Like cats and dogs: dingoes can keep feral cats in check

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Feral cats are linked to the extinction of at least 20 Australian mammals.

Mike Letnic, UNSW and Ben Feit

The role of dingoes in the Australian landscape is highly debated between ecologists, conservationists and graziers. They kill livestock, but also hunt introduced animals and keep kangaroo populations in check.

Now new research sheds more light on the benefits dingoes bring to the outback. For the first time, our research clearly shows that dingoes suppress feral cat numbers.

Our research, published recently in Ecosystems, used the world’s largest fence to compare essentially identical environments with and without dingoes. Over the course of the six-year study, dingoes drove down cat numbers – and kept them down.

Read more:
A hidden toll: Australia’s cats kill almost 650 million reptiles a year

Feral cats are out of control

Feral cats are a serious conservation threat. They have been linked to the extinction of at least 20 mammal species in Australia and threaten the ongoing survival of more than 100 native species.

For our study, we asked whether “top-down” pressure from dingoes (through direct killing and competition for food) had a greater influence on controlling cat numbers than “bottom-up” effects (the availability of shared food sources preyed on by cats).

Dingoes drive down the population of introduced animals.
Kim/flickr, CC BY-SA

We conducted our study by comparing the numbers of dingoes, cats and their major prey species on either side of the dingo fence in the Strzelecki Desert. The fence runs along the borders of New South Wales and South Australia and was originally built to exclude dingoes from sheep grazing lands in NSW.

The state border follows the longitude line 141 east, so the fence does not demarcate any natural boundary. It simply cuts a straight line through sand dunes with similar landforms and vegetation on either side. Thus the dingo fence provides a unique opportunity to study apex predators’ effects on ecosystems: dingoes are common on the SA side, “outside” the fence, whereas on the NSW “inside” of the fence, dingoes are rare due to intensive persecution by humans.

Read more:
Let’s move the world’s longest fence to settle the dingo debate

We collected data from sites on either side of the fence in the Strzelecki Desert, at roughly four-month intervals between 2011 and 2017. Dingo and cat scat was collected at each site, to analyse and compare diets, and spotlight searches were used to record numbers of dingoes, feral cats, as well as two of their common shared food sources: rabbits and hopping mice.

Spotlight surveys revealed dingoes to be virtually absent from study areas inside the fence, with only four dingoes recorded during the study. Where dingoes were rare inside the fence, cat numbers closely followed fluctuations of their prey species consistently over the six-year span of our study. As prey numbers increased, cat numbers also increased, and similarly as prey numbers declined, cat numbers also declined.

A feral cat in outback Australia.

Outside the fence, where dingoes were common, it was quite a different story. There, cat numbers were consistently lower, with numbers of both cats and dingoes following fluctuations in prey numbers across the first two years of the study. However, from 2013 onward, dingo numbers remained high and matched trends in their prey numbers for the remainder of the study.

During this time, cat numbers remained low, and by the end of 2015, cats had virtually disappeared from our study sites outside the fence and were not recorded during spotlight surveys between November 2015 and the end of our study in July 2017.

The most likely explanation for this drastic reduction in cat populations is through interference competition – either by dingoes killing some cats or by scaring others away from habitats in which they would usually hunt. Indeed, we occasionally found cat remains in dingo scats, which suggests dingoes prey on cats.

Although our scat analyses indicated that dingoes and cats eat similar foods, there was no evidence that competition for food was a major factor in how dingoes reduce cat populations. This is because prey were plentiful outside the fence, where dingoes were common and cats were rare.

Read more:
Why do some graziers want to retain, not kill, dingoes?

This research show how dingoes can help conservation efforts by suppressing feral cat populations. It adds to previous work showing dingoes are important in maintaining healthy ecosystems, as they reduce and eradicate feral herbivores like pigs and goats, and stop kangaroos from overpopulating districts.

This article was updated on April 5 to credit Ben Feit as a co-author.The Conversation

Mike Letnic, Professor, Centre for Ecosystem Science, UNSW and Ben Feit, Post-doctoral researcher

This article is republished from The Conversation under a Creative Commons license. Read the original article.


Dingo dinners: what’s on the menu for Australia’s top predator?

Tim Doherty, Deakin University; Chris Dickman, University of Sydney; Dale Nimmo, Charles Sturt University; Euan Ritchie, Deakin University, and Thomas Newsome, University of Sydney

The dingo is Australia’s largest land-based predator, occurring across most of the mainland and on many nearshore islands.

Our new research, published in the journal Mammal Review, reveals the breadth and diversity of dingo diets across the continent.

We compiled and analysed 73 sets of data, containing details of more than 32,000 dingo droppings or stomach contents, to document the range of different species that dingoes eat, and how their diets vary between different environments.

A wide-ranging diet

We found that dingoes eat at least 229 vertebrate species. This includes 62 small mammals (less than 500 grams in mass), 79 medium-sized and larger mammals, 10 species of hoofed mammals, 50 birds and 26 reptiles. Dingoes also eat insects, crustaceans, centipedes, fish and frogs.

The true number of species is likely to be much higher because dingo diets have been poorly studied in many parts of Australia, such as Cape York Peninsula.

Read more:
Dingoes do bark: why most dingo facts you think you know are wrong

Large (at least 7kg) and medium-sized (0.5-6.9kg) mammals were the most common components of dingo diets, followed by small mammals, rabbits, arthropods, reptiles, birds and hoofed animals.

Average occurrence of eight food types in the diet of dingoes. Values represent the percentage of droppings/stomachs that contained each food type.

A range of introduced pest species also feature in dingo diets, including deer, goats, rabbits, hares, black rats, house mice, foxes and cats. In recent decades, the occurrence of sambar deer in dingo diets has increased as this invasive species has expanded its range.

Dingoes also eat sheep and cattle, although dietary samples are unable to distinguish between predation and scavenging, and hence tell us little about dingo impacts on livestock production. Dietary samples also do not reveal instances of dingoes killing livestock without eating them.

Regional variation

We found that what dingoes eat depends on where they live. For instance, in arid central Australia, birds, reptiles, rabbits, small mammals and insects form major parts of dingo diets. In contrast, these food groups are less important in temperate and subtropical eastern Australia, where medium-sized and large mammals such as kangaroos, bandicoots and possums are more important.

Frequency of different food groups in dingoes’ diet. Each circle represents a study and is scaled proportionally with dietary occurrence; larger circles represent a higher frequency of that food type. Top row: arthropods and small mammals (less than 500g); middle row: reptiles and medium-sized mammals (0.5-6.9kg); bottom row: rabbits and large mammals (at least 7kg).

The higher occurrence of medium-sized mammals in dingo diets in eastern Australia may be due to the lower extinction rates of native mammals there. In contrast, central Australia is a global mammal extinction hotspot, which probably accounts for the low occurrence of medium-sized mammals in dingo diets in arid and semi-arid areas.

Nonetheless, one medium-sized mammal was a major food item for dingoes in arid areas: the European rabbit. In some areas, more than 50% of dingo droppings or stomachs contained the remains of this invasive species. It is possible that native medium-sized mammals previously constituted a major part of dingo diets in arid Australia, but have since been replaced by rabbits.

Local prey availability plays a major role in determining what dingoes eat. For instance, in the Tanami Desert, reptiles were most common in dingo diets during warmer months when they are most active. However, very few studies have collected data on prey availability, partly because of the sheer number of different animals that dingoes eat.

Threatened species

Dingoes kill or eat at least 39 native species that are classed as threatened or near-threatened on the IUCN Red List. These include the northern quoll, golden bandicoot and bridled nailtail wallaby.

This tally is higher than the number of threatened species in feral cat diets (based on a previous study that used similar methods), even though cats eat almost twice as many different species overall as dingoes (400 and 229, respectively).

Read more:
Why the WA government is wrong to play identity politics with dingoes

Today’s threatened native species co-existed with dingoes for a long time before European colonisation, which means they were able to withstand dingo predation without going extinct.

But now a combination of small population sizes of some threatened species and exacerbating factors such as habitat loss, foxes and cats means some threatened species could be vulnerable to even low levels of dingo predation. Predation by dingoes should therefore be a key consideration when attempting to conserve or restore threatened species.

Dietary studies are one way we can understand how dingoes interact with other species. Our study also highlights that we still have much to learn about our native top predator. In many parts of Australia, the favourite foods of dingoes are still a mystery.

The authors acknowledge the contribution of Naomi Davis, Dave Forsyth, Mike Letnic, Russell Palmer, Joe Benshemesh, Glenn Edwards, Jenny Lawrence, Lindy Lumsden, Charlie Pascoe, Andy Sharp, Danielle Stokeld, Cecilia Myers, Georgeanna Story, Paul Story, Barbara Triggs, Mark Venosta and Mike Wysong to this research.The Conversation

Tim Doherty, Research Fellow, Deakin University; Chris Dickman, Professor in Terrestrial Ecology, University of Sydney; Dale Nimmo, Associate professor/ARC DECRA fellow, Charles Sturt University; Euan Ritchie, Associate Professor in Wildlife Ecology and Conservation, Centre for Integrative Ecology, School of Life & Environmental Sciences, Deakin University, and Thomas Newsome, Lecturer, University of Sydney

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Why the WA government is wrong to play identity politics with dingoes

Bradley Smith, CQUniversity Australia; Euan Ritchie, Deakin University, and Lily van Eeden, University of Sydney

Australia’s Commonwealth Coat of Arms depicts two iconic native animals – the kangaroo and the emu. Both are unquestionably fair dinkum Aussies, unique to this continent and having lived here for a very long time. A “very long time”, according to Australian legislation (the EPBC Act 1999), is any species having been present since before the year 1400.

But in Western Australia, under the state’s Biodiversity Conservation Act 2016, no native animal is guaranteed protection. The Act includes a caveat whereby the relevant minister may determine that a native species is in fact, not.

Read more:
Dingoes do bark: why most dingo facts you think you know are wrong

This week, WA’s environment minister Stephen Dawson did just that, declaring that from January 1, 2019, the dingo, Australia’s native canine, will no longer be classified as native fauna.

The dingo does meet the federal government’s criterion, having lived in Australia as a wild canid for an estimated 5,000 years. But under the planned changes in WA, the dingo will lose its current listing as “unprotected fauna”, and will from next year be considered indistinguishable from either the common domestic dog or feral dogs.

What is a species anyway?

According to the biological species concept, a species is a group that has the ability to interbreed and produce viable, fertile offspring. Dingoes, dogs and other canids do interbreed (or “hybridise”), and indeed this is one of the key reasons why the pure dingo is listed as vulnerable by the International Union for the Conservation of Nature.

But this ability to hybridise is also one of the main justifications cited by the WA government in its decision to revoke the dingo’s citizenship (the fact sheet has since been removed from the website, but can be accessed here). The rationale is that if dingoes and dogs are technically the same species, why should dingoes get special treatment?

However, the biological species concept is problematic when applied to canids. If you lump dingoes and dogs together because they readily interbreed, then logically we must do the same for wolves, coyotes, jackals or other canids that can also interbreed (and have done for millenia).

It’s hard to imagine anyone seriously suggesting that a grey wolf and a pug are the same species. This suggests that this criterion alone is insufficient to solve the conundrum. Indeed, there are at least 32 different species concepts, clearly illustrating the difficulty of defining a single rule by which all organisms should abide.

Despite this, a recent paper that argues the biological species concept should be applied to dingoes, was cited as supporting evidence by the WA government. Adopting this narrow interpretation of taxonomy is perhaps somewhat premature. It ignores other investigations that provide evidence to the contrary. Given the contention around defining species, it seems unwise to determine the species status of dingoes independently of other, more comprehensive evidence and argument.

Distinguishing dingoes

All canids share similarities, but their differences are also many and marked. The dingo can be distinguished from other dogs in various ways: their appearance, anatomy, behaviour, their role in ecosystems, and their genetics (their evolutionary history and degree of relatedness to other species). Dingoes seem to be largely devoid of many of the signs of domestication.

It is therefore reasonable for the dingo to be considered separately from wolves and domestic dogs, while also acknowledging that they all occupy the same broad species classification, Canis lupus.

Having lived in Australia as free-living, wild populations for around 5,000 years almost exclusively under the forces of natural selection, and separately from any other dog lineage until European arrival, there is no notion of the dingo as a domestic animal gone feral. To classify dingoes as nothing more than “feral domestic dogs” expunges their unique, long and quintessentially wild history. Dingoes are not ecologically interchangeable with any other type of dog, either wild or domesticated.

Australia’s dingo is a recognisable species.
Angus Emmott

Labelling the dingo as a feral domestic dog changes their legal status and removes any current obligations for developing appropriate management plans. This demotion of status could lead to intensified lethal control. Indeed, control may even be legally mandated.

In the absence of thylacines, mainland Tasmanian devils, and other apex predators, the ecological role that the dingo plays in the Australian landscape is vital. Dingoes help to control kangaroo and feral goat populations, and in some cases foxes and cats as well.

Read more:
Why do dingoes attack people, and how can we prevent it?

Given WA’s remoteness, it remains one of the few bastions of pure dingoes, and as such it presents an opportunity to seek ways to protect them rather than pave the way for their removal. The WA government’s decision also sets a dangerous precedent for the management of dingoes, and indeed other contentious native wildlife, elsewhere in Australia.

How we choose to classify plants and animals might sound like dry science. But it has genuine implications for policy, management and conservation. Our scientific naming systems are vital for helping to organise and understand the rich biological diversity with which we share the planet, but it is important to remember that these systems are informed not just by biology but also by our values.

In this case, economic and political interests appear to have been favoured over wildlife preservation, and given Australia’s unenviable conservation record this is deeply concerning.The Conversation

Bradley Smith, Senior Lecturer in Psychology, CQUniversity Australia; Euan Ritchie, Associate Professor in Wildlife Ecology and Conservation, Centre for Integrative Ecology, School of Life & Environmental Sciences, Deakin University, and Lily van Eeden, PhD Candidate in Human-Wildlife Conflict, University of Sydney

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Why do dingoes attack people, and how can we prevent it?

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Dingoes are usually solitary, but can forage in groups near human settlements where food is abundant.
Klaasmer/Wikimedia Commons, CC BY-SA

Bill Bateman, Curtin University and Trish Fleming

The case of Debbie Rundle, who was attacked by dingoes at a mine site in Telfer, in Western Australia’s Pilbara region, evokes our instinctive horror at the idea of being attacked by wild animals.

Rundle suffered severe leg injuries in the incident, and said she feared she may have been killed had her colleagues not come to her aid.

Read more:
Azaria Chamberlain inquest: forget the dingo jokes and recognise Lindy’s trauma

We know that there are carnivores throughout the world with the potential to kill us. And while most of us will never come face to face with a hungry wolf, lion, tiger or bear, such attacks do unfortunately still occur.

In the scale of things, such attacks are very uncommon – although that is little consolation to the victim. Australia’s dingoes are no exception; despite some infamous examples, dingo attacks on humans are mercifully rare. But people will still understandably want to know why they happen at all, and what can be done to prevent them.

Why do wild animals attack?

Research on wolf attacks shows that, absent the influence of rabies which can increase wolves’ aggression, two common factors associated with attacks are that they often happen in human-modified environments, and by animals that are habituated to human presence.

These two variables are obviously linked: many species of mammalian carnivore are highly adaptable, and soon learn that human settlements are sources of food, water and shelter.

These human resources can have a profound effect on the behaviour of wild animals. Abundant human food often reduces animals’ aggression towards one another, and can result in the presence of much larger numbers of individuals than normal.

This is equally true of dingoes. Although they are usually observed alone, it is not uncommon to see groups of ten or more dingoes foraging at rubbish dumps associated with mine sites in the Tanami Desert of central Australia. There are thought to be around 100 dingoes that forage in and around the Telfer mine where Rundle was attacked.

Waste food may inadvertently entice animals to human settlements, and this may lead to predators becoming habituated to human presence. In Canada, a young man fell victim to a wolf attack at a mine site; the local wolves were reported to be used to humans, and would even follow rubbish trucks to the tip. They may have come to associate human smells with the provision of food.

Animals that are habituated to humans lose some of their natural wariness towards them. This is typical of many animal species that adapt to urban habitats, and while this may be an appealing trait in squirrels or garden birds, it can be quite different if the animal is a predator capable of attacking a human.

Coyotes can be dangerous, especially when they get used to living in human environments.
Marya/Flickr/Wikimedia Commons, CC BY-SA

In the United States, there have been many reports of coyotes attacking humans. The coyote, like the dingo, is reasonably large (typically weighing 10–16kg) and can be found in close association with urban areas. The coyote’s natural range has expanded as wolves (their competitor) have dwindled, and their numbers have increased in and around cities where they find copious and consistent supplies of food and water.

A survey of reported attacks on humans by coyotes showed that many were “investigative”, often involving the animal trying to steal something they perceived as food from the person. Other attacks by coyotes could be identified as “predatory”, in which the victim was pursued and bitten, and often occurred when the coyotes were in a group.

Read more:
Dingoes do bark: why most dingo facts you think you know are wrong

The Telfer dingo attack similarly appears to have been investigative – a young dingo climbed onto a table and grabbed Rundle’s phone. But the incident turned nasty when Rundle (perhaps understandably) followed the dingo that had her phone; this seemed to trigger a defensive or predatory attack from two other dingoes.

On Queensland’s Fraser Island, more than half of the recorded aggressive incidents by dingoes towards humans happened when the person was walking or running, suggesting that a “chase” response may have been involved.

The Telfer site, like other mine sites, has strict rules about putting waste food in bins, and managers have been proactive in training workers to not feed dingoes, in an attempt to prevent just such attacks. Rundle certainly seems to have followed these rules.

Unfortunately, in her case, other variables contributed to the attack – an investigative approach by one dingo that stole an item (that may have smelled of food) seems to have turned into an aggressive group attack when she followed the animals.

Read more:
Want dingoes to leave people alone? Cut the junk food

What can we do to prevent such attacks? Mine site managers already do much to reduce the likelihood of such incidents by reducing dingoes’ access to food. Fencing off eating areas or storing food in cages – as is done at Fraser Island – can help in this regard.

Interestingly, many people believe that it is best not to act aggressively when they encounter a large carnivore, but in reality it depends on the species. For wolves and pumas, the best tactic seems to be to shout and throw objects to put them off.

The ConversationUltimately, the onus is on individual people to be aware of the potential danger of wild predators, and always to treat them with wariness and respect.

Bill Bateman, Senior Lecturer, Curtin University and Trish Fleming, Associate Professor

This article was originally published on The Conversation. Read the original article.

Thinking big gives top predators the competitive edge

File 20170523 7361 1hgbqew
Dingoes can help manage devastating red fox and feral cat numbers, but only if we let enough of them live in key areas.
Bobby Tamayo, Author provided

Thomas Newsome, Deakin University

Dingoes could be the key to controlling red foxes and other invasive predators, but only if we encourage them in large enough numbers over a wide enough area, our research shows.

Interest in re-introducing or restoring top predators, like dingoes and wolves, has been fuelled by recent studies demonstrating their important roles in their ecosystems. They can especially be vital in suppressing the abundance of lower-order competitors or “mesopredators”, like red foxes and possibly feral cats (which can have devastating effects on native species).

But researchers have found top predators aren’t always successful in reducing mesopredator numbers. Until now, such variation has been linked to human presence, land-use changes and environmental factors such as landscape productivity.

However, our research, published yesterday in Nature Communications, found that a key factor for success is high numbers of dingoes and wolves across their natural range.

The density effect

If you look at how species are typically distributed across a landscape – their range – ecological theory predicts there’ll be lower numbers at the outer edges of their range.

If you do need large numbers of top predators to effectively suppress mesopredators, the core of their range is potentially the best place to look.

We tested this idea, looking at the dingo in Australia and the grey wolf in North America and Europe. The mesopredators included the red fox in Australia, the coyote in North America and the golden jackal in Europe.

We looked at three regions in our study. Predator distribution is shown for: a) coyotes (hashed) and grey wolves (orange) in Saskatchewan, North America (present day); b) golden jackals (hashed) and grey wolves (orange) in Bulgaria and Serbia (present day); and c) red foxes (hashed) and dingoes (orange) in Queensland, Australia (in the 1950s).
Predator images: Doug McLaughlin; Bobby Tamayo, Harley Kingston/flickr, Larry Lamsa/flickr

We used information from bounty hunting programs, as these provide data on predator numbers across a wide geographical area. In the case of Australia we used historic data from the 1950s, as this is the most recent reliable information about red fox and dingo distribution. The actual population numbers of red foxes and dingoes have changed substantially since then, but the nature of their interactions – which is what we were investigating – has not.

We determined that top predators exist in higher numbers at the core of their ranges in comparison to the edges. We then looked at mesopredator numbers across the range edges of their respective top predator.

Predator bounties and top predator range edges in each continent. The number of bounties (representing the number of animals killed) are given for each hunting unit in North America (collated from 1982 to 2011) and Europe (collated from 2000 to 2009), whereas each square in Australia represents the number of bounties in a 100-by-100km area (collated from 1951 to 1952). Top predators are in a–c. Mesopredators are in d–f. Darker colours within each hunting unit indicate greater bounty return numbers and, by inference, a higher abundance for the respective predator. Dashed black lines indicate top predator range edges. Australia was divided into two sections for the analysis (east and west) as shown.

The results, which were consistent across the three continents, suggest that top predators can suppress mesopredators effectively (even completely) but only in the core of their geographic range, where their numbers are highest.

In other words, abundant top predators can exert disproportionate mesopredator control once their numbers increase past a certain point.

Example of the results from Australia (western side of Queensland). The blue lines indicate the abundance of each predator (note that the values on the y-axis are scaled so do not reflect actual numbers). The black dashed line indicates where there is a sharp change in predator abundance (the breakpoint). The red dashed lines indicate 95% confidence intervals (a measure of uncertainty) either side of the breakpoint. Distance values less than zero relate to areas outside the dingoes’ range, while distance values greater than zero relate to areas within the range. In summary, abundances of the red fox decline sharply as you move further into the range of the dingo.

The ‘enemy constraint hypothesis’

The relationship we uncovered is now formalised as the “Enemy Constraint Hypothesis”. It could apply to other predator dyads, where two animals compete for similar resources – even relationships involving parasites and pathogens.

Our findings are important for understanding species interactions and niches, as well as the ecological role of top predators. It could explain why other studies have found top predators have little influence on mesopredators: they were looking at the edge, not the core, of the top predators’ range.

This is a conceptual model of the Enemy Constraint Hypothesis. On the edge of a top predator’s range, mesopredator abundance should decline as top predator numbers increase. The breakpoint for the mesopredator indicates where their population nears zero. The breakpoint for the top predator indicates where their abundance starts to decline sharply on the edge of the range.

How many top predators do we need?

Dingoes can be vital for reducing red fox and possibly feral cat numbers. In our case studies the ranges of each top predator were limited primarily by human use of the land and intensive shooting, trapping and poisoning.

Killing pack animals like dingoes can fracture social groups, potentially altering their natural behaviour and interactions with other species. Future studies on predator interactions therefore need to consider the extent to which the animals are acting in response to human intervention.

If we want to benefit from the presence of top predators, we need to rethink our approach to management – especially where they are subjected to broad-scale control, as the dingo is in some parts of Australia.

The ConversationChanging our relationship with top predators would not come without its challenges, but high extinction rates around the world (and especially in Australia) clearly indicate that we urgently need to change something. If this includes restoring top predators, then we need to think big.

Thomas Newsome, Fulbright Scholar and Postdoctoral Research Fellow, Deakin University

This article was originally published on The Conversation. Read the original article.

Why do some graziers want to retain, not kill, dingoes?

File 20170512 32588 nff9gs
Australia has a complex relationship with the dingo.
Angus Emmott, Author provided

Euan Ritchie, Deakin University

Vast, ancient, nutrient-poor, with wild swings between droughts, floods and fires: this describes much of the Australian continent. Livestock grazing and farming in such a land is certainly not without its challenges. The Conversation

Where we’ve failed to work with the local conditions, we see barren plains, dust storms, the extinction of native species, and the repossession of properties by banks, among many ills.

But such a dire picture is far from universal, and belies the fact that many who live on the land are also among our most innovative land managers. Many projects offer potential benefits for livestock production and the environment alike, but without support progress may be hindered.

Putting dingoes to work

One of the most contentious examples involves encouraging dingoes. Many pastoral areas require land managers to take “all reasonable and practical steps” to manage the risk of dingoes, which are classed as pest animals.

But a growing body of research argues that dingoes can be effective at controlling kangaroo and feral goat populations, especially on cattle stations.

A Western Australian couple, David Pollock and Frances Jones, were recently featured on Australian Story for their decision to regenerate their property, Wooleen, by de-stocking, encouraging local flora and fauna, and investing in ecotourism.

Their neighbours, including sheep graziers whose stock are vulnerable to dingoes, feel this is an irresponsible decision. Graziers have a mandate to control dingoes (“wild dogs”, to many) and dingo-domestic dog hybrids — which can’t be easily and reliably distinguished in the wild.

Dingoes are known to be very effective at controlling kangaroo populations.
Angus Emmott

While the impacts and merits of encouraging dingoes in sheep country are hotly debated, their role in the management of cattle stations is much better understood. But restrictive legislation and the stigma attached to dingoes are frustrating for those who see them as having a vital ecological and economic role for their properties.

Queensland grazier Angus Emmott writes that his beef cattle enterprise, Noonbah station, has benefited from leaving dingoes and kangaroos alone:

We run a beef cattle enterprise in the top end of the Queensland channel country, southwest of Longreach. As a part of our management plan, we leave the dingoes and the ’roos alone. We see a range of benefits to our operation.

When the dingoes don’t have their social structure disrupted by poison baiting, trapping and shooting, only the apex bitch breeds, once a year at most. These family groups have strictly defined ranges, and they kill or chase off other wild dogs or dingoes that intrude. They also keep kangaroos down to very low numbers, which is a huge benefit in regards to pasture growth and being able to rest our paddocks. The dingoes also keep down feral pig, cat and fox numbers.

Yes, dingoes do take some of our calves, but the benefits of pasture growth and feral animal control result in a net benefit of better land condition and a greater dollar return. Dingoes also benefit biodiversity conservation and soil condition. We acknowledge this management model does not work in sheep country, including for some of our nearby neighbours, and in these cases we need to look at different forms of management, such as fencing and/or companion and guardian animals.

Research supports the financial benefits of this approach in certain circumstances. Some studies have found that, perversely, taking lethal action against dingoes can increase the incidence of attacks on stock and boost the population of herbivores that compete with cattle for pasture.

Solutions for protecting livestock against attack, such as guardian dogs, are also at hand and may be considerably cheaper than constructing and maintaining extensive predator-proof fences. Livestock guardian dogs have been shown to be effective in numerous locations across Australia, on large and small grazing properties. But investment from state and federal government (and related agencies) aimed at encouraging such innovation has been lacking.

Kangaroos can become very abundant following rain and without control by dingoes.
Angus Emmott

Working with the land

Regardless of whether graziers take the drastic steps seen at Wooleen, now is the time to reflect on the direction of Australia’s land management.

If we’re to overcome the many challenges we face, including the impacts of climate change on food production, then we need to support the bold new thinking emerging from rural and regional Australia, and our scientific institutions.

Such ideas could include making better use of native animals – better suited to Australian conditions – as sources of meat, and reforming land use legislation to allow new industries.

Seeing some of the worst land degradation first hand it’s easy to think that it’s all too hard and that environmental repair will take decades, if not centuries. This can invite inertia and apathy, the enemies of positive change.

But the stories of Wooleen, Noonbah and other innovators show us what is possible. Science has helped demonstrate ecological repair can happen faster and to a greater extent than many might appreciate.

Big changes certainly carry risks, and these must be managed carefully, but new and sometimes brave ideas will always improve our understanding of the land. Whatever the outcome, such knowledge helps guide better decisions for more sustainable grazing, farming and bio-diverse conservation.

Euan Ritchie would like to acknowledge the contribution of Angus Emmott to this article.

Euan Ritchie, Senior Lecturer in Ecology, Centre for Integrative Ecology, School of Life & Environmental Sciences, Deakin University

This article was originally published on The Conversation. Read the original article.

A wolf in dogs’ clothing? Why dingoes may not be Australian wildlife’s saviours

Helen Morgan, University of New England; Guy Ballard, University of New England, and John Thomas Hunter, University of New England

Dingoes have often been hailed as a solution to Australia’s threatened species crisis, particularly the extreme extinction rate of the country’s small mammals.

But are dingoes really the heroes-in-waiting of Australian conservation? The truth is that no one knows, although our recent research casts a shadow over some foundations of this idea.

The notion of dingoes as protectors of Australian ecosystems was inspired largely by the apparently successful reintroduction of wolves into Yellowstone National Park in the United States. But Australia’s environments are very different.

Cascading species

To understand the recent excitement about wolves, we need to consider an ecological phenomenon known as “trophic cascades”. The term “trophic” essentially refers to food, and thus trophic interactions involve the transfer of energy between organisms when one eats another.

Within ecosystems, there are different trophic levels. Plants are typically near the base; herbivores (animals that eat plants) are nearer the middle; and predators (animals that eat other animals) are at the top.

The theory of trophic cascades describes what happens when something disrupts populations of top-order predators, such as lions in Africa, tigers in Asia, or Yellowstone’s wolves.

The wolves’ decline allowed herbivores, such as elk, to increase. In turn, the growing elk population ate too much of the shrubby vegetation alongside rivers, which, over time, changed from being mostly willow thickets to grassland. Then another herbivore – beavers – that relies on willows went locally extinct. This in turn affected the ecology of the local streams.

Wolves play a key role in Yellowstone’s ecosystems.
Wolf image from

Without beavers to engineer dams, local waterways changed from a series of connected pools to eroded gutters, with huge flow-on effects for smaller aquatic animals and plants.

Now, the reintroduction of wolves appears to have reduced the impact of elk on vegetation, some riparian areas have regenerated, some birds have returned and there are signs of beavers coming back. That said, wolf reintroduction has not yet fully reversed the trophic cascade.

Comparing apples with quandongs

Sturt National Park, in the New South Wales outback, has been nominated as an experimental site for reintroducing dingoes. Recently, we compared the environment of Sturt with Yellowstone to consider how such a reintroduction might play out.

These regions are clearly very different. Both are arid, but that is where the similarity ends. Yellowstone has a stable climate and nutrient-rich soils, sits at high altitude and features diverse landscapes. Precipitation in Yellowstone hasn’t dropped below 200mm per year in more than a century.

Herds of bison in Yellowstone National Park.
Helen Morgan

Yellowstone’s precipitation falls largely as heavy winter snow. Each spring the snowmelt flows in huge volumes into rivers, streams and wetlands across the landscape. This underpins a predictable supply of resources which, in turn, triggers herbivores to migrate and reproduce every year.

These predictable conditions support a wide range of carnivores and herbivores, including some of North America’s last-remaining “megafauna”, such as bison, which can tip the scales at over a tonne. Yellowstone also has many large predators – wolves, grizzly bears, black bears, mountain lion, lynx and coyotes all coexist there – along with a range of smaller predators too.

Predators in Yellowstone can be sure that prey will be available at particular times. The environment promotes stable, strong trophic links, allowing individual animals to reach large sizes. This strong relationship between trophic levels means that when the system is perturbed – for instance, when wolves are removed – trophic cascades can occur.

Unlike Yellowstone, arid Australia is dry, flat, nutrient-poor and characterised by one of the most extreme and unpredictable climates on Earth. The yearly rainfall at Sturt reaches 200mm just 50% of the time.

Australia’s Sturt Desert has a highly unpredictable climate.
Helen Morgan

Australia’s arid ecosystems have evolved largely in isolation for 45 million years. In response to drought, fire and poor soils, arid Australia has evolved highly specialised ecosystems, made up of species that can survive well-documented “boom and bust” cycles.

Unlike the regular rhythm of Yellowstone life, sporadic pulses of water and fire affect and override the trophic interactions of species, between plants and herbivores, and predators and their prey. Our native herbivores travel in response to patchy and unpredictable food sources in boom times. But however good the boom, the bust is certain to follow.

Unpredictable but inevitable drought weakens trophic links between predators, herbivores and plants. Individuals die due to lack of water, populations are reduced and can only recover when rain comes again.

Our arid wildlife is very different from Yellowstone’s too. Our megafauna are long gone. So too are our medium-sized predators, such as thylacines.

Today, arid Australia’s remaining native wildlife is characterised by birds, reptiles and small mammals, along with macropods that are generally much smaller than the herbivores in Yellowstone.

Our predators are small and mostly introduced species, including dingoes, foxes and cats. None is equivalent to wolves, mountain lions or bears, which can reach more than three times the weight of the largest dingo. Wolves are wolves, and dingoes are dogs.

Wolves in dingo clothes?

What does all this mean for Australia? Yellowstone’s stable climate means that there are strong and reliable links between predators, prey and plants. By comparison, arid Australia’s climate is dramatically unstable.

This raises the question of whether we can reasonably expect to see the same sorts of relationships between species, and whether dingoes are likely to help restore Australia’s ecosystems.

We should conduct experiments to understand the roles of dingoes and the impacts of managing them. How we manage predators, including dingoes, should be informed by robust knowledge of local ecosystems, including predators’ roles within them.

What we shouldn’t do is expect that dingoes will necessarily help Australia’s wildlife, based on what wolves have done in snowy America. The underlying ecosystems are very different.

Many people are inspired by the apparently successful example of wolves returning to Yellowstone, but in Australia we should tread carefully.

Rather than trying to prove that dingoes in Australia are just as beneficial as wolves in Yellowstone, we should seek to understand the roles that dingoes really play here, and work from there.

The Conversation

Helen Morgan, Phd candidate, Ecology, University of New England; Guy Ballard, Adjunct Senior Lecturer, University of New England, and John Thomas Hunter, Adjunct Associate Professor in Landscape Ecology, University of New England

This article was originally published on The Conversation. Read the original article.