Nic Toki at Burwood Takahē centre
Image: Julie Harvey | DOC
The DOC Sounds of Science podcast is hosted by our Threatened Species Ambassador Nic Toki.
Nic interviews our conservation experts and scientists to bring you a deep dive into some of the work happening in the conservation space.
Nic’s mission as Threatened Species Ambassador is to raise awareness and inspire action for our threatened native plants and animals.
Telling the stories of New Zealand's native wildlife is her passion.
She loves getting people as excited about giant wētā as they are about kiwi or kākāpō.
Marine species expert Hannah Hendriks talks whale strandings, post-mortems and crucial data.
The birdsong at the start of this episode is the North Island robin.
Find out more:
Nic: Kia ora everybody, I'm Nic Toki. I'm the Department of Conservation's Threatened Species Ambassador. And I'm very proud to bring you this Sound of Science podcast.
Nic: The purpose of this podcast is that we want to tell you all the stories of our amazing scientists and technical experts out there looking after ‘the nature’, working with us to make sure that we know everything there is to know about our threatened species. Today I have the privilege of having my colleague, Hannah Hendriks, who's a Marine Species Support Officer from our Marine Team in the Department of Conservation. G’day, Hannah, how are you?
Hannah: I’m great thanks, Nic. How are you?
Nic: I'm very well. I thought it was a really good idea to talk to you now, at this time of year, because the topic of your work really is starting to bubble up again. So maybe if you could start by telling us a little bit about what you do and what's involved.
Hannah: Sure. So I provide national support for marine mammal incidents around the country, supporting our Rangers on the ground who are responding to strandings and things like that. I provide a link between DOC and researchers, coordinate our protocols and procedures that we follow, and manage the data that comes out of these events.
Nic: Strandings are always a hot topic, particularly in New Zealand, aren't they?
Hannah: They are.
Nic: We seem to get a lot of them. Do we get more in New Zealand than perhaps other countries get?
Hannah: We are a hotspot for marine mammal strandings. That's mostly because we just have so many species that come past our shores, whether they live around here or they migrate past us. We get about half the world's marine mammal species coming by New Zealand at some point.
Nic: What is it, do you think, about-- there's something about whales and dolphins, isn't there, that just makes people kind of ‘feel all the feels’. So, do you get caught up in people's emotional connection to what's going on, particularly with regard to strandings?
Hannah: Definitely. It can be hard for people to separate their emotions from the event. Obviously, whales might be making sounds on a beach or might look like they're crying. And yeah, people find it hard to detach themselves from reality in some of those situations.
Nic: Do we know much about why whales do strand?
Hannah: Short answer is, no, not really. It's really complicated. There are lots of different reasons why whales might strand. And it sort of depends on the species and where you are.
So dolphin species, like pilot whales, common dolphins, they might strand when they're looking for food. Say, there's orcas going by, and they're trying to get away from them. Or if there's places like Farewell Spit, that act like a natural whale trap.
And these gently shelving beaches like in Golden Bay, their echolocation might not work very well. And so they might not know that the water is getting shallower. And then they can be caught out when the tide disappears from underneath them, basically.
Nic: You've mentioned echolocation. Do you want to just explain a little bit more about what that is and why that becomes a problem?
Hannah: Yeah, so basically, they send these sound waves out from their heads. And they bounce off soft substrates. And they are received back by the whales or the dolphins. And they tell them basically what's in front of them.
Nic: So it's like sonar.
Nic: Same as what ships use.
Hannah: Yeah, just like sonar. So they can use those to tell where the shore is, or where food is, things like that. But when these really gently sloping beaches come along, they aren't going to be providing such a strong signal, especially when it's muddy or silty. And that can get them confused.
Nic: How big of a deal are strandings things from a conservation perspective for a species? And I suppose it varies species to species.
Hannah: It will definitely vary species to species. So with pilot whales in New Zealand, they're classified as not threatened. And these things have been happening for millennia. You know, these whales have been stranding on Farewell Spit for as long as we know. And so it's unlikely that they're going to have a big impact on the overall population size. And we haven't seen that as time has gone on.
Nic: And what are some of the other species that strand?
Hannah: Common dolphins, once again-- that's more mistakes being made or being forced up onto the beach from predators. So they can often be re-floated, which is great. Pygmy sperm whale is another really common one, which most people might not even know about. It's this small-toothed whale. They are often washed up in Mahia Peninsula.
And also beaked whales is another one that often washes up on our shores. We've got 13 species of beaked whales in New Zealand. And Gray's beaked whales are the most common ones to wash up around the country.
Nic: Whale standings are huge, right? They're a huge logistical--
Hannah: Definitely. Yeah, especially when you've got like 1,000 volunteers on hand, as well, that you've got to manage. There's a lot going on.
Nic: And so do you get involved in that?
Hannah: No,, not really. That's the lucky job of the Rangers on the ground. But I do just support the Rangers, so they know what protocols they need to follow, if there's any species-specific things. And as I said before, I might get them in touch with the researchers that might be interested in those species.
Nic: When whales do strand, and it becomes apparent that we can't get them back out to the water, and we've dealt with our grief about that, what kinds of scientific information do we want to collect to try and understand what's going on?
Hannah: Standard DOC protocol was to take a tissue sample. So that's basically just a small section of skin from each animal. And that goes into what's called the New Zealand Cetacean Tissues Archive, which is managed by Auckland University on behalf of the Department.
And so that's got samples of basically all the different species they have stranded on New Zealand's shores. There's like over 3,000 samples in there or something like that. It's pretty amazing.
And from that, we can get, obviously, genetics. So you can determine what species they are if it's not clear on the shore-- especially important for our beaked whale species, where there's 13 different ones. And to the untrained eye, you wouldn't know which one it is.
You can get gender. And you can get family relations. And then there's some people doing some work on trying to age them from DNA, as well, which would be pretty interesting.
So that's the standard sample we take. But in some cases with some species-- or depending on what researchers are focusing on-- we might get further samples or get the whole animal to Massey University or another research institute, for necropsy to examine what the cause of death is. So this happens with our Hector's and Māui dolphins, in particular.
DOC's got a contract with Massey University to get all of those animals examined, so we can learn more about why they might have died. Unfortunately, it is actually very hard to determine why things have died. And we may or may not actually get any useful information out of those.
Nic: Given that we've had this database for a long time, particularly for species like Hector's and Maui, do we have any kind of ideas that have come out from the data?
Hannah: Nic: Yeah, definitely so. With the genetics work in particular, we get things like the Māui dolphin abundance estimates. So we know how many there are. That's during mark-recapture work. And then with the necropsy stuff, we can find out if they're dying from certain diseases like toxoplasmosis and work on how we can potentially mitigate those sort of threats.
Nic: So it's a bit, kind of like CSI?
Hannah: [LAUGHING] A little bit. Not so glamorous. Not so fast, either.
Nic: [LAUGHING] Not so fast.
So given that it is summer and that people-- just to stray off the topic of strandings briefly, though-- let's talk about the Marine Mammal Protection Act.
Nic: So people are out and about. We've all crawled out from behind our computers and are hanging out at the beach-- for those of us that drive a desk like me. And so there's a lot more seeing dolphins and whales around and interacting with them.
Just generally, what are the rules so that people know how to behave? Because we know people get a bit like “wahh, Justin Bieber, whales, dolphins!” How could people behave that makes them legal?
Hannah: Yeah, so the Marine Mammal Protection regulations, which is under the Marine Mammals Protection Act, basically lays out some regulations that people should follow when they are around marine mammals. Particularly if you're on a boat, you need to give them space. 50 meters to whales is how far you need to stay away, no more than three boats in the vicinity, and you can't swim with whales.
Also, you're not supposed to drive drones 150 meters near a whale, which people often don't know about. And these are quite important to follow. Because it gives these dolphins or whales space to rest, feed, and socialize with each other.
Nic: And particularly if they're got babies with them, as well.
Hannah: Exactly. There are actually specific rules when they have babies with them.
Nic: OK. So it's essentially, just give them space.
Hannah: Give them lots of space, yeah. Don't disturb them. Don't stress them out. And you can cause them harm, and they can cause you harm.
Nic: So back to the beach back, back to the stranding, can whales-- or maybe dolphins-- but can whales cause people harm? If they come across a stranded whale, what are the things people need to do to keep themselves safe? Because you know, I've seen flippers, and tail flukes, and things sort of thrashing around. You wouldn't want to get sconed with one of them.
Hannah:Yeah. So the tail of a whale or a dolphin is very powerful. There's lots of muscles in there. And that can definitely cause you harm. so definitely, keeping a meter away from their tail is really important.
Also, obviously, all of these dolphins have teeth. And some of the whales have teeth. So keeping fingers away from mouths is really important, too.
Nic: Right. You don't want to accidentally get-- it'd be like getting your hand caught in a car door-- wouldn't it? -- with teeth. So people have a lot of theories. I've heard people talk about impacts of plastic, maybe climate change, maybe seismic stuff going on in the water. Can you talk us through what we know or don't know, what the evidence is on that stuff?
Hannah: Sure. So with regards to plastics, we actually have only had about one or two instances of finding macroplastics inside whales and dolphins.
Nic: What's macroplastic?
Hannah: Stuff that you can see with the naked eye, basically. So that's different to your microplastics, which is plastics that are broken down into really tiny pieces. And there is some work going on where people are looking into the blubber and stuff of whales and dolphins to see if they can figure out if that's affecting our whale and dolphin species in New Zealand.
Climate change is a big one-- quite hard to comment on. It's so hard to investigate these matters. But it's definitely possible that changes in the ocean temperatures will affect the food sources and all the sorts of things like that will have flow-on effects to these species.
Seismic surveying, definitely a big cause a concern for lots of people. So we do have a code of conduct for seismic survey companies that they need to follow to minimize those impacts on our species.
Nic: And so I presume we're collecting data as we go about what else is going on in the environment when we come across a stranding?
Hannah: Yeah, so each time there's a stranding, the Rangers will collect a range of data about the animal and the conditions. And they'll fill out a form. And it will go into our national database of strandings.
Nic: Sometimes when there's a stranding, even though there might be lots of people there to help, it doesn't go well. And we can't put them back out in the water for whatever reason. And at that point, a decision has to be made in terms of euthanising the whales.
I have talked to a couple of Rangers that have had to do this. And I suspect it might be the worst job in the world. Can you tell us what that's about, and how we make those decisions, and what's involved, just so the public understand? Because I think sometimes it's really hard to read that a bunch of whales turned up, but there were 1,000 people there, but then we had kill them anyway. So talk us through that so that people understand how we come to that.
Hannah: This is, again, going to depend on the species that turns up. Because some, like beaked whales and pygmy sperm whales, if they're washing up, it's probably because they're sick anyway. But for pilot whales and stuff, which we know can be re-floated, our staff are going to be monitoring their condition as the day or days go on. And when they've been re-floated several times over several days, it's quite often that their condition will be deteriorating. And that will be quite obvious.
And so if they decide that their condition means that they aren't going to be able to survive even if they are put back in the water, and if they've come back in several times, they might make the unfortunate decision to euthanise the animal. And that's just so that they don't suffer a long, drawn out death. That's a humane choice. But it's not taken lightly.
Nic: No, it's difficult for the staff involved, isn't it?
Hannah: Very emotional for the staff, very emotional for people who have been helping out on the beach.
Nic: So for the people that do turn up-- and again, it's summer. We're all roaring around, hanging out at the beach. What's the best way that people can help? Let's say that there is a pilot whale stranding. And people arrive en masse to help. What is the best thing they can do to be helpful and not a hindrance?
Hannah: Well, something you can do in advance is take a Project Jonah Marine Mammal Medic Course.
Nic: Oh, I've done one of those!
Hannah: You have? That’s great!
So they will basically teach you all you need to know about how to help in a marine mammal stranding, which includes providing first aid to the dolphins and how to actually re-float them.
Nic: [With] Wally the Whale-- ?
Hannah: I don't know if that's its name. But –
Nic: they have like –
Hannah: There are life-size whales and dolphins there to practice on.
So if you've done that, that's great. You'll be able to be a big assistance. But even if you haven't done that, if DOC's requesting volunteers-- which they'll often do through social media or on the radio-- you can come down. And even if you aren't necessarily helping directly with the whales, we always need people to help with, say, traffic control, food even.
We really need to keep all our volunteers safe and healthy. So assistance with that sort of stuff is great. And we might be making chains to the sea to get water back and forth. All the things like that are really helpful.
Nic: And what kinds of things can they bring down? Is it still the thing they used to say-- you bring sheets down...
Hannah: Yeah, we have a list of everything that you might need to bring on our website. But if you want to be in the water, helping is great if you bring a wetsuit. You need to be self-sufficient.
So your car should have plenty of petrol in it. You need to bring your own water, your food, everything like that. If you're planning to stay the night, you need to be prepared with the tent, sleeping bag, et cetera … and maybe some first aid stuff, as well.
Nic: Right. But the overarching message here is go get through Project Jonah.
Hannah: Yeah, definitely.
Nic: And do a Mammal Medic course.
Hannah: It's the best way to be prepared to help with a whale stranding. And then you'll be called out when there's one happening in your area.
Nic: The other thing I wanted to talk about-- because I've been talking a lot lately with Iwi groups who are involved with whales strandings and what it means to them. And you often hear about the whale bone, particularly jaw bones, that kind of thing. Can you tell us a bit about that process and what's happened for our work with local iwi?
Hannah: Yeah, so iwi treat these species as taonga species. And they see them as their ancestors. And they have a lot of traditional knowledge about recovering the bones and carving them into jewellery and other various things. So we work closely with iwi in each area on establishing protocols that we’ll work with them when the strandings happen.
And we consult them with every step of the stranding, as well. So whether we want to euthanise [the whales], take a sample, bury them, or see them off for a necropsy, iwi is always consulted. Because they are such important taonga species for them.
Nic: Yeah. And as you say, they're their ancestors. You wouldn't want someone making decisions about your grandfather without you having some kind of say.
So you've got a really neat job in DOC. There will be a lot of people out there that would say this would be their dream job, right?
Hannah: [LAUGHS] Yes.
Nic: What sort of journey did you go on with your education and perhaps some of your work experience that got you here? What is it that motivates you to want to help out in this particular marine mammal stranding space?
Hannah: So I studied at Victoria University of Wellington. I did an Undergrad in marine biology, and ecology, and biodiversity. And then I did a Master's in marine conservation at Victoria, as well.
And as I was finishing up that degree, I started volunteering for DOC, cleaning up some marine mammal data. I guess what motivates me is thinking about what the marine life around New Zealand used to look like, Southern right whales breeding in Wellington Harbour, and things like that. And the fact that we might be able to see that again in the future is definitely really motivating. And I hope that we get to see that, or at least future generations will get to see that.
Nic: Yeah, Southern right whales is a nice story of just slowly but surely coming back, isn't it?
Hannah: Definitely. And we had our own Southern right whale encounter in Wellington this year with so-called Matariki the Whale spending over a week now in our Harbour, which was really exciting experience for everyone on our team. And that's probably my favourite thing of the year, actually. [LAUGHS]
Because so often, we're dealing with strandings and stuff, and it's quite sad. But this was actually really sort of happy, exciting thing to be dealing with. And all the public was really excited. People were breaking the law, stopping on motorways, and going out in thunderstorms just to look at this thing, like get a glimpse of it.
So that was a great experience. And we got to work with the harbourmaster, the police, and the Council on this. We obviously had to provide advice to the Council about the fireworks, which was a brand-new experience that none of us expected to have to do.
Nic: Did they cancel them in the end?
Hannah: They postponed them to the following weekend.
Nic: Because they didn't want to upset the whale.
Hannah: We didn't know how the whale would react. And with all the extra vessels on the water, we thought it would be safer to postpone.
Nic: Bless. I love that story. That is a real story of Wellington, the wildlife capital, isn't it?
Nic: It puts off its fireworks display, because it doesn't want to disturb the whale. What is the most unusual thing that you have ever experienced washing up around the country?
Hannah: Well, I haven't personally seen it. But this year, there was this thing called a spoon worm that washed up. Did you hear about this? [LAUGHS]
Nic: Somebody sent me a picture of it. [LAUGHING] Because people think that I know what all the things are.
Hannah: What was it described as?
Nic: It was described as looking like a half-cooked sausage with teeth, or a certain male appendage.
Take caution when you're Google Imaging Search this.
Nic: So my grossest marine mammal story-- because they are gross, right? You come across a festering, dead corpse of a marine mammal. It's never Flipper. It smells. It's yuck. The eyeballs hang out. It's not fun.
Hannah: I'm lucky enough not to have smelt a decomposing dolphin yet.
Nic: In this particular instance -- which was a many years ago now, I just want to qualify-- so many years ago; but it was while we were collecting biopsy samples for stranded Hector's dolphins. And the Ranger in question-- I won't even geographically locate it. Somewhere in New Zealand -- the ranger in question who shall not be named, went to a report of a stranded Hector's dolphin. And you know, Hector's dolphins, they're only little aren't they, they're only--
Nic: Thank you! And that's why you're the expert. And so it had been there for some days. So it was sort of blown up. The description I got was it was like a big purple grape.
And so he put on the white suit. And he thought, I'm not going to let this get me. I know what's going to happen here.
So he took his knife to get the biopsy sample, because we really needed them for the database. And he leaned over the dolphin and just gave it a little nick on the other side. Because he didn't want it to burst open. Like, you know [MAKES RUPTURE SOUND]
But it was so distended and so blown up in the hot sun that, as soon as he nicked it, it just split open and exploded into his face! And he had his mouth open. And it went down his throat.
And I said--
Hannah: Is that in Risk Manager?
Nic: Yeah, well, that's right. And so, in hindsight—you know, these days, that wouldn't occur. However, I said to him, ‘what did you do?’ Like, what do you do when it dead dolphin explodes into your mouth? And he said he just waded into the sea, and chundered, and threw up until it was all gone.
That is the worst dolphin work story ever. Anyway, health and safety regulations would dictate that would never happen today. However, it's still one of the grossest stories. That and an exploding septic tank are my two favourite stories. But they both occurred about 30 years ago now.
I’ll save that for another podcast. OK, Hannah, I just really want to thank you for sharing stories about your work and, particularly, for sharing your experience and your knowledge around trying to understand strandings, which, it seems to me-- we don't yet, do we?
Hannah: Unfortunately not. Yes, we are trying to. But we're not quite there yet.
Nic: Yeah. And to help support people, whether they're DOC Rangers, or members of the public, or visitors who want to help-- and knowing kind of what to expect, and how to prepare, how to train, that's been really useful, too. But your message around giving wildlife their space is such an important one. And it is so hard for people when it comes to dolphins and whales. Sometimes I feel like penguins is a subcategory of this.
Hannah: Seals, as well.
Nic: Seals! People go bananas for some reason when they see dolphins or whales. And it almost goes against every kind of fibre of our being to not get up in their grill. But I think that's our message, isn't it?
Just keep your space. Don't be a close talker. Go over there. And watch them enjoying their life from over there, whether that's in your boat, on the beach, with a drone, in any of those.
Hannah: Correct. Yep. Give them their space. We all know we to get close to our marine species. But it's important to keep your distance to avoid stress and harm to the animals.
Nic: And I think the other thing you've done is been a wee bit of a source of inspiration for all those up-and-coming marine specialists and scientists that are out there to show them that there is, in fact, really important work to be done. And I'm sure we might expect to see people like that on our team. So it's nice to have a bit of career inspiration.
Hannah: Yeah, you're welcome. It may not always be glamorous. You might not be out counting dolphins. But it is important and interesting work that can be done behind a desk, too. [LAUGHING]
Nic: Well done. Thank you so much, Hannah.
Hannah: It’s been a pleasure.
Nic: And I look forward to hearing more about your work. Thanks.
Hannah: Thanks, Nic.