02/12/2021

(AU The Conversation) More Than 200 Australian Birds Are Now Threatened With Extinction – And Climate Change Is The Biggest Danger

The Conversation | 

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Authors
  •  is Professor of Conservation and Sustainable Livelihoods, Charles Darwin University
  •  is a University Associate, University of Tasmania
Up to 216 Australian birds are now threatened – compared with 195 a decade ago – and climate change is now the main driver pushing threatened birds closer to extinction, landmark new research has found.

The Mukarrthippi grasswren is now Australia’s most threatened bird, down to as few as two or three pairs. But 23 Australian birds became less threatened over the past decade, showing conservation actions can work.

The findings are contained in a new action plan released today. Last released in 2011, the action plan examines the extinction risk facing the almost 1,300 birds in Australia and its territories. We edited the book, written by more than 300 ornithologists.

Without changes, many birds will continue to decline or be lost altogether. But when conservation action is well resourced and implemented, we can avoid these outcomes.

Without change, threatened birds such as the southern emu wren, pictured, will be lost. Barry Baker

The numbers tell the story

The 216 Australian birds now at risk of extinction comprise:
  • 23 critically endangered
  • 74 endangered
  • 87 vulnerable
  • 32 near-threatened.
This is up from 134 birds in 1990 and 195 a decade ago.

We assessed the risk of extinction according to the categories and criteria set by the International Union for Conservation of Nature in its Red List of threatened species.

As the below graph shows, the picture of bird decline in Australia is not pretty – especially when compared to the global trend.

Authors supplied

What went wrong?
Birds are easily harmed by changes in their ecosystems.
Dean Ingwersen/BIRDLIFE AUSTRALIA


Birds are easily harmed by changes in their ecosystems, including introduced species, habitat loss, disturbance to breeding sites and bushfires. Often, birds face danger on many fronts.

The southeastern glossy black cockatoo, for example, faces no less than 20 threats.

Introduced cats and foxes kill millions of birds each year and are considered a substantial extinction threat to 37 birds.

Land clearing and overgrazing are a serious cause of declines for 55 birds, including the swift parrot and diamond firetail. And there is now strong evidence climate change is driving declines in many bird species.

A good example is the Wet Tropics of far north Queensland.

Monitoring at 1,970 sites over 17 years has shown the local populations of most mid- and high-elevation species has declined exactly as climate models predicted.

Birds such as the fernwren and golden bowerbird are being eliminated from lower, cooler elevations as temperatures rise.

As a result, 17 upland rainforest birds are now listed as threatened – all due to climate change.

The Black Summer bushfires of 2019-20 – which were exacerbated by climate change – contributed to the listing of 27 birds as threatened.

We estimate that in just one day alone – January 6, 2020 – about half the population of all 16 bird species endemic or largely confined to Kangaroo Island were incinerated, including the tiny Kangaroo Island southern emu-wren.

Some 91 birds are threatened by droughts and heatwaves. They include what’s thought to be Australia’s rarest bird, the Mukarrthippi grasswren of central west New South Wales, where just two or three pairs survive.

Climate change is also pushing migratory shorebirds towards extinction. Of the 43 shorebirds that come to Australia after breeding in the Northern Hemisphere, 25 are now threatened.

Coastal development in East Asia is contributing to the decline, destroying and degrading mudflat habitat where the birds stop to rest and eat.

But rising seas as a result of climate change are also consuming mudflats on the birds’ migration route, and the climate in the birds’ Arctic breeding grounds is changing faster than anywhere in the world.

The Black Summer bushfires devastated some bird populations. James Ross/AAP

The good news

The research shows declines in extinction risk for 23 Australian bird species. The southern cassowary, for example, no longer meets the criteria for being threatened. Land clearing ceased after its rainforest habitat was placed on the World Heritage list in 1988 and the population is now stable.

Other birds represent conservation success stories. For example, the prospects for the Norfolk Island green parrot, Albert’s lyrebird and bulloo grey grasswren improved after efforts to reduce threats and protect crucial habitat in conservation reserves.

Intensive conservation efforts have also meant once-declining populations of several key species are now stabilising or increasing. They include the eastern hooded plover, Kangaroo Island glossy black-cockatoo and eastern bristlebird.

And on Macquarie Island, efforts to eradicate rabbits and rodents has led to a spectacular recovery in seabird numbers. The extinction risk of nine seabirds is now lower as a result.

There’s also been progress in reducing the bycatch of seabirds from fishing boats, although there is much work still to do.

The Albert’s lyrebird has been a conservation success. Barry Baker

Managing threats

The research also examined the impact of each threat to birds – from which we can measure progress in conservation action. For 136 species, we are alarmingly ignorant about how to reduce the threats – especially climate change.

Some 63% of important threats are being managed to a very limited extent or not at all. And management is high quality for just 10% of “high impact” threats.

For most threats, the major impediments to progress is technical – we don’t yet know what to do. But a lack of money also constrains progress on about half the threats.

What’s more, there’s no effective monitoring of 30% of the threatened birds, and high-quality monitoring for only 27%.

Nevertheless, much has been achieved since the last action plan in 2010. We hope the new plan, and the actions it recommends, will mean the next report in 2030 paints a more positive picture for Australian birds.

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(ScienceAlert) Mysterious Vanishing Of Advanced Chinese Civilization 4,000 Years Ago Finally Solved

ScienceAlert - Peter Dockrill

Detail from ancient Liangzhu jade carving. (Liangzhu Archeology Ruins Management Bureau)

About 5,300 years ago, an ancient civilization emerged in the east of China, building a brilliant city the likes of which had perhaps never been seen before in all of Asia – nor possibly even the whole world.

The surviving traces of the Liangzhu culture, which rose up along the banks of the Yangtze River Delta in China's east, are a testament to what this unique Neolithic society was capable of in the final stretches of the Stone Age.

The archaeological ruins of Liangzhu City demonstrate numerous signs of social, cultural, and technological advancements for the period, especially in agriculture and aquaculture.

Sophisticated architectural features, meanwhile – including clever hydraulic engineering that enabled canals, dams, and water reservoirs – led to allusions of Liangzhu being a Neolithic "Venice of the East".

None of these marvels would last, however.

Aerial view of palace area of Liangzhu. Hangzhou Liangzhu Archaeological Site Administrative District Management Committee

After a single innovative millennium, the Liangzhu culture mysteriously collapsed around 4,300 years ago, and the ancient city was abruptly abandoned. Exactly why has never been fully understood, although many have suggested some form of catastrophic flooding led to the sudden decline.

"A thin layer of clay was found on the preserved ruins, which points to a possible connection between the demise of the advanced civilization and floods of the Yangtze River or floods from the East China Sea," explains geologist Christoph Spötl from the University of Innsbruck in Austria.

"However, no clear conclusions on the cause were possible from the mud layer itself."

Now, we have a clearer picture of the deluge that drowned this astounding place.

In a new study, Spötl and an international team of researchers went far deeper than the ancient mud deposits, examining mineral formations (or speleothems) such as stalagmites from two underwater caves in the region, which preserve chemical signatures of climatic conditions long ago.

Stalagmites in Shennong Cave. (Haiwei Zhang)

Led by first author Haiwei Zhang from China's Xi'an Jiaotong University, their analysis of the stalagmite samples shows the collapse of Liangzhu City coincided with a period of extremely high precipitation that likely lasted for decades over 4,300 years ago, probably due to increased frequency of El Niño–Southern Oscillation conditions.

"This is amazingly precise in light of the temporal dimension," Spötl says.

"Massive monsoon rains probably led to such severe flooding of the Yangtze and its branches that even the sophisticated dams and canals could no longer withstand these masses of water, destroying Liangzhu City and forcing people to flee."

According to the researchers, previous instances of climate change in the Yangtze River Delta region may have also impacted other Neolithic cultures that inhabited the area before the Liangzhu society rose up in a period of dry and relatively stable environmental conditions.

But history and weather meant this prosperous city could not endure forever.

"Archeological studies show the presence of large-scale hydraulic complexes such as large earthen dams near the Liangzhu city, which were constructed between [5,300 and 4,700 years before present]," the researchers write in their study.

"This suggests that the Liangzhu society was effectively managing water resources by using hydraulic infrastructure for flood mitigation and/or irrigation to survive in a dry climate."

With time, however, that dry climate seems to have gotten progressively drier, culminating in a possible 'megadrought' around 4,400 years ago, at which point dam construction appears to have ceased, since existing dams would have been sufficient under the arid conditions.

And then the rains came, falling in two distinct burst periods between roughly 4,400–4,300 years ago.

"Our speleothem records, together with geochemical evidence of flood deposits above the Liangzhu culture layer, suggest that massive rainfall in the entire middle-lower reaches of the Yangtze River Valley might have induced fluvial flooding and/or overbank marine flooding transported by the Yangtze River plume and thus impeded human habitation and rice farming," the authors explain.

"Massive flooding and inundation due to poor drainage in the low-lying land may have forced the Liangzhu people to abandon their capital city and dwellings in the Taihu Plain, ultimately leading to the collapse of the entire Liangzhu civilization."

For hundreds of years afterward, humid conditions remained, during which time other ancient cultures temporarily rose up to succeed the Liangzhu – at least, until another megadrought likely led to the "final demise" of Neolithic human societies in the region.

At about the same time, Chinese society was about to begin a transformational new chapter, with the founding of the Xia dynasty in 2070 BCE, considered to be the first dynasty of China, led by Yu the Great.

"While many documents indicate that the leader Yu built the Xia Dynasty because he successfully managed river flooding, some studies suggest that Yu's control of the flooding can be ascribed to climate change," the researchers explain, noting that their own speleothem data also back up the idea.

"This observation provides new robust evidence that the rise of the Xia Dynasty occurred in the context of a major climate transition from wet to dry, in line with the Chinese historic records and previous studies."

The findings are reported in Science Advances.

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(AU Climate Council) Steamy And Stormy: Climate Change And Summer 2021-22

Climate Council


La Niña is set to shape Australia’s summer 2021-22 with above-average rainfall forecast for eastern parts of the continent; elevating flood risks. Most of Australia, except in parts of the southeast, should expect above average maximum summer temperatures.

This explainer distils the latest advice from the Bureau of Meteorology on what to expect this summer. It takes stock of extreme weather risks, takes a close look at the impact of La Niña – the dominant climate driver affecting our weather now – and puts it all in the context of our changing climate.

What is La Niña, and how is it shaping the 2021-22 summer in Australia?

The Bureau of Meteorology declared that a La Niña is underway on November 23, 2021. Australia’s weather is influenced by a number of “climate drivers”, including the El Niño Southern Oscillation, Indian Ocean Dipole, Southern Annular Mode and Madden-Julian Oscillation.

These are cyclical fluctuations in ocean surface temperatures and ocean-atmosphere interactions in the Pacific Ocean, Indian Ocean, Southern Ocean and the tropics respectively. They influence year-to-year variations in temperature, rainfall and other weather patterns.

La Niña is one phase of the El Niño Southern Oscillation. It occurs when equatorial trade winds become stronger; bringing cooler water up from deeper in the ocean. This results in a cooling of the surface of the central and eastern tropical Pacific Ocean.

The stronger trade winds also help warm surface water accumulate in the western Pacific and to the north of Australia. These warmer waters in the western Pacific mean more clouds develop as warm, moist air rises. This can result in heavy rainfall to the north of Australia.

Source: Bureau of Meteorology (2013).

Every La Niña event is different, as the effects of La Niña may be amplified or dampened by the other climate drivers. 

The current La Niña is expected to persist until late summer or early autumn 2022. However, there are reasons to expect that this La Niña will not be as disruptive as the exceptionally strong event of 2010-12, including the fact that the 2010-12 La Niña coincided with a negative phase of the Indian Ocean Dipole. This tends to amplify the effects of La Niña. Right now, the Indian Ocean Dipole is in a neutral phase. 

But the Southern Annular Mode (SAM) is forecast to remain at positive levels to the end of the year. La Niña conditions in the Pacific Ocean, and the positive SAM phase are influencing the above average rainfall outlooks. See BoM’s latest ‘Climate Driver Update’ for more information.

According to the Bureau of Meteorology’s December to February (summer) outlook , and consistent with typical La Niña conditions, rainfall between December to February is likely to be above average for eastern Australia, particularly eastern parts of Queensland. 

Source: Bureau of Meteorology (2021)

The odds are stacked (1.5 to 3 times more likely) in favour of some unusually high maximum temperatures for most of the country away from the southeast. Below average daytime temperatures are likely for eastern NSW.

Source : Bureau of Meteorology (2021)

What extreme weather risks are we looking at this summer?

The Bureau of Meteorology’s Summer Outlook 2021-22 shows it is likely to be wetter than average for eastern parts of the continent, with higher risk of heavy rainfall and widespread flooding for these areas.

When it comes to cyclones, during La Niña years there are typically more cyclones in the Australian region than during non-La Niña years. During the 2010-12 La Niña there were several notable cyclones, including Cyclone Yasi – one of the strongest and costliest in Australia’s history.

Every year in which there have been more than one severe landfalling tropical cyclone in Queensland was a La Niña year. The Bureau of Meteorology has predicted an average to slightly-above-average number of cyclones for the 2021-22 season.


What does this mean for bushfire risks?

Above-average rainfall may seem like good news when it comes to reducing bushfire risks. However, rain in spring and early summer means lots of grass growth. If these grasses dry out quickly in the warm weather, the risk of fast-running grass fires increases.

The Bureau of Meteorology has warned that over summer 2021-22 we need to be mindful about grass and crop fires, particularly across inland areas and in the southwest of the country where we have had high grass growth over winter and spring. 

All in all, 2021-22 is unlikely to see a repeat of the horrendous conditions we experienced in the lead up to and during the Black Summer, although we must not be complacent. Sadly, due to accelerating climate change, we have entered a new era of greater fire risk and must be even more vigilant than before.

Source: Bureau of Meteorology (2021)

How does it all relate to climate change?

While the La Niña event will influence our weather this summer, it is important to remember that these short-term cyclical drivers are now occurring in the context of a warming climate.

Australia’s temperature and rainfall variability are also influenced by global warming caused by human activities, primarily the burning of coal, oil and gas and land use changes like deforestation. All weather now occurs in an atmosphere that is warmer, wetter and more energetic.

Australia’s climate has warmed by around 1.44°C between 1910 and 2019. A warmer atmosphere can hold more water vapour – seven percent more for every degree of warming. A warmer and wetter atmosphere also provides more energy for weather systems that generate intense rainfall.

This means that while climate change may only result in a modest increase in the overall amount of rain globally – limited by the moisture holding capacity of the atmosphere – it’s leading to a dramatic increase in the heaviest and most damaging rainfall events. 

In recent decades, and especially across northern Australia, a greater proportion of our rain is coming in the form of short, intense downpours. This trend is set to continue, and increases the risk of dangerous floods.

Ignoring climate change is costly

 Australians are already paying the price for the carbon pollution that’s been added to the atmosphere over the past two centuries.

The cost of extreme weather disasters in Australia has more than doubled since the 1970s, reaching $35 billion for the decade 2010-2019.

Queensland bears the highest burden with the state’s total losses from extreme weather disasters since the 1970s around three times those of Victoria, and about 50% greater than NSW. On a per person basis, Queensland’s losses were more than twice the national average.

Source: Climate Council (2021) Based on data from EM-DAT, the International Disaster Database: https://www.emdat.be/

For more information, see the Climate Council report, ‘Hitting Home: The Compound Costs of Climate Inaction’.

Governments, like the Australian Government, that failed to reduce emissions over the past decade have sentenced Australians, and communities worldwide, to a far more dangerous future than if they had heeded repeated warnings from scientists.

Due to this past inaction, gradual, measured steps are no longer enough to avoid catastrophe. At this point, truly transformative action is required. That means at least halving global emissions over the coming decade and reaching net zero emissions globally by 2040 at the latest.

Australia, as a developed country with abundant potential for renewable energy, should aim to reduce its emissions by 75% by 2030 and reach net zero by 2035.

No developed country has more to lose from climate change-fuelled extreme weather, or more to gain as the world transforms to a zero-carbon economy, than Australia does. It is in all of our interests to do more to cut emissions, urgently and rapidly.

For more information, see ‘Aim High, Go Fast: Why Emissions Need to Plummet this Decade’ which is the Climate Council’s science-backed vision for what Australia’s best effort could look like.

Stay Safe this Summer

Stay safe everyone, and if you haven’t already done so, check your state/territory’s fire and emergency agency for advice on how to manage the summer’s extreme weather risks.

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