fire

Time Warp: 32 Years of Environmental Change in Victoria

Victoria has changed substantially over the last few decades. We've had enormous environmental perturbations, such as the 2003 Alpine fires that burnt 1.3 million hectares of land and the rolling booms and busts of rainfall associated with the El Nino cycle. We've also seen Melbourne's continued expansion as our population grows. But rarely are we able to visualise some of these changes easily, and at a scale that allows us to conceptualise just how much change has occurred.

Luckily, the release of Google's satellite photography time lapse project allows just that - we can now see how the world has changed over the past 32 years, from the perspective of space. We've picked through much of Victoria, known for its variable climate and environmental disturbances, in search of some of the most striking and eye-opening changes and environmental variations.

What we've found is pretty incredible. 

A State-wide View

Take a look at Victoria as a whole. From tall forests to farmland, and mallee to Melbourne, this time-lapse is striking in that it shows just how much Victoria has changed in the past thirty years - even in the most remote parts of the state, such as Wyperfeld and Croajingalong National Parks.  

The Growth of Melbourne

In our capital, you can see suburbs sprawling around Port Phillip Bay to the east and west, the pace quickening in more recent years as the city's population raced past four million. It's likely that these rates of growth will continue into the future as well, signalling further environmental change. 

<

Fire in the Central Highlands

On Melbourne's doorstep, we have the Central Highlands. Here, it's the striking impact of the Black Saturday fires that is most apparent. As the timeline flicks over from 2008 to 2009, the dark green of the mountain ash turns to grey, highlighting the enormous scale of these devastating fires.  

East Gippsland

In Victoria's far-east, the thirty years of environmental change in eucalypt forest is substantial. Fire and a dynamic climate are apparent here as the forest changes over the years. This particular view emphasises the kinds of scales that processes like fire operate on, and that very little of Victoria remains untouched by humans. 

Where The Snowy Meets The Sea

Google's time-lapse technology also offers a look at how some of our river systems have changed over time. Where Victoria's iconic Snowy River meets Bass Strait, the river mouth snakes up and down the coast every year with the tides, shifting enormous amounts of sand in the process. 

Lake Eildon

We can also gain new perspectives of Victoria's dynamic climate over the years by looking at how some of our lakes have changed. Here, Lake Eildon dries and fills every few years in line with rainfall. Over the course of the Big Dry (1997-2009), Eildon progressively becomes drier and drier, only to fill up again in the 2010-11 Big Wet. This particular time lapse really hits home with how much drought can affect Victoria's systems. 

Fire in the Mallee

In Victoria's mallee ecosystems, the effects of individual fires scar the landscape for over 100 years. As each year rolls through in the time lapse, new scars appear as fire incinerates the vegetation, leaving only dirt and ash. Of particular note is the enormous Big Desert fire in 2003 that covered over 180,000 Ha of land. The contrast of these with the fires in East Gippsland is dramatic - from space, the temperate forests of the east appear to regenerate within a few years, whereas in the mallee, the changes brought on by fire last for much longer

Booms and Busts of the Grampians

To the south-east, we can see how Victoria's increasingly dynamic climate is affecting the beautiful Grampians. We know how much the Grampians' small mammal populations vary with fire and climate from year to year, and by studying this series of images it's easy to understand why. The filling and drying lakes tell a story of unreliable rainfall (see Wartook Reservoir in the north and Rocklands Reservoir to the west). At the same time, fires create a complex patchwork of vegetation across the landscape. 


These time lapse videos provide a whole new way to conceptualise environmental change in Victoria, and indeed the world. The impacts of fire, climate, and human society are apparent all across the state, the scale of which, at times, is incredible. Hopefully, these will videos go some way to contextualising that change, and put into perspective just how much our world varies from year to year. Often as a result of us, too.  

To explore Google Timelapse, head to this link.

Getting to know Gariwerd

From burning to booming (and back again) - a tale of fire and water. 

Back in 2006, a major wildfire burned approximately 85,000 hectares of the Grampians National Park. Lightning sparked the blaze and a burning question – how will the system respond to this large, high intensity fire? Although we didn’t know it at the time, this event was the forerunner to the birth of a long term study and partnership. Every year for the past nine years, a Deakin Wildlife and Conservation Biology Honours student has taken on the task of delivering the Grampians mammal trapping.  Without fail, these students have (with some trepidation) dived into the experience before emerging triumphant and as confident and competent researchers. 

We annually trap 36 study sites throughout the park. When the trapping first began, we were inundated by exotic species (mostly the invasive house mouse). The region was recently burnt but was also in the grips of the ‘Millennium Drought’ – not an ideal situation. After a few more years of poor rain, the landscape was drenched for the first time in many years and with that, the drought was broken (but sadly not for long!). With the downpour came an uprising.

In 2012, 18 months after the deluge, the mammal numbers had boomed, doubling from the previous year and almost four times the numbers of the first year. The sheer amount of mammals was not the only change; the composition had shifted to a landscape dominated by native species. This was an exciting time with the smoky mouse being detected for the first time in the study, as well as an albino heath mouse and many bandicoots carrying pouch young captured.

While these conditions seemed to be conducive to small mammals, it presented a number of challenges for our research team. Many roads crumbled during the onslaught of rain, making access incredibly difficult and time consuming. After many kilometres at a snail’s pace, help from the Parks Victoria quad bike, and a series of turnarounds, trapping was completed. 

Following on from this boom the rainfall once again began to decline. As a result, the mammal numbers followed suit before stabilising at low numbers from 2014 onwards. Native species are still managing to dominate the landscape, although in the last two years the number of house mice has begun to increase – funnily enough there were 127 captures in both 2015 and 2016, what are the chances!? As these conditions have unfolded, we have seen an incredible opportunity to investigate the impacts of future climate change. Future scenarios outline an era where there is a highly variable climate, with protracted periods of below average rainfall punctuated by flooding events. It was like looking in a mirror! 

Since we began our investigation into the effects of variable climate, our research has yielded some unexpected results. What we have found indicates that our temperate system is acting much like the arid regions of Australia. In arid zones, mammals experience booms and busts associated with the sporadic rainfall that these areas receive. What we’ve found is that our system (originally thought to be more predictable and stable in that sense) was responding this way as well. 

With native species showing a preference for areas that remain unburnt for longer, the pattern of wildfire occurrence becomes increasingly worrying; with larger and more regular fires looking to become the norm, the future of our native species may be threatened.  In the last 10 years alone, approximately 90% of the Grampians National Park has experienced wildfire (in 2006, 2013 and 2014!), leaving very few long unburnt areas. This means that the distribution of fire age classes is less than optimal for small mammals.

The interaction between the effects of fire and climate create a complex web to manage for biodiversity; it does, however, provide hope. We have seen populations bounce back from almost undetectable levels, so as long as conditions don’t remain sub-optimal for extended periods and large, high intensity wildfires do not increase in number, experienced species should have the capacity to recover.

Our experience in the Grampians has been amazing, and thought-provoking. We have realised the significance of and invaluable knowledge obtained from long term studies, especially when facing the uncertainty of the effects of future climate change. It allows us to observe the peaks and troughs experienced by a system that may have been overlooked or undetectable in a snap shot study. While snap shot studies are important, we need to value and support long term studies, particularly as the onset of climate change intensifies.

Check out our latest paper from our Grampians research here.  

Follow our research on Twitter @Wild_Gramps


This is a guest post by Deakin University PhD student Susannah Hale and Associate Professor John White.

All images taken by Susannah Hale

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

Science Shorts: Fire, Climate, and Small Mammals

This month, we were fortunate enough to visit the beautiful Grampians National Park and chat with Deakin researcher, John White. John has worked on the ecology of the Grampians for around a decade, and his team's research has yielded surprising insights into the influence of climate on small mammal populations. 

Oddly similar to the boom and bust ecology found in arid ecosystems, the small mammals of our Grampians appear to be highly responsive to rainfall. During dry periods populations are low but they soon explode following high rainfall events. While this is interesting from a scientific perspective, it raises questions about the longevity of our small mammal populations in the Grampians. As our climate shifts and dry periods become more frequent and more enduring, the isolated populations 3-4 hours West of Melbourne may struggle to hang on. 


Adding to their struggle is the increasing risk of large, intense fires. Such disturbance events may outright kill our furry friends, or deprive them of the food or cover necessary for them to survive at high numbers. However, as John's PhD student Sussie is finding, there are some areas within the Grampians' vast expanses that tend to be less prone to burning and retain moisture during dryer periods. These wetter refuges offer our small mammals a heightened chance at survival  and may be the key to conserving these species in this ruggedly beautiful but precarious landscape. 

 

Wild Melbourne's Chris McCormack speaks with John White and his PhD student, Susannah Hale of Deakin University about their ecological research in the Grampians National Park. John's team are finding fascinating responses of small mammals to fire and climate in this amazing Victorian landscape.

Photos credit Robert Geary