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.


Author provided, Author provided

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.

Black caterpillar
Australian fritillary caterpillars are black with a distinctive orange stripe and spikes.
Garry Sankowsky

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.




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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.




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The Conversation


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.




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


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.

The alpine parrot kea
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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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.The Conversation

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.

A mangrove forest.
The next step in our research is to figure out how climate change is affecting the life cycles of mangroves.
Shutterstock

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.The Conversation

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.




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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.




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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.The Conversation

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


Lauren Roman, Author provided

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.




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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.




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Plastic poses biggest threat to seabirds in New Zealand waters, where more breed than elsewhere


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.




Read more:
We need a legally binding treaty to make plastic pollution history


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.The Conversation

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.




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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.




Read more:
To save koalas from fire, we need to start putting their genetic material on ice


The Conversation


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.

It’s not too late to save them: 5 ways to improve the government’s plan to protect threatened wildlife



Numbats are among 20 mammals on the federal government’s priority list.
Shutterstock

Euan Ritchie, Deakin University; Ayesha Tulloch, University of Sydney; Don Driscoll, Deakin University; Megan C Evans, UNSW, and Tim Doherty, University of Sydney

Australia’s Threatened Species Strategy — a five-year plan for protecting our imperilled species and ecosystems — fizzled to an end last year. A new 10-year plan is being developed to take its place, likely from March.

It comes as Australia’s list of threatened species continues to grow. Relatively recent extinctions, such as the Christmas Island forest skink, Bramble Cay melomys and smooth handfish, add to an already heavy toll.

Red handfish (Thymichthys politus), cousin of the recently extinct smooth handfish, are critically endangered. They’re small, bottom-dwelling fish that tend to ‘walk’ on their pectoral and pelvic fins rather than swim.
CSIRO Science Image, CC BY-SA

Now, more than ever, Australia’s remarkable species and environments need strong and effective policies to strengthen their protection and boost their recovery.

So as we settle into the new year, let’s reflect on what’s worked and what must urgently be improved upon, to turn around Australia’s extinction crisis.




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How effective was the first Threatened Species Strategy?

The Threatened Species Strategy is a key guiding document for biodiversity conservation at the national level. It identifies 70 priority species for conservation, made up of 20 birds, 20 mammals and 30 plants, such as the plains-wanderer, malleefowl, eastern quoll, greater bilby, black grevillea and Kakadu hibiscus.

These were considered among the most urgent in need of assistance of the more than 1,800 threatened species in Australia.

The strategy also identifies targets such as numbers of feral cats to be culled, and partnerships across industry, academia and government key to making the strategy successful.

The original strategy (2015-20) was eagerly welcomed for putting the national spotlight on threatened species conservation. It has certainly helped raise awareness of its priority species.

However, there’s little evidence the strategy has had a significant impact on threatened species conservation to date.

The midterm report in 2019 found only 35% of the priority species (14 in total) had improving trajectories compared to before the strategy (pre-2015). This number included six species — such as the brush-tailed rabbit-rat and western ringtail possum — that were still declining, but just at a slower rate.

Threatened Species Index trends for mammals (left) and birds (right) from 2000 to 2017. The index and y axes show the average change in populations (not actual population numbers) through time.
The Theatened Species Recovery Hub, Author provided

On average, the trends of threatened mammal and bird populations across Australia are not increasing.

Other targets, such as killing two million feral cats by 2020, were not explicitly linked to measurable conservation outcomes, such as an increase in populations of threatened native animals. Because of this, it’s difficult to judge their success.




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


What needs to change?

The previous strategy focused very heavily on feral cats as a threat and less so on other important and potentially compounding threats, particularly habitat destruction and degradation.

Targets from the first Threatened Species Strategy.
Department of Agriculture, Water and the Environment

For instance, land clearing has contributed to a similar number of extinctions in Australia (62 species) as introduced animals such as feral cats (64).

In fact, 2018 research found agricultural activities affect at least 73% of invertebrates, 82% of birds, 69% of amphibians and 73% of mammals listed as threatened in Australia. Urban development and climate change threaten up to 33% and 56% of threatened species, respectively.




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Other important threats to native Australian species include pollution, feral herbivores (such as horses and goats), very frequent or hot bushfires and weeds. Buffel grass was recently identified as a major emerging threat to Australia’s biodiversity, with the risk being as high as the threat posed by cats and foxes.

Five vital improvements

We made a submission to the Morrison government when the Threatened Species Strategy was under review. Below, we detail our key recommendations.

1. A holistic and evidence-based approach encompassing the full range of threats

This includes reducing rates of land clearing — a major and ongoing issue, but largely overlooked in the previous strategy.

A Leadbeater's possum peers out from behind a tree trunk.
Leadbeater’s possums are critically endangered. Their biggest threat is the destruction of hollow-bearing trees.
Shutterstock

2. Formal prioritisation of focal species, threats and actions

The previous strategy focused heavily on a small subset of the more than 1,800 threatened species and ecosystems in Australia. It mostly disregarded frog, reptile, fish and invertebrate species also threatened with extinction.

To reduce bias towards primarily “charismatic” species, the federal government should use an evidence-based prioritisation approach, known as “decision science”, like they do in New South Wales, New Zealand and Canada. This would ensure funds are spent on the most feasible and beneficial recovery efforts.

3. Targets linked to clear and measurable conservation outcomes

Some targets in the first Threatened Species Strategy were difficult to measure, not explicitly linked to conservation outcomes, or weak. Targets need to be more specific.

For example, a target to “improve the trajectory” of threatened species could be achieved if extinction is occurring at a slightly slower rate. Alternatively, a target to “improve the conservation status” of a species is achieved if new assessments rate it as “vulnerable” rather than “endangered”.

The ant plant (Myrmecodia beccarii) is one of the 30 plants on the federal government’s list of priority species. It is an ‘epiphyte’ (grows on other plants), and is threatened by habitat loss, invasive weeds, and removal by plant and butterfly collectors.
Dave Kimble/Wikimedia, CC BY-SA

4. Significant financial investment from government

Investing in conservation reduces biodiversity loss. A 2019 study found Australia’s listed threatened species could be recovered for about A$1.7 billion per year. This money could be raised by removing harmful subsidies that directly threaten biodiversity, such as those to industries emitting large volumes of greenhouse gases.

The first strategy featured a call for co-investment from industry. But this failed to attract much private sector interest, meaning many important projects aimed at conserving species did not proceed.

5. Government leadership, coordination and policy alignment

The Threatened Species Strategy should be aligned with Australia’s international obligations such as the United Nation’s Sustainable Development Goals and the federal Environment Protection and Biodiversity Conservation Act 1999 (which is also currently being reviewed). This will help foster a more coherent and efficient national approach to threatened species conservation.

The biggest threat to the critically endangered swift parrot is the clearing of their foraging and breeding habitat.
Shutterstock

There are also incredible opportunities to better align threatened species conservation with policies and investment in climate change mitigation and sustainable agriculture.

The benefits of investing heavily in wildlife reach beyond preventing extinctions. It would generate many jobs, including in regional and Indigenous communities.

Protecting our natural heritage is an investment, not a cost. Now is the time to seize this opportunity.




Read more:
Scientists re-counted Australia’s extinct species, and the result is devastating


The Conversation


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; Don Driscoll, Professor in Terrestrial Ecology, Deakin University; Megan C Evans, Lecturer and ARC DECRA Fellow, UNSW, and Tim Doherty, ARC DECRA Fellow, University of Sydney

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

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


Ayesha Tulloch, University of Sydney; Elisa Bayraktarov, The University of Queensland; Hugh Possingham, The University of Queensland; Jaana Dielenberg, Charles Darwin University; Jennifer Silcock, The University of Queensland; Micha Victoria Jackson, The University of Queensland, and Nathalie Butt, The University of Queensland

When it comes to threatened species, charismatic animals usually get the most attention. But many of Australia’s plants are also in grave danger of extinction, and in many cases, the problem is getting worse.

New Australia-first research shows the population sizes of our threatened plants fell by almost three-quarters, on average, between 1995 and 2017. The findings were drawn from Australia’s 2020 Threatened Species Index, which combines data from almost 600 sites.

Plants are part of what makes us and our landscapes unique. They are important in their own right, but also act as habitat for other species and play critical roles in the broader ecosystem.

This massive data-crunching exercise shows that a lot more effort is needed if we want to prevent plant extinctions.

Plants, such as WA’s Endangered Foote’s grevillea, make our landscape unique.
Andrew Crawford / WA Department of Biodiversity Conservation and Attractions

Spotlight on plants

Australia’s plant species are special – 84% are found nowhere else in the world. The index shows that over about 20 years up to 2017, Australia’s threatened plant populations declined by 72%. This is faster than mammals (which declined by about a third), and birds (which declined by about half). Populations of trees, shrubs, herbs and orchids all suffered roughly similar average declines (65-75%) over the two decades.

Of the 112 species in the index, 68% are critically endangered or endangered and at risk of extinction if left unmanaged. Some 37 plant species have gone extinct since records began, though many others are likely to have been lost before scientists even knew they existed. Land clearing, changed fire regimes, grazing by livestock and feral animals, plant diseases, weeds and climate change are common causes of decline.




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


Vulnerable plant populations reduced to small areas can also face unique threats. For example, by the early 2000s Foote’s grevillea (Grevillea calliantha) had dwindled to just 27 wild plants on road reserves. Road maintenance activities such as mowing and weed spraying became a major threat to its survival. For other species, like the button wrinklewort, small populations can lead to inbreeding and a lack of genetic diversity.

Fire, interrupted

Threatened plant conservation in fire-prone landscapes is challenging if a species’ relationship with fire is not known. Many Australian plant species require particular intensities or frequencies of burns for seed to be released or germinate. But since European settlement, fire patterns have been interrupted, causing many plant populations to decline.

Three threatened native pomaderris shrubs on the NSW South Coast are a case in point. Each of them – Pomaderris adnata, P. bodalla and P. walshii – have failed to reproduce for several years and are now found only in a few locations, each with a small number of plants.

Experimental trials recently revealed that to germinate, the seeds of these pomaderris species need exposure to hot-burning fires (or a hot oven). However they are now largely located in areas that seldom burn. This is important knowledge for conservation managers aiming to help wild populations persist.

Endangered sublime point pomaderris (Pomaderris adnata) requires high fire temperatures to germinate.
Jedda Lemmon /NSW DPIE, Saving our Species

Success is possible

A quarter of the species in the threatened plant index are orchids. Orchids make up 17% of plant species listed nationally as threatened, despite comprising just 6% of Australia’s total plant species.

The endangered coloured spider-orchid (Caladenia colorata) is pollinated only by a single thynnine wasp, and relies on a single species of mycorrhizal fungi to germinate in the wild.

Yet even for such a seemingly difficult species, conservation success is possible. In one project, scientists from the Royal Botanic Gardens Victoria, aided by volunteers, identified sites where the wasp was still naturally present. More than 800 spider orchid plants were then propagated in a lab using the correct symbiotic fungus, then planted at four sites. These populations are now considered to be self-sustaining.

In the case of Foote’s grevillea, a plant translocation program has established 500 plants at three new sites, dramatically improving the species’ long-term prospects.

Orchid flower
The coloured spider orchid, found in South Australia and Victoria, is endangered.
Noushka Reiter/Royal Botanic Gardens Victoria

But we aren’t doing enough

Both federal environment laws and the national threatened species strategy are under review. Submissions by research institutions and others have noted a lack of data, recovery actions and conservation funding for plants.

Our research found threatened plant populations at managed sites suffered declines of 60% on average, compared to 80% declines at unmanaged sites. This shows that while management is beneficial, it is not preventing overall declines.

New data on threatened species trends are added to the plant index each year, but many species are missing from the index because they aren’t being monitored.




Read more:
Australia’s threatened birds declined by 59% over the past 30 years


Monitoring of threatened species is undertaken by government and non-government groups, community groups, Indigenous organisations, citizen scientists, researchers and individuals. Without it, we have no idea if species are recovering or heading unnoticed towards extinction.

Woman measuring the height of a plant
Monitoring is essential to know if conservation actions are working.
Rebecca Dillon / WA Department of Biodiversity Conservation and Attractions

Australia has about 1,800 threatened species. Of these, 77% – or 1,342 species – are plants. However the index received monitoring data for only 10% of these plants, compared to 35% of threatened birds, which make up only 4% of threatened species.

If you’re keen to get involved in plant monitoring, it involves just a few simple steps:

  • find a local patch with a threatened plant species

  • revisit it once or twice a year to count the number of individuals in a consistent, well-defined area

  • use the same method and the same amount of effort each visit

  • take great care to not disturb the plant or its habitat when looking for it

  • contribute your data to the index.

Saving Australia’s flora

Australia must urgently change the way we prioritise conservation actions and enact environment laws, if we hope to prevent more plant extinctions.

Critical actions include stopping further habitat loss and more funding for recovery actions as well as extinction risk assessments. It is important that these assessments adhere to consistent criteria. This is something the common assessment method, agreed to by all states and territories, seeks to achieve.

Finally, more funding for research into the impacts of key threats (and how to manage them) will help ensure our unique flora are not lost forever.

Prof Hugh Possingham and Dr Ayesha Tulloch discuss the 2020 findings of the Threatened Plant Index.

CORRECTION: A previous version of this article incorrectly stated that reviews of federal environment laws and the threatened species strategy found a lack of data, recovery actions and conservation funding for plants. While those problems were identified in public submissions to the reviews, the reviews themselves are not yet finalised.The Conversation

Ayesha Tulloch, DECRA Research Fellow, University of Sydney; Elisa Bayraktarov, Postdoctoral Research Fellow in Conservation Biology, The University of Queensland; Hugh Possingham, Professor, The University of Queensland; Jaana Dielenberg, University Fellow, Charles Darwin University; Jennifer Silcock, Post-doctoral research fellow, The University of Queensland; Micha Victoria Jackson, Postdoctoral research fellow, The University of Queensland, and Nathalie Butt, Postdoctoral Fellow, The University of Queensland

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

‘Severely threatened and deteriorating’: global authority on nature lists the Great Barrier Reef as critical



Shutterstock

Jon C. Day, James Cook University and Scott F. Heron, James Cook University

The Great Barrier Reef is now in “critical” condition and the health of four other Australian World Heritage properties has worsened, according to a sobering report just released by the International Union for Conservation of Nature (IUCN).

The IUCN is the global authority on nature. Its third outlook report marks the first time the IUCN has declared an Australian property as critical, which means its values are severely threatened and deteriorating. The health of the Blue Mountains, Gondwana Rainforests, Shark Bay and the Ningaloo Coast has also been downgraded.




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The assessment, while chastening, is not surprising. The Great Barrier Reef has endured three mass coral bleaching events in five years, and last summer’s bushfires caused untold damage in the Blue Mountains and Gondwana Rainforests (not to mention the current fires at the reef’s Fraser Island).

Climate change remains the key issue for World Heritage places, not just in Australia but globally. In fact, the IUCN assessment found climate change threatens 11 of Australia’s 16 properties. This raises further questions over our national climate response.

World Heritage: the best of the best

The latest report builds on previous reports from 2014 and 2017, and shows the status and trends of World Heritage properties identified for their outstanding natural values. As the report states:

our ability to conserve these sites is thus a litmus test for the broader success of conservation worldwide.

To qualify for World Heritage listing for natural values, a place must meet one or more of four criteria: exceptional beauty, geology, ecological processes, and species and habitats.

Some properties are also recognised for cultural values and, if they have both, they’re referred to as “mixed”. Across the world there are 252 natural and mixed World Heritage properties, of which 16 are in Australia.

The IUCN is the official advisor on nature to UNESCO’s World Heritage Committee. The IUCN Outlook report involves assessments by hundreds of international experts, who examine the conservation prospects of all natural and mixed World Heritage properties. It focuses on their natural values, the threats to these values and the effectiveness of actions to protect them.

Threats to our iconic places

Climate change is now the most prevalent threat to natural World Heritage sites, and to many cultural sites.

Overall, the report assessed climate change as a high or a very high threat in 83 out of 252 global properties (33%). This rate is double in Australia, with climate change listed as a threat to 69% (11 of 16) of Australian properties.

And when considering the four natural criteria individually, climate change is the greatest threat to each. This is likely to get worse in future, as climate change is expected to affect more than three times the number of properties impacted by any other threat.

For many properties, the deteriorated conservation outlook is the result of accumulated threats. Impacts of climate change, like coral bleaching and bushfires, are often exacerbated by other threats. For example, the federal government’s 2019 Outlook Report for the Great Barrier Reef listed 45 threats including climate change. This included poor water quality from land-based runoff, coastal development and fishing.

Aerial view of seagrass meadows and headlands in Shark Bay
Seagrass meadows and headlands in the World Heritage-listed Shark Bay Conservation Area, now rated as ‘good with some concerns’.
Shutterstock

At the time of writing, the website which provides the full rationale behind the IUCN outlook was not yet publicly available. However the threats facing the five downgraded Australian sites are well documented.

These include marine heatwaves, which lead to coral bleaching in the Great Barrier Reef and Ningaloo. In Shark Bay, marine heatwaves also cause seagrass — critical habitat for a vast diversity of species — to die-off. Poor water quality, such as from urban and agricultural run-off, is another big threat to the Great Barrier Reef.




Read more:
‘Bright white skeletons’: some Western Australian reefs have the lowest coral cover on record


More frequent and intense bushfires are a problem for the Blue Mountains, Shark Bay, and Gondwana Rainforests. These ancient rainforests, along with Ningaloo and Shark Bay, also face threats of invasive species, diseases and storms.

Punching below our weight

While there have been some successes globally, the threats facing our heritage places are escalating.

Since the 2017 assessment, of the 252 properties analysed globally, 16 (6%) have deteriorated and only eight (3%) showed improvement. Notably, Australia is punching below its weight, with 31% of properties having deteriorated (5 of 16) and zero with improvement.




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Prepare for hotter days, says the State of the Climate 2020 report for Australia


All of Australia’s World Heritage properties are recognised as having “highly effective” or “mostly effective” protection and management activities.

But the deterioration of the Great Barrier Reef, the Blue Mountains, Gondwana Rainforests, Shark Bay and Ningaloo Coast casts doubt on whether these actions are an effective response to threats, especially climate change.

A whale shark
Western Australia’s Ningaloo Coast, now downgraded to ‘good with some concerns’, is famous for its vast diversity of wildlife, including whale sharks.
Shutterstock

Australia’s climate response has been widely criticised, most recently by Christiana Figueres, the former chief of the UN Climate Framework. In a keynote to open the Australian Emissions Reductions Summit yesterday, Figueres said:

I have been pretty vocal about my frustration for so many years of the completely unstable, volatile, unpredictable stand and position on climate change in Australia.

“Meeting and beating” Australia’s 2030 emissions targets has been the Morrison government’s catch-cry. But the target lacks ambition and the government hasn’t ruled out using Kyoto carry-over credits to help meet it. The government has also refused to commit to a target of net-zero emissions by mid century, in contrast to the policies of many of our international peers.

Management of non-climate stressors is, and will remain, essential to halt the decline of the values of our properties. But Australia must adopt more ambitious climate goals to avoid losing those values that make our heritage places special, preserving them for future generations.




Read more:
NSW has joined China, South Korea and Japan as climate leaders. Now it’s time for the rest of Australia to follow


The Conversation


Jon C. Day, PSM, Post-career PhD candidate, ARC Centre of Excellence for Coral Reef Studies, James Cook University and Scott F. Heron, Associate professor, James Cook University

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