Primary Matters podcast

Kia ora koutou and welcome to Primary Matters an MPI podcast that delves into the things that matter to our primary industries. I'm Carol Stiles, and in this podcast I'll be taking a look at what's going on to keep our food and fibre industries thriving and safe. In this series, I'll be catching up with people who have crucial and often surprising jobs to protect animals, crops, our environment and the economy.

It's kind of a case of ‘you do what?’

TD: Hi, I'm Tim Day and my job involves crawling around on my hands and knees looking for poo.

CS: (Laughs) What sort of poo?

TD: Well, all sorts of poo, but wallaby poo. So my job involves searching out wallaby, and that involves getting down on your hands and knees, picking up little bits of poo and going, is this a possum poo or a wallaby poo? Is it a possum print or is it a wallaby print? We're in the game of finding tiny little populations of wallaby that are in the wrong place at the wrong time that we need to control.

CS: Tim's based in Rotorua and contracts to regional councils to try to manage wallabies. It's around the lakes that Dama wallabies have made their home. Another species, the larger Bennetts wallaby lives in the South Canterbury/North Otago regions. Wallabies were introduced to New Zealand more than a hundred years ago and it's now estimated there at least a million of them in the wild in New Zealand, quietly eating everything they can reach in forests and tucking into pastures on farms.

But getting back to their droppings.

TD: A wallaby poo looks a bit like a goat or deer poo. It's a round little sphere maybe ten millimetres round. Looks about the size of a pea, but it's got a funny little pointy end on it, just a tiny little tip on it, and there'll be a few of them scattered on the ground. They're not big clumpy poos like a sheep poo or something like that.

So you're searching for these little pellets. You have to get right down there and close to them to figure it out.

CS: And do you come home absolutely covered with prickles?

TD: Yes, one of the problems with wallaby poo it’s where wallaby live, and wallaby live in horrible tight places so my kids favourite after-work game is to sit down and see whether Dad's been in the gorse or the blackberry today and spend the rest of the day a bit like monkeys, you know, picking, picking things off your back.

Well, my kids will be looking at the backs of my hands and my shins and my legs and seeing if they can pick out blackberry thorns and bits of gorse and all that kind of thing that invariably go with searching for a wallaby poo.

CS: There are parts of the Bay of Plenty Tim doesn't need to look for wallabies. He knows they are already there in large numbers. It's the wallabies that have leaked out of those areas and look to be sitting up elsewhere that most interest him.

TD: So what we actually do is work from the outside in, so we're basically starting on the outside with our cameras, figuring out how far the wallaby have actually spread and then slowly shutting those populations down from the outside in so that will eventually shrink the area they live in right down to that central core. And then you'll get to the point where you've got a contained population, contained both by the control you're doing, but also contained by a geographical features like rivers and lakes and that sort of thing, which they are not good swimmers, they can't cross, and then you've got a chance of managing them.

I think wallaby are far less understood by even the professionals compared to, say, a possum. Everyone knows possums, as cute as they might look, cause a whole lot of damage to our forests and our birds and our wildlife and they kind of accept that possum controls are a necessary evil in order to protect our taonga species and our identity as who we are as Kiwis.

Wallaby actually are very, very similar in terms of the insidious nature they have. They're just much more secretive, they're much shyer. They also look kind of cute and furry, but in reality they are just as damaging as a possum is, we just don't understand them as well.

They basically mow everything off the forest floor.

So every little seedling that tries to pop up two little leaves will get mown flat. So if you go into a piece of forest with a wallaby in it, it's like an earth carpet. There's no understorey. They’re worse than goats, they just chew everything out and you're left with a forest that can't regrow. So it’s the middle of summer now we're getting these ex-tropical cyclones coming down, every time one does, some trees fall over. If there's no seedlings to replace those trees that fall over, what ends up in there? Invasive weeds, blackberry, gorse, you know, all that sort of thing. So yeah, our natural spaces get quite heavily modified quite quickly.

CS: Are farmers complaining about wallabies getting into their paddocks and eating the grass?

TD: Oh, absolutely. If you if you live within the core wallaby area, either in Canterbury with the Bennetts Wallaby or in and with the smaller Dama wallaby in the Bay of Plenty, if you've got a wallaby population on your farm, they are eating a tonne of dry matter. Wallaby are hardly seen because they're secretive but they’re 24-7, out there, making a mess.

CS: There's still some people I think, who don't know we have wallabies in New Zealand. Do you do you still get that reaction?

TD: Yeah, absolutely. So wallabies are Australian, right? Yeah. People just go ‘what – you’ve got wallabies?’ That’s very common and even amongst Rotorua residents you know, people who live amongst the wallaby. They wouldn't even know that they are there necessarily. If you’re not a person who goes out and uses the forests at night or regularly drives the roads at night, the chances are you've never seen a wallaby.

CS: Have you any idea how many wallabies there might be in the Bay of Plenty?

TD: I have no idea but I know, from being someone who recreationally runs at night on trails and things like that, if you ran a kilometre trail, you can see 100 wallaby. You go into the redwoods and there would be thousands of wallaby within the redwood forest. And we know that they live in family groups. A typical family group of wallaby might be 9 to 12 wallaby, but there'll be a family here and right next door, just like an urban situation, there will be another family living next to them and another one living next to them.

And their social dynamics are just like humans. You know, the teenagers will be leaving home and knocking on the neighbour's door because they quite like the look of the teenage girl who's next door. And yeah, so they’re just like people right…they will live as densely as the environment around them will allow and what that actually means, like many pests, they'll use that environment to the point that they destroy it.

CS: So in 2020 the government earmarked more than $27 million for wallaby control to be spread over five years, with more later to deal with the wallabies in the containment zones. The goal for the Tipu Mātoro national programme is for Aotearoa to be wallaby-free.

TD: The reality is no one really had a focus on wallaby for a long time. They were secretive. No one really understood what was going on and there were more pressing problems. Possums were perceived to be a bigger problem. We know ship rats destroy, native bird eggs and things like that in forest. So from a conservation sense wallaby probably have flown under the radar compared to other pests for a long time, you know, the way we managed wallaby was very reactive.

Someone would hit a wallaby on a road somewhere and go ‘oh that wallaby’s in the wrong place’ and so there'd be a phone call made, you know, the regional council would go, ‘we'd better send someone out to have a look’. So we'd go and have a look and plan a bit of control, but it was very piecemeal and very reactive with a tiny, tiny little budget and one of the benefits of, you know, Covid and Jobs for Nature funding and, some of the injection of money that's gone into conservation, has been things like wallaby, that were disastrously doing their thing with no human resource to try and manage that, now have some significant funding. Suddenly, for example, the work we do with game cameras, we've gone from 30 game cameras three or four years ago, to 400 now, so we can suddenly see what's going on, you know, and that means we've got the opportunity to do some control, which gives you hope.

CS: Some of the funding is also being channelled into research to better understand wallabies and to improve control techniques so they're wallaby specific. At the moment night shooting is used in open areas, but otherwise possum control methods have been tweaked for wallabies.

A wallaby-proof fence is also being built to keep wallabies inside the containment zone. The 12.5-kilometre fence runs alongside Rotorua's Whakarewarewa forest.

TD: Which will stop the wallaby from crossing the road and disappearing off yonder where they become how much harder to detect then deal to.

CS: So it has to be a certain height because they could hop over it and can they get under things?

TD: Yeah. So the wallaby fence is pretty simple, really. Just, you know, the likes of sheep netting. It has a mesh skirt that's pinned to the ground because they will, stoop down and push and gaps under the fence. And it's only the height of a sheep fence, you know, 1.1 metres above the ground. They don't actually hop a long way and they hop very fast when you see them, like a kangaroo running across the landscape, but they don't actually bounce, you know, very, very high. So they might get half a meter off the ground. They don't spring vertically, you know.

CS: Now, this fence, can the wallabies get around it at each end.

TD: Yeah. Well a fence is usually imperfect because you've got roads and people's driveways and all those kinds of things. So what you're doing with the fence is you're corralling the animals and shaping where they travel so that gives you the option to use whatever control techniques you want. You know, whether it’s night shooting with thermal scopes or whether it's trapping or poisoning, whatever you need to do, you concentrate the activity of the animal to a certain place because that's the only place they can get through.

So it gives you a lot better chance than if you have a kilometres and kilometres of open terrain that they can just pass through whenever they want.

CS: Now, you were telling me before that in order to control the wallabies, you have to control the possums first.

TD: Yeah. So we've got a project just out here which is about 800 hectares of forest. There were some wallaby detected and they’re outside that kind of containment zone. From a wallaby control perspective, they are in the death zone - in a place where it's unacceptable for us to have wallaby because if they continue to live there, there'll be no geographical barriers from this place to stop them from getting all the way to Tauranga.

So with this population, 800 hectares, we identified where the wallaby were, and they were living in about 400 hectares. And so we've implemented a bait station control operation using possum and wallaby and rodent baits and we took out between 10,000 and 12,000 possums before we even killed a wallaby. And the reason for that is that possums are dominant to wallaby.

Wallaby, as I said, they're shy and they're secretive and they kind of hide away and if you put bait out in a bait station, old mate possum is going to turn up and literally beat up every wallaby that turns up to try and take the bait. The number of possums can be incredible. So in this case, we've killed 15 possums per hectare. So in every 100 by 100 metre square, we've killed 15 possums and there's probably one or two left.

CS: You’re also working with iwi?

TD: Yeah. So we work on a whole range of conservation projects, we work with a lot of community conservation groups and hapu and iwi groups who are working on their own conservation initiatives. And of course, wallaby overlap and, in the Bay of Plenty, wallaby become a significant part of some of those control operations in some of those locations. And the success of the wallaby programme is entirely dependent on the understanding, goodwill and involvement of the landowners.

SFX - Walking in bush, leaves rustling underfoot

CS: You’re just going to mount a camera?

TD: Yes, a camera, so the camera is going to get screwed into this bracket on a tree just about half a meter off the ground, just above wallaby height.

CS: How big are these Dama wallabies?

TD: So a big male, if you looked at it, if it was sitting on its back legs, the top of its head would be about half a metre off the ground, so twice the size of a possum. But a young juvenile is about the same size as a possum, you know, so they look fairly similar.

They hop differently. But, you know, it actually is reasonably easy to mistake a possum for a wallaby. You know, possums have a big bushy tail wallaby, have a long, thin grey tail, and obviously a big, big back legs like a kangaroo, and very short stumpy front legs. They look like a bit like a tyrannosaurus rex at the front end with their little stumpy, front legs.

CS: And how often do they breed.

TD: So wallaby will breed every year. And they have usually just one juvenile and obviously they have a pouch, so they're a marsupial. And so that that juvenile will be ridiculously big by the time mum finally forces it to stop getting in and out of that pouch. It’ll be trying to clamber when it looks like it's a blimmen teenager, you know, they're like teenagers who won’t leave home - same sort of thing.

Pretty much there's no predators. I mean, there would be the odd dog, I guess, you know, that is roaming at night or something that would kill them or hunting dogs or things like that. But really, what's going to eat them? We've got no predators.

CS: The surveillance cameras are the size of a couple of packs of cards and are camouflaged.

TD: And they have a little thermal sensor on it. That means any animal that passes through it basically leaves a heat trail across the screen and that's what triggers the camera to fire. So birds and moths and mammals and those things will all trigger these cameras. So it's not uncommon for us to go back to a camera after eight weeks and have 40,000 photos.

CS: Do you get some quite sharp images?

TD: We get stunning images. You know, most wallaby images are at night because they're nocturnal, except when you happen to have put a camera somewhere where they are bedding down, during the day because they obviously hide away and sleep during the day. And every now and then we hit the jackpot and we have a camera right where they happen to be sleeping and bedding. And they’re just like humans, they get up in the middle of the night to go for a pee, all of that stuff. They get woken up in the night or they have a stretch or whatever. And so we get these cool daytime images, but mostly they’re infrared, you know, so they look black and white.

From the wallaby programme perspective, we're only interested in the wallaby, but from a personal perspective, man I’ve got some cool shots of all sorts of wildlife, you know, a falcon feeding off a possum carcass on the ground. Yeah stuff that you just would never get to see with your own eyes but because these cameras are out there all day, every day, you feel like you’re David Attenborough. You get this kind of glimpse into the life and times of these animals.

And I mean, I did a Ph.D. in animal behaviour, so the way animals live fascinates me. The cool thing about working on something like the wallaby programme is we've got all this camera gear and we actually get to learn a whole lot.

So I've got a guy that works for me Rich, He was working in the forestry industry and loved his job, but he's always been into conservation. And a few months ago, he’d been working for me for just over a year, he said to me, ‘When are we starting work?’ because that's what it feels like every day. You just feel like you’re doing something really cool. It doesn't feel like a job. It feels like we're extremely fortunate to do what we do.

CS: Tim Day from a Rotorua. MPI wants people to report sightings or signs of wallabies anywhere in New Zealand. You can do it online, just type in reportwallabies.nz.

I'm Carol Stiles and you've been listening to “You do what?” a series in MPI’s Primary Matters podcast. Thanks for listening.