Pacific Island bats are utterly fascinating, yet under threat and overlooked. Meet 4 species

Artwork by Arison Kul from Lae Papua New Guinea.

John Martin, University of Sydney; David L. Waldien, Christopher Newport University; Junior Novera, The University of Queensland; Justin A. Welbergen, Western Sydney University; Malik OEDIN, Université de Nouvelle Calédonie; Nicola Hanrahan, Charles Darwin University; Tigga Kingston, Texas Tech University, and Tyrone Lavery, Australian National UniversityAm I not pretty enough? This article is part of The Conversation’s new series introducing you to unloved animals that need our help.

A whopping 191 different bat species live in the Pacific Islands across Micronesia, Melanesia, and Polynesia — but these are, collectively, the most imperilled in the world. In fact, five of the nine bat species that have gone extinct in the last 160 years have come from this region.

For too long, the conservation of Pacific Island bats has been largely overlooked in science. Of the 191 existing species, 25% are threatened with extinction, and we lack information to assess the status of a further 15%.

Just as these bats are rare and far-flung across the Pacific islands, so is the expertise and research needed to conserve them along with the vital ecosystem services they provide, such as pollination, seed dispersal, and insect control.

The first-ever Pacific Islands Bat Forum, held earlier this month, sought to change this, bringing together a new network of researchers, conservationists, and community members — 380 people from 40 countries and territories — dedicated to their survival.

So, why should we care about these bats anyway?

Conserving Pacific Island bats is paramount for preserving the region’s diverse human cultures and for safeguarding the healthy functioning of island ecosystems.

In many Pacific Island nations, bats have great cultural significance as totems, food, and traditional currency.

Bats are the largest land animals on many of the Pacific islands, and are vital “keystone species”, maintaining the structure of ecological communities.

Yet, Pacific Island bats are increasingly under threat, including from intensifying land use (farming, housing, roads) invasive species (rats, cats, snakes, ants), and human harvesting. They’re also vulnerable to climate change, which heightens sea levels and increases the intensity of cyclones and heatwaves.

So let’s meet four fascinating — but threatened — Pacific Island bats that deserve more attention.

1. Pacific sheath-tailed bat

Conservation status: endangered

Distribution: American Samoa, Federated States of Micronesia, Fiji, Guam, Northern Mariana Islands, Palau, Samoa, Tonga

Pacific Sheath tailed Bat (*Emballonura semicaudata*)
Ron Leidich

The Pacific sheath-tailed bat (Emballonura semicaudata) weighs just five-grams and has a weak, fluttering flight. Yet somehow, it has colonised some of the smaller and more isolated islands across the Pacific, from Samoa to Palau. That’s across 6,000 kilometres of ocean!

Over the past decade, this insect-eating, cave-roosting bat has disappeared from around 50% of islands where it has been recorded. The reasons for this are unclear. Disturbance of cave roosts, introduced species such as lantana and goats, and increasing use of pesticides, may all have played a part.

Unfortunately, the Pacific sheath-tailed bat is now presumed extinct in many former parts of its range, including American Samoa, Tonga, and several islands of the Northern Mariana Islands. This leaves Palau, the Federated States of Micronesia, and Fiji as remaining strongholds for the species, though data is limited.

2. Montane monkey-faced bat

Conservation status: critically endangered

Distribution: Solomon Islands

New Georgian monkey-faced bat *Pteralopex taki* — no picture exists of the Montane monkey-faced bat.
Tyrone Lavery

There are six species of monkey-faced bat — all are threatened, and all are limited to islands across the Solomon Islands, Bougainville, and Fiji.

The montane monkey-faced bat (Pteralopex pulchra) is one species, and weighs around 280 grams, eats fruit and nectar, and has incredibly robust teeth. But perhaps most startling is its ruby-red eyes and wing membranes that are marbled with white and black.

The montane monkey-faced bat has been recorded only once by scientists on a single mountain (Mt Makarakomburu) above the altitude of 1,250 metres, on Guadalcanal Island. This tiny range makes it vulnerable to rare, extreme events such as cyclones, which could wipe out a whole population in one swoop. And being limited to mountain-top cloud forests could place it at greater risk from climate change.

It’s an extreme example of both the endemism (species living in a small, defined area) and inadequacies of scientific knowledge that challenge Pacific island bat conservation.

3. Ornate flying-fox

Conservation status: vulnerable

Distribution: New Caledonia

Ornate flying-fox (*Pteropus ornatus*)‘
Malik Oedin, IAC

Like many fruit bats across the Pacific, New Caledonia’s endemic ornate flying-fox (Pteropus ornatus) is an emblematic species. Flying-foxes are hunted for bush meat, used as part of cultural practices by the Kanaks (Melanesian first settlers), are totems for some clans, and feature as a side dish during the “New Yam celebration” each year. Their bones and hair are also used to make traditional money.

Because they’re so highly prized, flying-foxes can be subject to illegal trafficking. Despite the Northern and Southern Provinces of New Caledonia having regulated hunting, flying-fox populations continue to decline. Recent studies predict 80% of the population will be gone in the next 30 years if hunting continues at current levels.

On a positive note, earlier this year the Northern Province launched a conservation management program to protect flying-fox populations while incorporating cultural values and practices.

4. Fijian free-tailed bat

Conservation status: endangered

Distribution: Fiji, Vanuatu

Fijian free tailed bat (*Chaerophon bregullae*)
Dave Waldien

In many ways, the Fijian free-tailed bat (Chaerephon bregullae) has become the face of proactive bat conservation in the Pacific Islands. This insect-eating bat requires caves to roost during the day and is threatened when these caves are disturbed by humans as it interrupts their daytime roosting. The loss of foraging habitat is another major threat.

The only known colony of reproducing females lives in Nakanacagi Cave in Fiji, with around 7,000 bats. In 2014, an international consortium with Fijian conservationists and community members came together to protect Nakanacagi Cave. As a result, it became recognised as a protected area in 2018.

But this species shares many characteristics with three of the nine bat species that have gone extinct globally. This includes being a habitat specialist, its unknown cause of decline, and its potential exposure to chemicals through insect foraging. It’s important we continue to pay close attention to its well-being.

Where do we go from here?

The perspectives of local knowledge from individual islands aren’t always captured in global scientific assessments of wildlife.

In many Pacific Islands, bats aren’t protected by national laws. Instead, in many countries, most land is under customary ownership, which means it’s owned by Indigenous peoples. This includes land in Papua New Guinea, Solomon Islands, and Vanuatu. Consequently, community landowners have the power to enact their own conservation actions.

The emerging Pacific Bat Network, inspired by the recent forum, aims to foster collaborative relationships between scientific conservationists and local leaders for species protection, while respecting cultural practices.

As the Baru Conservation Alliance — a locally-led, not-for-profit group from Malaita, Solomon Islands — put it in their talk at the forum:

conservation is not a new thing for Kwaio.

Now the forum has ended, the diverse network of people passionate about bat conservation is primed to work together to strengthen the conservation of these unique and treasured bats of the Pacific.

John Martin, Research Scientist, Taronga Conservation Society Australia & Adjunct lecturer, University of Sydney; David L. Waldien, Adjunct assistant professor, Christopher Newport University; Junior Novera, PhD Candidate, School of Biological Sciences, The University of Queensland; Justin A. Welbergen, President of the Australasian Bat Society | Associate Professor of Animal Ecology, Western Sydney University; Malik OEDIN, PhD Population Biology and Ecology, Université de Nouvelle Calédonie; Nicola Hanrahan, Terrestrial Ecologist, Department of Environment, Parks and Water Security, Northern Territory Government & Visiting Fellow, Charles Darwin University; Tigga Kingston, Professor, Department of Biological Sciences, Texas Tech University, and Tyrone Lavery, Postdoctoral Research Fellow, Australian National University

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

Australia’s threatened species plan has failed on several counts. Without change, more extinctions are assured

Euan Ritchie, Deakin University and Ayesha Tulloch, University of SydneyAustralia is globally renowned for its abysmal conservation record – in roughly 230 years we’ve overseen the extinction of more mammal species than any other nation. The federal government’s Threatened Species Strategy was meant to address this confronting situation.

The final report on the five-year strategy has just been published. In it, Threatened Species Commissioner Dr Sally Box acknowledges while the plan had some important wins, it fell short in several areas, writing:

…there is much more work to do to ensure our native plants and animals thrive into the future, and this will require an ongoing collective effort.

Clearly, Australia must urgently chart a course towards better environmental and biodiversity outcomes. That means reflecting honestly on our successes and failures so far.

How did the strategy perform?

The strategy, announced in 2015, set 13 targets linked to three focus areas:

feral cat management
improving the population trajectories of 20 mammal, 21 bird and 30 plant species
improving practices to recover threatened species populations.

Given the scale of the problem, five years was never enough time to turn things around. Indeed, as the chart below shows, the report card indicates five “red lights” (targets not met) and three “orange lights” (targets only partially met). It gave just five “green lights” for targets met.

Year Five - Final Report — Summary of the Threatened Species Strategy’s targets and outcomes.
Department of Agriculture, Water and the Environment

Falling short on feral cats

Feral cats were arguably the most prominent focus of the strategy, despite other threats requiring as much or more attention, such as habitat destruction via land clearing.

However, the strategy did help start a national conversation about the damage cats wreak on wildlife and ecosystems, and how this can be better managed.

In the five years to the end of 2020, an estimated 1.5 million feral cats were killed under the strategy – 500,000 short of the 2 million goal. But this estimate is uncertain due to a lack of systematic data collection. In particular, the number of cats culled by farmers, amateur hunters and shooters is under-reported. And more broadly, information is scattered across local councils, non-government conservation agencies and other sources.

Australia’s feral cat population fluctuates according to rainfall, which determines the availability of prey – numbering between 2.1 million and 6.3 million. Limited investment in monitoring makes it impossible to know whether the average of 300,000 cats killed each year over the past five years will be enough for native wildlife to recover.

The government also failed in its goal to eradicate cats from five islands, only achieving this on Dirk Hartog Island off Western Australia. Importantly, that effort began in 2014, before the strategy was launched. And it was primarily funded by the WA government and an industry offset scheme, so the federal government can’t really claim this success.

On a positive note, ten mainland areas excluding feral cats have been established or are nearly complete. Such areas are a vital lifeline for some wildlife species and can enable native species reintroductions in the future.

feral cat holds dead bird — Feral cats were eradicated from just one island under the strategy.
Mark Marathon/Threatened Species Recovery Hub

Priority species: how did we do?

The strategy met its target of ensuring recovery actions were underway for at least 50 threatened plant species and 60 ecological communities. It also made good headway into storing all Australia’s 1,400 threatened plant species in seed banks. This is good news.

The bad news is that, even with recovery actions, the population trajectories of most priority species failed to improve. For the 24 out of about 70 priority species where population numbers were deemed to have “improved” over five years, about 30% simply got worse at a slower rate than in the decade prior. This can hardly be deemed a success.

Mala with baby in pouch — Populations of the mala, or Rufous Hare-wallaby, were improving before the strategy.
Wayne Lawler/Australian Wildlife Conservancy

What’s more, the populations of at least eight priority species, including the eastern barred bandicoot, eastern bettong, Gilbert’s potoroo, mala, woylie, numbat and helmeted honeyeater, were increasing before the strategy began – and five of these deteriorated under the strategy.

The finding that more priority species recovery efforts failed than succeeded means either:

the wrong actions were implemented
the right actions were implemented but insufficient effort and funding were dedicated to recovery
the trajectories of the species selected for action simply couldn’t be improved in a 5-year window.

All these problems are alarming but can be rectified. For example, the government’s new Threatened Species Strategy, released in May, contains a more evidence-based process for determining priority species.

For some species, it’s unclear whether success can be attributed to the strategy. Some species with improved trajectories, such as the helmeted honeyeater, would likely have improved regardless, thanks to many years of community and other organisation’s conservation efforts before the strategy began.

Conservation worker releases woylie — The improved outlook for some species is due to conservation efforts before the federal strategy.
WA Department of Environment and Conservation

What must change

According to the report, habitat loss is a key threat to more than half the 71 priority species in the strategy. But the strategy does not directly address habitat loss or climate change, saying other government policies are addressing those threats.

We believe habitat loss and climate change must be addressed immediately.

Of the priority bird species threatened by land clearing and fragmentation, the trajectory of most – including the swift parrot and malleefowl – did not improve under the five years of the strategy. For several, such as the Australasian bittern and regent honeyeater, the trajectory worsened.

Preventing and reversing habitat loss will take years of dedicated restoration, stronger legislation and enforcement. It also requires community engagement, because much threatened species habitat is on private properties.

Effective conservation also requires raising public awareness of the dire predicament of Australia’s 1,900-plus threatened species and ecological communities. But successive governments have sought to sugarcoat our failings over many decades.

Bushfires and other extreme events hampered the strategy’s recovery efforts. But climate change means such events are likely to worsen. The risks of failure should form part of conservation planning – and of course, Australia requires an effective plan for emissions reduction.

The strategy helped increase awareness of the plight our unique species face. Dedicated community groups had already spent years volunteering to monitor and recover populations, and the strategy helped fund some of these actions.

However, proper investment in conservation – such as actions to reduce threats, and establish and maintain protected areas – is urgently needed. The strategy is merely one step on the long and challenging road to conserving Australia’s precious species and ecosystems.

Euan Ritchie, Professor in Wildlife Ecology and Conservation, Centre for Integrative Ecology, School of Life & Environmental Sciences, Deakin University and Ayesha Tulloch, DECRA Research Fellow, University of Sydney

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

Australia’s threatened species plan sends in the ambulances but ignores glaring dangers

Euan Ritchie, Deakin University; Ayesha Tulloch, University of Sydney, and Don Driscoll, Deakin UniversityAustralia is unquestionably in the midst of an extinction crisis. Some 34 native mammal species have been driven to extinction since European invasion, and threatened species and ecological communities now number more than 1,900.

On Friday, federal environment minister Sussan Ley released Australia’s second Threatened Species Strategy – a roadmap for combating threats to native plants, animals and ecological communities.

The ten-year plan builds on the first strategy launched in 2015, and contains welcome changes. But there remain serious questions about how the plan will be funded and implemented – and quite possibly undermined by other federal government policies.

In essence, the strategy sends a few extra ambulances to the bottom of the cliff, rather than installing a fence at the top to stop species tumbling over.

orange bellied parrot — The plan to save threatened species, such as the orange-bellied parrot, contains both improvements and concerns.
Shutterstock

First, the good news

It would be useful when assessing the new strategy to know how the previous one measured up. Unfortunately, federal environment officials have not yet released the last report card for that strategy, which makes it hard to identify what worked and what didn’t.

Nonetheless, the second strategy differs from the first in important ways.

The first strategy was criticised for its heavy focus on feral cats. Other problems which are just as (and often more) threatening to vulnerable species were not given the same attention. These include altered fire regimes, land clearing and other invasive species such as weeds and rabbits. Importantly, the new strategy recognises a greater number of key threats to wildlife and their habitats.

It also expands the number of actions for threatened species recovery from four to eight. Such actions may include tackling weeds and diseases, relocating species and identifying climate refuges.

The first strategy was rightly questioned for a somewhat myopic focus on 20 mammal, 20 bird and 30 plant species. It also lacked a transparent and evidence-based process for determining how a species was selected as a priority.

The new strategy could expand the types of species targeted for conservation to include fish, amphibian, reptile and invertebrate species. Also, the process for prioritising species for action promises to be more rigorous – assessed against six principles supported by science and existing conservation frameworks.

Significantly, priority places in need of conservation will likewise be assessed through a formal process. This is welcome if it ultimately protects habitats and broader ecosystems, an essential element of avoiding species extinctions.

Tropical savanna in good condition.
Suzanne Prober

But challenges remain

The strategy talks of improving species trajectories, but it’s unclear what would constitute success in this regard.

If a threatened species’ population numbers were declining at a slower rate due to an intervention, would that intervention be deemed a success? Will successful actions be attributed to the strategy (and, by association, the federal government), even if they were entirely funded by philanthropic or community efforts?

Scientists have gone to great lengths to improve our knowledge about trends in threatened bird, mammal and plant species for which monitoring programs exist. However data for threatened species remains deficient, due to funding cuts for monitoring and associated infrastructure.

This means measuring progress on the strategy will be difficult, because we simply don’t have enough reliable data. And the strategy does not appear to remedy this situation with funding.

The strategy makes references to six important principles to guide decisions on which species are to be prioritised for assistance. These include how close a species is to extinction, a species’ ‘uniqueness’, the likelihood an intervention will work and whether the species is culturally significant. But these principles should not be applied in isolation from each other.

For example, it may be more cost efficient to save species with both a high chance of extinction and relatively cheap and effective interventions. But the most unique species may not be the cheapest to save, and the most endangered species may not be the species of greatest importance to one sector of the community.

So prioritisation may require trade-offs between different principles. There is no magic “one size fits all” solution, but excellent scientific guidance exists on how to keep this process objective, transparent and, most of all, repeatable.

The strategy acknowledges major drivers of biodiversity decline and extinction, including climate change, habitat destruction and pollution. However, nowhere is there an explicit declaration that to conserve or recover our species and environments we must tackle the underlying causes of these drivers.

The strategy also fails to acknowledge the key role legislation plays in reining in – or enabling – threats such as land clearing. An independent review earlier this year confirmed federal environment laws are failing abysmally. But fundamental recommendations stemming from the review, such as independent oversight and adequate resourcing, are not included in the strategy.

Without stronger laws and funding, the southern brown bandicoot’s future is uncertain.
Sarah Maclagan

A better deal for nature

To be effective, the strategy must chart a path to effective environmental law reform.

And saving our threatened species and ecosystems shouldn’t be seen as a cost, but rather a savvy investment.

Increased and targeted funding for on-ground actions, such as weed and pest animal control, species re-introductions, and Indigenous ranger programs, could generate many thousands of jobs. Such measures would also boost local economies and support industries such as tourism.

A 2019 study found Australia’s listed threatened species could be recovered for about A$1.7 billion a year.

The Morrison government recently announced it would spend A$7 billion setting up a military space division to better protect satellites from attack.

What’s our best defence for an uncertain future? We argue it’s ensuring Earth’s life support systems, including its remarkable species and landscapes, are also protected.

Euan Ritchie, Professor in Wildlife Ecology and Conservation, Centre for Integrative Ecology, School of Life & Environmental Sciences, Deakin University; Ayesha Tulloch, DECRA Research Fellow, University of Sydney, and Don Driscoll, Professor in Terrestrial Ecology, Deakin University

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

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.

Yellow wattle — 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.

Close-up of yellow flower — 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.

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.

A dead-looking gum tree on agricultural land — 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.

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.

Next time you see a butterfly, treasure the memory: scientists raise alarm on these 26 species

The bulloak jewel (*Hypochrysops piceatus*)
Michael Braby, Author provided

Michael F. Braby, Australian National University; Hayley Geyle, Charles Darwin University; Jaana Dielenberg, Charles Darwin University; Phillip John Bell, University of Tasmania; Richard V Glatz; Roger Kitching, Griffith University, and Tim R New, La Trobe UniversityIt might sound like an 18th century fashion statement, but the “pale imperial hairstreak” is, actually, an extravagant butterfly. This pale blue (male) or white (female) butterfly was once widespread, found in old growth brigalow woodlands that covered 14 million hectares across Queensland and News South Wales.

But since the 1950s, over 90% of brigalow woodlands have been cleared, and much of the remainder is in small degraded and weed infested patches. And with it, the butterfly numbers have dropped dramatically.

In fact, our new study has found it has a 42% chance of extinction within 20 years.

It isn’t alone. Our team of 28 scientists identified the top 26 Australian butterfly species and subspecies at greatest risk of extinction. We also estimated the probability that they will be lost within 20-years.

Without concerted new conservation effort, we’ll not only lose unique elements of Australia’s nature, but also the important ecosystem services these butterflies provide, such as pollination.

Only six are protected under law

We are now sounding the alarm as most species identified as at risk have little or no management underway to conserve them, and only six of the 26 butterflies identified are currently listed for protection under Australian law.

The Ptunarra Xenica is one of three at risk butterflies identified in Tasmania.
Simon Grove/Tasmanian Museum and Art Gallery

The good news is there’s still a very good chance of recovery for most of these species, but only with new targeted conservation effort, such as protecting habitat from clearing and weeds, better fire management and establishing more of the right caterpillar food plants.

Let’s meet a few at-risk butterflies

The butterflies identified are delightful and fascinating creatures, with intriguing lifecycles, including fussy food preferences, subterranean accommodation and intimate relationships with “servant” ants.

The Australian fritillary

Our most imperilled butterfly is the Australian fritillary, with a 94% chance of extinction within 20 years. Like many of our butterfly species, a major threat facing the fritillary is habitat loss and habitat change.

The swamps where the fritillary occur have been drained for farming and urbanisation. At remaining swamps, weeds smother the native violets the larvae depend on for food.

This is one of the last known photos of the Australian fritillary. If you see a fritillary, immediately contact the NSW Department of Planning Industry and Environment.
Garry Sankowsky

No one has managed to collect or take a photo of a fritillary in two decades, although a butterfly expert observed a single individual flying near Port Macquarie in 2015.

It might already be extinct, but as it was once quite widespread at swampy areas along 700 kilometres of coastal Queensland and NSW, we have hope there are still some out there.

The fritillary has impressive jet black caterpillars with a vibrant orange racing stripe and large spikes along their back, which transform into stunning orange and black butterflies.

Anyone who thinks they have seen a fritillary should record the location, try to photograph it and the site and immediately contact the NSW Department of Planning Industry and Environment.

The fritillary is among many butterflies with specific diets. And these preferences can make species vulnerable to environmental changes such as vegetation clearing, weed invasions and fires.

The small bronze azure

Caterpillars of the small bronze azure — found on Kangaroo Island (and a few other patches in South Australia and Victoria) — only eat common sourbush.

Following the extensive 2020 fires, the butterfly hasn’t been found in areas where the sourbush burnt. Luckily, it’s been found in small patches of unburnt vegetation, so for now it’s hanging in there.

The small bronze azure has not been re-found in parts of Kangaroo Island where common sourbush burnt in the January 2020 fires.
Richard Glatz

Like many butterflies, the lifecycle of the small bronze azure is enmeshed with a specific species of ant.

By day the butterfly larvae shelter underground in sugar ant (Camponotus terebrans) nests, then at night they’re escorted up by the ants to feed on the sourbush. For their care the ants are rewarded by a sugary secretion the caterpillars produce.

The eastern bronze azure

Some relationships with ants are even more unusual. Kangaroo Island’s other imperilled species — the eastern bronze azure — stays underground in sugar ant nests for 11 straight months. We don’t yet know what they eat.

Grey butterfly on a rock — An eastern bronze azure (*Ogyris halmaturia*) on Kangaroo Island. Their colouring is excellent camouflage on branches.
Michael Braby

In a macabre twist, they may be eating their hosts — the ants or the ant larvae. So why the ants carry them down and look after them is also a mystery.

It might be for sugary secretions, like with the small bronze azure, but the caterpillars could also be using chemical trickery, mimicking the scent of ant larvae to fool the ants.

Adults of the eastern bronze azure emerge only to flutter about for a few weeks in November, so at the time of the Kangaroo Island fires in January the entire population was safely underground in ant nests. And as the larvae don’t come up to feed on plants, they weren’t impacted by the loss of vegetation.

Orange and black butterfly on a green leaf — This is the black grass-dart, found near Coffs Harbour. The caterpillars eat Floyd’s grass (*Alexfloydia repens*) which is listed as endangered in NSW.
Mick Andren

It’s not too late to save them

By raising awareness of these butterflies and the risks they face, we aim to give governments, conservation groups and the community time to act to prevent their extinctions.

Local landowners and Landcare groups have already been playing a valuable role in recovery actions for several species, such as planting the right food plants for the Australian fritillary around Port Macquarie, and for the Bathurst copper.

Brown and green butterfly on a log — The Bathurst copper in NSW is benefiting from community planting of its food plant sweet bursaria.
Tessa Barratt

Indeed, most of the identified at-risk species occur across a mix of land types, including conservation, public and private land. In most cases, conservation reserves alone aren’t enough to ensure the long-term survival of the species.

Many landowners don’t realise they’re important custodians of such rare and threatened butterflies, and how important it is not to clear remaining patches of remnant native vegetation on their properties and adjoining road reserves.

People wanting to learn more about the butterfly species near them can use the free Butterflies Australia app to look up photos and information. You can also be a citizen scientist by recording and uploading sightings on the app.

Michael F. Braby, Associate Professor, Australian National University; Hayley Geyle, Research Assistant, Charles Darwin University; Jaana Dielenberg, University Fellow, Charles Darwin University; Phillip John Bell, University Associate, School of Natural Sciences, University of Tasmania; Richard V Glatz, Associate research scientist; Roger Kitching, Emeritus Professor, Griffith University, and Tim R New, Retired: Emeritus Professor in Zoology, La Trobe University

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

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.

Banded dotterel chick in a snad nest — 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.

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, a reptile found only in New Zealand. — 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.

Looking up into the canopy of beech trees. — 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.

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).

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.

Satellite images of New Zealand, showing two years and the impact of drought. — 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.

Mangroves from space: 30 years of satellite images are helping us understand how climate change threatens these valuable forests

Travel Sourced, Pixabay.
Travel Sourced, Pixabay, CC BY-SA

Nicolás Younes Cárdenas, James Cook University; Karen Joyce, James Cook University, and Stefan W Maier, James Cook UniversityAustralia is home to around 2% of the world’s mangrove forests and is the fifth most mangrove-forested country on Earth. Mangroves play a crucial role in the ecosystem thanks to the dizzying array of plants, animals and birds they feed, house and protect.

Mangrove forests help protect coastal communities from cyclones and storms by absorbing the brunt of a storm’s energy. They help our fight against climate change by storing vast amounts of carbon that would otherwise be released as greenhouse gases.

In other words, mangroves are some of our most precious ecosystems. Despite their importance, there is much we don’t know about these complex wetland forests. For example, when does their growing season start? And, how long does it last?

Usually, answering these types of questions requires frequent data collection in the field, but that can be costly and time-consuming. An alternative is to use satellite images. In the future, this will allow us to track the impacts of climate change on mangroves and other forests.

Mangroves flowering and fruiting in Townsville, QLD. — Mangroves play a crucial role in the ecosystem thanks to the dizzying array of plants, animals and birds they feed, house and protect.
Nicolas Younes

What is phenology?

Our research used satellite images to study the life cycles of mangrove forests in the Northern Territory, Queensland, and New South Wales. We compared the satellite images with field data collected in the 1980s, 1990s and 2000s, and found a surprising degree of variation in mangrove life cycles.

We’re using the phrase life cycle, but the scientific term is “phenology”. Phenology is the study of periodic events in the life cycles of plants and animals. For example, some plants flower and fruit during the spring and summer, and some lose their leaves in autumn and winter.

Phenology is important because when plants are growing, they absorb carbon from the atmosphere and store it in their leaves, trunks, roots, and in the soil. As phenology is often affected by environmental conditions, studying phenology helps us understand how climate change is affecting Australian ecosystems such as mangrove forests.

So how can we learn a lot in a short amount of time about mangrove phenology? That’s where satellite imagery comes in.

How we use satellites to study mangrove phenology

Satellites are an excellent tool to study changes in forest health, area, and phenology. Some satellites have been taking images of Earth for decades, giving us the chance to look back at the state of mangrove forests from 30 years ago or more.

You can think of satellite images much like the photo gallery in your smartphone: you can see many of your family members in a single image, and you can see how everyone grows and “blooms” over time. In the case of mangroves, we can see different regions and species in a single satellite image, and we can use past images to study the life cycles of mangrove forests.

For example, satellite images depicted below, which use data from the Australian government’s National Maps website, show how mangroves forests have changed in the Kimberley region of Western Australia between 1990 and 2019. You can see how the mangrove forest has reduced in some areas, but expanded in others. Overall, this mangrove forest seems to be doing pretty well thanks in large part to the fact this area has a reasonably small human population.

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Images: NationalMap/Data61

Our study of satellite images of mangrove forests in the Northern Territory, Queensland, and New South Wales – and how they compared with data collected on the ground – found not all mangroves have the same life cycles.

For instance, many mangrove species grow new leaves only once per year, while other species grow new leaves twice a year. These subtle, but important differences will allow us to track the impacts of climate change on mangroves and other forests.

Mangroves at different growth stages in Bushland Beach, QLD — Satellite images of mangrove forests reveal not all mangroves have the same life cycles. Here we see mangroves at different growth stages.
Nicolas Younes

How climate change affects mangrove phenology

Climate change is changing the phenology of many forests, causing them to flower and fruit earlier than expected.

Science cannot yet tell us exactly how mangrove phenology will be affected by climate change but the results could be catastrophic. If mangroves flower or fruit earlier than expected, pollinators such as bats, bees and birds may starve or move to a different forests. Without pollinators, mangroves may not reproduce and can die.

The next step in our research is to figure out how climate change is affecting the life cycles of mangroves. To do this, we will use satellite images of mangroves across Australia and factor in data on temperature and rainfall.

We think rising temperatures are causing longer periods of leaf growth, a theory we plan to test by studying data from now with satellite images from the 80s and 90s.

Satellite monitoring can’t do it all

Satellites can tell us a lot about how a mangrove forest is faring. For example, satellite images captured a dieback event (depicted below, using data from the Australian government’s National Maps website) that happened between 2015 and 2016, when around 7,400 hectares of mangroves died in the Gulf of Carpentaria due to drought and unusually high air and sea temperatures.

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Images: NationalMap/Data61

But satellite monitoring is not enough on its own and cannot capture the detail you can get on the ground. For example, satellites cannot capture the flowering or fruiting of mangroves because flowers are often too small and fruits are often camouflaged. Also, satellites cannot capture what happens under the canopy.

It is also important to recognise the work of researchers on the ground. Ground data allows us to validate or confirm the information we see in satellite images. When we noted some mangrove forests were growing leaves twice per year, we validated this observation with field data, and confirmed with experts in mangrove ecosystems. Field data is crucial to understand the life cycles of ecosystems worldwide and how forests are responding to changes in the climate.

A bird in a wetlands. — Wetlands, including mangroves, are some of our most precious ecosystems.
Shutterstock

Nicolás Younes Cárdenas, Postdoctoral research fellow, James Cook University; Karen Joyce, Senior Lecturer – Remote sensing and spatial information, James Cook University, and Stefan W Maier, Adjunct Research Fellow, James Cook University

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

Life on the hidden doughnuts of the Great Barrier Reef is also threatened by climate change

A sea cucumber living on the Great Barrier Reef inter-reef seafloor.
Kent Holmes/Nature Ecology and Evolution, Author provided

Mardi McNeil, Queensland University of Technology; Andrew Hoey, James Cook University; Jody Webster, University of Sydney, and Luke Nothdurft, Queensland University of Technology

Mention the Great Barrier Reef, and most people think of the rich beauty and colour of corals, fish and other sea life that are increasingly threatened by climate change.

But there is another part of the Great Barrier Reef that until recently was largely hidden and under-explored.

In the northern section of the Great Barrier Reef Marine Park there are large Halimeda algal habitats called bioherms (also known as doughnuts because of their shape).

They are constructed by a type of algae (Halimeda) with a limestone skeleton. The tops of the bioherms are carpeted by a living meadow of the algae, yet much of the plant community includes other types of green, red and brown algae and some seagrasses.

A type of green seaweed. — *Halimeda* is a genus of green macroalgae (seaweed).
Mardi McNeil, Author provided

The bioherms cover an area greater than 6,000km², more than twice the area of shallow coral reefs.

Several maps showing the location of the _Halimeda_ bioherms. — The distribution of *Halimeda* bioherms in the Great Barrier Reef.
Figshare/Mardi McNeil, CC BY

Scientists have known for decades of this unusual inter-reef seafloor habitat that lies between the coast and the outer barrier reefs. But they’ve never investigated the diversity of marine life that lives there, until now.

In a new study published today in Nature Ecology and Evolution, scientists examined the community of plants and animals that inhabit these unique areas.

Let’s go deeper

Most studies of tropical marine biodiversity come from shallow coastal and coral reef habitats. We know a great deal about the biodiversity of these parts of the Great Barrier Reef.

But beyond the vision of scuba divers, deeper inter-reef habitats on the shelf, such as the bioherms, have been largely under-explored.

In our study, we used a dataset of all the plants and animals recorded from the bioherms and surrounding seafloor habitats. The data came from the Seabed Biodiversity Project, a large study published back in 2007 of the inter-reef biodiversity in the Great Barrier Reef World Heritage Area.

What we found was surprising. An exceptional diversity of marine life and a distinct community was found to be living on the bioherms.

A diverse community

The biodiversity of marine life was up to 76% higher on the bioherms than the surrounding inter-reef habitats. Species richness was especially high for plants and invertebrates.

The average number of fish species per site was about the same in both Halimeda and non-Halimeda habitats. In total, 265 species of fish were observed in the bioherms, including sharks and rays.

Overall, more than 1,200 species of animals were recorded from the bioherms. The majority of these (78%) are invertebrates.

A feather star invertebrate. — Most of the animals living on the *Halimeda* bioherms are invertebrates, such as this feather star.
Mardi McNeil, Author provided

A distinct community

The composition of plant and animal communities on the bioherms was also distinctly different to the surrounding inter-reef areas.

Some 40% of bioherm species were unique to that habitat in the study area. The community included many sponges, snails and slugs, crabs and shrimps, brittle stars, sea urchins and sea cucumbers.

The fish community on the bioherms was also distinct from surrounding habitats. The two-spot wrasse, threadfin emperor and black-banded damselfish were particularly common.

A small black fish with a yellow tail and a white band near its neck. — A yellowtail angelfish (*Chaetodontoplus meredithi*) seen in coral waters of the Great Barrier Reef.
Sascha Schultz/iNaturalist.org/FishofAustralia, CC BY-NC

Most interesting about the bioherm fish community was the occurrence of some species such as the yellowtail angelfish generally thought to live mostly on coral reefs. Some of these reef-associated fishes have been increasingly observed in a range of non-reef habitats.

These multi-habitat users may be using the bioherms for shelter, feeding, spawning or as nursery grounds. Understanding the connections between shallow coral reefs and deeper bioherms is important to better understand how the reef and inter-reef habitats function.

An unusual habitat

The Halimeda bioherms are arguably the weirdest habitat in the Great Barrier Reef.

Recent high-resolution seafloor mapping using airborne lasers revealed the bioherms form a seafloor that looks like fields of giant doughnuts 20 metres high and 200 metres across.

The doughnuts are the connected circles on the seafloor in the yellow/green bioherm part. They look quite small but each circle is about 200 metres across.

The tops of the bioherms lie some 25-30 metres below the surface, so can’t be seen from boats passing over.

Deeper water and the remote location has meant the bioherms have been mostly invisible to marine biologists that work on the nearby shallow coral reefs.

Under threat from climate change

We are only just beginning to understand the importance of Halimeda bioherms as a habitat to support biodiversity in the Great Barrier Reef.

But just as the rest of the Great Barrier Reef is likely to be impacted by the effects of climate change, so too are the bioherms.

Potential threats to the bioherms include marine heating, ocean acidification and changes to circulation patterns.

It has been more than 15 years since the inter-reef Seabed Biodiversity Project. The five-yearly Great Barrier Reef Outlook Report says little is known about any ecological trends in the bioherm habitat.

Our new study provides a baseline of the biodiversity of Halimeda bioherms at a single point in time. But questions remain about the present state of this ecosystem and its resilience on short and long-term physical and biological cycles.

Long-term monitoring of these unique and hidden habitats is critical to more fully understand the overall health of the Great Barrier Reef.

Mardi McNeil, Postdoctoral researcher, Queensland University of Technology; Andrew Hoey, Senior Research Fellow, James Cook University; Jody Webster, Professor of Marine Geoscience, University of Sydney, and Luke Nothdurft, Senior Lecturer – Earth Science, Queensland University of Technology

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

Plastic in the ocean kills more threatened albatrosses than we thought

Richelle Butcher, Massey University; Britta Denise Hardesty, CSIRO, and Lauren Roman, CSIRO

Plastic in the ocean can be deadly for marine wildlife and seabirds around the globe, but our latest study shows single-use plastics are a bigger threat to endangered albatrosses in the southern hemisphere than we previously thought.

You may have heard of the Great Pacific garbage patch in the northern Pacific, but plastic pollution in the southern hemisphere’s oceans has increased by orders of magnitude in recent years.

We examined the causes of death of 107 albatrosses received by wildlife hospitals and pathology services in Australia and New Zealand and found ocean plastic is an underestimated threat.

Plastic drink bottles, disposable utensils and balloons are among the most deadly items.

Albatrosses are some the world’s most imperiled seabirds, with 73% of species threatened with extinction. Most species live in the southern hemisphere.

We estimate plastic ingestion causes up to 17.5% of near-shore albatross deaths in the southern hemisphere and should be considered a substantial threat to albatross populations.

Magnificent ocean wanderers

Albatrosses spend their entire lives at sea and can live for more than 70 years. They return to land only to reunite with their mate and raise a single chick during the warmer months.

Although the world’s largest flying birds are rarely seen from land, human activities are driving nearly three quarters of albatross species to extinction.

An albatross flying across the ocean. — The great albatrosses are the largest flying birds in the world, circumnavigating the southern oceans in search of food.
Lauren Roman, Author provided

Each year, thousands of albatrosses are caught as unintended bycatch and killed by fishing boats. Introduced rats and mice eat their chicks alive on remote islands and the ocean where they spend their lives is becoming increasingly warmer and filled with plastic.

Young Laysan albatrosses with their bellies full of plastic are not just a tragic tale from the remote northern Pacific. Albatrosses are dying from plastic in the southern oceans, too.

When a Royal albatross recently died in care at Wildbase Hospital after eating a plastic bottle, it was not an isolated incident.

Single-use plastics hit albatrosses close to home

A veterinarian treating a light-mantled albatross — Veterinarian Baukje Lenting treating a light-mantled albatross at The Nest Te Kōhanga at Wellington Zoo.
Wellington Zoo, Author provided

Eighteen of the world’s 22 albatross species live in the southern hemisphere, where plastic is currently considered a lesser threat. But the amount of discarded plastic is increasing every year, mostly leaked from towns and cities and accumulating near the shore.

Single-use items make up most of the trash found on coastlines around the world. Seven of the ten most common items — drink bottles, food wrappers and grocery bags — are made of plastic.

When albatrosses are found struggling near the shore in New Zealand, they are delivered to wildlife hospitals such as Wildbase Hospital and The Nest Te Kōhanga. A recent spate of plastic-linked deaths spurred us to dig a little deeper into the risk of plastic pollution to these magnificent ocean wanderers.

A thousand cuts: plastic and other threats

Of the 107 albatrosses of 12 species we examined, plastic was the cause of death in half of the birds that had ingested it. In the cases we examined, plastic deaths were more common than fisheries-related deaths or oiling.

We compared these cases with data on plastic ingestion and fishery interaction rates from other studies. Based on our findings, we used statistical methods to estimate how many albatrosses were likely to eat plastic and might die from ingesting it, and how these figures compared to other major threats such as fisheries bycatch.

We found that in the near-shore areas of Australia and New Zealand, the ingestion of plastic is likely to cause about 3.4% of albatross deaths. In more polluted near-shore areas, such as those off Brazil, we estimate plastic ingestion causes 17.5% of all albatross deaths.

Because albatrosses are highly migratory, even those birds that live in less polluted areas are at risk as they wander the global ocean, travelling to polluted waters. Our results suggest the ingestion of plastic is at least of equivalent concern as long-line fishing in near-shore areas.

For threatened and declining albatross species, these rates of additional mortality are a serious concern and could result in further population losses.

Deadly junk food for marine life

Balloon fragments found in the stomach on an endangered albatross — The remains of two balloons in the stomach of an endangered grey-headed albatross.
Lauren Roman, Author provided

Not all types of plastic are equally deadly when eaten. Albatrosses can regurgitate many of the indigestible items they eat.

Soft plastic and rubber items (such as latex balloons), in particular, can be deadly for marine animals because they often become trapped in the gut and cause fatal blockages, leading to a long, slow death by starvation. Plastic is difficult to see with common scanning techniques, and gut blockages often remain undetected.

A plastic bottle found in the stomach of an albatross — A 500ml plastic bottle and balloon fragments were found in the stomach of a southern royal albatross which died in care at Wildbase Hospital.
Stuart Hunter, Author provided

Albatrosses like to eat squid, and inexperienced young birds are especially prone to mistaking balloons and other plastic for food, with potentially lethal consequences.

We recommend that wildlife hospitals, carers and biologists consider gastric obstruction when sick albatrosses are presented. Our publication includes a checklist to help in the detection of gastric blockages.

Global cooperation to reduce leakage of plastic items into the ocean — such as the Basel Convention and the recommendations by the High Level Panel for a Sustainable Ocean Economy — are first steps towards preventing unnecessary deaths of marine animals.

Stronger adherence to multilateral agreements, such as the Agreement on the Conservation of Albatrosses and Petrels which aims to reduce the impact of activities known to kill albatrosses, would help prevent the decline of breeding populations to unsustainably low levels.

If populations fall to critically endangered levels, intensive remediation including the expansion of chick and nest protection programmes, invasive species eradication and seabird translocations, may be required to prevent species extinction.

We would like to acknowledge our New Zealand and Australian colleagues who contributed to this research project. Veterinarians Baukje Lenting and Phil Kowalski care for injured seabirds and other wildlife at The Nest Te Kōhanga at Wellington Zoo. Veterinarian Megan Jolly cares for injured wildlife at Wildbase Hospital and vet pathologist Stuart Hunter provides a nationwide wildlife pathology service at Wildbase pathology at Massey University. David Stewart conducts threatened species research and monitoring at the Queensland state government’s Department of Environment and Science.

Richelle Butcher, Veterinary Resident at Wildbase, Massey University; Britta Denise Hardesty, Principal Research Scientist, Oceans and Atmosphere Flagship, CSIRO, and Lauren Roman, Postdoctoral Researcher, Oceans and Atmosphere, CSIRO

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

A new 3D koala genome will aid efforts to defend the threatened species

Parwinder Kaur, University of Western Australia

Koalas are unique in the animal kingdom, living on a eucalyptus diet that would kill other creatures and drinking so little their name comes from the Dharug word gula, meaning “no water”. Today, many koala populations across Australia are in decline, due to habitat destruction caused by agriculture, urbanisation, droughts and bushfires intensified by climate change, and diseases such as chlamydia and koala retrovirus.

Genetic information can play a key role in the effort to conserve koalas and other species. A detailed map of the koala genome is vital to understanding their susceptibility to disease, their genetic diversity, and how they may respond to new environmental pressures.

We have created a new “chromosome-length” sequence of the koala genome, which will allow researchers to study its three-dimensional structure and understand its evolution.

A unique creature under threat

The modern koala is the only living representative of the marsupial family Phascolarctidae, a family that once included several genera and species. During the Oligocene and Miocene epochs (from 34 to 5 million years ago), the ancestors of modern koalas lived in rainforests and didn’t eat only leaves.

During the Miocene, the Australian continent began drying out, leading to the decline of rainforests and the spread of open eucalyptus woodlands. Koalas evolved several adaptations that allowed them to live on a specialised eucalyptus diet. This specialisation makes them picky eaters, so they’re very prone to habitat loss.

Koalas are listed as a vulnerable species by the International Union for Conservation of Nature. It was hunted heavily in the early 20th century for its fur, and large-scale cullings in Queensland resulted in public outcry, initiating a movement to protect the species. Sanctuaries were established, and koalas whose habitat was disappearing were relocated.

Koalas are particularly vulnerable to bushfires; they are slow moving and eucalypt trees are very flammable. They instinctively seeks refuge in higher branches, exposing them to intense heat and flames. Bushfires also fragment the animal’s habitat, which restricts their movement and leads to population decline and loss of genetic diversity.

Piecing together the puzzle

The koala genome was first sequenced in 2013. This was only the first step in understanding koala genetics — akin to finding all the pieces of the puzzle, but being unsure how to put them all together into the meaningful patterns of genes and chromosomes.

Our new chromosome-length assembly follows the work of others, especially the Koala Genome Consortium and the Koala Genome Project led by Australian geneticist Rebecca Johnson. It is based on a draft by the Earlham Institute in the UK.

We used big-data sequencing methods such as Hi-C, 3D-DNA and Juicebox Assembly Tools courtesy of DNA Zoo labs to create our chromosome-length assembly.

We organised the genome into 8 chromosomes, a great improvement on the draft of 1,907 fragments we began with.

Vital for conservation

A high-quality genome sequence is essential if we want to bring genetic insights to conservation management initiatives. Some 200 Australian vertebrate species currently have species recovery plans, and 80% of those plans include genome-based actions. However, only 15% of those species have any genomic data available.

Our chromosome-length koala genome assembly enables a highly detailed 3D view of the genome architecture for koala. It is easier to use than earlier genomes, and means conservation management initiatives will have fast, cost-effective and reliable analysis options available.

This will give us insights into koalas’ genetic susceptibility to diseases like koala retrovirus (KoRV) and chlamydia. It may also form a basis for innovative vaccines. What’s more, it can be used in new conservation management strategies that aim to diversify the koala gene pool.

Parwinder Kaur, Associate Professor | Director, DNA Zoo Australia, University of Western Australia

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

So, why should we care about these bats anyway?

1. Pacific sheath-tailed bat

2. Montane monkey-faced bat

3. Ornate flying-fox

4. Fijian free-tailed bat

Where do we go from here?

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How did the strategy perform?

Falling short on feral cats

Priority species: how did we do?

What must change

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First, the good news

But challenges remain

A better deal for nature

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What’s driving the loss?

On the brink

So how can we protect them?

Now we need the political will

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Only six are protected under law

Let’s meet a few at-risk butterflies

It’s not too late to save them

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Complex interplay between many threats

How climate change affects biodiversity

Indirect effects of climate change

Climate change is here now

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What is phenology?

How we use satellites to study mangrove phenology

How climate change affects mangrove phenology

Satellite monitoring can’t do it all

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Let’s go deeper

A diverse community

A distinct community

An unusual habitat

Under threat from climate change

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Magnificent ocean wanderers

Single-use plastics hit albatrosses close to home

A thousand cuts: plastic and other threats

Deadly junk food for marine life

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A unique creature under threat

Piecing together the puzzle

Vital for conservation

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