Category Archives: Media

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

By Tim Doherty (Deakin University), Chris Dickman (University of Sydney), Dale Nimmo (Charles Sturt University), Euan Ritchie (Deakin University) and Thomas Newsome (University of Sydney).

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

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.

Large (at least 7 kg) and medium-sized (0.5 to 6.9 kg) 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 500 g); middle row: reptiles and medium-sized mammals (0.5-6.9kg); bottom row: rabbits and large mammals (at least 7 kg).

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).

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

The Conservation: Guardian dogs, fencing, and ‘fladry’ protect livestock from carnivores

Livestock guardian dog breeds, such as Maremma, are often raised with and trained to consider themselves part of a livestock herd and so protect their herd from threats. Image via Shutterstock.

By Lily van Eeden (University of Sydney), Adrian Treves (University of Wisconsin-Madison), and Euan Ritchie (Deakin University).

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

Farmers have struggled for millennia to protect their livestock from wolves, lions, bears, and other large carnivores. It’s expensive and time-consuming for farmers, governments and related agencies. Many current approaches have led to dramatic reductions or the complete loss of some apex predators from many regions of the globe.

Despite these substantial costs and their long history, we have remarkably little understanding of what methods best reduce livestock attacks.

A recent synthesis study, led by Lily van Eeden, Ann Eklund, Jennie Miller, and Adrian Treves with a total of 21 authors from 10 countries, found that there’s a worldwide dearth of rigorous experimental studies testing the effectiveness of interventions to protect livestock from carnivores.

Where studies do exist, results were mixed. Some management interventions did reduce livestock losses, some made little to no difference, and some resulted in increased livestock losses. This means that for some methods, farmers would be better off doing nothing at all than using them.

Poor evidence, poor outcomes

The scant evidence is cause for concern. Aside from financial waste, preventable livestock attacks cause economic, emotional, and social costs for farmers. And both livestock and carnivores may be left maimed and suffering by human failures to separate the two sets of animals.

Too often, studies and management programs measure success based on money spent or saved, numbers of community members who contributed, or carnivores killed. None of these factors necessarily mean livestock loss is prevented or reduced.

In fact, livestock owners, policy makers, and scientists should work together to build an evidence base and discover what works best to reduce attacks on livestock under different conditions.

What works and why

Where we found rigorous studies quantifying livestock loss, three methods were consistently effective: livestock guardian dogs, some kinds of fencing, and a deterrent called “fladry” (a Polish word for strips of cloth or plastic flagging hung at regular intervals along a rope or fence line).

Livestock guardian dogs have been used successfully in Europe for centuries and are now seeing a revival elsewhere, including in North America and Africa.

Livestock guardian dog breeds, such as Maremma and Komondor, are typically much larger than herding dogs. They are raised with and trained to consider themselves part of a livestock herd and so protect their herd from threats.

While dogs are most common, they’re not the only guardian animals: llamas, alpacas, and donkeys are also used to protect livestock from smaller predators like coyotes and foxes, but more research is needed to determine how effective they are.

Fencing can be simple post-and-wire, an electric fence, or corrals, kraals or bomas (circular enclosures used in some parts of Africa) constructed from stones or wood.

Livestock can be kept within fenced areas all the time, or only at night when they are most vulnerable to carnivores (who often hunt at night, dawn, or dusk).

Our study didn’t find sufficient evidence to show that all kinds of fencing work, but there was enough that they should be considered generally effective and adapted to local conditions.

“Fladry” is a Polish word for strips of cloth or plastic flagging hung at regular intervals along a rope or fence line. Fladry is usually red, which is considered the most effective colour for scaring away carnivores. This method has been proven effective at deterring predators like grey wolves and coyotes from entering pastures.

Interestingly, all three of the methods we found to be generally effective do not involve killing carnivores.

This is good news for carnivore conservation, because it means that management can simultaneously protect livestock and carnivores. Large carnivores can play crucial roles in ecosystem regulation, so removing them can cause cascading consequences for landscapes and biodiversity.

Given the damage that ineffective management can cause to farming communities, animal welfare, and ecosystems, we hope our research serves as a catalyst for policy-makers and practitioners to think critically about the methods they use and why.

Too often, we continue to use a particular method due to habit and history, but that doesn’t mean it’s the best way to protect assets.

Governments that continue to fund and encourage ineffective management are not giving farming communities the best chance of success.

The Conversation

YouTube: Carnivore conservation needs evidence-based livestock protection

A new study published in the peer-reviewed journal PLOS Biology reveals certain nonlethal methods are effective for managing predators in agricultural landscapes. Twenty-one authors from 10 nations reviewed 114 peer-reviewed scientific studies measuring the effectiveness of lethal and non-lethal methods for reducing carnivore predation on livestock. Livestock guardian dogs, livestock enclosures and fladry all were scientifically shown to be effective conflict deterrents.

 

Australian Geographic: The extinction crisis: Australians call for a radical re-haul of environmental laws

Australia is failing to meet international obligations to protect our unique wildlife, experts say.

Recounting a list of Australian animals on the brink of extinction comes all too easily to Euan Ritchie, an Associate Professor in Wildlife Ecology and Conservation at Deakin University.

“Obvious examples include the orange-bellied parrot, which only has a few individuals left in the wild,” he says, referring to the multi-coloured grass parrot with a total population of less than 50 that migrates between Tasmania and mainland Australia…

Continue reading on the Australian Geographic website

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

Western Australian Minister for the Environment Stephen Dawson has declared that the dingo, Australia’s native canine, will no longer be classified as native. Image credit Leo via Flickr.

By Bradley Smith (CQUniversity Australia), Euan Ritchie (Deakin University) and Lily van Eeden, (University of Sydney).

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

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.

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.

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.

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

ABC News: Dingoes to remain classified as non-native wild dogs under reform to Western Australian law

Widespread reforms to WA’s Biodiversity Conservation Act, expected next year, will not consider a change to the existing classification of a dingo as a wild dog, not native to Australia.

The iconic animals are considered no different to wild dogs and can be trapped or killed without permission in many places.

Dingoes are currently classed as unprotected native fauna and a declared pest, but the animals will be listed as non-fauna under widespread reform to the Act…

Continue reading on the ABC News website

Passing the brumby bill is a backward step for environmental protection in Australia

With the passing of the so-called “brumby bill” against scientific advice, feral horses will continue to damage the internationally significant Kosciuszko National Park.

By Don Driscoll, Euan Ritchie, and Tim Doherty (Deakin University)

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

Late on Wednesday night the so-called “brumby bill” was passed without amendment in the New South Wales Parliament. The controversial Coalition bill, supported by the Christian Democrats and the Shooters, Fishers and Farmers Party, means that feral horses must be kept in Kosciuszko National Park.

It also creates a community advisory panel, with no scientific experts appointed, to advise the minister on how to manage the horse population in the alpine ecosystem.

The NSW government has attracted accusations of a conflict of interest. Former Nationals member Peter Cochran, who now runs a commercial venture offering brumbie-spotting rides through the National Park (and who has donated extensively to Deputy Premier John Barilaro) reportedly commissioned lawyers to draft the bill. Peter Cochran, John Barilaro and Gladys Berejiklian have denied all accusations of conflict of interest and underhanded conduct.

The bill has also been criticised by scientific bodies. In a letter to NSW Premier Gladys Berejiklian this week, the Australian Academy of Science noted that the legislation removes consideration of scientific advice, and called for the bill to be withdrawn or substantially amended.

In a rare move, the International Union for the Conservation of Nature has also written to the NSW government, expressing concern over the potential degradation of this internationally significant national park.

Out of step with other states

The NSW Labor Party does not support the bill and has pledged to repeal the legislation if elected next March. The legislation represents a radical change in NSW’s management of feral horses, coming after a 2016 draft strategy that recommenced reducing their population by 90% over 20 years.

NSW now stands in contrast to other Australian states. Last Saturday, Victoria launched its Feral Horse Strategic Action Plan. That plan aims to protect native species and ecosystems in national parks by removing or controlling feral horses and is a welcome step in the right direction. Victorian environment minister Lily D’Ambrosio called on the NSW and federal governments to support a unified approach to feral horse management in Australia’s alpine regions.

Is culling in or out?

The Victorian plan excludes aerial culling but will revisit horse control methods if the proposed trapping methods don’t reduce environmental impacts. Aerial culling is widely practised throughout Australia, including Western Australia, the Northern Territory, Queensland (where culling was used to improve road safety), and the Australian Capital Territory, which borders Kosciuszko National Park.

Barilaro argued against aerial culling when he presented the Brumby bill to parliament, calling it cruel and barbaric. He reiterated that the bill is meant to prevent lethal control in his response to Victoria’s announcement. But surprisingly, the draft legislation makes no mention of control methods, lethal or otherwise.

The deputy premier also referred to the Guy Fawkes National Park horse cull in northern NSW in 2000 to support his argument against aerial culling. But an independent enquiry found that the cull was an appropriate humane response to the situation, where horses were starving to death and causing environmental damage after a fire. The RSPCA and independent reports show that aerial culling is an acceptable and humane way to manage horse numbers.

Further, the brumby bill now locks in the predictable outcome that thousands of horses are likely to starve to death in the next drought or after large fires. It is therefore puzzling that actions likely to increase horse suffering are not of great concern to many within the pro-brumby lobby.

Greater emphasis, instead, has been put on a cultural argument for protecting feral horses: for example, by claiming that feral horses made enormous contributions to Australia’s World War One effort. However, the cultural heritage report prepared for the NSW National Parks Service says “there is no definitive evidence that remount horses were directly taken from the brumby population of what is now Kosciusko National Park”.

The Sydney Olympics opening ceremony was also offered as evidence that brumbies are integral to Australian culture. However, Australian Stock horses, not brumbies, were showcased at the Sydney Olympics – a distinct breed, established by horse enthusiasts in the 1970s.

That said, it is true that horses in the snowy mountains do have local cultural value. But so too does the native fauna and flora threatened by feral horses, many of which only occur in Australia’s high country. This includes species such as the southern corroboree frog, alpine she-oak skink, broad-toothed rat, Raleigh sedge and mauve burr-daisy.

Can we compromise?

Is a compromise possible, in which both cultural and conservation goals can be accommodated? We think so. The feral horse population can be removed from the national parks and sensitive ecosystems. Brumby herds can thrive on extensive private property in the region, an approach already proven in South Australia’s Coffin Bay National Park.

The brumby bill was written and presented to parliament by groups with at best a perceived conflict of interest, and promoted by using inaccurate information about culling and heritage. It has been roundly criticised by leading national and international scientific bodies for not taking adequate account of science and the key role of national parks in conserving biodiversity.

That this bill has now passed the NSW upper house is a further backward step for conservation goals and Australia’s international reputation for environmental protection, and sets a dangerous precedent by undermining prominent national and state environmental policy. It remains to be seen how this legislation aligns with the federal Environment Protection and Biodiversity Conservation Act, given that it literally tramples over several matters of national environmental significance.

The Conversation