Cats wreak havoc on native wildlife, but we’ve found one adorable species outsmarting them



Zoos Victoria, Author provided

Euan Ritchie, Deakin University; Amy Coetsee, University of Melbourne; Anthony Rendall, Deakin University; Tim Doherty, University of Sydney, and Vivianna Miritis, University of Sydney

Feral and pet cats are responsible for a huge part of Australia’s shameful mammal extinction record. Small and medium-sized ground-dwelling mammals are most susceptible.

But we’ve found one mammal in particular that can outsmart cats and live alongside them: the long-nosed potoroo.




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These miniature kangaroo-like marsupials are officially listed as vulnerable. And after the recent devastating fires, extensive swathes of their habitat in southeastern Australia were severely burnt, leaving them more exposed to predators such as foxes and cats. But the true extent of the impact on their numbers remains unclear.

Amid the devastation, our new study is reason to be optimistic.

Long-nosed potoroos are a bit like mini kangaroos, but spend much of their time digging for fungi.
Zoos Victoria

Using motion-sensing camera traps on the wildlife haven of French Island – which is free of foxes, but not cats – we found potoroos may have developed strategies to avoid prowling cats, such as hiding in dense vegetation.

If these long-nosed potoroos can co-exist with one of the world’s most deadly predators, then it’s time we rethink our conservation strategies.

Surviving cats with a deadly game of hide and seek

We conservatively estimated that between five and 14 cats lived in our study area (but it takes only one cat to eradicate a population of native animals).

Although cats were common here, we detected them less often in areas of dense vegetation. By contrast, this was where we found potoroos more often.

French Island’s thick vegetation provides potoroos with critical refuge to evade feral cats.
Vivianna Miritis

Long-nosed potoroos are nocturnal foragers that mainly, but not exclusively, feed in more open habitat before sheltering in dense vegetation during the day. But we found potoroos rarely ventured out of their thick vegetation shelter.

This may be because they’re trading off potentially higher quality foraging habitat in more open areas against higher predation risk. In other words, it appears they’ve effectively learnt to hide from the cats.




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Another intriguing result from our study was that although potoroos and feral cats shared more than half of their activity time, the times of peak activity for each species differed.

Cats were active earlier in the night, while potoroo activity peaked three to four hours later. This might be another potoroo strategy to avoid becoming a cat’s evening meal.

Temporal activity of cats and long-nosed potoroos for winter and summer, on French Island, Victoria. Their overlap is represented by the area shaded in grey. Modified from Miritis et al. (2020).

Still, completely avoiding cats isn’t possible. Our study site was in the national park on French Island, and it’s likely cats saturate this remnant patch of long-nosed potoroo habitat.

It’s also possible cats may be actively searching for potoroos as prey, and indeed some of our camera images showed cats carrying young long-nosed potoroos in their mouths. These potoroos were more likely killed by these cats, rather than scavenged.

Cats are expert hunters

Cats are exceedingly difficult to manage effectively. They’re adaptable, elusive and have a preference for live prey.

The two most common management practices for feral cats are lethal control and exclusion fencing. Lethal control needs to be intensive and conducted over large areas to benefit threatened species.




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And outside of predator-free sanctuaries, it must be ongoing. If control stops, cats can reinvade from surrounding areas.

Safe havens” – created through the use of exclusion fencing or predator-free islands – can overcome some of these challenges. But while exclusion fencing is highly effective, it can create other bad outcomes, including an over-abundance of herbivores, leading to excessive grazing of vegetation.

Camera traps can tell us a lot about how introduced predators and native wildlife interact.
Zoos Victoria and Deakin University

Fencing and islands can result in native animals rapidly losing their anti-predator behaviour. This can limit the success of reintroducing them to areas outside predator-free havens.

In any case, removing introduced predators might not be really necessary in places native species can co-exist. If long-nosed potoroos have learnt to live with feral cats, we should instead focus on how to maintain their survival strategies.

Why cat eradication isn’t always the best option

It’s clear cats are here to stay, so we shouldn’t simply fall back largely on predator eradication or predator-free havens as the only way to ensure our wildlife have a fighting chance at long-term survival.

Yes, for some species, it’s vital to keep feral predators away. But for others like long-nosed potoroos, conserving and creating suitable habitat and different vegetation densities may be the best way to keep them alive.




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But perhaps most important is having predator-savvy insurance populations, such as long-nosed potoroos on French Island. This is incredibly valuable for one day moving them to other areas where predators – native or feral – are present, such as nearby Phillip Island.

In the absence of predators, native wildlife can rapidly lose their ability to recognise predator danger. Programs aimed at eradicating introduced predators where they’re co-existing with native species need to pay careful attention to this.The Conversation

Euan Ritchie, Associate Professor in Wildlife Ecology and Conservation, Centre for Integrative Ecology, School of Life & Environmental Sciences, Deakin University; Amy Coetsee, Threatened Species Biologist, University of Melbourne; Anthony Rendall, Associate Lecturer in Conservation Biology, Deakin University; Tim Doherty, ARC DECRA Fellow, University of Sydney, and Vivianna Miritis, PhD Candidate, University of Sydney

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

Turn off the porch light: 6 easy ways to stop light pollution from harming our wildlife



Shutterstock

Emily Fobert, Flinders University; Katherine Dafforn, Macquarie University, and Mariana Mayer-Pinto, UNSW

As winter approaches, marine turtle nesting in the far north of Australia will peak. When these baby turtles hatch at night, they crawl from the sand to the sea, using the relative brightness of the horizon and the natural slope of the beach as their guide.

But when artificial lights outshine the moon and the sea, these hatchlings become disorientated. This leaves them vulnerable to predators, exhaustion and even traffic if they head in the wrong direction.




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Baby turtles are one small part of the larger, often overlooked, story of how light pollution harms wildlife across the land and underwater.

Green Turtle’s Battle For Survival | Planet Earth | BBC Earth.

Today, more than 80% of people – and 99% of North American and European human populations – live under light-polluted skies. We have transformed the night-time environment over substantial portions of the Earth’s surface in a very short time, relative to evolutionary timescales. Most wildlife hasn’t had time to adjust.

In January, Australia released the National Light Pollution Guidelines for Wildlife. These guidelines provide a framework for assessing and managing the impacts of artificial light.

The guidelines also identify practical solutions that can be used globally to manage light pollution, both by managers and practitioners, and by anyone in control of a light switch.




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The guidelines outline six easy steps anyone can follow to minimise light pollution without compromising our own safety.

Although light pollution is a global problem and true darkness is hard to come by, we can all do our part to reduce its impacts on wildlife by changing how we use and think about light at night.

Light pollution can interfere with clownfish reproductive cycle.
Shutterstock

1. Start with natural darkness. Only add light for a specific purpose

Natural darkness should be the default at night. Artificial light should only be used if it’s needed for a specific purpose, and it should only be turned on for the necessary period of time.

This means it’s okay to have your veranda light on to help you find your keys, but the light doesn’t need to stay on all night.

Similarly, indoor lighting can also contribute to light pollution, so turning lights off in empty office buildings at night, or in your home before you go to sleep, is also important.

2. Use smart lighting controls

Advances in smart control technology make it easy to manage how much light you use, and adaptive controls make meeting the goals of Step 1 more feasible.

Investing in smart controls and LED technology means you can remotely manage your lights, set timers or dimmers, activate motion sensor lighting, and even control the colour of the light emitted.

These smart controls should be used to activate artificial light at night only when needed, and to minimise light when not needed.

3. Keep lights close to the ground, directed and shielded

Any light that spills outside the specific area intended to be lit is unnecessary light.

Light spilling upward contributes directly to artificial sky glow – the glow you see over urban areas from cumulative sources of light. Both sky glow and light spilling into adjacent areas on the ground can disrupt wildlife.

Installing light shields allow you to direct the light downward, which significantly reduces sky glow, and to direct the light towards the specific target area. Light shields are recommended for any outdoor lighting installations.

Step 3: Keep lights close to ground (a) and use shields to light only the intended area (b)
National Light Pollution Guidelines for Wildlife Including Marine Turtles, Seabirds and Migratory Shorebirds, Commonwealth of Australia 2020

4. Use the lowest intensity lighting

When deciding how much light you need, consider the intensity of the light produced (lumens), rather than the energy required to make it (watts).

LEDs, for example, are often considered an “environmentally friendly” option because they’re relatively energy efficient. But because of their energy efficiency, LEDs produce between two and five times as much light as incandescent bulbs for the same amount of energy consumption.




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So, while LED lights save energy, the increased intensity of the light can lead to greater impacts on wildlife, if not managed properly.

5. Use non-reflective, dark-coloured surfaces.

Sky glow has been shown to mask lunar light rhythms of wildlife, interfering with the celestial navigation and migration of birds and insects.

Highly polished, shiny, or light-coloured surfaces – such as structures painted white, or polished marble – are good at reflecting light and so contribute more to sky glow than darker, non-reflective surfaces.

Choosing darker coloured paint or materials for outdoor features will help reduce your contribution to light pollution.

6. Use lights with reduced or filtered blue, violet and ultra-violet wavelengths

Wavelength perception in wildlife – most animals are sensitive to short-wavelength (blue/violet) light.
National Light Pollution Guidelines for Wildlife Including Marine Turtles, Seabirds and Migratory Shorebirds, Commonwealth of Australia 2020

Most animals are sensitive to short-wavelength light, which creates blue and violet colours. These short wavelengths are known to suppress melatonin production, which is known to disrupt sleep and interfere with circadian rhythms of many animals, including humans.

Choosing lighting options with little or no short wavelength (400-500 nanometres) violet or blue light will help to avoid unintended harmful effects on wildlife.

For example, compact fluorescent and LED lights have a high amount of short wavelength light, compared low or high-pressure sodium, metal halide, and halogen light sources.




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The Conversation


Emily Fobert, Research Associate, Flinders University; Katherine Dafforn, Senior Lecturer in Environmental Sciences, Macquarie University, and Mariana Mayer-Pinto, Senior Research Associate in marine ecology, UNSW

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

After the bushfires, we helped choose the animals and plants in most need. Here’s how we did it



Daniel Marius/AAP

John Woinarski, Charles Darwin University; Dale Nimmo, Charles Sturt University; Rachael Gallagher, Macquarie University, and Sarah Legge, Australian National University

No other event in our lifetimes has brought such sudden, drastic loss to Australia’s biodiversity as the last bushfire season. Governments, researchers and conservationists have committed to the long road to recovery. But in those vast burnt landscapes, where do we start?

We are among the wildlife experts advising the federal government on bushfire recovery. Our role is to help determine the actions needed to stave off extinctions and help nature recover in the months and years ahead.

Our first step was to systematically determine which plant and animal species and ecosystems needed help most urgently. So let’s take a closer look at how we went about it.

Plants and animals are recovering from the fires, but some need a helping hand.
David Crosling/AAP

Sorting through the smoke

One way to work out how badly a species is affected by fire is to look at how much of its distribution – or the area in which it lives – was burnt.

This is done by overlapping fire maps with maps or records showing the species’ range. The greater the overlap, the higher the potential fire impact. But there are several complicating factors to consider:

1. Susceptibility: Species vary in how susceptible they are to fire. For instance, animals that move quickly – such as red-necked wallabies and the white-throated needletail – can escape an approaching fire. So too can animals that burrow deeply into the ground, such as wombats.

Less mobile animals, or those that live in vegetation, are more likely to die. We also considered post-fire recovery factors such as a species’ vulnerability to predators and reproductive rate.

The white-throated needle tail can escape the flames.
Tom Tarrant/Flickr

2. What we know: The quality of data on where species occur is patchy. For example, there are thousands of records for most of Australia’s 830 or so bird species. But there are very few reliable records for many of Australia’s 25,000-odd plant species and 320,000-odd invertebrate species.

So while we can estimate with some confidence how much of a crimson rosella’s distribution burned, the fire overlaps for less well-known species are much less certain.

3. The history of threats: The impact of fires on a region depends on the extent of other threats, such as drought and the region’s fire history. The time that elapses between fires can influence whether populations have recovered since the last fire.

For instance, some plants reproduce only from seed rather than resprouting. Fires in quick succession can kill regrowing plants before they’ve matured enough to produce seed. If that happens, species can become locally extinct.


Authors supplied

4. Fire severity: Some areas burn more intensely than others. High severity fires tend to kill more animals. They also incinerate vegetation and can scorch seeds lying in the soil.

Many Australian plant species are exquisitely adapted to regenerate and resprout after fire. But if a fire is intense enough, even these plants may not bounce back.

5. Already threatened?: Many species affected by these bushfires were already in trouble. For some, other threats had already diminished their numbers. Others were highly vulnerable because they were found only in very limited areas.

The bushfires brought many already threatened species closer to extinction. And other species previously considered secure are now threatened.




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Which species made the list?

With these issues in mind, and with contributions from many other experts, we compiled lists of plant, invertebrate and vertebrate species worst-affected by the 2019-20 fires. A similar assessment was undertaken for threatened ecosystems.

Some 471 plant, 213 invertebrate and 92 vertebrate species have been identified as a priority for interventions. Most had more than half their distribution burnt. Many have had more than 80% affected; some had 100% burnt.

The purple copper butterfly is listed as a priority for recovery efforts.
NSW Department of Planning, Industry and Environment

Priority invertebrates include land snails, freshwater crayfish, spiders, millipedes, beetles, dragonflies, grasshoppers, butterflies and bees. Many species had very small ranges.

For example, the inelegantly named Banksia montana mealybug – a tiny insect – existed only in the foliage of a few individuals of a single plant species in Western Australia’s Stirling Range, all of which were consumed by the recent fires.

Some priority plants, such as the Monga waratah, have persisted in Australia since their evolution prior to the break-up of the Gondwanan supercontinent about 140 million years ago. More than 50% of its current range burned, much at high severity. During recovery it is vulnerable to diseases such as phytophthora root rot.




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Some priority vertebrates have tiny distributions, such as the Mt Kaputar rock skink that lives only on rocky outcrops of Mt Kaputar near Narrabri, New South Wales. Others had large distributions that were extensively burnt, such as the yellow-bellied glider.

The priority lists include iconic species such as the koala, and species largely unknown to the public, such as the stocky galaxias, a fish that lives only in an alpine stream near Cooma in NSW.

Half the Monga waratah’s range burned in the fires.
Wikimedia

What’s being done

A federal government scheme is now allocating grants to projects that aim to help these species and ecosystems recover.

Affected species need immediate and longer-term actions to help them avoid extinction and recover. Critical actions common to all fire-affected species are:

  1. careful management of burnt areas so their recovery isn’t compromised by compounding pressures

  2. protecting unburnt areas from further fire and other threats, so they can support population recovery

  3. rapid surveys to identify where populations have survived. This is also the first step in ongoing monitoring to track recovery and the response to interventions.

Targeted control of feral predators, herbivores and weeds is also essential to the recovery of many priority species.

In some rare cases, plants or animals may need to be moved to areas where populations were reduced or wiped out. Captive breeding or seed collection can support this. Such restocking doesn’t just help recovery, it also spreads the risk of population loss in case of future fires.

Feral animals such as cats threaten native species in their recovery.
Hugh McGregor, Threatened Species Recovery Hub

Long road back

The COVID-19 pandemic has led to some challenges in implementing recovery actions. Like all of us, state agency staff, NGOs, academics and volunteer groups must abide by public health orders, which have in some cases limited what can be done and where.

But the restrictions may also have an upside. For instance, fewer vehicles on the roads might reduce roadkill of recovering wildlife.

As states ease restrictions, more groups will be able to continue the recovery process.




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As well as action on the ground, much planning and policy response is still required. Many fire-affected species must be added to threatened species lists to ensure they’re legally protected, and so remain the focus of conservation effort.

Fire management methods must be reviewed to reduce the chance of future catastrophic fires, and to make sure the protection of biodiversity assets is considered in fire management planning and suppression.

Last bushfire season inflicted deep wounds on our biodiversity. We need to deal with that injury. We must also learn from it, so we can respond swiftly and effectively to future ecological disasters.


Many species experts and state/territory agency representatives contributed to the analyses of priority species. Staff from the Department of Agriculture, Water and the Environment (especially the Environmental Resources Information Network (Geospatial and Information Analytics Branch), the Protected Species and Communities Branch and the Threatened Species Commissioner’s Office) and Expert Panel members also contributed significantly to this work.The Conversation

John Woinarski, Professor (conservation biology), Charles Darwin University; Dale Nimmo, Associate Professor in Ecology, Charles Sturt University; Rachael Gallagher, Senior Lecturer/ARC DECRA Fellow, Macquarie University, and Sarah Legge, Professor, Australian National University

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

One cat, one year, 110 native animals: lock up your pet, it’s a killing machine


Anton Darius/Unsplash, CC BY

Jaana Dielenberg, The University of Queensland; Brett Murphy, Charles Darwin University; Chris Dickman, University of Sydney; John Woinarski, Charles Darwin University; Leigh-Ann Woolley, Charles Darwin University; Mike Calver, Murdoch University, and Sarah Legge, Australian National University

We know feral cats are an enormous problem for wildlife – across Australia, feral cats collectively kill more than three billion animals per year.

Cats have played a leading role in most of Australia’s 34 mammal extinctions since 1788, and are a big reason populations of at least 123 other threatened native species are dropping.




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But pet cats are wreaking havoc too. Our new analysis compiles the results of 66 different studies on pet cats to gauge the impact of Australia’s pet cat population on the country’s wildlife.

The results are staggering. On average, each roaming pet cat kills 186 reptiles, birds and mammals per year, most of them native to Australia. Collectively, that’s 4,440 to 8,100 animals per square kilometre per year for the area inhabited by pet cats.

More than one-quarter of Aussie households have pet cats.
Jaana Dielenberg, Author provided

If you own a cat and want to protect wildlife, you should keep it inside. In Australia, 1.1 million pet cats are contained 24 hours a day by responsible pet owners. The remaining 2.7 million pet cats – 71% of all pet cats – are able to roam and hunt.

What’s more, your pet cat could be getting out without you knowing. A radio tracking study in Adelaide found that of the 177 cats whom owners believed were inside at night, 69 cats (39%) were sneaking out for nocturnal adventures.

Surely not my cat

Just over one-quarter of Australian households (27%) have pet cats, and about half of cat-owning households have two or more cats.

Many owners believe their animals don’t hunt because they never come across evidence of killed animals.

But studies that used cat video tracking collars or scat analysis (checking what’s in the cat’s poo) have established many pet cats kill animals without bringing them home. On average, pet cats bring home only 15% of their prey.


Wes Mountain/The Conversation, CC BY-ND

Collectively, roaming pet cats kill 390 million animals per year in Australia.

This huge number may lead some pet owners to think the contribution of their own cat wouldn’t make much difference. However, we found even single pet cats have driven declines and complete losses of populations of some native animal species in their area.

Documented cases have included: a feather-tailed glider population in south eastern NSW; a skink population in a Perth suburb; and an olive legless lizard population in Canberra.

Urban cats

On average, an individual feral cat in the bush kills 748 reptiles, birds and mammals a year – four times the toll of a hunting pet cat. But feral cats and pet cats roam over very different areas.

Pet cats are confined to cities and towns, where you’ll find 40 to 70 roaming cats per square kilometre. In the bush there’s only one feral cat for every three to four square kilometres.

So while each pet cat kills fewer animals than a feral cat, their high urban density means the toll is still very high. Per square kilometre per year, pet cats kill 30-50 times more animals than feral cats in the bush.

The impact of roaming pet cats on Australian wildlife.

Most of us want to see native wildlife around towns and cities. But such a vision is being compromised by this extraordinary level of predation, especially as the human population grows and our cities expand.

Many native animals don’t have high reproductive rates so they cannot survive this level of predation. The stakes are especially high for threatened wildlife in urban areas.

Pet cats living near areas with nature also hunt more, reducing the value of places that should be safe havens for wildlife.




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The 186 animals each pet cat kills per year on average is made up of 110 native animals (40 reptiles, 38 birds and 32 mammals).

For example, the critically endangered western ringtail possum is found in suburban areas of Mandurah, Bunbury, Busselton and Albany. The possum did not move into these areas – rather, we moved into their habitat.

What can pet owners do?

Keeping your cat securely contained 24 hours a day is the only way to prevent it from killing wildlife.

It’s a myth that a good diet or feeding a cat more meat will prevent hunting: even cats that aren’t hungry will hunt.

A bell on a cat’s collar doesn’t stop hunting, it only makes hunting a little harder.
Wes Mountain/The Conversation, CC BY-ND

Various devices, such as bells on collars, are commercially marketed with the promise of preventing hunting. While some of these items may reduce the rate of successful kills, they don’t prevent hunting altogether.

And they don’t prevent cats from disturbing wildlife. When cats prowl and hunt in an area, wildlife have to spend more time hiding or escaping. This reduces the time spent feeding themselves or their young, or resting.

In Mandurah, WA, the disturbance and hunting of just one pet cat and one stray cat caused the total breeding failure of a colony of more than 100 pairs of fairy terns.

Benefits of a life indoors

Keeping cats indoors protects pet cats from injury, avoids nuisance behaviour and prevents unwanted breeding.

Cats allowed outside often get into fights with other cats, even when they’re not the fighting type (they can be attacked by other cats when running away).

Two cats in Western Australia stopped fairy terns from breeding.
Shutterstock

Roaming cats are also very prone to getting hit by a vehicle. According to the Humane Society of the United States, indoor cats live up to four times longer than those allowed to roam freely.

Indoor cats have lower rates of cat-borne diseases, some of which can infect humans. For example, in humans the cat-borne disease toxoplasmosis can cause illness, miscarriages and birth defects.




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For whom the bell tolls: cats kill more than a million Australian birds every day


But Australia is in a very good position to make change. Compared to many other countries, the Australian public are more aware of how cats threaten native wildlife and more supportive of actions to reduce those impacts.

It won’t be easy. But since more than one million pet cats are already being contained, reducing the impacts from pet cats is clearly possible if we take responsibility for them.The Conversation

Jaana Dielenberg, Science Communication Manager, The University of Queensland; Brett Murphy, Associate Professor / ARC Future Fellow, Charles Darwin University; Chris Dickman, Professor in Terrestrial Ecology, University of Sydney; John Woinarski, Professor (conservation biology), Charles Darwin University; Leigh-Ann Woolley, Adjunct Research Associate, Charles Darwin University; Mike Calver, Associate Professor in Biological Sciences, Murdoch University, and Sarah Legge, Professor, Australian National University

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

National parks are for native wildlife, not feral horses: federal court




Don Driscoll, Deakin University and Dick Williams, Charles Darwin University

Today, the federal court ruled feral horses can be removed from the Victorian high country.

The case was brought by the Australian Brumby Alliance against the Victorian Government in 2018. Since then, the strategic management plan for feral horses has been shelved, allowing feral horse numbers to increase without control.

In the northern area of Kosciuszko National Park numbers jumped from an estimated 3,255 in 2014 to 15,687 in 2019, in the absence of any management.




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Double trouble as feral horse numbers gallop past 25,000 in the Australian Alps


Expanding numbers of feral horses roaming the Australian Alps – which are listed as a national heritage site – threaten the alp’s ecosystems, soils and unique species. More feral horses is also an animal welfare issue, as horses face starvation during droughts and have been hit by cars in Kosciuszko.

Feral horses cause extensive damage to fragile ecosystems.
Shutterstock

The ruling is a victory for national parks, which can once again be managed to protect native Australian ecosystems and species. But it stands in stark contrast to the NSW government’s controversial legal protection of feral horses.

Taken to court

The Victorian Government’s strategic action plan, released in 2017, was to remove all horses from the Bogong High Plains, where around 100 horses caused cumulative damage to sensitive alpine ecosystems.

The plan also aimed to trap horses in the eastern Victorian alps, but at a rate so low it was unlikely to make a dent in horse numbers.

Not satisfied with retaining thousands of horses in the eastern alps, in 2018, the Australian Brumby Alliance took out a court injunction to stop horse removal from the Bogong High Plains and prevent substantial reduction in horse numbers in the eastern alps.

High stakes

Twenty-five thousand feral horses in Australia’s alpine parks have damaged peat wetlands listed as threatened under federal and state legislation. Recovery will take decades to centuries.

Feral horses have also eliminated multiple populations of the native broad toothed rat and are a threat to other native species like the corroboree frog and mountain pygmy possum.

And habitat degradation and loss caused by feral horses is officially listed as a threatening process in Victoria and NSW.

Feral horse damage to a swampy area as they trample over important wetlands.
Meg McKone, Author provided

If the court had ruled in favour of the Australian Brumby Alliance’s case, it would have locked in escalating threats to the environment, including threatening already endangered species such as the alpine she-oak skink.

It would also have given at least informal legitimacy to NSW legislation that protects feral horses in Kosciuszko National Park.




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And possibly most damaging, it could have emboldened claims by brumby groups that feral horses should take priority over conservation in other contentious horse hotspots, such as Barmah, Oxley Wild Rivers, Blue Mountains, Guy Fawkes and Barrington Tops National Parks.

Feral horses have eliminated broad toothed mouse populations in the Alps.
Ken Green, Author provided

A matter of cultural heritage

The Australian Brumby Alliance argued removing horses from the alps would compromise its heritage value. They claimed feral horses are part of that heritage, including part of the mountain vistas, the pioneering heritage and myths and legends such as the Man from Snowy River.

The counterpoint from Parks Victoria was that it’s possible to remove horses from the alps while protecting the area’s cultural heritage.

It would be like taking cattle out of the high country, but nevertheless recognising pioneering exploits by preserving cattlemen’s huts.

These high plains will now be protected from feral horses.
Don Driscoll, Author provided

So what did Judge O’Bryan make of this? In a nutshell, the Australian Brumby Alliance did not have a legal hoof to stand on.

He rejected the Australian Brumby Alliance’s argument the Bogong High Plains horse population was likely to be genetically different from other feral horse populations in a way relevant to the case, and rejected claims feral horses could be beneficial to alpine ecosystems.

Judge O’Bryan also rejected the contention that the brumbies are part of the National Heritage values of the Australian Alps and accepted the evidence that feral horses cause substantial environmental damage.

The ruling acknowledged Parks Victoria’s strategic plan to control feral horses was consistent with legal obligations under the Convention on Biological Diversity, the federal EPBC (Environment Protection and Biodiversity Conservation) Act and the state’s Flora and Fauna Guarantee Act.

National parks for nature

Laws and the management of protected areas that reduce their integrity are a global concern. A 2017 study found one-third of Australia’s protected areas had been downgraded, reduced in size or had protection removed to make way for tourism ventures and other developments, like Snowy 2.0 in Kosciuszko National Park.

Kosciusko has faced the brunt of recent downgrading, notably where the NSW government voted to legally protect feral horses in 2018.

This unilateral decision has caused substantial concern for Victoria and the ACT as they face ongoing risks of feral horse incursions from NSW into their own protected areas.

The Australian Brumby Alliance’s court case threatened similar downgrading for Victoria’s alpine parks. However, state, federal and international laws, that place obligations on Australian governments to conserve native species and ecosystems in protected areas, have helped restore sensible park management.

Protecting natural heritage

Toyay’s federal court ruling upholds the right of state agencies to carry out their legal obligations. And it meets the general expectations of Australian society that our national parks exist to conserve native Australian ecosystems and species, particularly as extinction rates in Australia continue at unprecedented rates.




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Feral cat cull: why the 2 million target is on scientifically shaky ground


It also reflects the intent of nature conservation laws. National parks are for conserving our natural heritage, the product of millions of years of evolution on this continent.

Brumby advocates concerned about recent European heritage in Australia can protect horses outside of national parks, an approach pioneered successfully in South Australia.The Conversation

Don Driscoll, Professor in Terrestrial Ecology, Deakin University and Dick Williams, Adjunct Professorial Fellow, Research Institute for the Environment and Livelihoods, Charles Darwin University

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

Most laws ignore ‘human-wildlife conflict’. This makes us vulnerable to pandemics



Shutterstock

Katie Woolaston, Queensland University of Technology

Never before have we seen how the human use of wildlife can yield such catastrophe, as we have with COVID-19.

The current available evidence indicates COVID-19 was first transmitted in a wildlife market in Wuhan. The disease likely originated in pangolins, bats, or a combination of both and was then transmitted to humans.

While various commentators have blamed pangolins, bats, or even our lack of “mastery” of wildlife, the real cause of this pandemic goes deeper – into the laws, cultures and institutions of most countries.




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At the root of the problem is a social phenomenon called “human-wildlife conflict”. This is when the interests of humans and the needs of wildlife overlap in a negative way.

Both the illegal wildlife trade and zoonotic diseases (that is, diseases transmitted from animals to humans) are aspects of human-wildlife conflict.

This ubiquitous phenomenon is poorly addressed in both international and domestic laws. And this grave omission has led to disastrous effects on humanity, as COVID-19 has shown.

A complex international issue

Disease outbreaks stemming from human-wildlife conflict are not new or limited to the Chinese wildlife trade. Ebola, for example, originated in the Western African country of Gabon. It was likely spread from a chimpanzee that was hunted and eaten by local people.

The Ebola virus could be connected to poverty in Gabon.
Shutterstock

Sometimes the disease itself creates the conflict. Hendra, a zoonotic disease confined to Australia, was passed from fruit bats to horses and then to humans. The outbreak prompted calls for fruit bats to be culled.

Research shows environmental destruction is also leading to an increase in zoonotic diseases. For example, clearing forests and destroying habitats can force animals to move closer to urban areas, bringing diseases with them.




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COVID-19 and Ebola can also be connected to poverty, as wildlife hunting is often connected to a basic need for food. Culture, politics, health, issues of gender equality and economics (to name a few), are all connected to human-wildlife conflicts as well.

The widespread impact of these types of viruses that can spread across international borders means that they should be governed as an international issue.

But there are no consistent international or domestic laws to guide governance of the multiple and interacting causes of pandemics.

Laws don’t go far enough

The human-wildlife relationship goes beyond issues of conservation and animal welfare, yet many of the world’s laws designed to tackle these multidimensional problems do not.

A select few laws have sought to implement a whole-systems approach to legal decision-making. For example, the Convention on Biological Diversity, an international treaty, requires ecosystem managers to consider the impact of environmental decision-making on multiple parts of society, including levels of poverty and economics.




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But this holistic approach isn’t reflected in domestic laws around the world that are supposed to enforce international treaties, such as Australia’s Environmental Protection and Biodiversity Conservation Act, which is currently under review by the federal government.

Collaborations, such as between health law and conservation law, must be put in place. For example, while the World Health Organisation works on zoonose (animal-borne disease) prevention, there is little interaction between it and the Convention on the International Trade of Endangered Species.

No quick fix

Our legal systems – especially in the West and in international law – encourage separation and domination of the environment.

For example, the laws that designate protected areas explicitly separate people from wildlife, and this can drastically change the relationship between them. Laws also continue to encourage domination via implicit means, such as through legalised wildlife hunting and trade.

Don’t blame bats for the spread of Hendra virus.
Shutterstock

Various changes to law have been proposed in light of COVID-19, including closing all wildlife markets and trade.

But these types of fixes don’t address the many ways our health can be affected by wildlife use. Nor do they consider the poverty that often drives the consumption of wildlife, such as in Gabon and the other multiple causal factors.




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Such blanket legal prohibitions are neither appropriate nor adequate. We need legal changes on a larger scale. Laws must acknowledge how all humans are vulnerable to wildlife and broader environment change. If they haven’t even acknowledged this, then they can’t start to address it.

What needs to change?

Changes to the law at both the international and domestic level should focus on two primary areas.

First, increased cooperation is required between systems and areas of law in addressing the source of our vulnerability, instead of waiting for the vulnerability to become catastrophic, such as with COVID-19.

Second, both international and domestic laws must recognise the interdependency between humans and all aspects of the natural environment, in every area of law – from environmental law, to trade law, human rights and corporate law.

Ecuador, for example, integrated this idea into its national constitution so the necessity of environmental protection is linked to the continued existence of its people.




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Another way is to integrate nature into the objectives of each piece of law. This includes all international treaties and domestic pieces of legislation, even those that do not expressly deal with matters of the environment, such as health law, where a healthy environment is directly linked to human health.

No, this is not a small undertaking. But as the catastrophe of COVID-19 has demonstrated, the problems we face if we don’t change are far more onerous in all aspects of our lives.The Conversation

Katie Woolaston, Lawyer, Queensland University of Technology

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

Where the wild things are: how nature might respond as coronavirus keeps humans indoors



AP News

Sarah Bekessy, RMIT University; Alex Kusmanoff, RMIT University; Brendan Wintle, University of Melbourne; Casey Visintin, University of Melbourne; Freya Thomas, RMIT University; Georgia Garrard, RMIT University; Katherine Berthon, RMIT University; Lee Harrison, University of Melbourne; Matthew Selinske, RMIT University, and Thami Croeser, RMIT University

Intriguing things sometimes happen in places deserted by people. Plants creep back, animals return and, slowly, birdsong fills the air.

The coronavirus pandemic means public spaces the world over have been temporarily abandoned. Major roads are all but empty and public squares are eerily quiet.

In response, nature is in some cases “taking over towns”. Some reports – such as dolphins spotted in Venice – are fake news. But others are legitimate.




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A puma has been spotted roaming the streets of Santiago and wild turkeys are gallivanting in Oakland, California. Monkeys have reclaimed city streets in Thailand and deer are wandering through train stations and down roads in Japan.

Of course, COVID-19 has taken a devastating toll on humanity, and this is nothing to be celebrated. But as Australians stay at home and our streets fall quiet, let’s consider how wildlife might respond.

Animals the world over are creeping back into cities deserted due to COVID-19.
SOHAIL SHAHZAD/EPA

The resilience of nature

Throughout history, nature has shown a propensity for reclaiming land once humans have departed.

At Chernobyl, for instance, radiation has not been enough to suppress populations of gray wolves, raccoon dogs, Eurasian boar and red fox.

Likewise the Korean demilitarised zone has become a refugia for numerous threatened species, including red-crowned cranes.

Ecological succession can occur when humans abandon cities. This is where short-lived “pioneer” species initially occupy sites and are replaced over time by shrubs and trees, ultimately supporting more diverse wildlife.

It’s hard to predict exactly how healthy and biodiverse these systems can become, but they will almost certainly be examples of “novel ecosystems”, having crossed irreversible thresholds due to human impact, such as vegetation reclaiming an abandoned building.

A butterfly on a floor in front of visitors in protective shoes at the Chernobyl nuclear power plant in April 2018.
SERGEY DOLZHENKO/EPA

Quieter, darker, greener cities

Cities can be hostile places for urban wildlife due to fragmented habitat, pollution, road collisions and disturbance from and conflict with people. But under a coronavirus lockdown, these threats are greatly reduced.

For example, decreases in economic activity in Europe and China have led to improvements in air pollution, which is known to badly affect urban birds. However, this effect might not last long enough to allow for recovery of sensitive bird species; emissions in China are already rising again.




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Light pollution may also fall in cities as a result of coronavirus – such as if office buildings turn off overnight lighting and sportsgrounds are empty.

This would benefit nocturnal species such as moths and bats. Artificial light can interfere with reproduction, predator and prey interactions, and migration.

At the end of March, traffic congestion in Sydney and Melbourne was reportedly down more than 30% on last year. Fewer cars and trams would benefit species that communicate acoustically (such as frogs and birds).

Empty roads near Circular Quay in Sydney on March 27 this year.
JAMES GOURLEY/AAP

Fewer people actively using city spaces may mean less disturbance of urban bird nesting sites, especially those that are routinely removed from commercial properties.

Depending on whether authorities see weed control as an “essential service”, streets may soon look a bit greener.

Weeds often get a bad rap for taking over gardens and roadsides. However, some, such as dandelions, provide excellent flowering resources for native bees, butterflies and birds.

Deserted roads could potentially add to existing wildlife “corridors” or strips of vegetation along rivers and streams. This would allow species to move from one place to another – potentially recolonising areas.

What next?

Once traffic returns to levels observed before the pandemic, we should preserve observed animal movements using safe passage strategies such as vegetated overpasses that connect bisected habitat or adequately sized underpasses to allow wildlife to safely cross under large, busy roads.

Nature can reclaim places that have been totally abandoned for years, creating novel ecosystems.
Pixabay, CC BY

In the longer term, this crisis may bring innovation in business communication and human behavioural change – including reduced work travel. This could influence land-use changes in cities, potentially giving space back to nature.

The current need for people to stay at home might be triggering a human disconnection from nature. In some cases, this can lead people to become emotionally distanced from what happens to their natural environment. This could be ameliorated by exercising in local parks or other natural environments.

You can also use your time at home to positively contribute to wildlife in your urban area. If you’re looking to keep kids entertained, try developing a “renaturing” plan that aims to care for, or bring back, a species or ecosystems.

There are also many ways to retrofit your home, garden or balcony to help plants and animals.

Or discover the incredible species living alongside us by simply paying attention to nature near your home.




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The Conversation


Sarah Bekessy, Professor in Sustainability and Urban Planning, Leader, Interdisciplinary Conservation Science Research Group (ICON Science), RMIT University; Alex Kusmanoff, Postdoctoral Research Fellow, Inter-disciplinary Conservation (ICON) Science Research Group, RMIT University; Brendan Wintle, Professor in Conservation Ecology, School of BioSciences, University of Melbourne; Casey Visintin, Postdoctoral Research Fellow, School of BioSciences, University of Melbourne; Freya Thomas, Research Fellow, Centre for Urban Research, RMIT University; Georgia Garrard, Senior Research Fellow, Interdisciplinary Conservation Science Research Group, RMIT University; Katherine Berthon, PhD Candidate, RMIT University; Lee Harrison, Honorary Associate, University of Melbourne; Matthew Selinske, Postdoctoral research associate conservation science, RMIT University, and Thami Croeser, Research Officer, Centre for Urban Research, RMIT University

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

Camera traps completed one of the most thorough surveys of African rainforest yet



PNS Survey, Author provided

Mattia Bessone, Liverpool John Moores University and Barbara Fruth, Liverpool John Moores University

Tropical rainforests are the world’s richest land habitats for biodiversity, harbouring stunning numbers of plant and animal species. The Amazon and the Congo basins, together with Asian rainforests, represent only 6% of Earth’s land surface, and yet more than 50% of global biodiversity can be found under their shade.

But observing even the most conspicuous species, such as elephants and apes, is still an extraordinarily difficult task. That’s not even mentioning all the secretive species that are protected by thick vegetation or darkness.

Camera traps have led a technological revolution in wildlife research, making it possible to study species without humans needing to be present. They can be left in the depths of a forest for weeks, taking pictures of anything that moves at any time of day or night.

Installing camera traps in Salonga National Park.
Jonas Abana Eriksson/PNS Survey, Author provided

From their advent three decades ago, camera traps have allowed scientists to discover species such as the grey-faced sengi – a new species of giant elephant shrew living in Tanzania – and the Annamite striped rabbit in Vietnam. They revealed that lions still wander the Bateke plateau in Gabon, ending speculation that they were locally extinct. They also photographed the offspring of the elusive Javan rhino, which scientists had thought had stopped breeding. With fewer than 100 individuals left, this gave hope that the species could be saved from extinction.

The grey-faced sengi (Rhynchocyon udzungwensis) was discovered by camera traps in Tanzania.
F Rovero/Wikipedia, CC BY-SA

Spotting stripes

Camera traps are becoming essential for documenting forest species, assessing their distribution and studying their behaviour, as well as counting what’s actually there.

This latter measure, called animal abundance, is perhaps the most important information in wildlife conservation, as it allows researchers to assess the conservation status of a species. But until recently, camera traps could only be used to reliably estimate the abundance of animals with conspicuous markings, such as big cats with spots or stripes peculiar to single individuals.

Big cats, like this African leopard (Panthera pardus), are among the simplest species to document with camera traps.
Haplochromis/Wikipedia, CC BY-SA

Counting animals with camera traps remained impossible for the majority of species that lacked these conspicuous features, as the same individual could be counted twice by different cameras at different times. Methods that account for how animals move in and use their habitat were developed to help overcome the problem of detecting the same individual at different locations.

Another method, called camera trap distance sampling achieves the same result using a different approach. It subdivides the time cameras are active into “snapshots”, taking pictures at, for example, every fifth second in an hour. At a determined moment, an individual can only be spotted at one location, not elsewhere. Double counts are avoided, and researchers get the number of animals within the area surveyed by the cameras at a given snapshot.

We tested this new method in one of the most remote areas of the planet – the southern part of Salonga National Park, a world heritage site in the Democratic Republic of the Congo. Here, rangers only had data on the park’s two flagship species – the forest elephant and the bonobo. Near to nothing was known about the other animals that were more difficult to track.

A flagship species of Salonga National Park, bonobo populations are understudied in 70% of their range.
Christian Ziegler/LKBP, Author provided

What we found

Five field teams walked a forest the size of Wales to deploy 160 camera traps in 743 places. This unprecedented effort produced more than 16,000 video clips, totalling 170 hours of animal footage and revealing 43 different animal species, including bonobos and elephants.

We also captured species rarely detected by human observers, such as the giant ground pangolin, threatened by extinction, the cusimanses, a genus of social mongooses, and the stunning Congo peafowl, a vulnerable species that’s endemic to the country.

Where so far conservation of elusive species such as the African golden cat, the endemic Allen’s swamp monkey and another elephant shrew, the four-toed sengi, had to be based on little to no data, we’re now able to estimate their abundance in the wild.

Nine of 43 species captured by camera traps in Salonga National Park, DRC.
PNS Survey, Author provided

For some species, the news from our findings were good. Our study revealed that the southern part of Salonga National Park alone harboured as many peafowls as were previously thought to be present in the whole country.

For other species, the results confirmed the need for greater protection. The 17,000 km² large and intact primary rain forest contains fewer than 1,000 giant pangolins. An alarming figure given the current illegal trade of pangolin scales.

As the technology and methods of camera trap surveys improve, they’re becoming capable of monitoring a diverse range of wildlife, from the tiny elephant shrew to the mighty forest elephant. This gives an insight into the complex and delicate equilibrium of the rainforest community and the threats to its survival.The Conversation

Mattia Bessone, PhD Researcher in Conservation Biology, Liverpool John Moores University and Barbara Fruth, Associate Professor, Liverpool John Moores University

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

Coronavirus: what the lockdown could mean for urban wildlife



‘Today, the pond. Tomorrow, the world!’
Patrick Robert Doyle/Unsplash, CC BY-SA

Becky Thomas, Royal Holloway

As quarantine measures take hold across the world, our towns and cities are falling silent. With most people indoors, the usual din of human voices and traffic is being replaced by an eerie, empty calm. The wildlife we share our concrete jungles with are noticing, and responding.

You’ve probably seen posts on social media about animals being more visible in urban centres. Animals that live in cities or on their outskirts are exploring the empty streets, like the Kashmiri goats in Llandudno, Wales. Others that would normally only venture out at night are becoming bolder and exploring during the daytime, like the wild boar in Barcelona, Spain.

Our new habits are altering the urban environment in ways that are likely to be both positive and negative for nature. So which species are likely to prosper and which are likely to struggle?

Hooray for hedgehogs

It’s important to note some species may be unaffected by the lockdown. As it coincides with spring in the northern hemisphere, trees will still bud and flower and frogs will continue to fill garden ponds with frog spawn. But other species will be noticing our absence.

The way we affect wildlife is complex, and some of the changes that we’ll see are hard to predict, but we can make some assumptions. In the UK, hedgehogs are our most popular mammal, but their numbers are in rapid decline. There are many reasons for this, but many die on roads after being hit by cars. With people being asked to only make essential journeys, we are already seeing reduced road traffic. Our spiny friends will have just emerged from hibernation and will no doubt be grateful for the change.

The lockdown could be well timed for hedgehogs emerging from hibernation.
Besarab Serhii/Shutterstock

Cities are also noisy places, and the noise affects how different species communicate with each other. Birds have to sing louder and at a higher pitch than their rural counterparts, which affects the perceived quality of their songs. With reduced traffic noise, we could see differences in how bats, birds and other animals communicate, perhaps offering better mating opportunities.

School closures may not be ideal for working parents, but many will use their time to connect with nature in their own backyard. More time spent in gardens (for those lucky enough to have one), perhaps doing activities like making bird feeders, could help encourage nature close to home. There’s been a surge in people taking part in citizen science projects like the Big Butterfly Count too. These help scientists to predict the population trends of different species. The British Trust for Ornithology has just made participation in their Garden BirdWatch Project free during the lockdown, so you can connect with wildlife and contribute to important scientific research.




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Desolation for ducks

All is not rosy for wildlife. Many species currently rely on food provided by humans. From primates fed by tourists in Thailand, to the ducks and geese at local parks which have been closed to the public, many animals may be seeking new sources of food.

In the UK, the bird breeding season has already begun for earlier breeders like robins. Depending on how long restrictions last, many birds could ultimately make bad decisions about where to breed, assuming their carefully chosen spot is always rarely disturbed. This could threaten rarer birds which breed in the UK, such as little terns, as dog walkers and other people flock to beaches once restrictions are lifted, potentially trampling and disturbing breeding pairs and their young.

A little tern sheltering eggs on an open beach.
BOONCHUAY PROMJIAM/Shutterstock

Dog walkers also enjoy lowland heathlands, especially those near urban areas such as Chobham Common in Surrey. These rare heaths are home to many rare bird species, like Dartford warblers, which could also see their nests disturbed once humans begin to emerge again in larger numbers. People who are enthralled by wildlife venturing into new areas during lockdown will need to carefully manage their return to the outdoors once restrictions are lifted.

Though some species may face challenges in now silent towns and cities, those species that live alongside us do so because they are so adaptable. They will find new sources of food, and will exploit new opportunities created in our absence. Hopefully this time will allow people to appreciate their local environments more, and find new ways to nurture them once all this is over.The Conversation

Becky Thomas, Senior Teaching Fellow in Ecology, Royal Holloway

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

Social distancing works – just ask lobsters, ants and vampire bats



Caribbean spiny lobsters normally live in groups, but healthy lobsters avoid members of their own species if they are infected with a deadly virus.
Humberto Ramirez/Getty Images

Dana Hawley, Virginia Tech and Julia Buck, University of North Carolina Wilmington

Social distancing to combat COVID-19 is profoundly impacting society, leaving many people wondering whether it will actually work. As disease ecologists, we know that nature has an answer.

Animals as diverse as monkeys, lobsters, insects and birds can detect and avoid sick members of their species. Why have so many types of animals evolved such sophisticated behaviors in response to disease? Because social distancing helps them survive.

In evolutionary terms, animals that effectively socially distance during an outbreak improve their chances of staying healthy and going on to produce more offspring, which also will socially distance when confronted with disease.

We study the diverse ways in which animals use behaviors to avoid infection, and why behaviors matter for disease spread. While animals have evolved a variety of behaviors that limit infection, the ubiquity of social distancing in group-living animals tells us that this strategy has been favored again and again in animals faced with high risk of contagious disease.

What can we learn about social distancing from other animals, and how are their actions like and unlike what humans are doing now?

Feed the sick, but protect the queen

Social insects are some of the most extreme practitioners of social distancing in nature. Many types of ants live in tight quarters with hundreds or even thousands of close relatives. Much like our day care centers, college dormitories and nursing homes, these colonies can create optimal conditions for spreading contagious diseases.

In response to this risk, ants have evolved the ability to socially distance. When a contagious disease sweeps through their society, both sick and healthy ants rapidly change their behavior in ways that slow disease transmission. Sick ants self-isolate, and healthy ants reduce their interaction with other ants when disease is present in the colony.

Healthy ants even “close rank” around the most vulnerable colony members – the queens and nurses – by keeping them isolated from the foragers that are most likely to introduce germs from outside. Overall, these measures are highly effective at limiting disease spread and keeping colony members alive.

Many other types of animals also choose exactly who to socially distance from, and conversely, when to put themselves at risk. For example, mandrills – a type of monkey – continue to care for sick family members even as they actively avoid sick individuals to whom they are not related. In an evolutionary sense, caring for a sick family member may allow an animal to pass on its genes through that family member’s offspring.

Mandrills live in large groups in the rainforests of equatorial Africa. They will often groom other group members, but actively avoid sick mandrills unless they are close family members.
Eric Kilby/Wikipedia, CC BY-SA

Further, some animals maintain essential social interactions in the face of sickness while foregoing less critical ones. For example, vampire bats continue to provide food for their sick groupmates, but avoid grooming them. This minimizes contagion risk while still preserving forms of social support that are most essential to keeping sick family members alive, such as food sharing.

These nuanced forms of social distancing minimize costs of disease while maintaining the benefits of social living. It should come as no surprise that evolution favors them in many types of animals.

Altruism makes us human

Human behavior in the presence of disease also bears the signature of evolution. This indicates that our hominid ancestors faced many of the same pressures from contagious disease that we are facing today.

Like social ants, we are protecting the most vulnerable members of our society from COVID-19 infection by ensuring that older individuals and those with pre-existing conditions stay away from potentially contagious people. Like monkeys and bats, we also practice nuanced social distancing, reducing non-essential social contacts while still providing essential care for sick family members.

A black garden ant queen (upper left), surrounded by adult ants, larvae (left), eggs (middle) and a cocoon (right).
Pan weterynarz/Wikipedia, CC BY-SA

There also are important differences. For example, in addition to caring for sick family members, humans sometimes increase their own risk by caring for unrelated individuals, such as friends and neighbors. And health care workers go further, actively seeking out and helping precisely those who many of us carefully avoid.

Altruism isn’t the only behavior that distinguishes human response to disease outbreaks. Other animals must rely on subtle cues to detect illness among group members, but we have cutting-edge technologies that make it possible to detect pathogens rapidly and then isolate and treat sick individuals. And humans can communicate health threats globally in an instant, which allows us to proactively institute behaviors that mitigate disease. That’s a huge evolutionary advantage.

Finally, thanks to virtual platforms, humans can maintain social connections without direct physical contact. This means that unlike other animals, we can practice physical rather than social distancing, which lets us preserve some of the important benefits of group living while minimizing disease risk.

Worth the disruption

The evidence from nature is clear: Social distancing is an effective tool for reducing disease spread. It is also a tool that can be implemented more rapidly and more universally than almost any other. Unlike vaccination and medication, behavioral changes don’t require development or testing.

However, social distancing can also incur significant and sometimes unsustainable costs. Some highly social animals, like banded mongooses, do not avoid group members even when they are visibly sick; the evolutionary costs of social distancing from their relatives may simply be too high. As we are currently experiencing, social distancing also imposes severe costs of many kinds in human societies, and these costs are often borne disproportionately by the most vulnerable people.

Given that social distancing can be costly, why do so many animals do it? In short, because behaviors that protect us from disease ultimately allow us to enjoy social living – a lifestyle that offers myriad benefits, but also carries risks. By implementing social distancing when it’s necessary, humans and other animals can continue to reap the diverse benefits of social living in the long term, while minimizing the costs of potentially deadly diseases when they arise.

Social distancing can be profoundly disruptive to our society, but it can also stop a disease outbreak in its tracks. Just ask ants.

[You need to understand the coronavirus pandemic, and we can help. Read The Conversation’s newsletter.]The Conversation

Dana Hawley, Professor of Biological Sciences, Virginia Tech and Julia Buck, Assistant Professor of Biology, University of North Carolina Wilmington

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