What the heck is a Caltha Herbland?

By Alex Blackburn-Smith, currently doing her honours with the Research Centre for Applied Alpine Ecology at La Trobe University

The Caltha introloba Herbland Community is one of the rarest and most specialised vegetation alliances in alpine Australia, yet we know very little about it. Indeed, for 40 years, no-one has been quite sure how to classify them. Are they associated with Sphgnum bogs? Snowpatches? Are they wetlands? The rarity of Caltha Herblands has been recognised enough to list them as a threatened communities under the Flora and Fauna Guarantee Act (1998), and they have further protection under the Environment Protection and Biodiversity Conservation Act (1999) through their association with Sphagnum Bogs (listed as endangered under EPBC) and Snowpatches (critically endangered under EPBC). Yet, while Caltha Herblands are a form of wetland, and while they do commonly occur in areas of late snow lie, and while they are typically surrounded by sphagnum or bog vegetation, Caltha Herblands are a separate vegetation unit. A base study of where they are and what’s in them is critical for their management.

herbland in cloud

Caltha Herbland in low cloud on Mt Nelse

So, what are they?

Caltha Herblands are semi-aquatic, sparsely vegetated, short alpine herb fields that occur on a rocky/gravelly substratum called a ‘pavement’. They rely on a constant water source, either a ground water source, such as a spring or ground seepage, or a water course such as a creek.

 

caltha in snowmelth

Alpine Marsh-marigold, Psychrophilia introloba (formerly Caltha introloba), in flower during snowmelt

Where are they?

Whilst restricted to the Bogong High Plains in Victoria, Caltha Herblands are found in a range of different landscape setting – from steep slopes under snowpatch vegetation, to relatively flat slopes beside creeks. At least 98 patches of Caltha Herbland community have been identified across the Bogong High Plains, from the northern to southern end, both above and below the tree line.

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Caltha Herbland next to White Rocks Creek

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Caltha Herbland surrounded by Sphagnum near Mt Cope

What’s in them?

Some of the rarest alpine herbs and forbs in Australia! Key species include Psychrophila introloba (formally Caltha introloba – the species from which the community gets its name), Oreobolus pumilio, Drosera arcturi, Juncus antarticus and Celmisia sericophylla are the most common of the rare species across Caltha Herblands. Some sites contain species such as Oreomyrrhis pulvinifica, Plantago glacialis and Parantennaria uniceps which are all endangered species in Victoria and restricted to Caltha Herblands.

species in caltha herblands

Why so important?

Not only do these communities contain a whole host of listed and vulnerable species, the total area that this community takes up within Victoria is thought to be less than 2 hectares. Further, we believe that the substrata on which this community lies is a periglacial relic or fossil periglacial feature. The origin of these pavements is hypothesised to be from freeze/thaw erosion and weathering action during a past cold climate period. If this hypothesis proves correct (further study is needed to attempt to determine this), then these communities have heritage significance as well as geological and geomorphological value.

rare plants

Cushion of (A) Juncus antarticus, (B) Plantago glacialis and (C) Oreomyrrhis pulvinifica growing on a pavement.

This study

I’m currently undertaking an Honours Research project that has three aims:

  • To describe where Caltha Herblands are found within the boarder alpine landscape;
  • To determine the species composition and distribution within, and between, Caltha Herbland sites, and;
  • To determine whether they are static or dynamic systems.

Currently, this study has finished the field work phase. Abiotic, including slope, aspect, size, degree of rockiness, soil depth and water cover, and floristic data has been collected from 19 sites across the Bogong High Plains. Eight of these sites have long-term data which will enable us to look at any broad vegetation change that has occurred over the past 40 years.

collecting data

(Left) A typical floristic quadrat, (Right) Re-surveying in a long-term data site

mt nelse snow patch

Re-post from the Mountain Journal: Fires and snow gums. To keep these forests we need less fire.

We are sharing this post on about fire impacts on the high country treeline from the Mountain Journal. The original post can be found here.


 

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Fires are still burning out of control across much of the Australian High Country. Yet we are already well into the blame game, where some people and groups are blaming environmental activists and/ or The Greens party for ‘stopping’ fuel reduction burning and hence making the fires worse. While this is not true, this resonates with certain anti green and conservative demographics (check here for an alternative view of the conversation).

There is no doubt that fuel reduction burning has a role to play in how we manage forests and other landscapes. The problem is that it is often seen as a ‘one size fits all’ tool that will reduce fire intensity in all environments. But in reality, it works well in some ecosystems and is counter productive in others. This is a subtlety that is lost on the ‘fuel reduction is the answer’ boosters.

The argument that we need to increase fuel reduction burns in snow gum and true alpine environments is already caught up in the broader land management debate, and will continue in the coming months. So it’s worth taking a good look at what science says about the value of fuel reduction in our high mountain areas.

Snow gums are the quintessential alpine tree of the mainland, generally growing at elevations between 1,300 and 1,800 metres asl. Wildfire has devastated large swathes of snow gum habitat in the last few decades, with significant fires in the Victorian High Country in 1998, 2002/3, 2006/7 and 2013. Over 90% of the Victorian distribution of snow gums has been burned at least once since 2003. Each of the large fires of the last 15 years has overlapped to some extent, leaving thousands of hectares of snow gums burned by wildfire twice, and sometimes three times.

Much of Kosciuszko National Park was burnt in 2003.

‘Fire has always followed fire’

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Fire at Precipice Plain, VIC Alps, Jan 2020

 

 

Early European occupation of the mountains was based on the widespread use of fire to clear land. This broad acre approach to burning was at odds with First Nations careful, localised use of fire. As noted by Philip Zylstra (Centre for Sustainable Ecosystem Solutions, University of Wollongong):

‘British graziers … cleared country using fire. The Snowgums tell the story: a seven-fold increase in fire scars when the invasion came’.

This use of fire has continued today, but does it reduce the flammability of the mountains? Philip points out that fuel reduction only brings a short reprieve:

‘Recently, I looked at every fire mapped across these mountains for nearly 60 years, and I found one thing in common from the foothills to the peaks: fire has always followed fire. For a couple of years, it brought quiet, then the undergrowth made the forests up to eight times more likely to re-burn for the next couple of decades until it self-thinned. So why did anyone burn it if this was the result?’

Keeping fire out may be the solution in snow gum forests

One significant piece of research that should inform our understanding about fire on snow gum forests looked at the impacts of fires on Lake Mountain and the Buffalo Plateau. The report How snow gum forests and sub-alpine peatlands recover after fire was written by Fiona Coates, Philip Cullen, Heidi Zimmer, James Shannon. They used the long unburnt Baw Baw Plateau as an example of what these systems could be like in the absence of fire events.

They found that:

  • Even areas that have been subjected to hot and very destructive wildfire, such as on the Lake Mountain plateau during the 2009 Black Saturday fires, can be expected to recover – provided we can keep fires out of these systems. However, this will take time. For instance they suggest it will take the forests at Lake Mountain at least 70 years to return to pre-fire structure. No specific management needs to be undertaken to aid this process beyond excluding fires
  • The researchers repeatedly note that there are serious doubts about the value of fuel reduction burning in these forests. They note that low intensity fires negatively impact on tree resprouting ability
  • Repeated fires change the character of snow gum forests, creating a multi stemmed forest of shorter trees. That is, forests get denser, with more of a ‘Mallee’ aspect to how the trees grow. They call this ‘potentially irreversible degradation of stand structure’, which has already happened to the extent that old growth snow gum forests are now rare. They note that the traditional open forest structure of snow gum forests will not be able to develop if there are repeated fires, as the result over time will be that forests will become dominated by lots of small stemmed trees rather than a ‘traditional’, open snow gum forest
  • Repeated fires can also inhibit the ability of trees to store carbon above the ground.
  • They say that ‘fire exclusion is imperative to preserve landscape quality and representation of long unburnt snow gums’
  • They recommend that current ‘fire and cattle exclusion policies’ at places like Mt Buffalo and Lake Mountain be continued. They note that cattle grazing can drive the creation of multi stemmed trees, in the same way that fire tends to, again driving the forest towards a multi stemmed and immature form. Exclusion of cattle is also very important for recovery of burnt areas of peat land
  • Older, more open snow gum forests are better at collecting water and ensuring regular run off, retaining soil moisture and snow accumulation.

 

Impact of fires on the upward spread of snow gums

Fires impact on mature trees and the resulting growth of seedlings may mean that snow gums start to colonise adjacent alpine vegetation.

David Turner, in his research carried out for his Masters of Environment thesis (School of BioSciences, University of Melbourne) titled Treeline physiognomy following wildfire in the Victorian Alps, Australia investigated snow gum seedling establishment above the treeline after fire.

He found that new seedling growth was greater after fire compared to locations long absent of fire. ‘Model probabilities estimate a 22% chance of seedling establishment four metres above treelines that are burnt, compared to only a 1% chance in unburnt locations’. (He does note that the number of seedlings, which was modelled to increase after fire, is controlled by the amount of litter and competition found at the site. Low levels of litter and competition facilitate maximum seedling growth). 

One significant outcome regarding frequent burning showed that optimal tree ages that influence seedling establishment were found to be between 24 and 42 years of age. If climate change subsequently reduces fire frequencies to less than (for example) every 20 years, then seedling numbers may actually fall.

Repeat burn times that outpace snow gums (Eucalyptus pauciflora) reaching their optimal reproductive maturity age may subsequently have dramatic effects on the Victorian treeline.

His research suggests that the Victorian treeline physiognomy has slightly changed due to the 2003 alpine fires. 

 

Climate impacts

Sadly, the fact is that climate change is making fire seasons worse. As noted by the Victorian government’s report ‘Climate Science Report 2019’,

‘There has been an increase in dangerous fire weather and the length of the fire season across southern Australia since the 1950s. Fire weather in Victoria is largely measured using the Forest Fire Danger Index (FFDI). This index estimates the fire danger on a given day based on observations of temperature, humidity, wind speed and fuel (based on factors including recent temperature and rainfall). Although considerable year-to-year variability also occurs, there is a trend in more recent decades towards a greater number of very high fire danger days in spring’.

So, regardless of how we manage forests with regards to fuel reduction treatment, we will be facing worse and longer fire seasons. It would appear that one key strategy will be to keep fire out of snow gum woodlands wherever possible, so these systems can age and become less fire prone.

Regular and repeated fires kill snowgums. So if we want to see snow gum forests continue we need less fire, not more, even low intensity fuel reduction burns. According to research by Tom Fairman, Associate Professor Lauren Bennett and Dr Craig Nitschke, of the University of Melbourne:

‘We found that the lignotuber continued to re-sprout very well after one fire, but after two and three fires, the number of new sprouts significantly declined. The level of whole-tree death (that is, the stems and lignotuber dying) was fairly low following one and even two, fires; however, after three successive fires, on average half of all trees in our plots were dead. In some plots, this figure was as high as 80 per cent of all trees’. (source).

A study in the journal Austral Ecology provides the most comprehensive analysis ever performed of the fire history of forests in the Australian Alps. This is a significant piece of work because it says that unburnt forests are less fire prone than those that have been recently burnt.

This has implications for how we manage these forests and woodlands. The current widely held assumption is that by reducing fuel loads, fire reduces the flammability of most eucalypt-based forests.

The study, by Dr. Philip Zylstra of the University of Wollongong (and available here) says:

‘The study provides an evidence base for fire management in the Alps that is based on observed reality rather than theoretical concepts.

‘Throughout the period for which fires have been consistently mapped across the Australian Alps National Parks, they have been smaller and less severe in long unburnt forests’. This is consistent across the five broad forest formations that cover the Alps’ (these forest types are Tall Wet Forest, Open Forest, Subalpine Forest and Woodland, Dry Open Forest and Low, Dry Open Forest).

The study looked at fires in five key forest types in the Alps and assessed how fire frequency changed over time. To take the example of snow gum woodlands, after a fire passes through, they are unlikely to burn for 6 years after fire, then more flammable until 25 years old. However, ‘forests older than this are 2.3 times less likely to burn than younger forest’. A similar pattern can be observed in the other forest and woodland types.

Ben Keaney, in his PhD research titled Bogong Moth Aestivation Sites as an Archive for Understanding the Floral, Faunal and Indigenous History of the Northern Australian Alps  noted that climate change is already impacting on the mountains, and could drive forests into a more scrubby, flammable form, and that this has implications for land management practises like fuel reduction burning:

‘Structural change of the vegetation due to human induced climate change is a real threat to sub-alpine ecology. Pryor (1939) described the possible extent of high country degradation from burning as two extremes, that is a slightly damaged forest that is more or less undisturbed, to a barren waste of eroded mountains with a sparse cover of plants. This is poignant as a prediction for the natural land managers under the effects of anthropogenic climate change, where the flammability of the forest can drive ecological change of vegetation away from a forest form into a scrub form, a point that should be taken to account in the prescription of fuel reduction burns. Predictions of the effect of climate change on the ACT include fires with higher intensities, with reduced inter- fire intervals and that are more prone to spread (Cary, 2002)’.

The take home message seems to be that if we can reduce the frequency of fire at a landscape level in these ecosystems through the juvenile ‘danger’ period when there is a lot of vigorous re-growth, they become less fire prone after a period of 14 to 28 years (depending on the forest type). This means that older forests should be left alone rather than burnt to reduce fuel load, and younger forests should be encouraged to mature rather than being treated with fire to keep them permanently in a juvenile/ more flammable stage in their growth.

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This forest (Mountain Gum?) near Lost Plain had a light fire through it in 2019. It cleared out the understory and moved into the canopy in some areas

Implications for fire management

What are the implications for fire fighting in the alpine country? The key message is that we need to keep fire out wherever possible. Locking in more intense fuel reduction regimes are unlikely to make snow gum forests less fire prone, for the reasons outlined above.

1/ More fire fighting resources. Most fires in the Alps start as a result of lightning strikes – that is they start small at a specific point. The aim must be to hit these fires while they are small.

This requires additional fire fighting resources at the state level to tackle these fires as soon as possible, before they grow and become difficult to contain. DELWP and Parks Victoria firefighters are well trained and equiped to fight these fires and do a great job of tackling them. But we clearly need more firefighters.

As one example of how the system gets overwhelmed: on New Years Eve 2019/20 a lightning storm passed over the Victorian Alps, starting many fires. DELWP and PV crews quickly mobilised to put these fires out before they grew, but some more remote fires were not able to be contained and subsequently grew into large blazes (such as the fire at Mt Tabletop near Mt Hotham, which eventually joined with other fires started by lightning and is now more than 42,000 hectares in size).

Stay governments should consider increasing the number of remote area fire fighters for the next fire season.

2/ Minimise burning for asset protection. There are various human settlements in alpine areas, which need to be protected from fire, especially the ski resorts. Doing fuel reduction burning is sometimes used as a last resort before fire fronts hit. The longer term implications of this need to be considered. Fire breaks are widely used in the Alps to limit the movement of fire. Research should be carried out to determine the relative value of fuel reduction, use of fire breaks, and other asset protection work around human settlements.

3/ Consider the development of a volunteer remote area fire fighting force. The Country Fire Authority (CFA) and Rural Fire Service (RFS) do a remarkable job of protecting land and community from fire. While they are primarily responsible for fires on private land, they are often active in fighting fires on public land. But their equipment  (trucks) is often too heavy for deployment to remote areas with rough tracks and they are not directly trained or resourced to work in remote areas.

Is it time to develop a new fire fighting force that is specialised in remote area fire fighting? It could be part of RFS/ CFA or be a new stand alone entity, and would work closely with public land firefighters who are already doing this work. They could be trained in the same way that PV and DELWP prepare their rappel and hover exit crews (specialist firefighting roles performed in remote locations).

There has previously been a similar group in Tasmania, called the Smoke Walkers. The Smoke Walkers were volunteers, mostly bushwalkers, who were deployed to remote areas in Tasmania’s World Heritage Areas in instances where lightning had started fires that had not yet turned into major blazes.

In light of the scale of this summer’s fires, this is an idea that needs consideration in NSW and Victoria. A proposal can be found here.

Bushfire in the Victorian Alps

Bushfire in the Victorian Alps

The 2019/20 Black Summer Bushfires, where significant fires were burning in northern and southern NSW, eastern Victoria, South Australia and Western Australia at the same time, has stretched the nation’s resources and capability to respond to such events. A clue to the reason for the extensive fires can be found in the data recorded by the Bureau of Meteorology. Much of eastern Australia in 2019 was:

  1. The driest on record for the three year period January 2017 to December 2019. Mean national rainfall was 100 mm lower than the previous driest three-year period (1965-67).
  2. 2019 was the warmest year on record for Australia.
  3. Severe fire weather conditions (national annual accumulated Forest Fire Danger Index) throughout 2019 were the highest they have been since national records began in 1950.

In Victoria, >1.5M ha of land was burnt, mostly in the east of the State, with profound impacts on many native animals, plants and landscapes.  Some fires did affect alpine areas, including at Mt Buffalo National Park and the Alpine National Park. The extent of fires (at January 2020) is shown below (in red). Importantly, it is obvious that fires have been frequent, extensive and – in some places – repeated since 2003. It is the frequency of fire (what ecologists call the ‘fire return interval’) that will dictate the likelihood of ecosystem recovery. Looking closely at the map, you can see some high mountain areas have been burnt in 2003 and 2020, while others have been burnt in 2013 and 2020, and others near Hotham Heights have been burnt in 2003, 2013 and 2019.

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Fire history map for the Victorian High Country, produced by Thomas Fairman.

Here’s a selection of photos that document the type of burning that has occurred in the Victorian Alps. The RCAAE will be monitoring the recovery of alpine ecosystems – utilising it’s network of long-term plots – to determine the ecological resilience of these areas.

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Burnt heathland and grassland, north of The Horn, Mt Buffalo

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Alpine heathland, grassland and wetland dominated by Sphagnum cristatum has been burnt at Mt Buffalo, south of The Horn

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Forested slopes have been burnt, south of The Horn, Mt Buffalo

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Obligate-seeding shrubs – like Grevillea australis – are killed by fire

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Hovea is a resprouting shrub, recovering from basal buds, Mt Buffalo

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Not all tussock grasses resprout well after fire. Here, Poa clivicola in an alpine grassland at Buckety Plain appears to have died when the canopy is consumed.

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Snowgum forests near Mt Cope have had their heathy understorey consumed by fire. Note the leaves of the trees have been scorched by the heat of fire rather than consumed by fire.

 

Maisie’s Plots, and Long-term Monitoring in the Victorian Alps

Scientific research in the Australian Alps has a long and rich tradition. In 1945, Maisie Carr (nee Fawcett) and Professor John Turner (from the University of Melbourne) established the first long-term monitoring plots in the Victoria Alps at Rocky Valley and Pretty Valley on the Bogong High Plains.

‘Rocky Valley’ is a 5-ha exclosure that was the first permanent plot to be established by Maisie. In January 1945, she selected a large area (a small catchment) on the upper slopes of Rocky Valley that contained a range of vegetation types—mossbed, snowgrass grassland, open heath, closed heath and a Carex-dominated late lying snowbank. A fence was erected to exclude cattle, and a range of permanent plots established to monitor vegetation recovery inside the fence.

‘Pretty Valley’ is a 0.4-ha exclosure (and adjoining control on the edge of the Pretty Valley catchment) that examined the impacts of cattle grazing on range condition in Poa-dominated grasslands. The State Electricity Commission of Victoria erected the fence in 1946 (using the local snow gums for fenceposts) and permanent transects were established. Point quadrats used to assess changes in vegetation composition, ground cover condition, and bare ground.

Pretty Valley Grassland
Fig 1. Maisie Carr’s ‘Pretty Valley Grassland’ plot in 2009. Note evidence of bushfire in the background.

Both plots have been maintained to the present day and are now an integral component of the La Trobe University led Research Centre for Applied Alpine Ecology’s long-term plot monitoring network. Building on Carr and Turner’s work, RCAAE alpine ecologists have expanded the number of sites over the decades to include the wider Victorian Alps. An ongoing surveillance regime examines the impacts of bushfire, introduced ungulates such as sambar deer, exotic plant invasions and climate change on rare species persistence, plant community dynamics, and landscape function.  With a succession of alpine scientists working on an expanding network of permanent plots (today there are more than 50), the value of the RCAAE Plot Network for documenting environmental change is inestimable.

To curate the long-term data, a purpose-designed database was commissioned. With the assistance of La Trobe University’s Department of Computer Science and (partly) funded by the Terrestrial Ecosystems Research Network (TERN; 2012-2017), the database has become the premier repository for long-term scientific data from the Victorian Alps. Over 70 yrs of monitoring at Maisie’s Plots have been captured in the database, providing a record of the sites’ vegetation change, represented by an exceptionally diverse set of population-related observations totalling over 200,000 records. More than 35 yrs of (near) annual population monitoring of the threatened Mountain Pygmy Possum has been entered into the database, along with data on roadside weed invasions, shrub dynamics in open heathlands spanning multiple decades, snowpatch vegetation change since 1992, and microclimate records (including soil and air temperature) since 2003.

Rocky Valley Bog
Fig 2. Maisie Carr’s “Rocky Valley Bog’ plot in 1999, showing the distribution of Sphagnum moss (grey), interspersed with steams and pools (black).

These exceptional data provide an invaluable source of information. “The RCAAE database allows scientists to answer questions about long-term alpine ecosystem dynamics and their vulnerability to changing patterns of climate, fire and land-use pressure,” says Dr John Morgan, member of La Trobe University’s Research Centre for Applied Alpine Ecology. “Getting data into a database is a fantastic achievement, and one that needs ongoing support.”

Long-term research also needs to be supported to provide an evidence base for management decisions. The type of detailed monitoring undertaken in the Victorian Alps allows the RCAAE to anticipate environmental change and to inform how best to manage the land for sustainable use.  According to Dr Dick Williams of Charles Darwin University, and an inaugural RCAAE member, the understanding gained from this research has also highlighted its current limitations. “70 years is a short time in the Alps, and there are still many things we don’t understand. Long-term monitoring will always be vital for increasing our understanding, anticipating change and managing the alpine environment for sustainability.”

Mt Magdala Summit Survey
Fig 3. An example of one of the new plots maintained by the RCAAE – “Mt Magdala Summit Survey Plot’. A network of 14 alpine summits are monitored at 5-yr intervals to assess the effects of climate change, fire disturbance, and exotic organisms on plant community composition and abundance.

The value of long-term research is often under-recognised. But sometimes being present in a landscape and taking repeat measures through time is the most innovative and important thing one can do to understand that landscape, how it is changing, and how it is likely to change in the future. The Australian Alps – small and vulnerable as they are to climate change and exotic invasions – are among Australia’s best monitored ecosystems, and it is from this evidence that trends, trajectories and change can be placed into context. Maisie Carr and John Turner could never have imagined such an enduring outcome of their work when the first fence-post was sunk at Rocky Valley in 1945.

 

For more information on the Victorian Long-term Alpine Plots, please contact Dr John Morgan at alpine.ecology@latrobe.edu.au

 

Maisies Sign

Fig 4. Still going strong. Maisie’s ‘Pretty Valley’ plots are due to be monitored again in 2023. Documenting the ongoing changes in the vegetation inform managers about successional dynamics in alpine rangelands, ongoing effects of drought, as well as providing a means for the early detection of new invasive plant species.

Honours research into the impact that a decline in bogong moth has on mountain pygmy possums

Claire Hutton is a new honours student at at La Trobe University studying with Dr Dean Heinze and Dr John Morgan. Below, Claire has written about her project and motivations for working in the alps.


My interest in the alps originates from two different aspects. Firstly, from a great appreciation for the beauty of mountains. And secondly, from the belief that the management of alpine environments should balance tourist access and the preservation of its ecosystems. My honours project focuses on two major species which rely on the perseverance of Australia’s unique montane conditions: bogong moth and mountain pygmy possum.

Bogong moth migrate in large numbers to the peaks of the Snowy Mountains and the Victorian Alps, including the Bogong High Plains and Mount Buller, every spring. This, in itself, delivers a huge influx of prey to many species, such as mountain pygmy possum. These possums need to gain sufficient weight in the space of only a few months to carry them through their winter hibernation. Traditionally, they do this by capitalising on the extensive bogong moth availability, particularly in October and November; therefore these possums are believed to be dependent on the bogong moth. Over the last two summer, however, there have been anecdotal reports indicating a crash in bogong moth population, raising concern over the impact this decline could have on mountain pygmy possum, among other species.

This study aims to determine both the abundance of bogong moth and the composition of mountain pygmy possum diet, specifically the proportion of bogong moth to other carnivorous and herbivorous prey in faecal samples. This will give insight into the degree of specialisation of these species’ predator prey relationship.

Data collection will take place through field surveys at Mount Little Higginbotham and Mount Buller across the coming snow free season. Specifically, collections will be monthly from October to February capturing the traditional peak in bogong moth alpine population in Spring and allowing for comparisons across early and late summer. Environmental moth abundance will be measured using light traps; diet composition will be assessed through scat collection from possum trapping and subsequent laboratory analysis.

This research may find that moths are not arriving in large numbers. This may reflect the recent drought or agricultural changes in their lowland breeding grounds. This may lead to a reduced proportion of bogong moth being consumed. This study will be able to determine if other arthropods are predated upon in lieu, given that alternative species are available. However, there may be significant impacts on possum health and reproduction if bogong moth cannot be substituted with species which are both available in high numbers and rich in energy.

This study will contribute to records of bogong moth populations as there is currently very limited published data. It will also highlight an additional, potential threat to mountain pygmy possum and the importance of maintaining these ecosystems for supporting the species comprising them.

– Claire Hutton

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Honours student investigating the diet of sambar deer on the Bogong High Plains

Matthew Quin is an honours student currently investigating the diet of Sambar Deer on the Bogong High Plains in Victoria. Although it is recognized that introduced deer cause significant detrimental changes to natural ecosystems, the ability of Sambar deer to aid or limit native and exotic plant species through dietary foraging and endozoochory (the process of moving plant seeds via faecal matter) is still relatively unknown.

Matt is investigating Sambar deer diet through DNA metabarcoding of faecal pellets, an advancing technology used for distinguishing multiple plant species within a sample. Additionally, the role of Sambar deer as plant-seed dispersers will be assessed through glasshouse germination trials of faecal pellets, providing insight into which plant species, whether native or exotic, are capable of surviving the digestive system and prospering from the endozoochory processes of Sambar deer.

Considering threats currently faced by the Victoria Alps as a result of climate change, this project has great importance for understanding additional Sambar deer browsing effects on Bogong High Plains ecosystems, and the prospect of plant species invasion as a result of endozoochory.

Matt Quin and plants germinating from deer pellets