rewilding

Rewilding the Desert: First Steps

A few weeks ago, our productions team trekked west to Victoria's Little Desert - the site of an ambitious project that aims to return species that are now gone from the area. FAUNA Research Alliance, in partnership with Conservation Volunteers Australia, are rewilding the Little Desert in an attempt to rebalance the desert's ecosystem and engage the local community in conservation.

Like all good land management, an essential part of this project is establishing baseline data on the Little Desert's biodiversity.  To understand how western quolls and bettongs affect the ecosystem upon their return, FAUNA and Conservation Volunteers need to know the Little Desert's current state. What species already occur in the landscape? What food might be present for the quolls?

Wild Melbourne was lucky enough to capture some of these surveys, including pit-fall trapping - a technique used to survey reptiles, small mammals and invertebrates. See our photos below for some of the highlights. 

The Little Desert put on a show for us during our early morning trap checks. 

Trekking to the pitfall lines  Photo: Robert Geary

Trekking to the pitfall lines Photo: Robert Geary

Pitfall trapping is a technique that uses what's called a 'drift fence' that stretches for a few dozen metres, not allowing animals to pass. Buckets dug into the ground are evenly spaced along the fence, so that animals trying to get past the fence fall into the buckets instead. 

Dr Dave Watson (FAUNA Research Alliance) inspects a pitfall trap  Photo: Robert Geary

Dr Dave Watson (FAUNA Research Alliance) inspects a pitfall trap Photo: Robert Geary

The Little Desert woodland provided a picturesque backdrop for the surveys. 

Dr Dave Taggart (FAUNA Research Alliance) checks the drift fence.  Photo: Robert Geary

Dr Dave Taggart (FAUNA Research Alliance) checks the drift fence. Photo: Robert Geary

Funnel traps can be used to catch larger animals, like snakes, that don't fit into the pitfall buckets. 

Dave Taggart and Dave Watson check a funnel trap for life.  Photo: Robert Geary

Dave Taggart and Dave Watson check a funnel trap for life. Photo: Robert Geary

Our early morning starts were worth it, with the pitfall traps yielding silky mice (Pseudomys apodemoides), and a range of skink species. This is incredibly positive, as these species would provide a great source of food for quolls, once they are reintroduced to the area. 

Ben Holmes (Conservation Volunteers Australia) checks a silky mouse after removing it from a pitfall trap.  Photo: Robert Geary

Ben Holmes (Conservation Volunteers Australia) checks a silky mouse after removing it from a pitfall trap. Photo: Robert Geary

Silky mice were the most common mammal, and incredibly cute. 

A silky mouse posing for the camera.  Photo: Robert Geary

A silky mouse posing for the camera. Photo: Robert Geary

Monitoring is set to continue, with the FAUNA and Conservation Volunteers teams working hard to establish a baseline picture of how the Little Desert's plants and animals are doing. Getting an idea of the current state of the environment is important, so that any changes that occur once rewilding begins can be documented, and managed for if neccessary. 

Photo: Robert Geary

Photo: Robert Geary

For more information, read our earlier interview with Rewilding Manager Ben Holmes or head to FAUNA Research Alliance's website. 

All images by Robert Geary

Oasis in the Desert

Imagine, just for a second, that you were transported to far-Western Victoria as it was 300 years ago. The sweeping plains and occasional dunes continue on as far as the eye can see, with not a scrap of barbed wire in sight. There are enormous malleefowl mounds everywhere; on every sand dune the scurried traces of bilbies, quolls and bettongs abound. The many stemmed eucalypts explode from the sand in slow motion, hinting at a fire-scorched past.

These days, the Little Desert tells a different story: a story of rabbits, weeds and European farming. But what if that picture first painted could be recreated? What if the Little Desert, or at least sections of it, could hark back to a wilder time?

Medium-sized mammals like this rufous bettong (left) and brush-tailed bettong (right) once roamed the Little Desert.  Image: Emma Walsh

Medium-sized mammals like this rufous bettong (left) and brush-tailed bettong (right) once roamed the Little Desert. Image: Emma Walsh

Conservation Volunteers Australia, in partnership with FAUNA Research Alliance and the Little Desert Nature Lodge, are hoping to do just that using rewilding, an emerging approach to conservation. Essentially, rewilding means reintroducing species where they once were and generally allowing nature to take its course. Putting the wild back into nature, as it were. The practice has grown to prominence recently in the UK, with the proposed reintroduction of lynx in Scotland. In Australia, a rewilded Little Desert may give people the opportunity to experience a Victorian landscape as it once was.

For Ben Holmes, Rewilding Manager at Conservation Volunteers, the opportunity to help rewild the Little Desert is an exciting prospect, especially given the rapid decline of Australia’s biodiversity: “If we can prove that rewilding works and implement it at landscape scales, we might be able to conserve some of Australia’s threatened species, and that’s why I’m on board.”

As Ben explains the Little Desert project in depth, it’s difficult to stop the mind from wandering, marveling at the possibilities that come with rewilding and what it means for conservation: “It’s time to try something new, and the evidence from around the world is starting to show that rewilding might be a key piece of the conservation puzzle.” Indeed, if a conservation program as ambitious as this is successful, it could inspire many others across Australia.

The effects of rewilding aren’t just about conservation, though; they can also permeate throughout society. Ben and Conservation Volunteers also want to use the project to rewild people: “Giving volunteers and the community an opportunity to get involved in a meaningful conservation project and connect with nature and Australia’s unique wildlife is integral to our vision.” Studies from many corners of the world show the benefits of connecting humans with nature.

Conservation projects can often take a little while to get going and while this project is two years in the making so far, Ben and Conservation Volunteers are keen to get things moving quickly: “Our aim is to run our monitoring program this spring and summer to give us an understanding of what species are here and how the ecosystem is functioning.”

The Little Desert Nature Lodge's predator-proof fences will keep the rewilded species safe from invasive predators, as well as provide a controlled environment in which to conduct the management experiments.  Image: Billy Geary

The Little Desert Nature Lodge's predator-proof fences will keep the rewilded species safe from invasive predators, as well as provide a controlled environment in which to conduct the management experiments. Image: Billy Geary

After reaching this milestone – a crucial step in science – it’s time for the main event: “In about 12 months time, we will start reintroducing animals and monitoring their impact on the ecosystem.” The proposed species read like a mammal-watcher’s wishlist, with the western quoll, numbat, brush-tailed bettong and western barred bandicoot all expected to be returning home in the imminent future. All of these species are incredibly charismatic, but also in dire need of conservation support.

To reach this point, however, Conservation Volunteers and FAUNA Research Alliance are already years into the project, says Ben. Part of this is ensuring that this ambitious project is backed by the best science available: “FAUNA Research Alliance is helping us to develop a scientifically rigorous monitoring and research program to assess the impacts of rewilding. The baseline-monitoring program is being developed so that it can be undertaken by the community. For more complex monitoring and research, the academics from FAUNA will help us to find students to deliver the work.”

Very soon, species that haven't been in this landscape for 300 years will return.  Image: Billy Geary

Very soon, species that haven't been in this landscape for 300 years will return. Image: Billy Geary

Despite the continued and seemingly unstoppable rise of rewilding in scientific literature as a viable addition to a land manager’s toolkit, it does have its critics. Some suggest that rewilding has too many unknowns associated with it, or that some proposals are unrealistic in their goals. However, Ben reiterates that the team is taking an evidence-based approach: “FAUNA Research Alliance, with their wealth of scientific knowledge and management expertise has helped design the scientific program to evaluate rewilding as a conservation tool. This, in combination with Conservation Volunteers’ community engagement skill and infrastructure, means the experiment can happen with minimal risk. Together we can make this happen.”

It’s that theme of togetherness that is fundamental to the ethos of Conservation Volunteers and those associated with the Little Desert project. As Ben explains, the community and volunteers will be involved every step of the way: “We will be developing a range of volunteer opportunities for the local and wider community. No matter where you’re from, you can come and stay with us at the Little Desert Nature Lodge, get your hands dirty and help rewild the desert.”

Given the precarious state of many species in Australia, and indeed Victoria, giving them a chance at a new (but very old) home can only be a good thing. Besides, what Victorian wouldn’t want to see bilbies, western quolls and numbats darting through the Little Desert as they once did, many years ago?


Billy Geary
Billy is the Science & Conservation Editor at Wild Melbourne. He is a wildlife ecologist interested in predator-prey interactions and invasive species management.

You can find him on Twitter at: @billy_geary

No place like home: the case for rewilding the Tasmanian devil

Tassie Devils are amazing creatures, but their situation is dire. Australia’s largest marsupial carnivore is one of the few species on Earth whose major plight isn’t caused by humans. Rather, it is caused by something much more insidious – evolution.

Evolution, in combination with low genetic diversity caused by a series of historical population crashes, has conjured up a horrible illness called the Devil Facial Tumour Disease or DFTD. Originating from the mutated cell of a single devil, DFTD causes large, cancerous growths to form in the animal’s mouth, preventing feeding and often causing death due to starvation. It’s a horrible way to go.

The devastating facial tumour disease. Photo source: Menna Jones / Wikimedia Commons

The devastating facial tumour disease.
Photo source: Menna Jones / Wikimedia Commons

However, what is most frightening about this tumour is that it is contagious - among devils, not people. Devils often feed together on the same carcass, or even fight over it. This causes the cancer cells to move from devil to devil through saliva in their food as they argue over the last scraps. It’s this aggressive, transmissible quality that has seen the cancer spread like wildfire from one single individual to nearly the entire Tasmanian population, from east to west. The result is a species teetering on the brink of extinction. 

Despite a lot of work being done on creating vaccines for DFTD, maintaining captive breeding populations and, recently, establishing a wild population on Maria Island free of DFTD, this may not be enough. A new, potentially game changing proposal has also been gaining momentum: to re-establish or rewild disease-free populations of the Tassie Devil to mainland Australia. This kind of innovative thinking could be the saviour of the species. 

So, what is the case for rewilding the Tasmanian Devil?  

Is it time for the Tasmanian devil to return to its former home? Photo: SJ Bennett

Is it time for the Tasmanian devil to return to its former home? Photo: SJ Bennett

1. Devils used to be here, anyway

Fossils show that the devil coexisted with other native mammals on the mainland up until fairly recently (5000 to 400 years ago, depending on the accuracy of the dating). In fact, Devils once lived far up into the north of the country. Why did they disappear? No one knows for sure, but hunting by Indigenous Australians and the introduction of the dingo may have had something to do with it. 

Because of this, we can be fairly sure that devils, if brought back to mainland Australia, wouldn’t be another cane toad or European carp disaster, eating everything in its path. Also, Devils have lived with an enormous range of bite-sized marsupials in Tasmania, much more than mainland Australia. This suggests that Devils are capable of coexisting with smaller prey species without hunting them to extinction. 

Recent research using species distribution models has shown that the prevailing climate is just right for devils across south eastern Australia. According to this modelling, places like Wilson's Promontory and Barrington Tops might be perfect homes for Devils.

The former range of the Tasmanian devil. Source: Rewilding Australia

The former range of the Tasmanian devil.
Source: Rewilding Australia

The potential climatic range of the Tasmanian devil. Source: based on  Hunter et al. (2015)


The potential climatic range of the Tasmanian devil. Source: based on Hunter et al. (2015)

2. Devils need More insurance populations

The species needs insurance populations that are disease-free, simply so that the devil’s survival is ensured. Captive breeding programs have been the saviours of species many times over, but they can sometimes struggle to emulate the experiences of living in the wild. As the saying goes; ‘there’s no place like home.’ A wild, disease-free population will maintain the instincts and behaviours required for survival, as well as providing another source of genetic diversity for the species. These two things will be vital when the time comes to help build the Tasmanian population back up to historical levels.

Indeed, there’s evidence that Devil introductions or reintroductions can occur successfully.  A couple of years ago, a population of devils was established on Maria Island on the east coast of Tasmania. This is the first time devils have existed on the island and there’s every indication that individuals cope with moving houses, with little harm on existing native wildlife. 

Are captive populations enough to keep the devil going? Photo: Jay Town

Are captive populations enough to keep the devil going? Photo: Jay Town

3. Devils may help balance our ecosystems

Where they persist, Tasmanian devils are apex predators. They are typically quite timid and prefer carrion, but their mere presence in the environment can scare smaller species away, creating a ‘landscape of fear.’ Not dissimilar to the neighbours cat being terrified of your
otherwise lovely Jack Russell. They are capable of keeping grazing animals like rabbits down, allowing vegetation to do well. 

Perhaps more importantly, recent research has suggested that devils can also disrupt feral cat behaviour. This may mean that the devil could shield endangered prey species from predation, which has immense conservation benefit. Some recent computer modeling also supports this suggestion, even predicting that devils may scare foxes away, too.

Could the Tasmanian devil fill the same ecological role as the dingo, as explained here? Made by Daniel Hunter (Hunted Films) 

4. There's scientific and public support for a trial 

A recent public survey by Rewilding Australia found that, of over 400 respondents, 85% supported a trial reintroduction of Tasmanian devils to the mainland, whilst another 13% suggested they could be persuaded if presented with enough evidence. There's also strong scientific backing for a trial to occur in Victoria, with scientists from Deakin University, University of NSW and the University of Tasmania in support.  

Any proposed reintroduction will need to be a well thought out and planned exercise. Returning the Tasmanian devil to its original home, such as Wilson's Promontory, has real potential to not only help secure a species, but also provide greater benefits on an ecosystem scale. There will be tensions that need to be addressed, but ultimately the pros outweigh the cons to the point where reintroducing the Devil needs to be considered, such as the proposal outlined by Zoos Victoria in their Conservation Master Plan. With a dying population due to DFTD, proactive and innovative solutions are required. So, perhaps it’s time to welcome the devil back to its ancient home and recreate a thriving ecosystem. 

Cover image supplied by Catherine Cavallo


Billy Geary
Billy is the Science & Conservation Editor at Wild Melbourne. He is a wildlife ecologist interested in predator-prey interactions and invasive species management.

You can find him on Twitter: @billy_geary
 

Review: Advances In Reintroduction Biology

The Book: Advances in Reintroduction Biology

Authors: Doug Armstrong et al.

If you’re at all involved in animal reintroductions down under, then you need this book in your library. Whether you’re a researcher, manager, or both, this text offers a neat but comprehensive package of what’s been learned about reintroductions from the tumultuous conservation history of Australia and New Zealand.

Reintroduction, defined as the intentional movement and release of an organism inside its indigenous range from which it’s disappeared, has become an essential conservation tool. However, this rapidly growing practice is replete with risks and management issues that require expert planning and a sound understanding of the species and ecosystems in question. This book addresses the issues most pertinent in the current realm of wildlife reintroductions, discussing everything from disease risk and genetic diversity, to the role of zoos and the optimal strategies for release. As a result, the reader is primed with the latest wisdom of the reintroduction field within a uniquely Australian and New Zealand context.    

Special attention is given to dealing with the invasive predators and prey naivety that has become a trademark of Australian and New Zealand conservation threats. As the authors point out, mortality due to exotic predators is the leading cause of reintroduction failures. To this end, the authors provide clear instructions on the use of predator exclusion fences and lethal control, as well an overview of more novel approaches such as utilising the ‘landscape of fear’ theory to supress exotic mesopredators (medium-sized predators that simultaneously predate and are predated upon). The relatively neglected subject of prey naivety is reviewed, with the authors providing a glimpse of the exciting potential that this area offers under a currently shifting paradigm.   

The increasing importance of privately owned sanctuaries is discussed with case studies involving Bush Heritage and the Australian Wildlife Conservancy, and advances in captive breeding and the impetus of viable insurance populations are also revised with regards to the conservation role of zoos. Elsewhere, the reader is presented with a useful table to assist in identifying the needs of connectivity for organisms with different dispersal potentials.

What I find particularly impressive is the entire chapter dedicated to “forty years of fauna translocations in Western Australia”. Chronicling the lessons learned from the translocation of some 12, 000 individual animals, the authors point to a need for better monitoring and reporting techniques to ensure that the relative success of a translocation can be accurately measured, with the details of improving on these methods coherently laid out in the preceding pages. Furthermore, they impress upon the reader the importance of recognizing translocations for what they are: rare research opportunities from which valuable knowledge can be gained. Thus, the importance of capitalising on scientific opportunities shines through as a key lesson in this and other chapters.

Packed with case studies, guidelines, and future directions, this text offers not only a thorough review of reintroduction theory but acts as an up-to-date manual for the practice of faunal reintroduction. Given the current ecological crisis and increasing move towards animal reintroductions, managers and researchers stand to gain much from having such a book handy, as do our native wildlife.

This book belongs on your shelf if... you're a researcher or manager involved with reintroduction biology or hoping to learn more about it.