can be hurt.
Tom Robinson:
10:26 Something that attracts a lot of headlines here in Western Australia is drumline trials, and a drum line trial has been extended for another 12 months. Can you tell me how drumlines work? What are your thoughts on their effectiveness at protecting beachgoers? And does this tie into the moral panic that maybe surrounds sharks here in Western Australia?
Melissa Márquez:
10:47 Yeah. For those who don't know, a Western Australia's SMART Shark Drumline Trial has been ongoing since about February, 2019. And you're right, it will be extended by 12 months. It's called SMART S-M-A-R-T, because that's an acronym that stands for Shark Management Alert in Real Time. So that differs from regular drumlines in that a smart drumline is designed to send an alert to a drumline operator, and who that is exactly, I don't actually know currently, but when a shark essentially is captured on the line, that drumline operator gets that alert. So all the catch information, including the sharks caught and released is made publicly available.
Melissa Márquez:
11:31 Now you're probably wondering, wait, drumlines, haven't we done this before? We protested against these drumlines here in 2014. And your memory is good. Between January and April 2014, the former government used traditional drumlines, and those were designed to kill target species caught on the line. The SMART drumline trial, on the other hand, it's designed to catch, tag, relocate, and release these target species. And they're specifically targeting great white sharks, and gathering tagged shark movement data, which is going to be assessed to determine whether or not the SMART drumlines are reducing the risk of shark interactions under certain local conditions.
Melissa Márquez:
12:13 As a scientist, I think it's great to have an increase in the number of tagged sharks, because it's going to improve our knowledge on target and non-target sharks' small-scale and large-scale movements. Figuring out where the heck they are, where they're going. That's what my PhD is about, is habitat use of sharks. I think adding to the scientific understanding of the species is awesome. But using SMART drumlines for beach safety, I think using people as shark spotters, or technology like drones, and other non-invasive alternatives is a great way to keep our Western Australian beaches a bit safer.
Amelia Searson:
12:52 Melissa, what does a typical field day involve for you? Also have you swum with sharks, or have you even had any close encounters yourself?
Melissa Márquez:
13:04 Yeah, a typical field day actually really depends on when in the year you've caught me. If I'm out in the field, then I am definitely out with my drone, and I'm also with my baited remote underwater video camera set up, which is a fancy way of saying I've got a GoPro that has a little metal housing around it, and a treat bag at the end to entice sharks to come a little bit closer so I can take their picture and measure them.
Melissa Márquez:
13:30 What I'm essentially doing is hovering the drone over the baited remote underwater video camera to see if we are capturing all of the sharks in the area that I am seeing on that set up. Kind of filling in the holes, making sure that what we see is the whole entire picture, in a way. I'll be there for a few hours changing in between cameras and batteries as well.
Melissa Márquez:
14:00 Then most of the other time, I'll be behind my computer screen analysing those videos and analysing data as well as writing up the data. That's something I think a lot of people have a misconception of for marine biologists is that we're constantly out in the water and that's just not the case. Most of the time we are with our trusty laptops and computers to make sure we have all of our data to get that information out there. Because there's no point in doing research if other people don't know what the outcome of that research is.
Melissa Márquez:
14:33 I have swum with sharks. I do swim with sharks quite regularly. But I've never been bitten by a shark. In fact, my most, I guess, famous brush-up with an animal was a three meter American crocodile. About two years ago when I was filming with Shark Week, I got bit and dragged in the leg.
Amelia Searson:
14:55 Oh my God.
Tom Robinson:
14:57 Well, tell us more! What happened next?
Melissa Márquez:
15:00 So essentially it just held onto my leg, and this is actually similar to what a shark does, it's called an exploratory bite. I'll explain what that is. Essentially, imagine you're coming home and the person who you share a house with has made cookies and they're on the kitchen table, but they're either chocolate chip cookies, which you love, or they're oatmeal raisin cookies, which you hate. How are you going to figure out what kind of cookie it is? Well, usually you smell, you touch, and then you take a little bit of a bite. And that's what sharks and crocodiles sometimes do. They do that exploratory bite. Trying to figure out if something's food. But if you think about how easy our skin bleeds with a paper cut, you can realise why even an exploratory bite, such as a gentle bite to figure out what something is, can be so damaging to a person. Because their teeth are meant to cut through muscle, and bone, and sinew, and blubber, and even shells sometimes. Again, go back to seeing how easy it is for us to get cut with paper. No wonder we end up bleeding a lot.
Melissa Márquez:
16:09 Yeah, what it was doing was an exploratory bite, trying to figure out what the heck I was. Because I was in a wetsuit ... I don't know if you guys ever felt what a scuba diving wetsuit feels like?
Tom Robinson:
16:22 Yeah.
Melissa Márquez:
16:24 Yeah, okay. It has a really weird texture to it, and essentially their mouth is quite receptive to texture and to taste. It must have very much realised like, "Oh no, that's not meat. That's not what I normally eat." And on top of me keeping my legs still to make sure it wouldn't bite me even harder, it just spat me out. I guess I was very much the oatmeal raisin cookie for that crocodile! I was very lucky.
Tom Robinson:
16:52 Two questions. You knew not to move your leg when it had bitten you, so you were able to stay calm and stay still? And secondly, did you have any injuries, has your leg recovered?
Melissa Márquez:
17:08 Yeah, so answering the first question. I do know a bit about crocodiles, just because I grew up partly in Florida and we've got 'gators there, and so very closely related. I just love learning about predators in general. I'd always read up on all of these animals, and the death rolls are infamous, and in my head it kind of rolled, don't move your leg because it's either going to bite down harder and you're not going to be able to think properly, or you're going to go into a death roll and from your knee down, or your leg down, is going to pop off and you're going to bleed out before anyone can help you. That was what was going in my mind. Don't ask me how that was the train of thought that went through my mind, because I don't know ... Many people are like, "Could you do it again if you were in the same situation?" And I'm like, "I have no idea!"
Amelia Searson:
18:01 I think it definitely seems that crocodiles are the rulers, just from that little anecdote!
Melissa Márquez:
18:11 I don't really know how I did it, but I've talked to other people who've been bit by other animals like sharks, and they've told me that they've had the same exact experience where they go into this analytical mode of everything slowing down, and you're very much thinking, almost do a checklist in a way. But I was very lucky. I only got away with some puncture wounds of the teeth. It did drag me quite slowly, because again, it was doing that exploratory bite. I do have a pretty impressive jaw mark on the inside of my leg and a few puncture wounds on the outside as well, but it didn't rip or tear at any muscle, outside of obviously the puncture wounds from its teeth. I was back up and walking around by the end of 2018 and that happened at the beginning of 2018. All I've got now are some scars and the story.
Tom Robinson:
19:06 Yeah, wow.
Tom Robinson:
19:09 Well, despite that, you can tell that you still have a very positive attitude about your work and about predators. Where does that come from? Where does the interest in, particularly sharks obviously, come from? Do you have a favourite shark or underrated predator?
Melissa Márquez:
19:23 Yes. I'll answer the first question, which is where does my fascination with sharks come from? I think I've just always had this fascination with misunderstood predators. To me, sharks have always been one of the most misunderstood, if not the most misunderstood. It's, I guess, in my blood as well. I'm Hispanic and we have two last names, and my second last name is Villalobos, which if you translate it into English, actually is 'Village of the Wolves'. Well, sharks are sometimes called the wolves of the sea. Definitely seems like it was always in my blood.
Melissa Márquez:
20:00 I do have a favourite shark. It is the tiger shark, Galeocerdo Cuvier. They look just as they sound, they do have stripes on their sides, though they are not orange and white and black, they are grey and blue and a little bit green. And they're absolutely beautiful. I love them just because they're so charismatic. When you're diving with them, they have no concept of personal space whatsoever! They get up in your face trying to figure out what the heck you are. Their nickname is Trashcan of the Sea because they are not picky with what they eat. Their diet is usually fish and sometimes birds and sea turtles and whatnot, but in their stomach also found suits of armour and TNT and chicken wire and a porcupine. It's just weird stuff that you end up finding in their stomachs.
Tom Robinson:
20:56 As well as being a marine biologist, you also an advocate for women in STEM, particularly Latina women. Why is it so important that we have diversity in science?
Melissa Márquez:
21:07 Yeah, it was one of those things where I believe in the saying, "You can't be what you can't see." My introductions to sharks was actually the Discovery Channel Shark Week when I moved from Mexico over to the States, and I loved Shark Week. I love seeing all the sharks. But even from a young age, I never saw anyone that looked like me. There was never a Latina marine biologist. There was never a female marine biologist that I saw. From a young age, I picked that up. It was one of those things where I became really passionate in having that representation for everybody in the sciences, but specifically the field that I have an impact on, or can have an impact on. Which is the shark science field, which is why I did a TEDx talk all about it. It's titled Sharks and Female Scientists: More Alike Than You Think, and I talk about this lack of representation of female shark scientists in the media.
Melissa Márquez:
22:13 I think it's really important that growing up, both for kids, but also adults to be able to look up a line-up of scientists, a line-up of researchers, in whatever industry, and be able to see themselves because that harbors the inclusion part of science. We've got more diversity now in science than we had before. Great. But we're not being inclusive enough. We're not making the industry welcoming enough for people and allowing them to have the resources that they need in order to properly thrive.
Melissa Márquez:
22:48 One thing that I hear about is that women, or minorities, aren't interested in science. And that's not true. We are. We just sometimes don't have the resources in order to get to where science is a viable career, essentially. I try through all of the work that I've done, such as that TEDx talk, through different interviews, through my program, The Fins United Initiative, through the books I'm writing, through my podcast. I try to showcase these different diverse scientists, because I want people to be able to ... If they come across my profile or come across the work I've done and be like, "Oh, wait a minute. I see myself in bits and pieces of all of these scientists. I can make it, I can do that." I think it's really, really important to use the platform that I have to raise others up and be able to make this a more inclusive and diverse and welcoming industry. Because if you've got all of these people with different backgrounds tackling one problem, we're bound to be able to solve those problems a lot faster than if we were just tackling it at one angle.
Amelia Searson:
23:57 Yeah. That's fantastic. Of course, as you say, there are so many women who are interested in pursuing a career in science. And I'm sure even some of our listeners might be wanting to go down that path. Do you have any advice for people who are considering ... For women in particular who are considering a career in science?
Melissa Márquez:
24:16 Yeah. I think it's one of those things where you need to find a group of supportive friends who are going to be there with you through the highs and the lows. It's funny, because I remember growing up, my parents being like, "Don't talk to strangers online," and now some of my best friends are strangers online that I've never met in person, yet. Hopefully after COVID, I'd be able to meet all of them. But it's one of those things where if you have a community around you that supports your vision, your morals, is cheerleading you on when you're feeling really down, who gives you constructive criticism, who helps you out, who introduces you to their network and name drops you when they can. I think it's really, really important to, again, use each other's platforms to raise one another up and have each other's backs.
Melissa Márquez:
25:14 Find your niche, find your group is the biggest one. Because it does sometimes get lonely. It does sometimes get frustrating. But if the sciences is something that you were interested in pursuing as a career, go for it. Because honestly, I feel like scientists and researchers are some of the most passionate people I know, because they do this because they love it. They absolutely love it. They live and breathe it. For me, a lot of people were like, "Oh, do you ever get tired of your job?" And I'm like, "No. I live in breathe this stuff. This is the best thing ever. This is the dream for me." Yeah, I'm really lucky to have been able to get to where I am, but it's definitely not been without the help and support of many amazing people. So yeah, find your amazing people.
Amelia Searson:
25:59 Exactly. It's so important to have women represented in all careers and all fields, especially something as important as science.
Amelia Searson:
26:06 Melissa, thank you so much for taking the time to tell us all about sharks today … and crocodiles.
Melissa Márquez:
26:11 It’s my pleasure! Thank you so much for having me.
Amelia Searson:
26:15 You've been listening to The Future Of, a podcast powered by Curtin University. If you've had a close encounter with sharks, or have thoughts on drumlines, or anything else we've covered in today's episode, let us know. Send us an email at thefutureof@curtin.edu.au. If you love this episode, don't forget to share it and subscribe to our podcast.
Amelia Searson:
26:35 Bye for now.