From the field: Studying endangered northern quolls on Groote Eylandt

It's a new year, which means there's new research to be done as I delve into my PhD. But before I start writing about that, I want to write about a somewhat related experience I was lucky enough to have last year.

In August/September, I got to join my labmates Ami, Jaime, and Gwen up on Groote Eylandt, which is a large island off the coast of the Northern Territory owned and run by the Anindilyakwa people. The reason: to help them out with their research on the endangered Northern Quoll (Dasyurus hallucatus).

Catwoman, a pretty little female Northern Quoll ( Dasyurus hallucatus ). 

Catwoman, a pretty little female Northern Quoll (Dasyurus hallucatus). 

A classy addition to any accessory collection. Image credit: Wikimedia Commons. 

A classy addition to any accessory collection. Image credit: Wikimedia Commons. 

Now, if you’ve ever been to Australia, you probably have heard the story of the Cane Toad (Rhinella marina) – even if it’s just via one of the many delightful novelty souvenirs available in Australian tourist shops.

The cane toad is an extremely successful invasive species that was introduced into Australia in 1935 to eat a beetle that was negatively affecting the cane industry (which it didn’t), and since then it has spread down the East coast and across the Northern Territory, and is slowly making its way down the West coast as well. One of the reasons Groote Eylandt is so amazing is because it is one of the few areas up North that has remained cane toad-free. Because of this exclusion, it is the last stronghold population of the endangered Northern Quoll, whose numbers have been decimated via their predation on this toxic species. This makes Groote an ideal location to study the quoll in its natural habitat, as numbers are high enough for recapture studies to generate useful amounts of data.

A magical sunset in the bush next to the highway to Umbakumba.                                              Ami measuring one of our little darlings. 

I was on Groote Eylandt for 5 weeks helping Ami with data collection for her PhD project. As well as stunning landscapes and amazing native animals, Groote Eylandt is also home to a large manganese mine. All animals need some amount of manganese to function, but like any heavy metal it can be toxic in high concentrations. For her PhD, Ami is looking at how quolls from different parts of the island (that have been exposed to different amounts of manganese) perform in motor control and cognitive function tests. We are lucky enough to have access to laboratory facilities at the Anindilyakwa Land and Sea Ranger Station, where we get to work with the Rangers to figure out how to do our research in a way that is compatible with indigenous culture.

We went out every night and set 30-60 traps in one of our three trapping areas various distances from the manganese mine, which we then checked first thing the next morning. If we were lucky, we’d see white spots and hear some angry growling – otherwise it was rather likely that we’d caught one of the other marsupials that populate the area. We then transported our precious bundles back to the lab at the Anindilyakwa Ranger Station where we sexed them, weighed them, took various morphological measures and a hair sample (to get their internal manganese concentration from) and pit- and ear-tagged them.

Alfred, a feisty (and adorable) little male. 

Lastly, we’d gather information on their level of motor control. I won’t give away too many details, but we basically assessed their performance at various speeds and analysed how many mistakes they made depending on the difficulty of the task and the speed at which they performed it. We would expect that as speed and/or “difficulty” of the task increases, the quolls will make more mistakes. The reasons for this are very intuitive and you will probably have observed them in your own life; as you do things faster you have less control over your movements and are more likely to make an error. Similarly, if a task is difficult, you’re more likely to make a mistake than if it’s relatively easy. What Ami wants to know is whether the manganese concentration the quoll has been exposed to enhances this effect – i.e., whether high manganese concentrations affect motor control.

Back to the bush you go.                                                                                                                              Having a sniff out of the corner of his bag. 

Ami also wants to look at whether manganese concentration affects cognitive function in the quolls – but that’s for her to write about! She’ll continue to run these experiments for the next two years, and hopefully get some excellent results. I was very lucky to be involved in helping out with this project, as many of the techniques she used will be helpful in my own PhD.

Although quolls were the main attraction for us, Groote Eylandt has plenty of other amazing qualities that made my trip there one of the most memorable ventures into the field that I’ve ever had. We are extremely privileged to be able to conduct research there, and I learned more about indigenous culture than I ever thought I would. I also saw loads of awesome animals and plants, and got to spend a lot of time in the field – which is definitely one of the best ways to spend it.

A Mertens' Water Monitor (Varanus mertensi) chilling by Milyerrngmurramaja (the "Naked Pools"). These guys are also threatened by ingestion of the cane toads. A Striated Pardalote (Pardalotus striatus) that was nesting next to the Anindilyakwa Ranger Station.

A Burton's Legless Lizard (Lialis burtonis) we found while we were setting traps near Alyangula. A Helmeted Friarbird (Philemon buceroides) next to the highway to Umbakumba.

I’d like to say a huge thank-you to my lab for this opportunity, but most especially to Ami, Jaime and Gwen for teaching me so many new skills and being the best bush-buddies ever. I’m looking forward to future adventures with the Wilson Performance Lab as I start my PhD on another kind of carnivorous marsupial… the Yellow-footed Antechinus (Antechinus flavipes)!

Sunset on the beach at Ayangkwa ("Tasman Point"). 

All images by Rebecca Wheatley unless otherwise credited.

UQ CIEF Grant awarded to the Performance Lab

- by Robbie Wilson

Last week I travelled back to Groote Eylandt to sign off on a collaborative research project with the Anindilyakwa Land Council worth $375,000 over the next two years. This supports an important project and recognizes our strengthening relationship with the people of Groote Eylandt with whom we've been working for the last five years. 

Indigenous dugong painting on Groote Eylandt

Indigenous dugong painting on Groote Eylandt

For our UQ-CIEF grant we'll be exploring the possible toxic effects of manganese from the local mining operations on the wildlife of Groote Eylandt. Groote hosts one of the world’s largest Mn mines - and despite considerable financials rewards for the local community, many locals are becoming increasingly concerned about the long-term impacts of Mn contamination for their environment. The toxic effects of Mn usually manifest in animals by affecting their cognitive and motor function, which places our research group in a unique position to tackle this research.

We'll examine the pattern of Mn accumulation in the local wildlife and then test whether any increased Mn affects motor function in our primary study animal, the northern quoll. This species offers a perfect model system because it is highly abundant across the island – both close and far from the mining operations – and we can easily adapt tests of motor control from protocols used in biomedical studies of rats and mice.

Groote Eylandt field work

Ami (PhD student) and Skye (Researcher) will be the main team members working on this project but, as always, everyone in the lab will contribute to the smooth running of the work. There is never a shortage of volunteers offering help!! We’re all excited about continuing our work with the Indigenous Rangers of Groote Eylandt and we hope they get as much out of our collaboration as we all do. My feeling is that you haven’t graduated as an Australian ecologist (or zoologist) until you’ve wandered through the bush with a real local and seen the land through their eyes. 

Thanks again to the Anindilyakwan people for their on-going trust and acceptance of our research team. We look forward to the season ahead.

Robbie 

I spent a late afternoon wandering rocky landscapes and avoiding crocodiles

Fieldwork, Groote Eylandt, NT

Leaving Darwin, the propellers outside hummed loudly (reassuringly). We pressed our noses to the windows, looked out on the wild top coast of Australia. The fires lit by thousands of years of tradition. And then, we were there. Over the mines, into the red dirt.

the GEMCO manganese mine

the GEMCO manganese mine

On the deck with Jennifer and her niece; with Chopper; with MacBook Pro

We drove east to Umbakumba then headed into the bush on sandy tracks. We set up tents on top of a berm, feeling {relatively} safe from water-borne crocs and collected firewood from the beach. We watched a heavy moon pull itself up into the sky.

Picnic Beach, Groote Eylandt | Jaime and Eddie set out, bait, and mark quoll traps

Under Jaime's guidance, we set out traps for quolls, hoping to catch at least a few to obtain measurements and hair samples.

We caught 4. Plus a few bandicoots. It was good enough for Jaime to get her samples, and good enough for me - these were the first wild quolls I'd seen.

 

It was only a week ago we got back from Groote Eylandt. What a special place. Wild, and raw, and special. An island of contrasts, between a traditional culture and a modern mining industry. An island with a lot of crocodiles.

It was my first trip up, and Nelle came along. We met the Rangers and friends and family and Gavin and Kerry and the rest of the team and Alex-from-Stanford. We drank tea on the deck at the Ranger station, and packed up everything {but petrol} for a quoll-catching venture to the east side of the island. {Former labmate} Billy was appointed Ranger Coordinator. We learned our first Anindilyakwan words. We entertained Nelle, and learned the value of ABC for Kids downloads {and PhD students}.

A quoll curled up in its very own, custom-made pillowcase | fishing for dinner

We were almost as successful catching fish ... the ocean here teems with them {apparently} but we didn't have much luck. Three fish only made it into our bellies.

That's ok. We had plenty of patience ... and potatoes. 

- written byAmanda Niehaus

Death After Sex in the Australian Bush

Charleston wasn't just about pizza and beer, though with any scientific conference that's always a part of it ...

First up, we'll hear about Jaime's poster. Jaime did a 1st class honours degree in the lab, studying the way Rhinella marinus (cane toad) tadpoles respond to the presence of predators in their environment. But that's not what she was presenting here ... Jaime also recently was accepted into the PhD program at UQ to study quolls on Groote Eylandt, and she was keen to get the word out there about her new study system.


Now.

More about quolls and sex and the bush, as conveyed by Jaime and her co-authors on the poster, Robbie and Billy {with clarifications from me along the way}

image by Candice Bywater

Death after Sex in the Australian Bush: determinants of survival and reproduction in males of the world’s largest semelparous* mammal {*meaning they die after breeding!}

The northern quoll (Dasyurus hallucatus) is a medium-sized (approx. 1 kg) predatory marsupial previously common across the entire top-end of Australia. This species is the largest known semelparous mammal in the world, which means mating is highly synchronous, males live for only one year, and males undergo total die-offs soon after the mating season.


Such population-wide male die-offs are presumably due to the physiological stress of procuring copulations and the intense fighting among males. A small proportion of females will survive to produce a second litter, but there are no documented cases of survival to a third breeding season. The young are born after a short gestation period and then carried in a rudimentary pouch for approximately 60-70 days.


Females will then leave young in dens while they forage, returning to suckle until young are independent at 4 – 5 months. Both sexes are solitary throughout the year with a home range averaging 35 ha for females and approximately 100 ha for males during the breeding season but varies greatly between individuals.


During {Jaime's} study, {she} will be investigating the morphological and performance determinants of both survival to reproductive-age and fecundity among males of this species on Groote Eylandt, an Indigenous-managed island off the coast of the Northern Territory. Northern quolls are still highly abundant on this island and this population offers a unique opportunity to understand the evolution of this extreme mating system and the role physical performance plays in the reproductive success of males.

We can't wait to hear more!

Biodiversity Research with Anindilyakwa Rangers

Our team has headed back up to Groote Eylandt (and I'm still here ... sigh ... ), so I thought I might take this opportunity to talk more about our collaboration with the Anindilyakwa people of the island. We have much to learn from each other - but more than that, collaboration between scientists and Indigenous peoples can be a rewarding and effective means of conserving the environment.


Aboriginal Australians have a powerful cultural connection to their environment. It sustains them, physically and spiritually. Conservation of biodiversity is innate, and information about the environment - the organisms that inhabit it, the seasonality of events - have been passed down via narratives and stories for thousands of years. Though this knowledge is more qualitative than quantitative, it represents a long-term picture of the environment that few, if any, scientific studies would provide.



Besides, the ability of Aboriginal trackers and rangers to navigate the bush is incomparable - which facilitates conservation-based studies of wildlife, including the northern quoll. On our trips to Groote Eylandt, our team trains the Indigenous Rangers in scientific methods of capturing, tagging, and 'processing' animals. We talk through research ideas, hypotheses, protocols, and analyses with them. And we absorb their beautiful culture.


We'll be sharing more about our current trip shortly, including photos of some very non-quoll-related fish, and a story about why Billy is currently sitting poolside at the resort, rather than working. (Ahem)

How to Catch and Process a Quoll*

*and no ... we're not making sausages out of them ...


So how do you catch a feisty little marsupial, that's nocturnal and ground-dwelling and generally doesn't like to be caught?
Ecologists typically use baited traps, but of a sort that aren't likely to harm the captured animal - like this Elliott Trap, which has a door that springs shut when the animal steps inside.

Just before dark, our intrepid quoll-catchers set out the traps (with goodies inside) and then return to camp to give the quolls a chance to find - and take - the bait.


When a quoll's been captured, we take it back to the lab to 'process' it. Which sounds really suss but actually just means that we measure them and add tracking and identification devices to them. This is so we can obtain information about the health and size of the quolls, and keep track of particular individuals over time.




After we've taken all the important measurements, it's time to 'mark' the animals. In this study, we mark with ear tags, pit tags (like microchips), and collars - which may seem like overkill, but actually allows us to collect different kinds of data.


Ear tags are like earrings that have a specific number on them, unique to the animal. This means that if we catch this quoll again, we can easily and quickly determine its identity. Ear tags, toe tags, and leg or flipper bands (depending on the animal of focus) are commonly-used by ecologists for this purpose.


Pit tags are the second line of identification ... they're inserted under the skin, and hold all the relevant information about the animal - just like the microchip that you can get for your dog or cat. The coolest thing about pit tags? You read them with a scanner.

(as in, "clean up on aisle 3 ... ")


And collars - they're for the purpose of tracking the animal, using either radio frequencies or GPS (depending on the type of collar). By tracking individuals, ecologists can learn more about how the animals interact with each other, how large their range is, and how much they move around. If you want to know more, we talked about tracking koalas here and here.

After all this, the quoll is released back into the wild ... where it is no longer the anonymous little carnivore it once was.


So now you know how to catch and process a quoll. (Or, for that matter, any animal of ecological interest). Please use your wisdom for good, not evil.

Thanks Gavin, Sean, Robbie, Billy and Bill for the great photos!