Dr Simon Pierce - Whale sharks

Matt (00:04):

The podcast for the inquisitive diver. Hey, they dive buddies and welcome to the show. My next guest is a co-founder and principal scientist at the Marine megafauna foundation where he leads the global wealth shark research program and a science advisor to the global wealth shark photo identification database. He has recently co edited a textbook "Whalesharks: biology, ecology, and conservation", which will be available this coming August and has also been involved in the publication of over 50 scientific papers. Geekiness aside, Simon is not too shabby with a camera and co-hosts, a wildlife and travel photography gig called nature tripper, a website and magazine with his better half and conservation designer, Madeline Pierce, AKA Mad's. Oh, and it's all off. He's a Kiwi. So it's not only a brain box, but he's probably got a sense of humor too. Simon. Welcome to the show, buddy. How you doing?

Simon (00:56):

Thanks very much, man. It's great to be here.

Matt (00:59):

Did I get all that right?

Simon (01:01):

Yeah. No, that sounds good. Very flattering. Thank you.

Matt (01:04):

No dramas. It's a bit of a tongue twister. I want to try and get through it all.

Simon (01:09):

So much science so little time.

Matt (01:11):

I know. Right. Okay, well talking to science how, how did it all begin for you? How did you get into into the watery world?

Simon (01:23):

Well I learned to dive when I was at university and that was a bit of a game changer for me really. I was, I was already studying biology and I was very interested in conservation. But when I first started diving and snorkeling up in Vanuatu on a family holiday, I saw all these like kind of neon colored fish and just, you don't really see that amongst terrestrial life and New Zealand so much. So I was pretty blown away and then thought, well also after watching people go kind of crazy in the Bush for weeks on end the idea of like warm water Marine biology started sounding quite attractive to me really. So yeah, so I moved over to Australia and started studying the sharks and rays. And that's where I became really good friends with Andrea Marshall and who was doing her PhD on manta rays. And we ended up co-founding this Marine megafauna foundation where we work on manta rays with Andrea in charge that, and me and charge the waleshark research program.

Matt (02:30):

Happy days. It's a small world. I've heard of Andrea Marshall through Anna flam when she used to come across to Thailand when I was working there. So she's on the manta bit. You're on the whale shark, but how long has it been going? When was it set up? Seems

Simon (02:45):

Like such a long time ago, but also just yesterday. Like, I mean, I first started working on whale sharks with Andrea over in Mozambique in 2005. So I was doing my PhD in Brisbane at the time on some of the sharks and rays found up here and then yeah, she kind of, well, she was like, it'd be quite good to have a dive buddy. And also there's, there's lots of interesting stuff to check out over here. So I thought that sounded like, yeah, pretty interesting opportunity. I'd never been to Africa before I was, I kind of thought I was going to get like jumped by lions soon as I got off the plane or something, but nevertheless like checked it out and yeah, it really is a pretty amazing place and the whale sharks just blew me away. Yeah.

Matt (03:31):

And have you always had a love for the whale sharks? So is that just something that's progressed through time in the water?

Simon (03:37):

It's definitely developed actually. So it was coming from New Zealand where we've got lots of endangered species and things, but also a lot of really good work going on in terms of conservation. I was, I was kind of drawn to some of the stuff that people weren't really paying much attention to things like lizards and stuff. And then a lot of my PhD ended up being on stingrays because I realized there was nothing known about them and they were, they were really under threat. So then whale sharks, this big iconic charismatic species and our site, well, I don't really care. Like, I mean, surely we know everything about these animals. Like that's not, that's not somewhere where that, that I'm interested in. Like I can't help. But then when, when I started looking into it just pretty much to humor, Andrea I realized that actually, like there wasn't much known about them and there was still some good sized fisheries going on at that point. And I was like, these things are a bit screwed actually. So that's when I started really getting interested. So it was very much a like, because I was interested in conservation is my kind of primary thing. I was, I kind of think of myself as a bit of a problem solver. And when I realized that whale sharks were kind of a problem to be solved, that's what really got me interested. But when you start working with them, I mean, they're an amazing animal. So it's so yeah, I mean, I love them now. But there was definitely the problem that intrigued me initially.

Matt (05:07):

It was, it, it was the whaleshark that actually got me into the water. I was actually petrified of the water as a kid, but my dad called me down as a, I think I must've been about seven or eight years old and calm me down to see what was on the TV and as whale shark and I was just completely mispriced. But like you say, there's so little that we still don't know about him.

Simon (05:26):

Yeah, for sure and I mean, it's so awesome with, I think it's, it's something you don't really get on land with. You can be so close to such a large animal, but in complete safety, like they really are such an amazing ambassador for Marine life in general.

Matt (05:41):

Yeah. I, the big softies and then yeah, I had, I'm actually just thinking saying about softies. We had an incident a few years ago in Thailand where one was literally being puppy on the water and it was, it was chasing divers and we thought it was, you know, trying to nudge divers out the way to exit and go in a direction, but it would stop and turn around and come back. And it was just nudging divers for about 20, 25 minutes. And it was literally like an underwater puppy, but four meters long,

Simon (06:16):

I get you yeah. Big thought for you. But yeah, that's super cute. I like to get that sense. I think especially sometimes when you're running into sharks that haven't seen people before and not just obsessed. It's so awesome. It's a lot. It's really good for photography.

Matt (06:31):

Oh yeah so the research that you're doing with the animals, I've, I've done a bit of Facebook stalking and looking through your Twitter and all that kind of thing. Can you talk us through some of the stuff that you do? Like I notice that there's tagging going on and ultrasound and all sorts of scientificky kind of stuff. What's it all about?

Simon (06:58):

I mean, it's still all about the conservation for me. So we did a global conservation assessment of the species back in 2016 and we found that actually more than half of the world's population had been killed off since the 1980s or so. So that really brought home how work there still is to do. And with the research we're doing, like sort of you alluded to before, there's still some pretty big questions around their biology and things, but also just how many of them are left. But one of the really cool things about whale sharks, this is like I said before, you can get close to them and complete safety. There are some good places like Thailand where you can be in the water with them fairly regularly and it makes them a really good species to kind of try or some of these non-invasive techniques. Um so we can learn more about them without actually disturbing them. And it's, it's, it's a pretty cool evolution because when I started working on whale sharks back in 2005, right. I remember my PhD supervisor at the time, he was just like, well, you know, you're going to have to kill a couple. Right. And I was like what ed is going to well, yeah. I mean, you can't really research them unless you're able to like dissect them and things like that. And I like, well, you know, don't get away with people seem to have some stuff going on. Is I I don't know about what that, what they're up to. So I thought, well, I'm going to find out and found that with the, like with the dolphins and whales and things, they were often using things like photographic identification where you can tell individuals apart by sort of characteristic markings and things like that like the flukes on like the tails on, on humpback whales or the fins markes kind of cuts and things on, on dolphins and stuff. And I was like, well, you know what, whale sharks are a really good candidate for that kind of work because we can distinguish them using their, their characteristic kind of what sports is as sort of a fingerprint for each one. And and yeah, it's just kind of like, we started trying to work with them underwater and, and then try and do things like work at how big they were. So we started using things like lasers on a camera, so we could try and wait, so we could project lasers points onto them and see helping they were and things. And we're just keep on trying to find out more and more about them without, without disturbing them really. And it's been really cool to, yeah. Uh recently, as you said, there's I, it was actually some colleagues that were in aquarium up in Okinawa and that has pioneered a waterproof ultrasound unit. And they've been able to try that on a few species up there, like manta rays and also they've got a Whaleshark up there. And then yeah, so they joined us in the field, out in the Galapagos to try and use it out there for the first time. So that was definitely an exciting project to be part of. And we've now worked out how to take blood samples from them when they're swimming around kind of unrestrained and things as well. So it is pretty cool to try and push the boundaries of what we can achieve and, and hopefully that's what we're already seeing with some of the techniques that it's kind of filtering down to some of the other species that even less is known about.

Matt (10:17):

So was it just going back a step? Is it you guys that, that narrowed down the spot markings to identify the whale sharks? Because I've always been told that we should try and photograph the left-hand side just above the pectoral fins.

Simon (10:32):

Yeah. So there was a, actually a medical doctor that was working over in Western Australia in Exmouth, and he was the first person to, to really pioneer kind of field field research on whale sharks back in the 1980s. And he was certainly the fist one that kind of raised the possibility of identifying them by these spots and sort of started that project over there. And then there was one of the guy, Brett Norman. Who's also from WA he did his masters out there in the nineties and from that sort of trying to started trying to create more of a database. So I was one of the first people to get involved in that kind of global database. But like there's some, some very clever computer scientists and things that are heavily involved in that. So I'm kind of coming at it from the, the user side as opposed to the artificial intelligence side.

Matt (11:34):

Yeah. And is it similar to that the database or the, that the software that's used for recognizing the mantas?

Simon (11:42):

Same sort of concept? Yeah, there's actually these manta rays were a bit trickier because they, well, they don't have such sort of regular spots as a whale shark, and they've got like more blotches and things like that. And just a lot of things were more difficult with manta rays. So they're able to push sort of push the, the algorithms and stuff and, and develop that more. Cause there's so much interest in that sort of field for all sorts of things these days, like the like kind of using photography and all sorts of things, you know, facial recognition all sorts. So the computer science has really come along and actually just now we're starting to use then the algorithms they developed for mentors for whale sharks. And that's probably better than what we were using previously

Matt (12:34):

Happy days. And how big is this database gain then? Oh, it's

Simon (12:39):

Pretty incredible. Actually, this is how I since I've been involved, we went from less than a thousand sharks, almost all of which were from Western Australia to now. I think we're at around 13,000 sharks from I think, 50 plus countries. So it really is a global database now.

Matt (12:59):

Okay. what do we know from start to finish? Where are they born? What size are they when they're born? What depths are they born at and how far do they migrate? How long do they live? Where do they breed all of the above? Do you want to try and give an overall kind of lifestyle or a life span of a,

Simon (13:25):

No, because that would kill my job security to figure that stuff out. (hahahahaha) But no, it was interesting actually, because when we went through the, this you mentioned the textbook, so we've just been editing this textbook on what we do know about whalesharks. And it's amazing that we've got enough to fill a, quite a, quite a thumping book. But there are still some pretty big knowledge gaps there. And one of the kind of fun things I was involved in was trying to come up with like hypotheses on what the lifecycle might be. And there's like, so much of it is just waving my hands in the air based on like, pretty much based on where we don't see them. So like for instance, like say over in Western Australia, Ningaloo reef, most of the sharks, there are juvenile males and that's turned out to be a real cliche throughout the word, like Mozambique, where I was working initially and in places like Tanzania and Mexico and the Arabian region and the Philippines and all these other places and so all of these juveniles and, and Thailand as well, it's, it's all these juvenile males. It was just so, okay. Well, we seem to have, we can find these juvenile males but where are the risks of them? And, yeah. So hardly anyone has seen any wild shacks between like birth size, which is probably about kind of 50, 60 centimeters long. Okay. And, and then they disappear and well, we, we just don't see them. We don't see them when they're that size either. But then they start re-emerging at these kinds of coastal feeding areas at about three or four meters long seems to be the pattern. So that's, that's a very small way of shot to be like, even though it's nowhere near the best size like that, just off somewhere else at that point. And there's so many people in the water these days, you know, like between fishing and diving and people cruising around on boats that you would, if they were obvious, we would see them so I figured that living somewhere that is not obvious which most likely is kind of out in the open ocean or something and possibly not, not at the surface the whole time. So yeah, that's like, it's, it's very much a, we know where they're not because we don't really see them. So it's kind of trying to figure out, okay, where are the places where where we're not very good at looking? Cause obviously, you know, the open ocean stuff, I mean, that's the biggest habitat in the world but it's very difficult to study and because whale sharks, I mean, they won't take it bait or anything like that. So they just, they don't tend to get caught on things like long lines and that like a lot of other commercial caught species species are like sort of blues and makos and things that, again, like quite open ocean species, but we know a lot more about them. Yeah. So, yeah, there's plenty. There's plenty to unpack with that question unsurprisingly, but but yeah, in, in recent years we've been, I I've kind of been trying to focus in on a bit more about what the females are doing because with a very depleted population. And so, as I said earlier, those are the ones who like, we need, we need them to breed. We need more whale sharks. So it's the juvenile Male was it's like, it's, it's great to learn more about them, but that is not helping the species recover. We need to make sure we're like effectively protecting these especially the females that are kind of close to host to the size of adulthood, because those are the ones that have been through that, that, that time probably quite long period where they're small and probably quite vulnerable to natural predators and things and these, the ones that have got a long breeding life ahead of them. But we, we're just not very good at finding them so far. So we've we've identified a few places where we can see fairly large females on a fairly regular basis and they're all a long way off shore like way over the continental shelf places like the Northern Galapagos islands and, and sent Halina out on the med ed land to can and and some off shore sea mounts off Mexico. So we kind of figured that the adults are moving out into this open ocean because that's the only place we are seeing them. But yeah. So some pretty big gaps there.

Matt (17:54):

Well, do we know Cristina Zenato, she asked me a question to ask you seeing as she has a lot to do with sharks in The Bahamas. But she tends to see, obviously those sharks, those Caribbean sharks using their mangroves as a nursery to have any kind of idea on where well sharks would do this kind of nursery. Is it a, is it another one?

Simon (18:23):

That's an unknown. It's a super interesting question. And short answer is, I don't know. And the long answer is like, it's a really interesting don't know, I think so I've kind of found with some of the open ocean species, like blues and makos that they do use what we'd kind of define as nursery areas, but that pelagic nursery areas. So really quite large areas the open ocean where you're likely to find the little ones and a big part of that might be because like that kind of crappy bits of the ocean without much productivity. So there isn't much in the, there aren't too many larger predators that will try to eat them. Cause obviously that's a pretty big priority for a small shock is not getting eaten. So I've got my suspicions that the whalesharks might be doing something similar but almost completely without evidence um so I guess to give you some context on that, there's probably only been like maybe 40 baby whale sharks of less than a meter long or so that have ever been found in the wild. So, and they've been very scattered across the world, so we really don't know very much about them. But yeah, th that's my suspicion at the moment, like, ask me again tomorrow. I might give a different answer, but but I would not be surprised that they are using these what I'd call kind of a pelagic nursery area somewhere.

Matt (19:54):

Yeah. I suppose there's even possibilities that it could be constantly moving as well. I suppose I'm just sure. And

Simon (20:04):

I mean, oceanographic conditions that are going to really, I mean, it's a very dynamic environment out there. So yeah, for sure it might not be a very reliable place to go looking and I mean, baby whale sharks, like when you look at them, I mean, they've they've got a very like floppy kind of swimming motion and things. I mean, they look completely useless and so they're not, probably not very good swimmers when so I, I, I suspect they might be I mean that, that's probably not, not very good at swimming long distances, but basically plankton themselves. So yeah, certainly if there's like shifting kind of ocean currents and things going around that they're likely to get shifted with it.

Matt (20:47):

Yeah. Well, one of the questions I wanted to ask as well was your opinion on still going on the young wild sharks, but those locations around the world where locals feed that whale sharks and, you know, it helps tourism, et cetera, et cetera. But we see so many whale sharks, adult whale sharks that have severe scarring across their backs from where they've been hit by boats. And I can't help think that these incidences might have increased because the sharks are recognizing hulls as a source of food. Have you guys ever,

Simon (21:33):

I, I certainly think it's kind of the big controversy in whale sharks because this the kind of provisioning tourism as they refer to it, when people kind of feed them to habituate them to people and make sure they can get kind of up close and regular encounters and things. I think it's a nuance one. Like, I mean, there's no denying like how much money it brings into some of these at least previously impoverished communities in some really remote areas and, and people can, can certainly value the whale sharks more when they are tangibly with something to them. I think it depends a little bit on the, the area and stuff and how much it's done too, but like in general, I, I'm not I'm not a big fan of the practice. I think for me coming from again from the cons kind of conservation side of things, like they're an endangered species, and if we are going to be basically exploiting them for profit, it needs to be something in it for the species as well. So if some of these like places like Oslob, for instance, which is of course the largest largest over them, and you've got hundreds of thousands of people going to Cebu in the Philippines to see these shocks, it's one of the largest tours and attractions in the Philippines now, now, I mean that money isn't really going back into settling at whale shark conservation. So I think the missed opportunity, what some of these masters and sights with whale sharks is that they're like education and stuff that they give to the guests is not very good either. So you've got an opportunity with a place like that to create hundreds of thousands of ambassadors for, for whale sharks each year. And that has value for sure. Like, yeah, that, that would be a useful thing, but like, as, as far as I know the education hasn't really improved either since the last time I was there. So at the moment, like, I mean, I think there are bigger problems for Whalesharks than bad tourism, but it's certainly a very visible one. And it's one of the ways we have people are clearly profiting from the sharks. And I really think that more could be done to ensure that's more of a partnership between kind of humans and the sharks. They help them bounce back.

Matt (24:00):

Yeah, yeah. For sure. Well, let's, let's move on to the stuff that you guys do know. Or yeah. How, how do you, how do you track these guys? Cause they, you know, I'm not expecting that they travel freely all over the place or do they have migratory routes that you see them on regularly?

Simon (24:20):

Yeah. Well, we're still, we're still sort of trying to work that out, but but yeah, it's a really interesting problem because we have, because they do, I mean, they move a long way. I mean, they can easily do a hundred kilometers in a day and we're talking sort of ten, 20,000 kilometers a year. Even if they're not going very far, I mean that like in distance wise, they're constantly swimming, so they're covering a huge amount of ground. So basically like we can't follow them in boats that just moving too far and too fast. So we've had to use tags that can communicate with satellites so that we can retrieve the data from the remotely. But there we are at we've run into the technological limitation and that we, we don't have tags at the stage that can communicate through water and air so we either have to have like a receiving station underwater and collect information from the tanks underwater, or we've got to get them up into the ear somehow. So so one way we've been doing that is using is putting tags on the top of their dorsal fins. Just now like on little kind of clamps that, that are sort of designed to last for a few months. And then each time the shark comes up near the surface if there's a satellite, the correct type of satellite overhead then we'll get like a ping of where our shock is that day. So that's a really good way to, to see where they're going. The problem is that sometimes like they, they won't come to the surface for a month or so, like at least long enough for the, the tag to be able to communicate with a satellite so the other kind of tag we've been using as these, what we call archival tags and that designed to just stay on the shark record data. And usually we set them for about six months or so, and then they've got a little electronic release and they fall off the shark. They float up to the surface and then when they're floating on the surface, they can then upload the data to the satellite. So from them, we get, we get really good information on like it and things that the sharks swimming at. And, but quite rough information on where they're swimming because rather than getting like a GPS track where it's trying to reconstruct the movement based on time of sunrise and sunset and when the sun is like midday time. So especially in the tropics, that's quite tough because you don't get that variation and failings um but yeah, it's like, it's kind of been a combination of the two types really. So w we've definitely seen some places like the Galapagos. We've been doing a lot of tagging on adult female whale sharks, the really, really big ones. They do seem to have a, a pretty regular pattern of movement. Like we suspect that hitting out into what for them is kind of a feeding area at, and the Eastern Pacific where there's a lot of currents meeting and it's very productive area. And then often that cruising back towards the south American mainland, but not usually staying in like a few hundred meters of water, like that's still a reasonable way off shore but again, very productive area. So they seem to have a bit of a sick, they do. But the problem for us is getting tags to stay on for more than a few months. So it's pretty hard to see like with that during kind of an annual loop on a, a larger timescale or something like that, we only really get a snapshot. I know

Matt (27:59):

You're going back. Are you going back to the Galapagos next year?

Simon (28:02):

Next year. Yes. yeah. And so obviously things have been pretty interrupted over the last 18 months or so but since the start of last year but yeah, hopefully, hopefully things are normalizing next year, but it's really good on that. Like the, the team we work with over in the Galapagos mostly Ecuador based and they will be getting out again next month. So, so that's really cool. I'm sad that I won't be with them but it's great that the work can continue.

Matt (28:30):

Yeah. I'm not much the same. I push my back as well, but I'll even take the plunge and I've completely scrapped off the idea of next year and pushed it to 2023.

Simon (28:42):

Yeah. It's pretty difficult to plan ahead at the moment.

Matt (28:44):

What are you doing at the moment then you must be climbing the walls.

Simon (28:50):

Well, it's, well, I've of, I've been over in New Zealand for, up until last month and it was actually, I hit that, that textbook, I mentioned before that was well overdue. The publisher had been very very patient but last year I really had no excuse rather than to, to get onto that. So yeah, it was actually it ended up being kind of good timing and that, like, I couldn't travel, so I had no excuse not to work on it, but but also lots of people around the world that I work with were kind of in the same metaphorical boats. So there was lots of people going through their old data and publishing it and things. And, and like, we learned a lot about whale sharks last year. I was very happy to see the way the draft kind of early this year. And then, yeah. My, my wife and I are over here in Brisbane now and helping out some, some friends with some projects here in Australia. So it's yeah, good to get. It's been a long time between sharks for me. So it's been pretty good to get some diving and then places like Byron bay and stuff and, and start, start some projects down there.

Matt (30:00):

Yeah. Cause we, we first started talking when you were you're looking at the Wobbigongs.

Simon (30:08):

Yeah. So I was just trying to kind of get my head around what was being done at the moment. And my friend David that owns the sundive dive center at Byron bay. He did his PhD with me several years ago now. So now that he's in Australia, he was pretty keen to get some research going and he loves the leopard sharks. And I mean, everyone does, so just inherently of the species. So, and he was kind of like, well, why, you know, why don't you come hang out? And we can sort of brainstorm about other fun things to do. And like this, I mean, in Australia, you know, like on the east coast, for sure, I mean, what are we going? This is one of these things. There's, there's plenty of them. I mean, you see them diving all the time, but it's really not that much is known about them. Uh one of my friends did his PhD on them at the same time. I was kind of doing my PhD. And since then there hasn't been a, a great deal done since certainly in sort of like sort of central new south Wales up. So yeah, I was like, oh, that's quite interesting. And yeah, kind of having a look around for things to do. Well, I can't play with my whalesharks, but yeah, I bet. I mean, yeah, certainly some of the stuff over here is super interesting as well, so I'm quite into it at the moment.

Matt (31:20):

Oh, no pressure. Then you and David have got to get, get your heads together and come up with some serious data for when to get David on the show. We've already had a few emails back and forth, so he's got plenty to add. Yeah. Yeah. They can be our gurus on Julian rocks. Yeah. What, what do you know about the aggregation hotspots? Cause every now and then you get those real photos come up with loads of whale sharks in one area. Is it generally food that attracts them to the locations?

Simon (31:58):

Yes, always. Always. Yeah. I think of them as being like kind of the Labradors of the ocean, they're very highly food motivated. So most of the time when you see these shots of lots of whale sharks together on the surface, it tends to be a tuna spot. So there's the, the tuner all get together and spawn in a specific area. And then all these little eggs which are like very calorie dense, they're little kind of drops of oil and massive, massive quantities. They will float up to the surface. And and I mean that as like an absolute extravaganza for whale sharks. So it happens quite consistently off sort of conquering on the Atlantic coast of Mexico or kind of Caribbean Gulf of Mexico and off Qatar in the, in the Arabian Gulf as well, and very similar situation in both.

Speaker 3 (32:53):

And I mean, especially in Mexico, I mean, my suspicion is that wire shacks traveling from maybe thousands of kilometers around to take advantage of that. Like, I mean, there was some back of the envelope calculations done on their calorie intake. And it's, it was something like 43,000 kilocalories, which mean nothing to me. So I put it all in terms of chocolate and that's about eight kilograms of, of dairy milk chocolate per day. So there's, and a lot of the sharks are probably sticking around for a month or so. So I mean, they might not with that kind of calorie load for like a cold-blooded animal. They might not even need to feed much again, like for the rest of the year. So that's where with a well-worth sort of homing in on for them. So that that's when your team to get the big numbers together where there's, where there's a really where there's a lot of food for them. A lot of calories.

Matt (33:49):

8 kilos! Yes, I can, I can eat a lot of chocolate. I was just thinking the same on the, on the serious bits then endangerment we all know that the sharks, well, literally every shark in the bloody war is endangered, but how severe is the well sharks counts at the moment? And what's been done about it.

Simon (34:19):

Yeah. Well, I mean, whale sharks probably more severe than most they have, I gained like when we were sort of putting together information to, to get this book out we realized that they've got one of the cool, like the slowest life histories of any shark. So they probably don't become adults to about like 30 or 40 years old. And we don't know how old they get, but there's a good chance. It's kind of a hundred plus. So they really don't, but yeah, it takes them a long time to grow up. They're very slow growing and things. So, and when they, I mentioned before, like when they're small, they're probably got a lot of predators, but if the few that survive, that kind of period of their lives, it's, it's, I kind of like in the life history a little bit to like sea turtles that have loads of babies, only a few of them will survive, but if they do then they've probably got quite a long life ahead of them and whale sharks is similar, except people have started hunting them, like when they've got to a few meters long. So we're getting these tiny fraction of whale sharks that have managed to survive and then like just nailing them through fisheries. And, and you mentioned like boat strikes before, and that's probably one of the most significant threats now. So the problem has been that it's actually very difficult to monitor the numbers for us. We mostly been like, for instance, in Mozambique, like, I mean, I was working in one kind of area where we consistently, saw whalesharks, but I mean, whalesharks are super mobile, like, it's not like, like if the environment changes, they can just move by that they don't seem to do it, but I mean, these sharks are easily capable of just swimming over to Western Australia, if it's quite bitter over there for them so it's really difficult to disentangle like a, a true population decline or a recovery for that matter from just them shifting around. So that's kind of what we've been trying to tease out. So at the moment, though, based on what we like, all the kind of various bits of information, we were able to tie together yeah, we think that more than half of the population has been killed since commercial fisheries really started sort of back in the 1980s or so probably a little bit less than that. And the Atlantic ocean where there hasn't been the target fisheries but they have been like, there's been focused whale shark fisheries, and several countries and the Indian ocean and wisdom Pacific, and that's massively depleted the numbers.

Matt (36:56):

Yeah, I bet. Is it the usual suspects, the usual countries that live in this?

Simon (37:02):

Uh it's been. I mean, yes. Ultimately, I mean, a lot of the, a lot of the, there was demand for Fins and meat and things from China. And it was really interesting actually looking at some of the oldest stark literature and I mean, this international trade and, and whale shark fins has been going on since the earliest reference I found was I think 1907. So this has been happening for a long time, but I mean, it just really, really accelerated during the 1980s. So yeah, there was fisheries and Philippines and Taiwan and India and small fishery in the maldives that was probably more local. But like they, they kind of just ran out of shocks really, like, and I mean, you can, when you've got a shark that doesn't even become an adult or the maybe 40 years old, I mean, that happens, that happens very quickly so yeah, it wasn't some big kind of realization of how much we should sort of protect them in most countries. Unfortunately. it was more that it became an economic. So you asked though about what we are doing about it. And, and thankfully there is a lot of really good stuff going on now. So one of the good things, like as depressing as that exercise was for me of sort of trying to tie together all these like various accounts to end and working out that we'd lost more than half of them over the time that I'd been alive, that really, I think, helped mobilize people to, to start protecting them better. So once we realized they were like a endangered species globally based on the sort of quantitative criteria we see for there they were they were listed on the United nations convention on migratory species appendix one, which is kind of the closest thing we have really to international protection unfortunately it doesn't, it's not really legal protection. It's more like a, like a strong suggestion. So it's up to, it's up to countries now that have signed off on that, that they actually do have to protect the sharks and their own waters. So we're sort of working with a few different countries on that now. And like, it's, it's already leads to them being particularly Mozambique, which of course was a really cool thing for me, cause that's where I started. And hopefully soon and Madagascar, which is another whaleshark hotspot we know about now. And a few other different places too. So yeah, there's, I think the, the fisheries have really slowed down. There's still a lot of accidental catches of whale shirts going on. I suspect more than we've actually known about there's some huge gillnet fisheries that I, I didn't know very much about and the, and the Indian ocean and and sort of Western Pacific and there's like hundreds, I think thousands oh, actually I think it was in a couple of hundred thousand boats with knits up to about 30, 35 kilometers long going out targeting tuna and pelagics and things. And I mean, not like no one's taking any information about the bycatch but there's been some really good work done by some Pakistani researchers. And they've been like either training, some of the people work on the boats to collect data or also having, having their their research team going out on the boats. And I mean, there's certainly wild shacks being caught out there. And they estimated, I think that that fishery over the last few decades has caught over 4 million whales and dolphins in those areas. So that's like, I, I, I was not aware of the extent of these fisheries. And I think the issue now is also like, even though the targeted fisheries for whale sharks, might've stopped we know they're at a very low level, so other, other issues like ship strikes and that, which probably is pretty significant and, and even things like plastic ingestion and that these are all kind of cumulative impacts like they're not, they're not working in isolation. So that just piling on pressure on an already depleted population. So yeah, we really like it's, the protection is starting to happen and none too soon there is still plenty of work to be done and it is going to take them a long time to recover, I think as well. So yeah, we're just kind of working through like identifying the threats and working out how to, how to like practical solutions really. Yeah.

Matt (41:51):

So you mentioned that they get to adulthood about the age of 40 you know, round about my age, really, you know, sprightly is that when they reach sexual maturity or is it earlier than that?

Simon (42:05):

Yeah, so we think so we're trying to work it out. And we know like, it's, it's quite tricky to work out how all sharks are so a lot of species you know, like the trees, obviously you've got the rings and trees and they can kind of count the count, the bands and you can work out how old they are. And and that works in a similar way actually to a lot of sharks but whalesharks, same like I think they're a tricky one in that, like a tree, obviously can't move, you know, like in, in sort of temporate climes, they've got they've got a summer and they've got a winter and they're going to grow faster and they're gonna grow slower. Whereas the whalesharks that happens to like 26 degree water, if it gets cold, it can just swim over to where the water is warmer. Yeah, so we're still trying to kind of get our heads around that a bit. But yeah, best is as that it's about sort of 30 to 40 years old and about eight to nine meters and in males where we can actually, they've got like the only, only difference between them is that males have got a reproductive organ called a clasper that pokes out of their pelvic fins. So we've kind of got a sort of swim under that and disrespect their privacy for a moment. Butfemales unless like, we, we don't have a way to define if they're Adults or not, externally which is where the ultrasound is, is obviously proving pretty useful because we can see the internal development that's going on with them. So that's kind of a, I think the new frontier now. But, but I mean, we, it's, it's a cool technique and it'll be amazing to see, like one of the big questions is how often they, they have a litter of young. But I mean, we know that they are becoming adults at about 10 meters long also because the only pregnant female that's been examined was like 10.6 meters long. So at somewhere in that kind of, that kind of range. But yeah, so we're still trying to work out age though, but yeah, somewhere in that ballpark

Matt (44:19):

And what's I've got to ask, I have not asked it for a while. Being the title of the show is gonna be scuba the greatest of all time. Can you actually think of an individual dive that is your greatest of all time, or are they all kind of blended into one now?

Simon (44:39):

Well, I wouldn't go that far and there's certainly a few stand outs. There's there, I've had some pretty epic dives in the Galapagos say I work on the project up there. It is. And so it can be a bit unfair to other dive sites, I think when there's, when it's really on up there, just in terms of like, you've got thousands of hammerhead sharks and, and really gigantic whalesharks coming through and big yellow from tuna and silky sharks and black tip sharks and old us turtles. And that just that's it's. Yeah, it's pretty ridiculous. So I've definitely had some sort of standout guides up here and a couple of really good ones in Mozambique, I guess. There's yeah, my, I guess one that there's a little bit of a a specific one was a really interesting one for me was my exit into first solo dive over in Mozambique where we will work on a film crew we're working with a film crew shooting, a documentary on Andrea's work on the mantas. And the safety diver had forgotten most of his gear that was supposed to be my dive buddy. And I hit the install some equipment like, so they could, so they could film it, like they wanted to film a manta swimming past it. And and he was like, oh, it's fine. You know, I've only got one fin and 80 bar and no mask. I think I'll just hold onto the back of your tank and you can kind of kick me around. And I was like, well, as a safety diver, like, that's like, I, I mean, that's not very safe.

Matt (46:18):

He didn't get a salary, you didn't pay him for the day's work? Hahahaha

Simon (46:21):

Yeah. I heard it's like you had one job, buddy. Yeah, yeah, exactly. Yeah. so so I was like, well, I know this dive site. Well, like I'll just do it by myself. Like, you know, there's no worries at all. And went down with this equipment and was installing it and put it in and looked up. And it was a bloody, white shark swimming, passable,ucoming to check me out. And it was the first white shark I'd ever seen underwater. So I shit myself. Uthen,uand like the, I mean, it was, I was pretty deep, it was very murky and I'd just finished installing this equipment. So I was quite low on air. So I said, geez, you know, I've seen through this water column, like just rotating, like top trying to see what was around me and just a couple of meters visibility and,got back onto the surface and,add like yelled at, there was, we had three boats there, cause there were so many, the, the film, current things and like, my boat was a hundred away and I was just going to keep me on any boat, just sitting in the middle of it and it's just like, but, they almost the next day we went out again and I was like, I was still kind of buzzing from this whole encounter. And I mean, it's all in, it's all in your head, right? Like, I mean, it's not like the Shark tried to take me or anything like that. It was just kind of vaguely curious. Ubut like pretty that we went the next day and like the same thing happened again. And I had to dive by myself (joint laughing) in the same place. And I was just like, and I was kind of thinking about it. I was going, oh, like I'm myself here. And then I was like, well, actually, you know, what, if I hadn't looked up at that exact moment, I never would have seen the shark. So it would have been a completely normal day for me. Cause it's not like it did anything. It just swam past me. So if I just pretend that I never saw it, it's totally fine. And then, and for whatever reason that worked in my kind of easily amused brain. So,uso yeah, I was just like, yes, sweet as, I just did the dive. Didn't think about it twice. Umo yeah, that was definitely, ho, probably not my best dive, but like certainly one of my most memorable,

Matt (48:39):

No, that'll stay with you for a while. Yeah, for sure. I've yet to have the Whitey a moment. I'm sure it'll come. Yeah. Yeah. I've had a similar moment with a tiger shark. The first time I saw one of those, but I think the whitey, has gotta be the number one that's that gets your bum going,

Simon & Matt (49:00):

HAHAHAHAHA oh, bloody jaws.

Matt (49:05):

Well what, what can people who are listening in and reading your books and, and following you on social media or those kinds of things, what, what can they do to, is there anything they can do to help with the research that you guys are doing?

Simon (49:21):

Yeah, so, I mean, we've mentioned that global database. So one of the things that they've can do, if you have got any way of shot photos if you've had a chance to swim with them before, I mean, it's cool to get those submitted to the database uh some of the most, so that's a whaleshark.org, a fairly easy one to remember some of the most interesting sightings of coming from like what we call sort of citizen scientists like interested divers or, or just kind of people on the water with a camera and an interest. So we've had some whalesharks I think, fight from New Zealand now. And the longest distance reciting from Ningaloo reef in Western Australia one was picked up in Borneo by someone that just took a photo of a wave shot, cause it swam past his boat, which just happened to be at the right angle that we could actually identify it from that so that's a good one. If you go to Marine megafauna.org the Marine megafauna foundation's website, how you can adopt a whalesharks or sign up to our freemagazine as well ocean giants and that's, that's got all this stuff about yeah, I mean what we're up to and things on it. So that's where all our kind of new research results and things like that get released. So it's a pretty good way to stay up and, and learn about ways you can support the work that's going on and helping whalesharks as well.

Matt (50:47):

Yeah. I think there's a fair few people out there with photos of whalesharks, they can go rummage and stuff, flinging them into you. Hopefully.

Simon (50:54):

Well, the thing is, I mean, you know, when we think about how old whale shacks might be even really old photos some of the most interesting all photos are useful. But like, yeah. There's, if you've got like a, if you've, if you're an experienced diver and you've been diving for a while, or you've got like a dad or granddad or, or mom or grandmother it's been diving for, for decades then yeah. Definitely sought through there.

Matt (51:23):

Yeah. Especially if they used to wear red beanies and tight Speedos.

Simon (51:27):

Yeah. That's the way it'll come back in fashion

Simon & Matt (51:30):

Yeah, for sure. Hahahahahahaha

Matt (51:31):

I'll wait until you've done it first and then I'll contemplate it

Simon (51:34):

Yeah yeah, I'm not much of a trend setter. Hahahaha

Simon (51:38):

Happy Days, well Simon, I think we'll we'll wrap it up there. I think we've been going for around about an hour or so. Is there any points that you'd like to raise for anyone who's listening just before we go? How do people reach you?

Simon (51:53):

I really hope that Image of me in Speedos really sticks with you?

Matt (51:58):

Yeah. Well, you're in Australia. You've got to buy some budgie smugglers.

Simon (52:03):

When in Rome, haha

Matt (52:05):

Happy days. Simon, it's been an absolute pleasure dude. And,I look forward to you coming back on the show at sometime in the future.

Simon (52:12):

Thanks very much for having me, my pleasure.

Matt (52:14):

Thanks everybody. Bye-Bye

New Speaker (52:20):

The podcast for the inquisitive diver.