Birds that play with others have the biggest brains – and the same may go for humans



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Gisela Kaplan, University of New England

Have you ever seen magpies play-fighting with one another, or rolling around in high spirits? Or an apostlebird running at full speed with a stick in its beak, chased by a troop of other apostlebirds? Well, such play behaviour may be associated with a larger brain and a longer life.

For the past 50 years, international animal cognition research has often related the use of tools such as rocks and sticks to cognitive abilities in animals. But my research on Australian native birds, published in Scientific Reports, casts doubt on long-held assumptions about the links between large brains and tool use.

My study found no significant association between tool use and brain mass. However, very clear differences in relative brain mass emerged when birds showing play behaviour were compared to those that didn’t play. In particular, birds that played with others (known as social play) had the largest brain mass, relative to body size, and even the longest lifespans.

The results suggest play behaviour may be an important driver in the evolution of large brains in a number of species, including humans.

Magpie engaged in play
Magpies engaged in complex social play. One magpie hung solo from a towel on a washing line then was joined by others. One newcomer pulled the hanging magpie’s foot to make it swing, and the other gave it a push back the other way, and so on.
The Magpie Whisperer

Tool use in birds

Tool use has been studied in a wider range of species than play behaviour. Some internationally famous Australian examples include:

  • the black-breasted buzzard releasing rocks from their beaks to crack emu eggs

  • the black kite picking up burning embers and twigs and dropping them on dry grass areas to start a fire. The bird then feasts on fleeing or injured insects and vertebrates

  • palm cockatoos that drum with a stick.

According to a classic theory known as the “technical intelligence hypothesis”, humans and other animals developed large brains because circumstances forced them into ever more sophisticated tool use.




Read more:
Bird-brained and brilliant: Australia’s avians are smarter than you think


Palm cockatoos drum with a stick.

So what is bird play?

Play behaviour usually occurs in juveniles but in some species, such as little corellas or galahs, it extends into adulthood. Play behaviour occurs in species which tend to have long juvenile periods, long-term support from parents and which grow up in stable social groups.

Play behaviour is usually subdivided into three categories: solo play, object play and social play.

Solo play: this may involve a single bird running, skipping, jumping, ducking, rolling, hanging, swinging, dancing, sliding and snow-romping. Solo play is the most widespread form of play, common among honeyeaters, parrots, magpies, currawongs, butcherbirds, riflebirds and some pigeon species.

The best acrobat among the pigeons is probably the topknot pigeon, but rainbow lorikeets are also known to love swinging.

Object play: this involves objects of any kind, including sticks, stones and small household items. Object players might carry a stick or stone or even just a leaf around, drop it, then pick it up again and run with it.

Object players are not as numerous as solo players but still widespread across species. Click here to read a lovely description of a kookaburra absorbed in playing with a stone.

Social play: involves two or more individuals. Social play is so far the rarest category. It might involve one bird holding an object in its beak and the others chasing it. Published cases are largely limited to parrots and corvids, and are known in magpies and ravens.




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White-winged choughs are known to play a game in which two youngsters simultaneously grab a small stick or a bunch of grass, then each tries to wrest it from the other.

It’s important to note that social players are also solo and object players, but solo or object players may not be social players. The latter is considered a more complex form of play.

It turns out these categories are meaningful when used to analyse a potential link to brain mass. Information on brain weight/mass in Australian birds has been available only since an important study in 2014. It identified brain volumes and body sizes of all Australian bird species, enabling researchers to link these biological data to behavioural data.

A little corella holding onto a wire by the beak and trying to swing.
A little corella performing a daredevil solo stunt — holding onto a wire by the beak and trying to swing.
Gisela Kaplan

A surprising link

My study involved 77 native Australian bird species for which full data sets were available. The results were more than surprising. In the samples used, tool use seems to confer no advantage whatsoever in terms of brain size or life expectancy: no matter whether a species showed tool using or not, relative brain masses were not different. However the results showed, rather dramatically, that brain size and forms of play are associated.

Social players, versus other players and versus non-players showed significantly different average brain sizes in each category:

  • non players have the lowest average brain size

  • solo players had slightly larger brains than non-players

  • object players had larger brains again

  • social players had by far the largest average brain size relative to body weight.

These results are by no means confined to parrots, but are found in songbirds and other orders. Whether this holds for birds globally is not yet known. However, since parrots and songbirds first evolved in Australia, then spread to the rest of the world, the results may indeed hold for birds outside Australia. More research will be needed.




Read more:
Magpies can form friendships with people – here’s how


Which came first – play resulting in large brains or large brains triggering play behaviour – is not known. But whichever way one looks at it, playing socially or even just playing at all, is related to a bigger brain and a long life.

So what does all this mean for human brain evolution? It may be a long shot, but the stages of development in humans and birds seem to have some similarities and this may be significant.

Offspring in humans, as in great apes and other primates, also develop slowly, have protracted childhoods and play extensively as do a surprising number of Australian native birds. It may mean playing together offers more than just passing the time. It could be an evolutionary driver for intelligence, and even for a long life.The Conversation

Gisela Kaplan, Emeritus Professor in Animal Behaviour, University of New England

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

These are the plastic items that most kill whales, dolphins, turtles and seabirds



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Lauren Roman, CSIRO; Britta Denise Hardesty, CSIRO; Chris Wilcox, CSIRO, and Qamar Schuyler, CSIRO

How do we save whales and other marine animals from plastic in the ocean? Our new review shows reducing plastic pollution can prevent the deaths of beloved marine species. Over 700 marine species, including half of the world’s cetaceans (such as whales and dolphins), all of its sea turtles and a third of its seabirds, are known to ingest plastic.

When animals eat plastic, it can block their digestive system, causing a long, slow death from starvation. Sharp pieces of plastic can also pierce the gut wall, causing infection and sometimes death. As little as one piece of ingested plastic can kill an animal.

About eight million tonnes of plastic enters the ocean each year, so solving the problem may seem overwhelming. How do we reduce harm to whales and other marine animals from that much plastic?

Like a hospital overwhelmed with patients, we triage. By identifying the items that are deadly to the most vulnerable species, we can apply solutions that target these most deadly items.

Some plastics are deadlier than others

In 2016, experts identified four main items they considered to be most deadly to wildlife: fishing debris, plastic bags, balloons and plastic utensils.

We tested these expert predictions by assessing data from 76 published research papers incorporating 1,328 marine animals (132 cetaceans, 20 seals and sea lions, 515 sea turtles and 658 seabirds) from 80 species.

We examined which items caused the greatest number of deaths in each group, and also the “lethality” of each item (how many deaths per interaction). We found the experts got it right for three of four items.

Plastic bag floats in the ocean.
Film plastics cause the most deaths in cetaceans and sea turtles.
Shutterstock

Flexible plastics, such as plastic sheets, bags and packaging, can cause gut blockage and were responsible for the greatest number of deaths over all animal groups. These film plastics caused the most deaths in cetaceans and sea turtles. Fishing debris, such as nets, lines and tackle, caused fatalities in larger animals, particularly seals and sea lions.

Turtles and whales that eat debris can have difficulty swimming, which may increase the risk of being struck by ships or boats. In contrast, seals and sea lions don’t eat much plastic, but can die from eating fishing debris.

Balloons, ropes and rubber, meanwhile, were deadly for smaller fauna. And hard plastics caused the most deaths among seabirds. Rubber, fishing debris, metal and latex (including balloons) were the most lethal for birds, with the highest chance of causing death per recorded ingestion.




Read more:
We estimate up to 14 million tonnes of microplastics lie on the seafloor. It’s worse than we thought


What’s the solution?

The most cost-efficient way to reduce marine megafauna deaths from plastic ingestion is to target the most lethal items and prioritise their reduction in the environment.

Targeting big plastic items is also smart, as they can break down into smaller pieces. Small debris fragments such as microplastics and fibres are a lower management priority, as they cause significantly fewer deaths to megafauna and are more difficult to manage.

Image of dead bird and gloved hand containing small plastics.
Plastic found in the stomach of a fairy prion.
Photo supplied by Lauren Roman

Flexible film-like plastics, including plastic bags and packaging, rank among the ten most common items in marine debris surveys globally. Plastic bag bans and fees for bags have already been shown to reduce bags littered into the environment. Improving local disposal and engineering solutions to enable recycling and improve the life span of plastics may also help reduce littering.

Lost fishing gear is particularly lethal. Fisheries have high gear loss rates: 5.7% of all nets and 29% of all lines are lost annually in commercial fisheries. The introduction of minimum standards of loss-resistant or higher quality gear can reduce loss.




Read more:
How to get abandoned, lost and discarded ‘ghost’ fishing gear out of the ocean


Other steps can help, too, including

  • incentivising gear repairs and port disposal of damaged nets

  • penalising or prohibiting high-risk fishing activities where snags or gear loss are likely

  • and enforcing penalties associated with dumping.

Outreach and education to recreational fishers to highlight the harmful effects of fishing gear could also have benefit.

Balloons, latex and rubber are rare in the marine environment, but are disproportionately lethal, particularly to sea turtles and seabirds. Preventing intentional balloon releases and accidental release during events and celebrations would require legislation and a shift in public will.

The combination of policy change with behaviour change campaigns are known to be the most effective at reducing coastal litter across Australia.

Reducing film-like plastics, fishing debris and latex/balloons entering the environment would likely have the best outcome in directly reducing mortality of marine megafauna.




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The Conversation


Lauren Roman, Postdoctoral Researcher, Oceans and Atmosphere, CSIRO; Britta Denise Hardesty, Principal Research Scientist, Oceans and Atmosphere Flagship, CSIRO; Chris Wilcox, Senior Principal Research Scientist, CSIRO, and Qamar Schuyler, Research Scientist, Oceans and Atmospheres, CSIRO

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

Friday essay: in praise of pardalotes, unique birds living in a damaged country




John Woinarski, Charles Darwin University

I’ve spent more of my life with pardalotes than with most other acquaintances. They are an obscure and odd group of four species of small (thumb-sized) birds. They have little public profile, not helped by the awkward name. But they are quintessentially Australian, occurring nowhere else in the world.

As a boy, I chanced upon a pair of spotted pardalotes absorbed in constructing their nesting burrow, a long tunnel built into sloping earth. Whereas most of the bird’s existence is spent unobtrusively foraging in tree canopies, breeding brings this species to ground, allowing close observation by the quiet but inquisitive.

My interest was piqued by their industry, beauty and strangeness. The intrigue stayed with me. Later, a PhD in zoology gave me the opportunity to study them in detail.

The author as a young man, with a pardalote.
Author provided

Zoology is a charmed science. Done well, it offers the opportunity to escape the conformity, constraints and solipsism of the human perspective; to see and understand the world from the viewpoint of another species, where space and time differ from the conventions we’re used to, where the ordering of the importance of things is upended, where the elements of the natural world come far more sharply into focus and are imbued with different meanings.

Zoology offers shapeshifting, and the insights that brings. It has taken me to many places, and a little into the diverse minds of remarkable species.

Adapted to Australia

So, for three years I counted pardalotes at many sites and over many seasons.
I caught thousands, with wire-mesh traps at the entrances to their nesting burrows or with carefully sited nets. I attached leg bands, so I
knew the identity of individuals. I weighed them, measured them, described the subtle variations in their jewelled plumage.

I watched them for hours every day, recording the plant species in which they foraged, and what they ate. I studied their mating habits, their breeding success, their territoriality and social interactions.

I reassessed my initial conception of them as placid when my experiments with a dummy pardalote and call playback triggered violent responses from territorial males. I examined the factors that threatened and killed them.

I found that they have long adapted to and exemplify an Australian ecology: they fit this country well.

They forage almost entirely in eucalypts, that linchpin and defining feature of many Australian environments. Their diet is unusual, comprising mostly the sweet exudate (manna) that seeps from eucalypt foliage, and “lerp”, the sugary coating of psyllid insects (a specialised group of bugs) that suck the phloem (the “sap” in leaves) from within that foliage.

A spotted pardalote feeding.
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This strange resource is itself a consequence of the Australian environment – our soils are typically so poor that trees capturing nutrients must also drink up an excess of carbohydrates that they then need to secrete.

The eucalypt/lerp/pardalote web is an intricate arrangement, played out in kaleidoscopic variation in different regions, with varying eucalypt, psyllid and pardalote species.

Season adds a further dynamic to the landscape, with insect abundance diminishing in cooler areas in winter. So, like many other animal species, the pardalotes must track the ebb and flow of resources across our country, else stay put and starve.

Indeed, episodes of mass mortality of pardalotes have been recorded in some winters. Some populations of these tiny birds cross formidable Bass Strait each year, heading from Tasmanian summers to the mainland for winter. Others disperse in a less orderly manner, nomadically tracking more unpredictable booms and busts of psyllid populations.

Subverted pathways

The forty-spotted pardalote, seen here on a postage stamp, is now endangered.
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Such nomadic movement is a distinctive feature of many Australian birds, contrasting markedly with the more rigid migration routes typical of birds on other continents – our seasonal patterning is more subtle and complex. But the ageless dispersal pathways of pardalotes have been subverted.

Clearing has broken the continuity of the forests, rendering dispersal more hazardous. In little more than 200 years, about 40% of their forest home has been destroyed, directly causing a comparable proportional loss in their population size.

Pardalotes have other threats. Around 10% of their habitat was burned in the severe wildfires of 2019–20, with those fires most likely killing the birds directly, and leaving burned habitat unsuitable for their re-establishment for at least several years.




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In many parts of their range, the manner in which we have degraded and fragmented their forest and woodland habitat has benefitted a small suite of aggressive honeyeaters – the native noisy miner and bell miner – and these miners can kill pardalotes and exclude them from otherwise suitable habitat.

Ecology is a complex network with many interwoven threads, and manipulation of one thread can have many reverberating impacts. We play with those threads at our peril.

From a human perspective, our land is mostly familiar, comforting.

But studying any Australian animal almost always leads to a crystallisation, a deciphering, of the destabilising manner in which we’ve contorted the ecology of this place. Purposefully, incompetently or haphazardly, we have rearranged the ecology of this land to suit our needs, and in doing so have rubbed away much that was integral to the existence of many other species.

We are corroding our nature and will pass on to our descendants a land that is less healthy, less diverse, less wonderful.

Notwithstanding the less secure life most pardalotes now face, three pardalote species remain reasonably abundant and widespread. However, one species – the forty-spotted pardalote (a charming and apt name) – has been particularly hard-hit by the changes we have wrought to its environment.

A forty-spotted pardalote.
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Now recognised as endangered, it has declined extensively and been reduced to a few populations (in beautiful locations) on some islands off Tasmania, with a fragile toehold at several small sites on the Tasmanian mainland. We still have the chance to save it, but that opportunity may soon be lost.

I no longer study pardalotes. But in the soundscape of my days, their intermittent call can still lure me away into lives that are not my own, into different ways of knowing our country and its workings, of the damage we’ve done and the healing we have yet to do.

This is an edited extract from Animals Make Us Human ed. Leah Kaminsky and Meg Keneally (Penguin Life, RRP $29.99), available now.The Conversation

John Woinarski, Professor (conservation biology), Charles Darwin University

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

Scientists at work: Sloshing through marshes to see how birds survive hurricanes



A clapper rail with a fiddler crab in its bill.
Michael Gray, CC BY-ND

Scott Rush, Mississippi State University and Mark Woodrey, Mississippi State University

When storms like Huricane Zeta menace the Gulf Coast, residents know the drill: Board up windows, clear storm drains, gas up the car and stock up on water, batteries and canned goods.

But how does wildlife ride out a hurricane? Animals that live along coastlines have evolved to deal with a world where conditions can change radically. This year, however, the places they inhabit have borne the brunt of 10 named storms, some just a few weeks apart.

As wildlife ecologists, we are interested in how species respond to stresses in their environment. We are currently studying how marsh birds such as clapper rails (Rallus crepitans) have adapted to tropical storms along the Alabama and Mississippi Gulf coast. Understanding how they do this entails wading into marshes and thinking like a small, secretive bird.

Least bittern in marsh grass
A least bittern, one of the smallest species of heron.
Michael Gray, CC BY-ND

Mucky and full of life

Coastal wetlands are critically important ecosystems. They harbor fish, shellfish and wading birds, filter water as it flows through and buffer coastlines against flooding.

You wouldn’t choose a Gulf Coast salt marsh for a casual stroll. There are sharp-pointed plants, such as black needlerush​, and sucking mud. In summer and early fall the marshes are oppressively hot and humid. Bacteria and fungi in the mud break down dead material, generating sulfurous-smelling gases. But once you get used to the conditions, you realize how productive these places are, with a myriad of organisms moving about.

Marsh birds are adept at hiding in dense grasses, so it’s more common to hear them than to see them. That’s why we use a process known as a callback survey to monitor for them.

First we play a prerecorded set of calls to elicit responses from birds in the marsh. Then we determine where we think the birds are calling from and visually estimate the distance from the observer to that spot, often using tools such as laser range finders. We also note the type of ecosystem where we detect the birds – for example, whether they’re in a tidal marsh with emergent vegetation or out in the open on mud flats.

Adult clapper rail calling.

Through this process we’ve been able to estimate the distributions of several species in tidal marshes, including clapper rails, least bitterns (Ixobrychus exilis) and seaside sparrows (Ammospiza maritima). We’ve also plotted trends in their abundance and identified how their numbers can change with characteristics of the marsh.

We’ve walked hundreds of miles through marshes to locate nests and to record data such as nest height, density of surrounding vegetation and proximity to standing water, which provides increased foraging opportunities for rails. Then we revisit the nests to document whether they produce young that hatch and eventually leave. Success isn’t guaranteed: Predators may eat the eggs, or flooding could wash them out of the nest and kill the developing embryos inside.

Salt marshes shelter many types of plants, birds, animals, fish and shellfish.

Rails in the grass

Our research currently focuses on clapper rails, which look like slender chickens with grayish-brown feathers and short tails. Like many other marsh birds, they have longish legs and toes for walking across soft mud, and long bills for probing the marsh surface in search of food. They are found year-round along the Atlantic and Gulf coasts.

Clapper rails typically live in tidal marshes where there is vegetation to hide in and plenty of fiddler crabs, among their frequent foods. Because they are generally common and rely on coastal marshes, they are a good indicator of the health of these coastal areas.

Scientist in marsh holding live Clapper Rail
Ecologist Scott Rush with clapper rail, Pascagoula River Marshes, Mississippi.
Mark Woodrey, CC BY-ND

Water levels in tidal marshes change daily, and clapper rails have some adaptations that help them thrive there. They often build nests in areas with particularly tall vegetation to hide them from predators. And they can raise the height of the nest bowl to protect it against flooding during extra-high or “king” tides and storms. The embryos inside their eggs can survive even if the eggs are submerged for several hours.

When a tropical storm strikes, many factors – including wind speed, flooding and the storm’s position – influence how severely it will affect marsh birds. Typically birds ride out storms by moving to higher areas of the marsh. However, if a storm generates extensive flooding, birds in affected areas may swim or be blown to other locations. We saw this in early June when Hurricane Cristobal blew hundreds of clapper rails onto beaches in parts of coastal Mississippi.

Clapper rails hiding under a breakwater
Clapper rails on a Mississippi beach after Hurricane Cristobal in June 2020.
Mark Woodrey, CC BY-ND

In coastal areas immediately to the east of the eye of a tropical cyclone we typically see a drop in clapper rail populations in the following spring and summer. This happens because the counterclockwise rotation of the storms results in the highest winds and storm surge to the north and east of the eye of the storm.

But typically there’s a strong bout of breeding and a population rebound within a year or so – evidence that these birds are quick to adapt. After Hurricane Katrina devastated the Mississippi Gulf Coast in 2005, however, depending on the type of marsh, it took several years for rail populations to return to their pre-Katrina levels.

Now we’re radio-tagging clapper rails and collecting data that allow us to determine the birds’ life spans. This information helps us estimate when large numbers of birds have died – information that we can correlate with events like coastal hurricanes.

2020 Atlantic hurricane paths
Summary map of the 2020 Atlantic hurricane season, updated Oct. 27.
Master0Garfield/Wikipedia

Losing parts

Tropical storms have shaped coastal ecosystems since long before recorded history. But over the past 150 years humans have complicated the picture. Coastal development – draining marshes, building roads and reinforcing shorelines – is altering natural places that support marsh birds.

Clapper rails and other species have evolved traits that help them offset population losses due to natural disasters. But they can do so only if the ecosystems where they live keep providing them with food, breeding habitat and protection from predators. Coastal development, in combination with rising sea levels and larger tropical storms, can act like a one-two punch, making it increasingly hard for marshes and the species that live in them to recover.

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Biologist Paul Ehrlich has compared species at risk to rivets on an airplane. You might not need every rivet in place for the airplane to fly, but would you fly it through a cyclone if you knew that 10% of its rivets were missing? What about 20%, or 30%? At some point, Ehrlich asserts, nature could lose so many species that it becomes unable to provide valuable services that humans take for granted.

We see coastal marshes as an airplane that humans are piloting through storms. As species and ecosystem services are pummeled, rivets are failing. No one knows where or how the aircraft will land. But we believe that preserving marshes instead of weakening them can improve the chance of a smooth landing.The Conversation

Scott Rush, Assistant Professor of Wildlife Ecology and Management, Mississippi State University and Mark Woodrey, Assistant Research Professor, Mississippi State University

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

Hard to spot, but worth looking out for: 8 surprising tawny frogmouth facts



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Les Christidis, Southern Cross University

The tawny frogmouth is one of Australia’s most-loved birds. In fact, it was first runner-up in the Guardian/BirdLife Australia bird of the year poll (behind the endangered black-throated finch).

Tawny frogmouths are found throughout Australia, including cities and towns, and population numbers are healthy. We’re now in the breeding season – which runs from August to December – so you may have been lucky enough to see some pairs with chicks recently.

Here are eight fascinating things about tawny frogmouths that you might not know.

A Tawny Frogmouth and its chick.
You might have been lucky enough to see a tawny frogmouth chick recently.
Carol Smith, Author provided



Read more:
What Australian birds can teach us about choosing a partner and making it last


1. They are excellent parents

Tawny frogmouths are excellent parents. Both males and females share in building the nest and incubating the eggs, generally one to three. The eggs take 30 days to hatch, with the male incubating during the day and both sexes taking turns during the night.

Once hatched, both parents are very involved in feeding the fledglings. A young bird’s wings take about 25 to 35 days to develop enough strength for flight (a process known as “fledging”).

2. They mate for life

Tawny frogmouths pair for life. Breeding pairs spend a great deal of time roosting together and the male often gently strokes the female with his beak. Some researchers report seeing tawny frogmouths appear to “grieve” when their partner dies.

For example, renowned bird behaviour expert Gisela Kaplan tells of rearing a male tawny frogmouth on her property then releasing it to the wild. It found a female mate and raised nestlings. One day, the female was run over on the highway; Kaplan recognised its markings.

She found the male “whimpering” on a nearby post. Kaplan reportedly said: “It sounds like a baby crying. It affects you to listen to it.” According to Kaplan, the male stayed there for four days and nights, and did not eat or drink.

A pair of Tawny Frogmouths in a tree.
Breeding pairs spend a great deal of time roosting together.
Shutterstock

3. They’re not owls

Although tawny frogmouths are often referred to as owls, they are not. But they do resemble owls with their large eyes, soft plumage and camouflage patterns, because both owls and frogmouths hunt at night. This phenomenon (where two species develop the same attributes, despite not being closely related) is called “convergent evolution”.

Unlike owls, tawny frogmouths do not have powerful feet and talons with which to capture prey. Instead, they prefer to catch prey with their beaks. Their soft, wide, forward-facing beaks are designed for catching insects. They will also feed on small birds, mammals and reptiles.

4. They are masters of disguise

Tawny frogmouths are extremely well camouflaged and when staying statue-still on a tree branch they appear to be part of the tree itself. They often choose to perch near a broken tree branch and thrust their head at angle, further mimicking a tree branch.

A tawny frogmouth sits still on a branch.
Tawny frogmouths are extremely well camouflaged and when staying statue-still on a tree branch they appear to be part of the tree itself.
Shutterstock

5. They make strange noises

Tawny frogmouths are quite vocal at night and have a range of calls from deep grunting to soft “wooing”. When threatened, they make a loud hissing sound. Their vocalisations have also variously been described as purring, screaming and crying.

6. They can survive extremes

In colder regions of Australia, tawny frogmouths are able to survive the winter months by going into torpor for a few hours. In this state, an animal slows its heart rate and metabolism and lowers its body temperature to conserve energy.

On very hot summer days tawny frogmouths will produce mucus in their mouths which cools the air they breathe in, thereby cooling their whole body.

7. They need old trees

It’s not that uncommon to see tawny frogmouths dead on the road; they often flit across the road chasing insects at night and can be hit by cars.

Tawny frogmouth populations are holding relatively steady, but there is a shortage of old trees for nesting. They especially like trees with old branches as they mimic old branches and stick out like sore thumbs on young branches.

When one NSW council chopped down a suburban tree that a tawny frogmouth pair had reportedly used for years as a nesting site, one of the birds was photographed sitting on a nearby woodchipper — a poignant image.

8. They’re not good at building nests.

Tawny frogmouths are pretty slack when it comes to nest building. They simply dump twigs and leaves in a pile and that is it. Chicks and eggs have even fallen out of the nest when parents are swapping brooding duties.

Three tawny frogmouths in a tree
Tawny frogmouths especially like trees with old branches.
Shutterstock



Read more:
Laughs, cries and deception: birds’ emotional lives are just as complicated as ours


The Conversation


Les Christidis, Professor, Southern Cross University

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

New research shows lyrebirds move more litter and soil than any other digging animal



Male Superb Lyrebird in display.
Alex Maisey, Author provided

Alex Maisey, La Trobe University and Andrew Bennett, La Trobe University

When you think of lyrebirds, what comes to mind may be the sound of camera clicks, chainsaws and the songs of other birds. While the mimicry of lyrebirds is remarkable, it is not the only striking feature of this species.

In research just published, we document the extraordinary changes that lyrebirds make to the ground layer in forests in their role as an ecosystem engineer.

Ecosystem engineers change the environment in ways that impact on other species. Without lyrebirds, eastern Australia’s forests would be vastly different places.

Male lyrebird in full tail display.
Alex Maisey

What is an ecosystem engineer?

Ecosystem engineers exist in many environments. By disturbing the soil, they create new habitats or alter existing habitats, in ways that affect other organisms, such as plants and fungi.

A well-known example is the beaver, in North America, which uses logs and mud to dam a stream and create a deep pond. In doing so, it changes the aquatic habitat for many species, including frogs, herons, fish and aquatic plants. Other examples include bandicoots and bettongs.

The Superb Lyrebird acts as an ecosystem engineer by its displacement of leaf litter and soil when foraging for food. Lyrebirds use their powerful claws to rake the forest floor, exposing bare earth and mixing and burying litter, while seeking invertebrate prey such as worms, centipedes and spiders.




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To study the role of the lyrebird as an engineer, we carried out a two-year experiment in Victoria’s Central Highlands, with three experimental treatments.

First, a fenced treatment, where lyrebirds were excluded from fenced square plots measuring 3m wide.

Second, an identical fenced plot but in which we simulated lyrebird foraging with a three-pronged hand rake (about the width of a lyrebird’s foot). This mimicked soil disturbance by lyrebirds but without the birds eating the invertebrates that lived there.

The third treatment was an unfenced, open plot (of the same size) in which wild lyrebirds were free to forage as they pleased.

Over a two-year period, we tracked changes in the litter and soil, and measured the amount of soil displaced inside and outside of these plots.

A colour-banded female lyrebird in Sherbrooke Forest, Victoria. Her powerful claws are used for foraging in litter and soil.
Meghan Lindsay

Lyrebirds dig up a lot of dirt

On average, foraging by wild lyrebirds resulted in a staggering 155 tonnes per hectare of litter and soil displaced each year throughout these forests.

To the best of our knowledge, this is more than any other digging vertebrate, worldwide.

To put this in context, most digging vertebrates around the world, such as pocket gophers, moles, bandicoots and bettongs, displace between 10-20 tonnes of material per hectare, per year.

To picture what 155 tonnes of soil looks like, imagine the load carried by five medium-sized 30 tonne dump trucks – and this is just for one hectare!

But how much does an individual lyrebird displace? At one study location we estimated the density of the lyrebird population to be approximately one lyrebird for every 2.3 hectares of forest, thanks to the work of citizen scientists led by the Sherbrooke Lyrebird Study Group.

Based on this estimate, and to use our dump truck analogy, a single lyrebird will displace approximately 11 dump trucks of litter and soil in a single year.

Lyrebirds dig up a lot of dirt in forests.

Changes to the ground layer

After two years of lyrebird exclusion, leaf litter in the fenced plots was approximately three times deeper than in the unfenced plots. Soil compaction was also greater in the fenced plots.

Where lyrebirds foraged, the soil easily crumbled and the litter layer never fully recovered to a lyrebird-free state before foraging re-occurred.

This dynamic process of disturbance by lyrebirds has been going on for millennia, profoundly shaping these forests. For organisms such as centipedes, spiders and worms living in the litter and soil, the forest floor under the influence of lyrebirds may provide new opportunities that would not exist in their absence.

Terraced soil where litter has been removed and roots exposed by foraging lyrebirds.
Alex Maisey

An ecosystem ravaged by fire

The Australian megafires of 2019/20 resulted in approximately 40% of the Superb Lyrebird’s entire distribution being incinerated, according to a preliminary analysis by BirdLife Australia.

So great was the extent of these fires that the conservation status of the lyrebird has been thrown into question. That the conservation status has fallen – from “common” to potentially being “threatened” – from a single event is deeply concerning.




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


Loss of lyrebird populations on this scale will have potentially far-reaching effects on forest ecology.

In the face of climate change and a heightened risk of severe wildfire, understanding the role that species such as the Superb Lyrebird play in ecosystems is more important than ever.

Without lyrebirds, eastern Australia’s forests would be vastly different places, with impacts extending well beyond the absence of their glorious song to other animals who rely on these “ecosystem engineers”.The Conversation

Alex Maisey, PhD Candidate, La Trobe University and Andrew Bennett, Professor of Ecology, La Trobe University

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

What ‘The Birdman of Wahroonga’ and other historic birdwatchers can teach us about cherishing wildlife



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Russell McGregor, James Cook University

Under the first coronavirus lockdowns, birdwatching increased tenfold in Australia, with much of it done in and near the watchers’ own backyards. And as Melbourne settles into stage 4 restrictions, we’ll likely see this rise again.

The increase in backyard birding is good news for conservation and can help birds recover from bushfires and other environmental catastrophes. But backyard birding isn’t new, nor is its alliance with conservation.




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Birdwatching increased tenfold last lockdown. Don’t stop, it’s a huge help for bushfire recovery


Since the turn of the 20th century, when birdwatching as a hobby began in Australia, birders have cherished the birds in their backyards as much as those in outback wilds. Birdwatchers admired wild birds anywhere, for one of their big motivations was — and is — to experience and conserve the wild near home.

Harry Wolstenholme holding a bird in front of him in his garden in Sydney
Pioneering birder Harry Wolstenholme recorded 21 native species nesting in his garden.
Alec Chisholm/National Library of Australia, Author provided

This wasn’t an abstract ambition, but a heartfelt commitment. Birdwatchers have long known that if we are to conserve nature, we need not only the intellectual expertise of science but also an emotional affinity with the living things around us. Birders in Sydney in the 1920s and ‘30s knew this well.

The Birdman of Wahroonga

Harry Wolstenholme, son of the feminist Maybanke Anderson, was an office-bearer in the Royal Australasian Ornithologists’ Union and a keen amateur birdwatcher. In the 1920s, his usual birding site was his own garden in the northern Sydney suburb of Wahroonga.

There, bird life was prolific. Harry recorded 21 native and five introduced species nesting in or near his garden, plus many more avian visitors.

His garden drew a stream of notable birders from the Sydney branch of the ornithologists’ union, such as wildlife photographer Norman Chaffer, naturalist and journalist Alec Chisholm, and businessman Keith Hindwood. (The union members were predominantly male, though with a liberal sprinkling of women, including Perrine Moncrieff who became its first female president in 1932.)

Keith Hindwood in black and white, with a White-eared Honeyeater on his head
Keith Hindwood, with a White-eared Honeyeater on his head, 1929.
Mitchell Library, Author provided

For his closeness to the birds, Harry earned the nickname “The Birdman of Wahroonga”. That suburb still hosts a good range of species, although the bird life is no longer as prolific as in Harry’s day.

Many others birded in city environs and, like Harry, published their suburban ornithological studies in the union journal, The Emu.

In 1932, Alec Chisholm devoted a whole book, Nature Fantasy in Australia, to birding in Sydney and surrounds. Featured on its early pages is a painting by celebrated bird artist Neville Cayley captioned “The Spirit of Sydney: Scarlet Honeyeater at nest in suburban garden”.

Scarlet honeyeater feeding on grevillia nectar
Scarlet honeyeaters can still be spotted in urban parts of Australia.
Shutterstock

The fact this gorgeous little bird was common in Sydney’s gardens exemplifies Chisholm’s theme of urban Australians’ ready access to the wonders of nature. Scarlet Honeyeaters can still be found in Sydney though they are no longer common there.

Mateship with Birds

Like all Chisholm’s nature writings, Nature Fantasy promoted conservation.

Conservation then differed from conservation now, having a stronger aesthetic orientation and less ecological content. Nonetheless, these pioneer conservationists, among whom birdwatchers were prominent, laid the foundations on which environmentalists later built.

Chisholm urged people not merely to observe birds but also, more importantly, to love and cherish them. In his first book in 1922, Mateship with Birds, he urged readers to open their hearts to their avian compatriots and embrace them as friends and fellow Australians.

Jacky winter, a small, pale-coloured bird is perched on a white log.
Early birders believed names of birds like ‘Jacky Winter’ would help us embrace birds as fellow Australians.
Shutterstock

One way of fostering this feeling, Chisholm and his birding contemporaries believed, was to give birds attractive names. For example, “Jacky Winter” struck the right note, and as Chisholm wrote:

it would be a healthy thing if we had more of these familiar names for our birds, bringing as they do, a feeling or sense of intimacy.

While those birders urged people to cultivate an emotional connection with nature, and while most were amateur rather than professional ornithologists, they nonetheless made major contributions to the scientific study of birds.

Science was needed, they realised, but so was feeling. As one reviewer of Nature Fantasy enthused, Chisholm was a naturalist “who in his writings combines with the exact research of a scientist the sensibility of a poet”.




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Birders today

Our city birdscapes have since changed. Some species have dwindled; some have increased. But suburbia still holds a remarkable degree of biodiversity, if only we’re prepared to look.

A woman holds binoculars to her eyes among trees
Lockdown is a great time to try backyard birdwatching.
Shutterstock

The world of the birders of the 1920s and ’30s is gone. Our attitudes toward nature are cluttered with fears unknown in their day, such as climate change. Yet those early birders still have something worthwhile to tell us today: the need to connect emotionally and tangibly with nature.

To hear that message, we need not, and should not, jettison today’s environmental fears. But fear needs complementing with more positive emotions, like love.

Despite — or because of — the prominence of environmental alarms in today’s world, the need to admire and love living things remains as pressing as ever. As birdwatchers have long known, the birds fluttering in our own backyards are adept at fostering those feelings.




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


The Conversation


Russell McGregor, Adjunct Professor of History, James Cook University

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

Click through the tragic stories of 119 species still struggling after Black Summer in this interactive (and how to help)



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Anthea Batsakis, The Conversation and Wes Mountain, The Conversation

This article is part of Flora, Fauna, Fire, a special project by The Conversation that tracks the recovery of Australia’s native plants and animals after last summer’s bushfire tragedy. Explore the project here and read more articles here.


Before the summer bushfires destroyed vast expanses of habitat, Australia was already in the midst of a biodiversity crisis. Now, some threatened species have been reduced to a handful of individuals – and extinctions are a real possibility.

The Kangaroo Island dunnart, a small marsupial, was listed as critically endangered before the bushfires. Then the inferno destroyed 95% of its habitat.

Prospects for the Banksia Montana mealybug are similarly grim. This flightless insect lives only on one species of critically endangered plant, at a high altitude national park in Western Australia. The fires destroyed 100% of the plant’s habitat.




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And fewer than 100 western ground parrots remained in the wild before last summer, on Western Australia’s south coast. Last summer’s fires destroyed 40% of its habitat.

Fish, crayfish and some frogs are also struggling. After the fires, heavy rain washed ash, fire retardants and dirt into waterways. This can clog and damage gills, and reduces the water’s oxygen levels. Some animals are thought to have suffocated.

Here, dozens of experts tell the stories of the 119 species most in need of help after our Black Summer.

How can I help?

Recovery from Australia’s bushfire catastrophe will be a long road. If you want to help, here are a few places to start.

Donate

Australian Wildlife Conservancy

Bush Heritage Australia

WWF

Birdlife Australia

Also see this list of registered bushfire charities

Volunteer

Parks Victoria

NSW National Parks and Wildlife Service

Queensland Parks and Wildlife Service

Conservation Volunteers Australia

Landcare

The Conversation

Anthea Batsakis, Deputy Editor: Environment + Energy, The Conversation and Wes Mountain, Multimedia Editor, The Conversation

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

Our helicopter rescue may seem a lot of effort for a plain little bird, but it was worth it



John Harrison/WIkimedia

Rohan Clarke, Monash University; Katherine Selwood, University of Melbourne, and Rowan Mott, Monash University

This article is part of Flora, Fauna, Fire, a special project by The Conversation that tracks the recovery of Australia’s native plants and animals after last summer’s bushfire tragedy. Explore the project here and read more articles here.


As we stepped out of a military helicopter on Victoria’s east coast in February, smoke towered into the sky. We’d just flown over a blackened landscape extending as far as the eye could see. Now we were standing in an active fireground, and the stakes were high.

Emergency helicopter rescues aren’t usually part of a day’s work for conservation scientists. But for eastern bristlebirds, a potential disaster loomed.

Our mission was to catch 15-20 bristlebirds and evacuate them to Melbourne Zoo. This would provide an insurance population of this globally endangered species if their habitat was razed by the approaching fire.

As climate change grows ever worse, such rescues will be more common. Ours showed how it can be done.

A Chinook helicopter, with the bristlebird field team on board, lands in far eastern Victoria.
Tony Mitchell

The plight of the eastern bristlebird

Such a rescue may seem like a lot of effort for a small, plain brown bird. But eastern bristlebirds are important to Australia’s biodiversity.

They continue an ancient lineage of songbirds that dates back to the Gondwanan supercontinent millions of years ago. They’re reminders of wild places that used to exist, unchanged by humans.




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These days, coastal development has shrunk the eastern bristlebird’s habitat. The birds are feeble flyers, and so populations die out when their habitat patches become too small.

Fewer than 2,500 individuals remain, spread across three locations on Australia’s east coast including a 400-strong population that straddles the Victoria-New South Wales border at Cape Howe. Losing them would be a huge blow to the species’ long term prospects.

One of 15 eastern bristlebirds caught and evacuated from Cape Howe.
Author provided

A rollercoaster ride

On the day of our rescue, bushfires had been raging on Australia’s east coast for several months. The so-called Snowy complex fire that started in late December had razed parts of Mallacoota on New Year’s Eve then burnt into NSW. Now, more than a month later, that same fire had crossed back over the state border and was burning into Cape Howe.

Our 11-person field team had two chances over consecutive mornings. Using special nets, we caught nine eastern bristlebirds on one morning, and six the next. As we worked, burnt leaves caught in our nets – a tangible reminder of how close the fire was.

The captured birds were health-checked then whisked – first by 4WD, then boat and car – to a waiting flight to Melbourne. From there they were driven to special enclosures at Melbourne Zoo.

On the second day a wind change intensified the bushfire and cut short our time. As we evacuated under a darkening sky, it seemed unlikely Cape Howe would escape the flames.

A box containing eastern bristlebirds about to be loaded onto a boat.

In the ensuing days, the fire moved agonisingly close to the site until a favourable wind change spared it.

But tragedy struck days later when fire tore through eastern bristlebird habitat on the NSW side of Cape Howe. Many of the 250 individuals that lived there are presumed dead.

And despite the best efforts of vets and expert keepers at Melbourne Zoo, six of our captive birds succumbed to a fungal respiratory infection in the weeks after their arrival, which they were all likely carrying when captured.

Return to Cape Howe

Against the odds, bristlebird habitat on the Victorian side of Cape Howe remained unburnt. So in early April, we released a little flock of seven back into the wild.

We’d initially planned to attach tiny transmitters to some released bristlebirds to monitor how they settled back into their home. But COVID-19 restrictions forced us to cancel this intensive fieldwork.

Instead, each bristlebird was fitted with a uniquely coloured leg band. As restrictions ease, our team will return to Cape Howe to see how the colour-banded birds have fared.

Eastern bristlebirds released back into the wild at Howe Flat.
Darryl Whitaker/DELWP

A model for the future

The evacuation involved collaboration between government agencies and non-government organisations, with especially important coordination and oversight by Zoos Victoria, the Victorian Department of Environment, Land, Water and Planning, and Parks Victoria.

This team moved mountains of logistical hurdles. A rescue mission that would ordinarily take more than a year to plan was completed in weeks.




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So was it all worth it? We strongly believe the answer is yes. The team did what was needed for the worst-case scenario; ultimately that scenario was avoided by a mere whisker.

But climate change is heightening fire danger and increasing the frequency of extreme weather events. Soberingly, further emergency wildlife evacuations will probably be needed to prevent extinctions in future. Our mission will serve as a model for these interventions.

The Conversation

Rohan Clarke, Director, Monash Drone Discovery Platform, and Senior Lecturer in Ecology, Monash University; Katherine Selwood, Threatened Species Biologist, Wildlife Conservation & Science, Zoos Victoria and Honorary Research Fellow, Biosciences, University of Melbourne, and Rowan Mott, Biologist, Monash University

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

Birdwatching increased tenfold last lockdown. Don’t stop, it’s a huge help for bushfire recovery



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Ayesha Tulloch, University of Sydney; April Reside, The University of Queensland; Georgia Garrard, RMIT University; Michelle Ward, The University of Queensland, and Monica Awasthy, Griffith University

Many Victorians returning to stage three lockdown will be looking for ways to pass the hours at home. And some will be turning to birdwatching.

When Australians first went into lockdown in March, the combination of border closures, lockdowns and the closure of burnt areas from last summer’s bushfires meant those who would have travelled far and wide to watch their favourite birds, instead stayed home.

Yet, Australians are reporting bird sightings at record rates – they’ve just changed where and how they do it.

In fact, Australian citizen scientists submitted ten times the number of backyard bird surveys to BirdLife Australia’s Birdata app in April compared with the same time last year, according to BirdLife Australia’s Dr Holly Parsons.

But it’s not just a joyful hobby. Australia’s growing fascination with birds is vital for conservation after last summer’s devastating bushfires reduced many habitats to ash.

Birds threatened with extinction

Australia’s native plants and animals are on the slow path to recovery after the devastating fires last summer. In our research that’s soon to be published, we found the fires razed forests, grasslands and woodlands considered habitat for 832 species of native vertebrate fauna. Of these, 45% are birds.

Some birds with the largest areas of burnt habitat are threatened with extinction, such as the southern rufous scrub-bird and the Kangaroo Island glossy black-cockatoo.

Government agencies and conservation NGOs are rolling out critical recovery actions.

But citizen scientists play an important role in recovery too, in the form of monitoring. This provides important data to inform biodiversity disaster research and management.

Record rates of birdwatching

Birdwatchers have recorded numerous iconic birds affected by the fires while observing COVID-19 restrictions. They’ve been recorded in urban parks and city edges, as well as in gardens and on farms.

In April 2020, survey numbers in BirdLife Australia’s Birds in Backyards program jumped to 2,242 – a tenfold increase from 241 in April 2019.

Change in the number of area-based surveys by Australian citizen scientists over the first six months of 2019 compared with 2020. Data sourced from BirdLife Australia’s Birdata database.

Similarly, reporting of iconic birds impacted by the recent bushfires has increased.

Between January and June, photos and records of gang-gang cockatoos in the global amateur citizen science app iNaturalist increased by 60% from 2019 to 2020. And the number of different people submitting these records doubled from 26 in 2019 to 53 in 2020.




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Want to help save wildlife after the fires? You can do it in your own backyard


What’s more, reporting of gang-gangs almost doubled in birding-focused apps, such as Birdlife Australia’s Birdata, which recently added a bushfire assessment tool .

The huge rise in birdwatching at home has even given rise to new hashtags you can follow, such as #BirdingatHome on Twitter, and #CuppaWithTheBirds on Instagram.

A gang-gang effort: why we’re desperate for citizen scientists

The increased reporting rates of fire-affected birds is good news, as it means many birds are surviving despite losing their home. But they’re not out of the woods yet.

Their presence in marginal habitats within and at the edge of urban and severely burnt areas puts them more at risk. This includes threats from domestic cat and dog predation, starvation due to inadequate food supply, and stress-induced nest failure.

That’s why consolidating positive behaviour change, such as the rise in public engagement with birdwatching and reporting, is so important.

A female superb lyrebird calling to her reflection in a parked car in suburbia. Her nest was later discovered 100 meters from the carpark.

Citizen science programs help increase environmental awareness and concern. They also improve the data used to inform conservation management decisions, and inform biodiversity disaster management.

For example, improved knowledge about where birds go after fire destroys their preferred habitat will help conservation groups and state governments prioritise locations for recovery efforts. Such efforts include control of invasive predators, supplementary feeding and installation of nest boxes.

Gang gang Cockatoo hanging out on a street sign in Canberra.
Athena Georgiou/Birdlife Photography

Better understanding of how bushfire-affected birds use urban and peri-urban habitats will help governments with long-term planning that identifies and protects critical refuges from being cleared or degraded.

And new data on where birds retreat to after fires is invaluable for helping us understand and plan for future bushfire emergencies.

So what can you do to help?

If you have submitted a bird sighting or survey during lockdown, keep at it! If you have never done a bird survey before, but you see one of the priority birds earmarked for special recovery efforts, please report them.




Read more:
Six million hectares of threatened species habitat up in smoke


There are several tools available to the public for reporting and learning about birds.

iNaturalist asks you to share a photo or video or sound recording, and a community of experts identifies it for you.

BirdLife’s Birds in Backyards program includes a “Bird Finder” tool to help novice birders identify that bird sitting on the back verandah. Once you’ve figured out what you’re seeing, you can log your bird sightings to help out research and management.

The majority of habitat for Kangaroo Island glossy black cockatoos burnt last summer.
Bowerbirdaus/Wikimedia, CC BY-SA

For more advanced birders who can identify birds without guidance, options include eBird and BirdLife’s Birdata app. This will help direct conservation groups to places where help is most needed.

Finally, if there are fire-affected birds, such as lyrebirds and gang-gang cockatoos, in your area, it’s especially important to keep domestic dogs and cats indoors, and encourage neighbours to do the same. Report fox sightings to your local council.




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Lots of people want to help nature after the bushfires – we must seize the moment


If you come across a bird that’s injured or in distress, it’s best to contact a wildlife rescue organisation, such as Wildcare Australia (south-east Queensland), WIRES (NSW) or Wildlife Victoria.

By ensuring their homes are safe and by building a better bank of knowledge about where they seek refuge in times of need, we can all help Australia’s unique wildlife.The Conversation

Ayesha Tulloch, DECRA Research Fellow, University of Sydney; April Reside, Researcher, Centre for Biodiversity and Conservation Science, The University of Queensland; Georgia Garrard, Senior Research Fellow, Interdisciplinary Conservation Science Research Group, RMIT University; Michelle Ward, PhD Candidate, The University of Queensland, and Monica Awasthy, Visiting Research Scientist, Environmental Futures Research Institute, Griffith University

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