We name the 26 Australian frogs at greatest risk of extinction by 2040 — and how to save them

Spotted tree frog.
Michael Williams/Its A Wildlife Photography, Author provided

Graeme Gillespie, The University of Melbourne; Conrad Hoskin, James Cook University; Hayley Geyle, Charles Darwin University; Jaana Dielenberg, Charles Darwin University; Nicola Mitchell, The University of Western Australia, and Stephen Garnett, Charles Darwin UniversityAustralia is home to more than 240 frog species, most of which occur nowhere else. Unfortunately, some frogs are beyond help, with four Australian species officially listed as extinct.

This includes two remarkable species of gastric-brooding frog. To reproduce, gastric-brooding frogs swallowed their fertilised eggs, and later regurgitated tiny baby frogs. Their reproduction was unique in the animal kingdom, and now they are gone.

Our new study published today, identified the 26 Australian frogs at greatest risk, the likelihood of their extinctions by 2040 and the steps needed to save them.

Tragically, we have identified an additional three frog species that are very likely to be extinct. Another four species on our list are still surviving, but not likely to make it to 2040 without help.

#1 The northern gastric-brooding frog (Rheobatrachus vitellinus) is likely already extinct, primarily due to chytrid fungus disease.
Hal Cogger

The 26 most imperilled frogs

The striking yellow-spotted tree frog (in southeast Australia), the northern tinker frog and the mountain mist frog (both in Far North Queensland) are not yet officially listed as extinct – but are very likely to be so. We estimated there is a greater than 90% chance they are already extinct.

The locations of the top 26 Australian frogs at risk of extinction. ** Species likely to be recently extinct. * Species more likely than not to become extinct by 2040 unless there is action.
Jaana Dielenberg/Threatened Species Recovery Hub

The next four most imperilled species are hanging on in the wild by their little frog fingers: the southern corroboree frog and Baw Baw frog in the Australian Alps, and the Kroombit tinker frog and armoured mist frog in Queensland’s rainforests.

The southern corroboree frog, for example, was formerly found throughout Kosciuszko National Park in the Snowy Mountains. But today, there’s only one small wild population known to exist, due largely to an introduced disease.

Without action it is more likely than not (66% chance) the southern corroboree frog will become extinct by 2040.

#6 The southern corroboree frog (Pseudophryne corroboree) is close to extinction.
David Hunter/DPIE NSW

#3 The yellow-spotted tree frog (Litoria castanea) is likely extinct. It was once common throughout the New England Tableland and Southern Tablelands region in NSW, and the ACT. It is sensitive to chytrid fungus disease and also impacted by climate change, habitat loss and invasive fish.
David Hunter/DPIE NSW

What are we up against?

Species are suffering from a range of threats. But for our most recent extinctions and those now at greatest risk, the biggest cause of declines is the amphibian chytrid fungus disease.

This introduced fungus is thought to have arrived in Australia in the 1970s and has taken a heavy toll on susceptible species ever since. Cool wet environments, such as rainforest-topped mountains in Queensland where frog diversity is particularly high, favour the pathogen.

The fungus feeds on the keratin in frogs’ skin — a major organ that plays a vital role in regulating moisture, exchanging respiratory gases, immunity, and producing sunscreen-like substances and chemicals to deter predators.

Chrytrid disease killed this green-eyed tree frog.
Robert Puschendorf

#8 Armoured mist frog (Litoria lorica) populations have been decimated by chytrid fungus disease. It has been lost throughout former mountainous rainforest habitats where the fungus thrives. Without effective action, it’s likely to be extinct within 20 years.
Conrad Hoskin

Another major emerging threat is climate change, which heats and dries out moist habitats. It’s affecting 19 of the imperilled species we identified, such as the white-bellied frog in Western Australia, which develops tadpoles in little depressions in waterlogged soil.

Climate change is also increasing the frequency, extent and intensity of fires, which have impacted half (13) of the identified species in recent years. The Black Summer fires ravaged swathes of habitat where fires should rarely occur, such as mossy alpine wetlands inhabited by the northern corroboree frog.

Invasive species impact ten frog species. For the spotted tree frog in southern Australia, introduced fish such as brown and rainbow trout are the main problem, as they’re aggressive predators of tadpoles. In northern Australia, feral pigs often wreak havoc on delicate habitats.

#15 The Kuranda tree frog (Litoria myola) is found in a very small area near Cairns. Its primary threat is loss and degradation of habitat due to development.
Conrad Hoskin

#20 The white-bellied frog (Geocrinia alba) is the Western Australian frog at greatest risk of extinction. The tadpoles of this tiny terrestrial breeding frog rely on wet soil to develop. Reduced rainfall is contributing to declines.
Emily Hoffmann

So what can we do about it?

We identified the key actions that can feasibly be implemented in time to save these species. This includes finding potential refuge sites from chytrid and from climate change, reducing bushfire risks and reducing impacts of introduced species.

But for many species, these actions alone aren’t enough. Given the perilous state of some species in the wild, captive conservation breeding programs are also needed. But they cannot be the end goal.

#11 A northern corroboree frog in the captive breeding program run by the ACT Government.
Peter Taylor/Threatened Species Recovery Hub

Captive breeding programs can not only establish insurance populations, they can also help a species persist in the wild by supplying frogs to establish populations at new suitable sites.

Boosting numbers in existing wild populations with captive bred frogs improves their chance of survival. Not only are there more frogs, but also greater genetic diversity. This means the frogs have a better chance of adapting to new conditions, including climate change and emerging diseases.

Our knowledge of how to breed frogs in captivity has improved dramatically in recent decades, but we need to invest in doing this for more frog species.

Please save these frogs: The 26 Australian species at greatest risk of extinction.

Finding and creating wild refuges

Another vital way to help threatened frogs persist in the wild is by protecting, creating and expanding natural refuge areas. Refuges are places where major threats are eliminated or reduced enough to allow a population to survive long term.

For the spotted-tree frog, work is underway to prevent the destruction of frog breeding habitat by deer, and to prevent tadpoles being eaten by introduced predatory fish species. These actions will also help many other frog species as well.

The chytrid fungus can’t be controlled, but fortunately it does not thrive in all environments. For example, in the warmer parts of species’ range, pathogen virulence may be lower and frog resilience may be higher.

Chytrid fungus completely wiped out the armoured mist frog from its cool, wet heartland in the uplands of the Daintree Rainforest. But, a small population was found surviving at a warmer, more open site where the chytrid fungus is less virulent. Conservation for this species now focuses on these warmer sites.

This strategy is now being used to identify potential refuges from chytrid for other frog species, such as the northern corroboree frog.

Dr Graeme Gillespie during a survey for the spotted-tree frog.
Michael Williams/Its A Wildlife Photography

No time to lose

We missed the window to save the gastric-brooding frogs, but we should heed their cautionary tale. We are on the cusp of losing many more unique species.

Decline can happen so rapidly that, for many species, there is no time to lose. Apart from the unknown ecological consequences of their extinctions, the intrinsic value of these frogs means their losses will diminish our natural legacy.

In raising awareness of these species we hope we will spark new action to save them. Unfortunately, despite persisting and evolving independently for millions of years, some species can now no longer survive without our help.

Graeme Gillespie, Honorary Research Fellow, The University of Melbourne; Conrad Hoskin, Lecturer/ABRS Postdoctoral Fellow, James Cook University; Hayley Geyle, Research Assistant, Charles Darwin University; Jaana Dielenberg, University Fellow, Charles Darwin University; Nicola Mitchell, Associate Professor in Conservation Physiology, The University of Western Australia, and Stephen Garnett, Professor of Conservation and Sustainable Livelihoods, Charles Darwin University

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

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The 50 beautiful Australian plants at greatest risk of extinction — and how to save them

Caley’s grevillea (Grevillea caleyi) occurs in Sydney. It needs fire to germinate but burns are hard to carry out near urban areas.
Tony Auld, Author provided

Jennifer Silcock, The University of Queensland; Jaana Dielenberg, Charles Darwin University; Roderick John Fensham, The University of Queensland, and Teghan Collingwood, The University of QueenslandAs far as odds go, things don’t look promising for the slender-nerved acacia (Acacia leptoneura), a spiky plant with classic yellow-ball wattle flowers. With most of its habitat in Western Australia’s wheat belt cleared for agriculture, it was considered extinct for more than 160 years.

Now, just two plants are known in the world, and they’re not even in the same place. This species is among many Australian plants that have come perilously close to extinction.

To help prevent the loss of any native plant species, we’ve assembled a massive evidence base for more than 750 plants listed as critically endangered or endangered. Of these, we’ve identified the 50 at greatest risk of extinction.

The good news is for most of these imperilled plants, we already have the knowledge and techniques needed to conserve them. We’ve devised an action plan that’s relatively easy to implement, but requires long-term funding and commitment.

What’s driving the loss?

There are 1,384 plant species and subspecies listed as threatened at a national level. Twelve Australian plant species are considered probably extinct and a further 21 species possibly extinct, while 206 are officially listed as critically endangered.

Two known plants of slender nerved acacia (Acacia leptoneura) remain, about 1 kilometre apart. Propagation attempts have been unsuccessful and the genetic diversity is probably very low.
Joel Collins, Author provided

Australian plants were used, managed and celebrated by Australia’s First Nations people for at least 60,000 years, but since European colonisation, they’ve been beset by a range of threats.

Land clearing, the introduction of alien plants, animals, diseases, and interruptions to ecological processes such as fire patterns and flooding have taken a heavy toll on many species. This is particularly the case in the more densely populated eastern and southern parts of the continent.

Ironstone pixie mop (Petrophile latericola) occurs on a soil type that’s been heavily cleared for agriculture, and is suspected to be susceptible to an introduced root-rot fungus. In 2020 fewer than 200 plants remained, in poor condition.
Andrew Crawford, Author provided

Things aren’t improving. Scientists recently compiled long-term monitoring of more than 100 threatened plant species at 600 sites nationally. And they found populations had declined on average by 72% between 1995 and 2017.

This is a very steep rate of decline, much greater than for threatened mammal or bird populations.

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Read more:
Australia-first research reveals staggering loss of threatened plants over 20 years

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On the brink

Many species listed as threatened aren’t receiving targeted conservation action or even baseline monitoring, so an important first step in preventing extinctions was identifying the species at greatest risk.

To find the top 50, we looked at the evidence: all available published and unpublished information and expert surveys of over 120 botanists and land managers.
They’re targeted by our Action Plan for Australia’s Imperilled Plants.

Action Plan for Australia’s Imperilled Plants.

Thirty of the species in the plan have fewer than 50 mature individual plants remaining.

And 33 are known only from a single location, such as the Grampians pincushion-lily (Borya mirabilis), which occurs on one rocky outcrop in Victoria. This means the entire population could be destroyed by a single event, such as a major bushfire.

About 2,000 Morrisby’s gums were growing in the early 1990s, but by 2016 fewer than 50 remained. Climate change and damage from insects and animals threaten those left. Protecting trees with fencing has led to new seedlings.
Magali Wright, Author provided

Fewer than 10 lax leek-orchids (Prasophyllum laxum) remain. Declines are ongoing due to drought and wildfire, and the South Australian species only occurs on private property not managed for conservation. Proposed recovery actions include habitat protection and establishing the orchid and its mycorrhizal fungi in conservation reserves.
Shane Graves, Author provided

Fewer than 15 woods well spyridium (Spyridium fontis-woodii) shrubs remain on a single roadside in South Australia. Research into threats and germination requirements is urgently needed, plus translocation to conservation reserves.
Daniel Duval/South Australian Seed Conservation Centre, Author provided

So how can we protect them?

Some of the common management actions we’ve proposed include:

• preventing further loss of species’ habitat. This is the most important action required at a national scale
• regularly monitoring populations to better understand how species respond to threats and management actions
• safely trialling appropriate fire management regimes, such as burning in areas where fires have been suppressed
• investing in disease research and management, to combat the threat of phytophthora (root-rot fungus) and myrtle rust, which damages leaves
• propagating and moving species to establish plants at new sites, to boost the size of wild populations, or to increase genetic diversity
• protecting plants from grazing and browsing animals, such as feral goats and rabbits, and sometimes from native animals such as kangaroos.

Once common, the dwarf spider-orchid (Caladenia pumila) wasn’t seen for over 80 years until two individual plants were found. Despite intensive management, no natural recruitment has occurred. Propagation attempts have successfully produced 100 seedlings and 11 mature plants from seed. This photo shows botanist Marc Freestone hand-pollinating dwarf spider-orchids.
Marc Freestone, Author provided

Only 21 mature plants of Gillingarra grevillea (Grevillea sp. Gillingarra) remain on a disturbed, weedy rail reserve in southwestern WA. Half the population was destroyed in 2011 due to railway maintenance and flooding. Habitat protection and restoration, and translocations to conservation reserves are needed to ensure its survival.
Andrew Crawford, Author provided

Another common issue is lack of recruitment, meaning there’s no young plants coming up to replace the old ones when they die. Sometimes this is because the processes that triggered these plants to flower, release seed or germinate are no longer occurring. This can include things like fire of a particular intensity or the right season.

Unfortunately, for some plants we don’t yet know what triggers are required, and further research is essential to establish this.

Now we need the political will

Our plan is for anyone involved in threatened flora management, including federal, state, territory and local government groups, First Nations, environment and community conservation groups, and anyone with one of these plants on their land.

The Border Ranges lined fern (Antrophyum austroqueenslandicum) and its habitat are exceedingly rare. It’s threatened by drought and climate change, and fewer than 50 plants remain in NSW. If the threat of illegal collection can be controlled, the species would benefit from re-introduction to Queensland’s Lamington National Park.
Lui Weber, Author provided

Plants make Australian landscapes unique — over 90% of our plant species are found nowhere else in the world. They’re also the backbone of our ecosystems, creating the rich and varied habitats for our iconic fauna to live in. Plants underpin and enrich our lives every day.

Now we have an effective plan to conserve the Australian plants at the greatest risk of extinction. What’s needed is the political will and resourcing to act in time.

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Read more:
Undocumented plant extinctions are a big problem in Australia – here’s why they go unnoticed

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Jennifer Silcock, Post-doctoral research fellow, The University of Queensland; Jaana Dielenberg, University Fellow, Charles Darwin University; Roderick John Fensham, Associate Professor of Biological Sciences, The University of Queensland, and Teghan Collingwood, Research Technician, The University of Queensland

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

Melbourne’s Water Supply at Risk

We’re all ingesting microplastics at home, and these might be toxic for our health. Here are some tips to reduce your risk

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Mark Patrick Taylor, Macquarie University; Neda Sharifi Soltani, Macquarie University, and Scott P. Wilson, Macquarie UniversityAustralians are eating and inhaling significant numbers of tiny plastics at home, our new research shows.

These “microplastics”, which are derived from petrochemicals extracted from oil and gas products, are settling in dust around the house.

Some of these particles are toxic to humans — they can carry carcinogenic or mutagenic chemicals, meaning they potentially cause cancer and/or damage our DNA.

We still don’t know the true impact of these microplastics on human health. But the good news is, having hard floors, using more natural fibres in clothing, furnishings and homewares, along with vacuuming at least weekly can reduce your exposure.

What are microplastics?

Microplastics are plastic particles less than five millimetres across. They come from a range of household and everyday items such as the clothes we wear, home furnishings, and food and beverage packaging.

We know microplastics are pervasive outdoors, reaching remote and inaccessible locations such as the Arctic, the Mariana Trench (the world’s deepest ocean trench), and the Italian Alps.

Our study demonstrates it’s an inescapable reality that we’re living in a sea of microplastics — they’re in our food and drinks, our oceans, and our homes.

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

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What we did and what we found

While research has focused mainly on microplastics in the natural environment, a handful of studies have looked at how much we’re exposed to indoors.

People spend up to 90% of their time indoors and therefore the greatest risk of exposure to microplastics is in the home.

Our study is the first to examine how much microplastic we’re exposed to in Australian homes. We analysed dust deposited from indoor air in 32 homes across Sydney over a one-month period in 2019.

We asked members of the public to collect dust in specially prepared glass dishes, which we then analysed.

Here’s how microplastics can be generated, suspended, ingested and inhaled inside a house.
Monique Chilton, Author provided

We found 39% of the deposited dust particles were microplastics; 42% were natural fibres such as cotton, hair and wool; and 18% were transformed natural-based fibres such as viscose and cellophane. The remaining 1% were film and fragments consisting of various materials.

Between 22 and 6,169 microfibres were deposited as dust per square metre, each day.

Homes with carpet as the main floor covering had nearly double the number of petrochemical-based fibres (including polyethylene, polyamide and polyacrylic) than homes without carpeted floors.

Conversely, polyvinyl fibres (synthetic fibres made of vinyl chloride) were two times more prevalent in homes without carpet. This is because the coating applied to hard flooring degrades over time, producing polyvinyl fibres in house dust.

Microplastics can be toxic

Microplastics can carry a range of contaminants such as trace metals and some potentially harmful organic chemicals.

These chemicals can leach from the plastic surface once in the body, increasing the potential for toxic effects. Microplastics can have carcinogenic properties, meaning they potentially cause cancer. They can also be mutagenic, meaning they can damage DNA.

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Why ocean pollution is a clear danger to human health

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However, even though some of the microplastics measured in our study are composed of potentially carcinogenic and/or mutagenic compounds, the actual risk to human health is unclear.

Given the pervasiveness of microplastics not only in homes but in food and beverages, the crucial next step in this research area is to establish what, if any, are safe levels of exposure.

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You’re eating microplastics in ways you don’t even realise

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How much are we exposed to? And can this be minimised?

Roughly a quarter of all of the fibres we recorded were less than 250 micrometres in size, meaning they can be inhaled. This means we can be internally exposed to these microplastics and any contaminants attached to them.

Using human exposure models, we calculated that inhalation and ingestion rates were greatest in children under six years old. This is due to their lower relative body weight, smaller size, and higher breathing rate than adults. What’s more, young children typically have more contact with the floor, and tend to put their hands in their mouths more often than adults.

Microplastics are found not only in the sea, but in our food, beverages, and our homes.
Shutterstock

Children under six inhale around three times more microplastics than the average — 18,000 fibres, or 0.3 milligrams per kilogram of body weight per year. They would also ingest on average 6.1 milligrams of microplastics in dust per kg of body weight per year.

For a five-year-old, this would be equivalent to eating a garden pea’s worth of microplastics over the course of a year. But for many of these plastics there is no established safe level of exposure.

Our study indicated there are effective ways to minimise exposure.

First is the choice of flooring, with hard surfaces, including polished wood floors, likely to have fewer microplastics than carpeted floors.

Also, how often you clean makes a difference. Vacuuming floors at least weekly was associated with less microplastics in dust than those that were less frequently cleaned. So get cleaning!

Mark Patrick Taylor, Professor of Environmental Science and Human Health, Macquarie University; Neda Sharifi Soltani, Academic Casual, Macquarie University, and Scott P. Wilson, , Macquarie University

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

Istanbul Earthquake Risk & early Warning

Many New Zealand species are already at risk because of predators and habitat loss. Climate change makes things worse

Education Images/Universal Images Group via Getty Images

Cate Macinnis-Ng, University of Auckland and Angus Mcintosh, University of CanterburyIslands are biodiversity hotspots. They are home to 20% of the world’s plants and animals yet cover only 5% of the global landmass. But island ecosystems are highly vulnerable, threatened by habitat fragmentation and introduced invasive weeds and predators.

Climate change adds to all these stresses. In our recent paper, we use Aotearoa New Zealand as a case study to show how climate change accelerates biodiversity decline on islands by exacerbating existing conservation threats.

Many native birds are threatened by introduced predators such as rats, possums and cats.
Shutterstock/Imogen Warren

Aotearoa is one of the world’s biodiversity hotspots, with 80% of vascular plants, 81% of arthropods and 60% of land vertebrate animals found nowhere else.

Its evolutionary history is dominated by birds. Before the arrival of people, the only native land mammals were bats. But now, introduced predators threaten the survival of many species.

Complex interplay between many threats

Conservation efforts have rightly concentrated on the eradication of introduced predators, with world-leading success in the eradication of rats in particular.

Potential climate change impacts have been mostly ignored. Successive assessments by the Intergovernmental Panel on Climate Change (IPCC) highlight the lack of information for Aotearoa. This could be due to insufficient research, system complexity or a lack of impacts.

In the past, some researchers even dismissed climate change as an issue for biodiversity in Aotearoa. Our maritime climate is comparatively mild and already variable. As a result, organisms are expected to be well adapted to changing conditions.

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Despite its green image, NZ has world’s highest proportion of species at risk

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Palaeo-ecological records suggest few species extinctions despite abrupt environmental change during the Quaternary period (from 2.5 million years ago to present). But past climate change provides an incomplete picture of contemporary change because it did not include human-induced threats.

Habitat loss and fragmentation, land‐use change and complex interactions between native species and introduced predators or invasive weeds all contribute to these threats.

How climate change affects biodiversity

Species respond to climate change by evolving physiological adjustments, moving to new habitats or, in the worst cases, becoming extinct. These responses then change ecosystem processes, including species interactions and ecosystem functions (such as carbon uptake and storage).

Methods for identifying climate change impacts are either empirical and observational (field studies and manipulative experiments) or mechanistic (ecophysiological models). Mechanistic approaches allow predictions of impacts under future climate scenarios. But linking species and ecosystem change directly to climate can be challenging in a complex world where multiple stressors are at play.

Tuatara survive only on a few offshore islands and in sanctuaries.
Shutterstock/Ken Griffiths

There are several well-known examples of climate change impacts on species endemic to Aotearoa. First, warming of tuatara eggs changes the sex ratio of hatchlings. Hotter conditions produce more males, potentially threatening long-term survival of small, isolated populations.

Second, mast seeding (years of unusually high production of seed) is highly responsive to temperature and mast events are likely to increase under future climate change. During mast years, the seeds provide more food for invasive species like rats or mice, their populations explode in response to the abundant food and then, when the seed resource is used up, they turn to other food sources such as invertebrates and bird eggs. This has major impacts on native ecosystems.

How masting plants respond to climate change is complex and depends on the species. The full influence of climate is still emerging.

Every few years, beech trees produce significantly higher amounts of seed.
Shutterstock/sljones

Indirect effects of climate change

We identified a range of known and potential complex impacts of climate change in several ecosystems. The alpine zone is particularly vulnerable. Warming experiments showed rising temperatures extend the overlap between the flowering seasons of native alpine plants and invasive plants. This potentially increases competition for pollinators and could result in lower seed production.

Some large alpine birds, including the alpine parrot kea, will have fewer cool places to take refuge from invasive predators. This will cause
local extinctions in a process know as “thermal squeeze”.

Small alpine lakes, known as tarns, are not well understood but are also likely to suffer from thermal squeeze and increased drought periods. Warmer temperatures may also allow Australian brown tree frogs to invade further into these sensitive systems.

The alpine parrot kea lives in New Zealand’s mountain ranges.
Shutterstock/Peter Nordbaek Hansen

Climate change disproportionately affects Indigenous people worldwide. In Aotearoa, culturally significant species such as tītī (sooty shearwater) and harakeke (flax) will be influenced by climate change.

The breeding success of tītī, which are harvested traditionally, is strongly influenced by the El Niño Southern Oscillation (ENSO) cycle. As ENSO intensifies under climate change, numbers of young surviving are decreasing. For harakeke, future climate projections predict changes in plant distribution, potentially making weaving materials unavailable to some hapū (subtribes).

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Traditional knowledge helps Indigenous people adapt to climate crisis, research shows

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Mātauranga, the Indigenous knowledge of Māori, provides insights on climate change that haven’t been captured in western science. For instance, the Māori calendar, maramataka, has been developed over centuries of observations.

Maramataka for each hāpu (subtribe) provide guidance for the timing of gathering mahinga kai (traditional food sources). This includes the gathering of fish and other seafood, planting of crops and harvesting food. Because this calendar is based on knowledge that has accrued over generations, some changes in timing and distributions due to environmental or climate change may be captured in these oral histories.

Climate change is here now

Future projections of climate change are complicated in Aotearoa — but it is clear the climate is already changing.

Last year was the seventh hottest on record for Aotearoa. Many parts of the country suffered severe summer drought. NASA captured images of browned landscapes across the country.

These images show how the Hawke’s Bay dried out between the summer (December to February) periods of 2019 (left) and 2020 (right).
NASA, CC BY-SA

Much of the focus of climate change research has been in agricultural and other human landscapes but we need more effort to quantify the threat for our endemic systems.

On islands across the world, rising sea levels and more severe extreme weather events are threatening the survival of endemic species and ecosystems. We need to understand the complicated processes through which climate change interacts with other threats to ensure the success of conservation projects.

While we focused on terrestrial and freshwater systems, marine and near-shore ecosystems are also suffering because of ocean acidification, rising sea levels and marine heatwaves. These processes threaten marine productivity, fisheries and mahinga kai resources.

And for long-term conservation success, we need to consider both direct and indirect impacts of climate change on our unique species and ecosystems.

Cate Macinnis-Ng, Associate Professor, University of Auckland and Angus Mcintosh, Professor of Freshwater Ecology, University of Canterbury

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

Australia’s smallest fish among 22 at risk of extinction within two decades

Red-finned blue-eye
Bush Heritage Australia / Adam Kerezsy

Mark Lintermans, University of Canberra; Hayley Geyle, Charles Darwin University; Jaana Dielenberg, The University of Queensland; John Woinarski, Charles Darwin University; Stephen Beatty, Murdoch University, and Stephen Garnett, Charles Darwin University

The tragic fish kills in the lower Darling River drew attention to the plight of Australia’s freshwater fish, but they’ve been in trouble for a long time.

Many species have declined sharply in recent decades, and as many as 90 of Australia’s 315 freshwater fish species may now meet international criteria as threatened.

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No Australian fish species is yet listed officially as extinct, but some have almost certainly been lost before scientists even knew they existed. With so many species at risk, understanding which are in greatest peril is a vital first step in preventing extinctions.

This is what our new research has done. We’ve identified 20 freshwater fish species with a 50% or greater probability of extinction within the next two decades, and a further two with a 40-50% chance – unless there’s new targeted conservation action.

The Australian freshwater fishes at greatest risk of extinction.

Slipping through the conservation cracks

Many small-bodied species, including Australia’s smallest fish the red-finned blue-eye, look likely to be lost within a single human generation. These fish have evolved over millions of years.

Twelve of the species identified have only been formally described in the past decade, and seven are still awaiting description.

This highlights the urgent need to act before species are listed under the national legislation that gives fishes their conservation status, and even before they’re formally described.

These processes can take many years, at which point it may be too late for some species.

More than half the species on our list are galaxiids – small, scaleless fish, that live in cooler, upland streams and lakes. Trout, an introduced, predatory species, also favour these habitats, and the trout have taken a heavy toll on galaxiids and many other small species in southern Australia.

Victoria’s Shaw galaxias – one of 14 galaxias species identified at high risk of extinction.
Tarmo Raadik

For example, the Victorian Shaw galaxias has been eaten out of much of its former range. Now just 80 individuals survive, protected by a waterfall from the trout below. We estimate the Shaw galaxias has an 80% chance or more of extinction within the next 20 years.

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Double trouble: this plucky little fish survived Black Summer, but there’s worse to come

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Many galaxiids do not thrive or readily breed in captivity, so suitable trout-free streams are essential for their survival.

Improving trout management requires an urgent, sustained conservation effort, including collaborations with recreational fishers, increased awareness and changing values among government and key sectors of society.

Without this, trout will almost certainly cause many native galaxiids to go extinct.

This waterfall in NSW is all that protects the last population of stocky galaxias from the predatory trout below.
Mark Lintermans

Native fish out of their natural place can also be a problem. For example, sooty and khaki grunters – native fishing species people in northern Australia have widely moved – threatening the ancient Bloomfield River cod.

One disaster can lead to extinction

All of the most imperilled species are now highly localised, which means they’re restricted to very small areas. Their distributions range from only four to 44 square kilometres.

A single catastrophic event could completely wipe out these species, such as a large bushfire that fills their streams with ash and robs them of oxygen.

The SW Victoria River blackfish persists as three very small, isolated populations. The main threat to this species is recreational angling.
Tarmo Raadik

For example, until 2019 the Yalmy galaxias had survived in the cool creeks of the Snowy River National Park. But after the devastating Black Summer fires, just two individuals survived, one male and one female, in separate areas.

Millions of years of evolution could be lost if a planned reunion is too late.

One of the key steps to reduce this risk is moving fish to new safe locations so there are more populations. Researchers choose these new locations carefully to make sure they’re suitable for different species.

Climate change is another threat to all identified species, as it’s likely to reduce flows and water quality, or increase fires, storms and flooding. Many species have been forced to the edge of their range and a prolonged drought could dry their remaining habitat.

The short-tail galaxias existed in two small separated populations in creeks of the upper Tuross River Catchment, in the south coast of NSW. One stream dried in the recent drought, and the other was burnt in the subsequent fires.

Luckily the species is still hanging on in the burnt catchment, but only a single individual has been found in the drought-affected creek.

The main threat to the Daintree rainbowfish is loss of stream flow due to drought, climate change and water extraction.
Michael Hammer / Museum and Art Gallery of the Northern Territory, Author provided

Unlisted, unprotected

Our study is part of a larger project to identify plants and animals at high risk of extinction.

We found the extinction risks of the 22 freshwater fish species are much higher than those of the top 20 birds or mammals, yet receive far less conservation effort.

Only three of the highly imperilled fish species are currently listed as threatened under national environmental legislation: the red-finned blue-eye, Swan galaxias and little pygmy perch.

Listing species is vital to provide protection to survivors and can prompt recovery action. Given our research, 19 fish species should urgently be added to the national threatened species list, but conservation action should start now.

The little pygmy perch in the far south-west corner of WA is one of only three of the 22 imperilled species identified that’s formally protected under Australian laws.
Stephen Beatty/Harry Butler Institute, Murdoch University

Small native freshwater fishes are worth saving. They play a vital role in our aquatic ecosystems, such as predating on pest insect larvae, and are part of our natural heritage.

By identifying and drawing attention to their plight, we are aiming to change their fates. We cannot continue with business as usual if we want to prevent their extinctions.

Mark Lintermans, Associate professor, University of Canberra; Hayley Geyle, Research Assistant, Charles Darwin University; Jaana Dielenberg, Science Communication Manager, The University of Queensland; John Woinarski, Professor (conservation biology), Charles Darwin University; Stephen Beatty, Research Leader (Catchments to Coast), Centre for Sustainable Aquatic Ecosystems, Harry Butler Institute, Murdoch University, and Stephen Garnett, Professor of Conservation and Sustainable Livelihoods, Charles Darwin University

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

12 simple ways you can reduce bushfire risk to older homes

There are no guarantees in bushfires, but you can improve the odds your house survives a blaze.
Photo by Edward Doody, courtesy of Arkin Tilt Architects, Author provided

Douglas Brown, Western Sydney University

Seventy-five years of Australian research into how houses respond to bushfire has identified 21 main weak points in houses and the area immediately surrounding them.

In recent decades this knowledge has been used to inform new building construction. But older houses are generally not built to the same standard, unless they have been significantly renovated.

Older homes make up the majority of buildings in bushfire prone-areas. There are some simple things that can improve the performance of an older house in a bushfire. Here are 12 suggestions: six simple projects that could be done over a weekend or two, and six low-cost things you could do in a single afternoon.

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Six weekend projects:

1. Remove some garden beds next to the house

This is particularly true for garden beds near timber-framed windows and doors. For timber and fibro homes, garden beds adjacent to the house should be avoided entirely. At the very least prune dense bushes close to timber-framed windows back hard.

2. Sand and repaint weathered timber door and window frames

Over time, paint peels and cracks appear in the exposed and weathered timber. During a bushfire, embers can lodge in these cracks and ignite.

3. Enclose the subfloor with a metal mesh

Flammable items are often stored underneath the house. If this area is not enclosed these items will catch, often due to ember attack, and pose a threat to every room in the house. The exposed underside of timber floors can be protected with a lightweight, non-combustible layer.

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4. Repair or replace weathered timber decking

Just as embers can land in cracks in door and window frames, the same can also happen to weathered timber decking. Most decks are right next to the house and if they go up fire easily spreads to the home.

5. Have a 1-2 metre non-flammable area immediately around your house

Think of it as an additional protective defence area. You could use gravel, paving tiles, bricks, concrete, or ground rock such as scoria.

6. Get a professional roof inspection

Roofs gradually weaken and require maintenance. A professional roof repairer can check that tiles are in place, repair damaged ridge tiles, and ensure that skylights, air vents, evaporative coolers, and solar panels are in good order and are free from gaps where embers could enter.

The product specifications for timber door and window frames, metal mesh, and decking materials can be found in the relevant Australian Standard and steel construction standard. Actual requirements for houses vary according to the bushfire attack level associated with a specific block of land.

Open sub floor spaces are vulnerable, especially if used to store flammable material.
Douglas Brown, Author provided

Six easy afternoon projects

1. Replace natural coil doormats with synthetic

While they appear harmless, natural organic doormats can cause a fire to grow if they ignite. Due to their density they burn for a long time, and can spread flames to timber door frames. A synthetic mat will only flare up for a short time.

2. Remove organic mulch from garden beds next to the house

Burning embers can easily ignite dried-out organic mulch, setting fire to surrounding plants. If garden beds are near the house, particularly timber door and window frames, the danger is increased. Either remove mulch in garden beds next to the house or – if the mulch is suitable – dig it in deeply.

3. Store firewood in an enclosed metal container

It is best to store wood well away from the house, but no one wants to walk metres in cold winters to get that wood. So some firewood is often stored close to the house on a burnable deck, and often it’s left there over summer. Putting it into a large metal container can remove that fire risk.

4. Remove flammable material from the front porch, roof cavity, decking and underfloor area

When embers enter the roof cavity and underneath the house, flames can rapidly spread to every room. It is vital to keep these areas clear of flammable materials.

5. Replace timber benches on timber decks with synthetic ones

A timber bench on a timber deck next to a timber house is an unnecessary risk, similar to having a wood pile on a timber deck.

6. Turn pressure relief valves on outside gas bottles away from the house

Both the 2003 Canberra and the 2016 Wye River bushfires showed the danger of having gas bottle valves facing the house. In both fires, houses were destroyed when either the gas plume flamed or gas bottles exploded.

While these projects will improve the bushfire protection of your home, they can’t guarantee your home will survive a bushfire, especially during catastrophic bushfire conditions. It is also crucial to upgrade your home insurance so you can meet the higher costs of new building standards, in the event you have to rebuild. And in all cases, act on warnings given by your state or territory fire authority.

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The advice given in this article is general and may not suit every circumstance.

Douglas Brown, Casual Academic, Western Sydney University

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

Despite its green image, NZ has world’s highest proportion of species at risk

About 74% of New Zealand’s land birds, including the endemic takahe, are either threatened or at risk of extinction.
AAP/Brendon Doran, CC BY-ND

Michael (Mike) Joy, Victoria University of Wellington and Sylvie McLean, Victoria University of Wellington

A recent update on the state of New Zealand’s environment paints a particularly bleak picture about the loss of native ecosystems and the plants and animals within them.

Almost two-thirds of rare ecosystems are threatened by collapse, according to Environment Aotearoa 2019, and thousands of species are either threatened or at risk of extinction. Nowhere is the loss of biodiversity more pronounced than in Aotearoa New Zealand: we have the highest proportion of threatened indigenous species in the world.

This includes 90% of all seabirds, 84% of reptiles, 76% of freshwater fish and 74% of terrestrial birds. And this may well be an underestimate. An additional one-third of named species are listed as “data deficient”. It is likely many more would be on the threatened list had they been assessed. Then there are the species that have not been named and we have no idea about.

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Why biological diversity matters

Biodiversity is a word that means different things to different people. Its use has exploded recently as more people appreciate the magnitude of its decline and its importance to people’s future.

Popularly biodiversity is understood as the number of species in a given country or ecosystem. For scientists, the concept is deeper. It includes genetic and ecosystem diversity and has crucial components such as endemicity (species found nowhere else), native diversity (the proportion of native species) and keystone species (species that are crucial to ecosystem function).

Globally, biodiversity in all its guises is undergoing an unprecedented decline. Estimates are that we are now losing species at more than 1,000 times the background or natural rate. People are also moving species outside their native ranges, and this results in a global biological homogenisation and has helped a small number of species to thrive in human-dominated habitats across the world.

The classification of threat status, globally and in New Zealand, is complex. There are multiple levels, ranging from “nationally critical” to “at risk”. When describing levels of biodiversity decline, it is simpler to look at the proportion of species listed as “not threatened”.

In New Zealand, only around 18% of beetles, 26% of freshwater fish, 38% of marine mammals, 12% lizards, 5% of snails and 50% of plants are listed as not threatened or not at risk. This is a rather dire situation, especially given the 100%-pure slogan used to market Aotearoa New Zealand overseas.

Ineffective legal protection

Another important facet of biodiversity decline is that New Zealand has many endemic species, with around 40% of plants, 90% of fungi, 70% of animals and 80% of freshwater fish found nowhere else. If they are lost here they are lost entirely.

In a recent report to the UN Convention on Biological Diversity, the Department of Conservation could not say whether New Zealand’s biodiversity is declining or not. One quarter of the nearly 4,000 species currently classified as threatened or at risk have only been assessed once and there is no way to know whether their conservation status has changed. Of the remaining roughly 3,000 threatened or at risk species, 10% had worsened to a more threatened ranking. Only 3% had improved.

The numbers above show the failure of legislation intended to protect biodiversity in Aotearoa New Zealand. The Wildlife Act (1953) purportedly gives absolute protection to all wildlife. But it is not enforced in any meaningful way, and therefore has had no impact on biodiversity conservation.

The Native Plants Protection Act (1934) stipulates that native plants have protection on conservation land but makes no mention of protection outside that and, in any case, is not enforced. Native fish are not covered by the Wildlife Act and the Freshwater Fisheries Act affords them no protection either.

Human impact on land

Apart from ineffective species protection, another factor is the loss of habitat and ecosystems through land-use change for agricultural and urban intensification. The first changes happened with Polynesian arrival, and then again after European colonisation, including massive forest clearance and wetland drainage. More recently, the expansion of dairy farms has contributed to significant biodiversity losses.

Freshwater fish are a good example. The increase in the proportion of threatened species has gone from around one-quarter in the early 1990s to three-quarters now. This recent loss reveals the failure of successive governments to protect biota, their habitats and ecosystems. Lowland coastal forests and wetlands in particular continue to be degraded by human activity.

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Indigenous terrestrial vegetation cover is now less than 30%, down from approximately 90% in pre-human times. One-third of the country is covered in exotic grasslands.

About one-third of the country is putatively protected by being within the conservation estate. This sounds impressive, but it obscures the true state of protected areas. The ecosystem types in the estate are far from a representative selection. It mostly contains areas that are too steep to farm and too inhospitable to live in.

The failure to protect habitats is reflected in the reduction in ecosystem diversity: 62% of the ecosystems classified as rare are now listed as threatened, and more than 90% of wetlands have been destroyed. This loss is not confined to the past. Estimates are that 214 wetlands (1,250 ha) were lost between 2001 and 2016, and a further 746 wetlands declined in size.

Marine conservation

Protection levels of marine habitats are even worse. New Zealand’s marine area is 15 times larger than its land area, but marine biodiversity is poorly regulated. Only 0.4% is covered by “no-take” marine reserves.

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As a signatory to the UN Sustainable Development Goals (SDGs), New Zealand is obligated to reduce biodiversity loss. We have committed to achieving SDG 14 (life under water) and SDG 15 (life on land). The former stipulates that we “conserve and sustainably use the oceans, seas and marine resources for sustainable development”. The latter that we “protect, restore and promote sustainable use of terrestrial ecosystems, sustainably manage forests, combat desertification, and halt and reverse land degradation and halt biodiversity loss”.

There is no sign of any real achievement in reducing biodiversity loss. While New Zealand produced a national biodiversity strategy in 2000, it has been largely ineffective at improving the state of biodiversity. As the OECD noted, the strategy and plan lack clarity and clear implementation pathways.

We have tried writing plans with no teeth. Now it is time for action from all levels of society. Cities and regions need to ensure parks and protected areas are adequately managed. Government must work to update ineffective legislation and commit to enforcing the law.

Michael (Mike) Joy, Senior Researcher; Institute for Governance and Policy Studies, Victoria University of Wellington and Sylvie McLean, Masters Student in Environmental Studies, Victoria University of Wellington

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

Trapdoor spider species that stay local put themselves at risk

A palisade trapdoor spider of the new species E. turrificus walks across the rainforest floor near Maleny, Queensland.
Jeremy Wilson, Author provided

Jeremy Dean Wilson, Griffith University

Several new species of trapdoor spiders found in Queensland are finally described in an article published this month in Invertebrate Systematics.

But each of the new species occurs in only its own single, isolated patch of rainforest in southeastern Queensland, and nowhere else.

Because these species have such tiny natural distributions, they are especially vulnerable to extinction.

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Unique spider burrows

These newly described spiders have been given the common name palisade trapdoor spiders because of the strange and unique burrows they construct. The entrance to the burrow projects out from the surrounding soil like a miniature turret.

The remarkable palisade burrows constructed by two different species of palisade trapdoor spider. The burrow entrances project from the surrounding soil.
Jeremy Wilson (left), Michael Rix (right)

Not only that, but each of the four new palisade trapdoor spider species constructs its own unique type of burrow.

One species, found in national parkland near Gympie and known scientifically as Euoplos crenatus, constructs a particularly elaborate burrow. The hinged door that covers the burrow entrance is adorned with several rounded lobes which project from the door’s circumference.

This marvel of natural architecture is constructed by the spider using silk and soil. No other spider species in the world constructs something similar.

This species was originally discovered by local naturalists Kelvin and Amelia Nielsen in 1999, who then guided researchers back to the discovery location in 2016 to collect specimens so the species could be formally named.

The burrow entrance of Euoplos crenatus, with its peculiar ‘crenate’ burrow door.
Michael Rix

Another species, Euoplos thynnearum, constructs a burrow entrance with a thick lip within which the burrow door sits. It’s found in the Mary Cairncross Scenic Reserve, a 55-hectare patch of subtropical rainforest popular with visitors to the Sunshine Coast hinterland.

This species is named after Elizabeth, Mabel and Mary Thynne, who originally donated the reserve land to the local council in 1941 to honour their mother Mary Thynne (née Cairncross). Currently, this species is known to occur only within the reserve and in other rainforest patches in the immediate vicinity.

Burrow entrances of the new palisade trapdoor spider species Euoplos thynnearum. This species is largely restricted to a single rainforest patch, occurring within Mary Cairncross Scenic Reserve near Maleny.
Michael Rix

Short-range species at risk

Species that only only occur in a very small area, like these new palisade trapdoor spider species, are known as short-range endemic species.

Although scientists are naming new species at a faster rate than ever before, estimates of the total number of species on Earth still suggest that most animal species have not been formally named. With so much work still to do, some scientists have chosen to prioritise work on particular types of animals that are especially vulnerable to extinction.

In 2002, Mark Harvey, an arachnologist from the Western Australian Museum, proposed that scientists should prioritise the discovery and description of short-range endemic species.

He reasoned that the small ranges of these species make them inherently vulnerable to extinction, and that identifying, naming and studying them is the first step to protecting them.

The strange burrows of the trapdoor spider species Euoplos crenatus project out from between the roots and leaf-litter on the bank of a creek in a rainforest patch near Gympie, Queensland.
Jeremy Wilson

Staying local

For trapdoor spiders, short-range endemism is the rule, not the exception. These spiders live their entire lives in a burrow. Juvenile spiders walk only short distances from their mother’s burrow, before constructing a burrow of their own.

Usually, these spiders will then remain in the same burrow for the remainder of their lives, enlarging it as they grow.

Examples of different trapdoor spider species from eastern Australia. Top left, Arbanitis longipes; top right, Heteromigas sp.; bottom left, Cataxia sp.; bottom right, Namea sp.
Jeremy Wilson

Adult male trapdoor spiders will also leave their burrow to breed, but will only travel relatively short distances. Over time, this extremely limited dispersal ability has led to the evolution of many different trapdoor spider species, each of which occurs in only a very small area.

Since 2012, a research team, led by Queensland Museum researcher Michael Rix, has been trying to discover and name all species of spiny trapdoor spider – this group includes the palisade trapdoor spiders, as well as other strange trapdoor spider species such as the shield-backed trapdoor spiders of Western Australia.

A shield-backed trapdoor spider from Western Australia, showing the distinctive hardened disk on its abdomen which the spider uses to ‘plug’ its burrow as a protection from predators.
Mark Harvey

So far, this project has led to the description of more than 100 new species from throughout Australia, some of which are already classified as threatened by federal and state governments.

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The most iconic of these is Idiosoma nigrum (also a shield-backed trapdoor spider), which is a listed threatened species.

The discovery of all these weird and wonderful spider species should remind us that Australia has some of the most remarkable invertebrate species in the world, and new species are waiting to be discovered in the national parks and reserves which occur around, and even within, our towns and cities – under our noses.

Next time you visit a national park, or drive past a patch of forest while commuting along Australia’s east coast, think to yourself, what might be living in there? Do those species occur anywhere else? And above all, if we lose that forest remnant, what unique species might disappear along with it?

Jeremy Dean Wilson, Ph.D candidate, Department of Environment & Science, Griffith University, Griffith University

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