It’s bee season. To avoid getting stung, just stay calm and don’t swat



Shutterstock

Caitlyn Forster, University of Sydney and Tanya Latty, University of Sydney

This summer’s wetter conditions have created great conditions for flowering plants. Flowers provide sweet nectar and protein-rich pollen, attracting many insects, including bees.

Commercial honey bees are also thriving: the New South Wales population has reportedly bounced back after the drought and bushfires

While you may have seen a lot of bees around lately, there’s no reason to be afraid. Most bees are only aggressive when provoked, and some don’t sting at all. And some bee-like insects are actually flies.

We are experts on honey bee and other insect behaviour. So let’s look at which bees to watch out for, and how to avoid being stung this summer.

Blue banded bee
Most bees, like this native blue banded bee, are not very interested in people.
Shutterstock

Is it a bee, or a wanna-bee?

Bees in Australia comprise both introduced and native species.

Invasive bees found in Australia, all of which can sting, include the widespread European honeybees, bumble bees in Tasmania, and Asian honey bees in Queensland.




Read more:
The mystery of the blue flower: nature’s rare colour owes its existence to bee vision


Australia is also home to about 2,000 native bees, including 11 stingless species.

Stingless bees live in colonies and produce honey. Other native species, such as blue banded bees and leaf cutter bees, are capable of stinging but are rarely aggressive.

Some insects we see around flowers are actually harmless hoverflies. But their yellow and black stripes mean they are often mistaken for bees.

A hoverfly
Hoverflies have similar colouring to honeybees.
Caitlyn Forster

Bees out and about

Bees on flowers are usually more interested in the food they’re collecting than the people around them. However, if you’re concerned about encountering one on your morning walk or in the garden, there are simple ways to mitigate the risk.

Bees sting when they feel threatened. So when you see one, move slowly and keep your distance. If bees fly close to you, avoid sudden movements such as swatting them away.

And wear closed shoes where bees might fly close to the ground, such as around clover or fallen jacaranda flowers.

Bee approaching wattle flower
If you see a bee in the garden, avoid sudden movements.
Shutterstock

What if I see a swarm?

In spring and into summer, healthy honeybee colonies may reproduce by dividing into two. One part of the colony stays at the hive and the other goes looking for a new home.

Worker bees and the queen bee leave the hive in a swarm and find a spot to stay temporarily while scout bees find a new home. That’s when you might see a swarm on a tree, vehicle or building.

Once scout bees find a new home, they return to the swarm and communicate the location via the “waggle dance”. Once a sufficient number of scouts agree on a new nest site, the swarm lifts into the air and flies to its new home.




Read more:
Curious Kids: how do bees make honey?


Don’t panic if you encounter a stationary swarm of bees. The bees will sting only if threatened. But keep your distance.

Moving swarms can pose a higher sting risk, and should be avoided. If you encounter one, move a safe distance away, or indoors if possible. When moving away, avoid fast movements or swatting.

Swarms are usually present for a few hours or days before they move to a permanent location. If the bees are in a risky location (for example, near a footpath or other busy areas), call a beekeeper to safely remove them.

Stingless native bees swarm for two reasons: mating and fighting.

Mating swarms involve males congregating outside a hive to mate with the queen. Fighting swarms occur when a colony of stingless bees attempts to invade another colony. They do not usually pose a risk to humans.

Native bees capable of stinging are solitary, so don’t swarm. However, male solitary bees are known to group together on branches in the evening.

Bee swarm on a fence during a 2018 cricket match
Bee swarms, such as this on a fence during a 2018 cricket match, usually move on in a few days.
Brendon Thorne

When a bee sting happens

Death and serious injury from bee stings is rare. But in Australia, bees are responsible for more hospital visits than snakes or spiders. European honeybees are also responsible for more allergic reactions than any other insect.

Only female bees can sting. Honeybees can only sting once, and die shortly after. This is because their stinger is barbed – once it stings something, the bee can’t pull the stinger out. Instead the stinger pulls free from the bee’s abdomen and the bee dies.

Other species can sting multiple times because their stingers are not barbed.

When a bee’s stinger enters your skin, it injects venom from a sac on its abdomen. When this happens, you’re likely to experience temporary swelling and redness.

For most people, reactions to bee venom are shortlived. To limit the amount of venom injected by the bee, quickly remove the sting using the edge of your fingernail or credit card.

In some cases, stings can lead to severe allergic reactions, including anaphylaxis. If you think you may have an allergy to bee stings, speak to your doctor.

And seek medical advice if you are stung in the face or neck, if significant swelling occurs or if you develop symptoms such as wheezing, light-headedness or dizziness.

Person squeezing bee sting on arm
Many people develop swelling and redness after a bee sting.
Shutterstock

Learning to like bees

Bees and other insects play an important role in our food production, by moving pollen from one plant to another. They do a similar job in your garden, helping flowers and fruits to flourish.

But worldwide, bees and other pollinators face many threats, including climate change, misuse of pesticides and habitat loss. We must do what we can to keep pollinator populations healthy.

So if you’re out and about and see a bee, or even a swarm, try not to panic. The bees are probably focused on the job at hand, and not interested in you at all.




Read more:
‘Jewel of nature’: scientists fight to save a glittering green bee after the summer fires


The Conversation


Caitlyn Forster, PhD Candidate, School of Life and Environmental Sciences, University of Sydney and Tanya Latty, Associate professor, University of Sydney

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.




Read more:
Drones, detection dogs, poo spotting: what’s the best way to conduct Australia’s Great Koala Count?


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.

The mystery of the blue flower: nature’s rare colour owes its existence to bee vision



Shutterstock

Adrian Dyer, RMIT University

At a dinner party, or in the schoolyard, the question of favourite colour frequently results in an answer of “blue”. Why is it that humans are so fond of blue? And why does it seem to be so rare in the world of plants and animals?

We studied these questions and concluded blue pigment is rare at least in part because it’s often difficult for plants to produce. They may only have evolved to do so when it brings them a real benefit: specifically, attracting bees or other pollinating insects.

We also discovered that the scarcity of blue flowers is partly due to the limits of our own eyes. From a bee’s perspective, attractive bluish flowers are much more common.

A history of fascination

The gold and blue funerary mask of the ancient Egyptian pharaoh Tutankhamun.
The ancient mask of the pharaoh Tutankhamun is decorated with lapis lazuli and turquoise.
Roland Unger / Wikimedia, CC BY-SA

The ancient Egyptians were fascinated with blue flowers such as the blue lotus, and went to great trouble to decorate objects in blue. They used an entrancing synthetic pigment (now known as Egyptian blue) to colour vases and jewellery, and semi-precious blue gemstones such as lapis lazuli and turquoise to decorate important artefacts including the Mask of Tutankhamun.




Read more:
Feeling blue? Get acquainted with the history of a colour


Blue dye for fabric is now common, but its roots lie in ancient Peru, where an indigoid dye was used to colour cotton fabric about 6000 years ago. Indigo blue dyes reached Europe from India in the 16th century, and the dyes and the plants that produced them became important commodities. Their influence on human fashion and culture are still felt today, perhaps most obviously in blue jeans and shirts.

Renaissance painters in Europe used ground lapis lazuli to produce dazzling works that captivated audiences.

A painting of a woman in a vivid blue robe and white hood, with bowed head and clasped hands.
The Virgin in Prayer by the Italian painter Sassoferrato, circa 1650, highlights the vivid blue colour made with ground lapis lazuli.

Today many blues are created with modern synthetic pigments or optical effects. The famous blue/gold dress photograph that went viral in 2015 not only shows that blue can still fascinate — it also highlights that colour is just as much a product of our perception as it is of certain wavelengths of light.

Why do humans like blue so much?

Colour preferences in humans are often influenced by important environmental factors in our lives. An ecological explanation for humans’ common preference for blue is that it is the colour of clear sky and bodies of clean water, which are signs of good conditions. Besides the sky and water, blue is relatively rare in nature.

What about blue flowers?

We used a new online plant database to survey the the relative frequencies of blue flowers compared to other colours.

Among flowers which are pollinated without the intervention of bees or other insects (known as abiotic pollination), none were blue.

But when we looked at flowers that need to attract bees and other insects to move their pollen around, we started to see some blue.

This shows blue flowers evolved for enabling efficient pollination. Even then, blue flowers remain relatively rare, which suggests it is difficult for plants to produce such colours and may be a valuable marker of plant-pollinator fitness in an environment.

Global flower colour frequency for human visual perception (A) shows when considering animal pollinated species less than 10% are blue (B), and for wind pollinated flowers almost none are observed to be blue (C).
Dyer et al., Author provided

We perceive colour due to how our eyes and brain work. Our visual system typically has three types of cone photoreceptors that each capture light of different wavelengths (red, green and blue) from the visible spectrum. Our brains then compare information from these receptors to create a perception of colour.

For the flowers pollinated by insects, especially bees, it is interesting to consider that they have different colour vision to humans.




Read more:
Inside the colourful world of animal vision


Bees have photoreceptors that are sensitive to ultraviolet, blue and green wavelengths, and they also show a preference for “bluish” colours. The reason why bees have a preference for bluish flowers remains an open field of research.

Various blue flowers from our study.

Why understanding blue flowers is important

About one-third of our food depends on insect pollination. However, world populations of bees and other insects are in decline, potentially due to climate change, habitat fragmentation, agricultural practices and other human-caused factors.

The capacity of flowering plants to produce blue colours is linked to land use intensity including human-induced factors like artificial fertilisation, grazing, and mowing that reduce the frequency of blue flowers. In contrast, more stressful environments appear to have relatively more blue floral colours to provide resilience.

For example, despite the apparent rarity of blue flower colours in nature, we observed that in harsh conditions such as in the mountains of the Himalaya, blue flowers were more common than expected. This shows that in tough environments plants may have to invest a lot to attract the few available and essential bee pollinators. Blue flowers thus appear to exist to best advertise to bee pollinators when competition for pollination services is high.

Knowing more about blue flowers helps protect bees

Urban environments are also important habitats for pollinating insects including bees. Having bee friendly gardens with flowers, including blue flowers that both we and bees really appreciate, is a convenient, pleasurable and potentially important contribution to enabling a sustainable future. Basically, plant and maintain a good variety of flowers, and the pollinating insects will come.




Read more:
Our ‘bee-eye camera’ helps us support bees, grow food and protect the environment


The Conversation


Adrian Dyer, Associate Professor, RMIT University

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

An unexpected consequence of climate change: heatwaves kill plant pests and save our favourite giant trees



Shutterstock

Gregory Moore, University of Melbourne

Australia is sweltering through another heatwave, and there will be more in the near future as climate change brings hotter, drier weather. In some parts of Australia, the number of days above 40℃ will double by 2090, and with it the tragedy of more heat-related deaths.

In the complex world of plant ecology, however, heatwaves aren’t always a bad thing. Rolling days of scorching temperatures can kill off plant pests, such as elm beetles and mistletoe, and even keep their numbers down for years.

This is what we saw after the 2009 heatwave that reached a record 46.4℃ in Melbourne and culminated in the catastrophic Black Saturday bushfires. Years later, the trees under threat from the pest species were thriving. Here are a few of our observations.

Saving red gums from mistletoe

In the days following Black Saturday, botanists, horticulturists and arborists noticed a curious heatwave side-effect: the foliage of native Australian mistletoes (Amyema miquelii and A. pendula species) growing on river red gums lost their green colour and turned grey.

The two species of mistletoe are important in the ecology of plant communities and to native bird and insect species. But infestation on older trees can lead to their deaths, particularly in drought years.

Australian mistletoe is not related to the northern hemisphere mistletoes of Christmas kissing fame. They are water and nutrient parasites on their host tree and can kill host tissues through excessive water loss.

A eucalyptus tree trunk covered in leaves on a dried brown grass
The native mistletoe, Amyema miquelii, strangles this eucalyptus coolabah in the Burke River floodplain.
John Robert McPherson/Wikimedia, CC BY-SA

Often mistletoes go largely unnoticed, only becoming obvious when they flower. This is because many have evolved foliage with a superficial resemblance to the host species, a phenomenon known as host mimicry or “crypsis”.

During the Black Saturday heatwave, many mistletoes growing on river red gums died. The gums not only survived, but when record rains came in 2010, they thrived. A decade on, the mistletoe numbers are gradually increasing, but they’re still not high enough to threaten the survival of older, significant red gums.




Read more:
The world endured 2 extra heatwave days per decade since 1950 – but the worst is yet to come


We want both mistletoes and red gums to persist. But often the old red gums are last survivors of larger populations that have been cleared — a seed source for future regeneration.

Under-appreciated elms

In many parts of Australia, the exotic English and Dutch elms are important parts of the landscapes of cities and regional towns. Elms provide great shade, are resilient and often low-maintenance. They also provide important environmental services, such as nesting sites for native mammals and birds.

Indeed, as Dutch elm disease decimates elm populations across North America and Europe, Australia can claim to have many of the largest elms and the grandest elm avenues and boulevards in the world, which we often under-appreciate.

A street lined by tall elms
Australia is home to some of the most beautiful elm avenues in the world.
denisbin/Flickr, CC BY-ND

But sadly, over the past 30 years the grazing of the elm leaf beetle, Xanthogaleruca luteola, has threatened the grandeur of our elms. These beetles can strip leaves to mere skeletons, and while the damage doesn’t usually kill the tree, it can make them look unsightly.

On Black Saturday, tens of thousands of elm leaf beetles fell from trees after prolonged exposure to high temperature. So many died, they formed what looked like a shadow under the tree canopies. Beetle numbers remained low for at least five years after that.




Read more:
Why there’s a lot more to love about jacarandas than just their purple flowers


Control programs, which often involve spraying chemical pesticides, were not required in that five year period. This was good for the environment as the chemicals can affect non-target sites and species. And we calculated that this saved well over A$2 million for Melbourne alone, money that could be better spent on parks and gardens (and of course, the elms looked splendid!).

Our iconic Moreton Bay figs

Then there are our magnificent, iconic Moreton Bay figs (Ficus macrophylla). Their large, glossy leaves, huge trunks, veils of aerial roots and massive canopies spread for more than 40 metres, and make them an Australian favourite.

Moreton Bay figs are prone to insect infestations of the psyllid, Mycopsylla fici, which can seriously defoliate trees under certain conditions. The fallen leaves can also stick to the shoes of pedestrians, causing a slipping hazard.

In Melbourne, psyllid numbers that were high before Black Saturday fell to undetectable levels in the following month.

Once again, a heatwave and hot windy weather had done an unexpected service. The incidence of psyllids has remained low for a decade or more now and, as with elm leaf beetles, control measures proved unnecessary and money was saved.

An enromous Moreton Bay fig trunk in a park
Moreton Bay figs are prone to insect infestations.
Shutterstock

Winners and losers

Many urban trees are renowned for their resilience to stress, both natural and human-caused. Climate change is proving a significant stress to be overcome, but we’ve observed how the stress can affect pests and disease species more than their hosts.

This gives the species growing in very tough urban conditions, where they lack space and are often deprived of water and good soils, a slight advantage, which may be the difference between living and dying under climate change.




Read more:
Tree ferns are older than dinosaurs. And that’s not even the most interesting thing about them


Climate change is bringing far more losses than gains. But, occasionally, there will be wins, and those managing pests in our urban forests must take advantage when they present.

If insect pest numbers fall we can direct resources to establishing more trees and ensuring our trees are healthier. The best way to avoid pests and diseases attacking trees is by providing the best possible growing conditions. That way we avoid problems before they arise rather than treating symptoms.

So as you swelter during this heatwave, remember it may not be all bad news for our urban and natural environments. Sometimes, positive outcomes arise when and where we least expect them.




Read more:
As heatwaves become more extreme, which jobs are riskiest?


The Conversation


Gregory Moore, Doctor of Botany, University of Melbourne

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

Burnt ancient nutshells reveal the story of climate change at Kakadu — now drier than ever before



S. Anna Florin., Author provided

S. Anna Florin, University of Wollongong; Andrew Fairbairn, The University of Queensland; Chris Clarkson, The University of Queensland; James Shulmeister, University of Canterbury; Nicholas R Patton, University of Canterbury, and Patrick Roberts, Max Planck Institute for the Science of Human History

Archaeological research provides a long-term perspective on how humans survived various environmental conditions over tens of thousands of years.

In a paper published today in Nature Ecology and Evolution, we’ve tracked rainfall in northern Australia’s Kakadu region over the past 65,000 years. We wanted to know how major changes in rainfall may have affected the region’s Aboriginal communities through time.

Our findings suggest the Kakadu region wasn’t as prone to dry spells as surrounding areas — and it likely functioned as a place of refuge for early Australians as they struggled through harsh and arid conditions.

Learning lessons from leftovers

To generate a rainfall record spanning 65,000 years, we used ancient food waste left behind by the First Australians living at Madjedbebe, a rock shelter on Mirarr country in the Kakadu region.

This site boasts the earliest known evidence of humans living in Australia. It also boasts plenty of Pandanus spiralis, a native plant commonly called “pandanus” or “screw pine”.

This plant, known as “anyakngarra” to the Mirarr people — the Traditional Owners of Madjedbebe — is very important to them.

Anyakngarra fruit grows on a tree.
Anyakngarra (Pandanus spiralis) fruit. The tree is native to northern Australia and ubiquitous around the Top End’s waterholes and floodplains.
Author provided

Its leaves are used for weaving, its trunk to create dye, its fruit flesh is used in a drink and its nuts (the seed kernels within the fruit) are consumed as a rich source of fat and protein.

Anyakngarra’s nuts were also eaten by the First Australians 65,000 years ago. Discarded nut shells have been preserved as burned fragments, disposed of in fireplaces over time.

These small remnants have proven hugely useful for our research team, which includes archaeologists, environmental scientists and Traditional Owners.




Read more:
65,000-year-old plant remains show the earliest Australians spent plenty of time cooking


In a nutshell

By analysing the isotopic composition in ancient anyakngarra nutshells, we could track rainfall at Madjedbebe. Specifically, we detected how much water (and therefore rainfall) was available to anyakngarra plants in the past.

This analysis is possible due to photosynthesis – the process by which plants convert carbon dioxide in the air into sugars. Anyakngarra plants absorb two isotopes of carbon from the atmosphere: ¹²C and ¹³C. Isotopes are different types of atoms within a chemical element that have the same number of protons but a different number of neutrons. Chemically, the isotopes of carbon are the same, but each has a different atomic “weight”.




Read more:
Explainer: what is an isotope?


When environmental conditions are favourable, an anyakngarra plant will preferentially absorb more ¹²C than ¹³C. But if a plant is stressed by its environment, such as when it’s waterlogged due to seasonal flooding, it begins to absorb more ¹³C.

The isotopic composition (the ratio of ¹²C to ¹³C) is recorded in the sugars used by the plant for new tissue growth, including for the seasonal growth of nuts.

A higher proportion of ¹³C in a nutshell indicates that the plant it came from was waterlogged during its growth season. From this, we can conclude it likely experienced higher levels of rainfall.

Anyakngarra fruit.
Pictured is the anyakngarra fruit, which has a fleshy section (now dried and fibrous) a hard nutshell and multiple white seeds (or nuts) inside.
Author provided

Like an oasis in a desert

Over the past 72,000 years, humans have lived through an ice age in which there were two particularly cold periods called “stadials”. During stadials, glaciers extended to cover parts of North America, northern Europe, northern Asia and Patagonia (in South America).

The height of the second stadial in this ice age was called the Last Glacial Maximum. While this occurred 22,000 to 18,000 years ago, intense cold and dry conditions in Australia started as early as 30,000 years ago.

During this time, water availability was the main challenge in arid northern Australia (rather than low temperatures). The country’s arid zone expanded dramatically and parts of central Australia may have been temporarily abandoned by Aboriginal people.

Yet the “palaeoclimatic” record we generated for Madjedbebe indicates that, although glacial stages did lead to less rainfall, the Kakadu region remained relatively well-watered during these periods.

Our records show that for as long as people have been around, rainfall at Madjedbebe is unlikely to have dropped below current levels. Thus, this area would have helped early Australians survive during long dry spells and may have also attracted others from surrounding areas.

A site at the Madjedbebe is rock shelter in the Northern Territory.
This is our research site, the Madjedbebe rock shelter in the Alligator Rivers region of the Northern Territory.
Dominic O’Brien/Gundjeihmi Aboriginal Corporation, Author provided

Changing with the seasons

Our findings are supported by other archaeological evidence from Madjedbebe. For instance, our research has revealed more stone tools were left at this site during the glacial periods. This implies more people gathered there at these times.

Also, because the Kakadu region was still drier during glacial periods as compared to inter-glacial periods, people had to travel further for food and other important resources.




Read more:
Buried tools and pigments tell a new history of humans in Australia for 65,000 years


This is supported by evidence of an increased number of tools being brought to the site from further away. This points to increased mobility and new social arrangements being made as people adjusted to life in a harsher environment.

The challenge moving forward

Notably, over the past 65,000 years the driest time in the Kakadu region was not during the Last Glacial Maximum. It is today.

Rather than being the result of less rainfall occurring, this is likely due to higher evaporation caused by warmer inter-glacial temperatures. Aboriginal communities currently living in the Kakadu region are experiencing unprecedented aridity.

These difficult conditions are exacerbated by the threat of invasive plants and animals and disruption to cultural practices of landscape management, such as vegetation burning.

While the people of Kakadu have spent thousands of years adapting to environmental change, the scale and intensity of today’s anthropogenic impacts on regional climates and local landscapes poses an altogether different challenge.The Conversation

S. Anna Florin, Research fellow, University of Wollongong; Andrew Fairbairn, Professor of Archaeology, The University of Queensland; Chris Clarkson, Professor in Archaeology, The University of Queensland; James Shulmeister, Professor, School of Earth and Environmental Sciences, University of Canterbury; Nicholas R Patton, Ph.D. Candidate, University of Canterbury, and Patrick Roberts, Research Group Leader, Max Planck Institute for the Science of Human History

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

Wetlands have saved Australia $27 billion in storm damage over the past five decades



Shutterstock

Obadiah Mulder, University of Southern California and Ida Kubiszewski, Crawford School of Public Policy, Australian National University

Australia is in the midst of tropical cyclone season. As we write, a cyclone is forming off Western Australia’s Pilbara coast, and earlier in the week Queenslanders were bracing for a cyclone in the state’s far north (which thankfully, didn’t hit).

Australia has always experienced cyclones. But here and around the world, climate change means the cyclone threat is growing – and so too is the potential damage bill. Disadvantaged populations are often most at risk.

Our recent research shows 54 cyclones struck Australia in the 50 years between 1967 and 2016, causing about A$3 billion in damage. We found the damages would have totalled approximately A$30 billion, if not for coastal wetlands.

Wetlands such as mangroves, swamps, lakes and lagoons bear the brunt of much storm damage to coast, helping protect us and our infrastructure. But over the past 300 years, 85% of the world’s wetland area has been destroyed. It’s clear we must urgently preserve the precious little wetland area we have left.

A wetland close to coastal development.
Wetland areas provide important protection from cyclones.
Shutterstock

A critical buffer

National disasters cost Australia as much as A$18 billion each year on average. About one-quarter of this is due to cyclone damage.

Wetlands can mitigate cyclone and hurricane damage, by absorbing storm surges and slowing winds. For example in August 2020, Hurricane Laura hit the United States’ midwest. Massive damage was predicted, including a 6.5-metre storm surge extending 65 kilometres inland.

However the surge was one metre at most – largely because the storm drove straight into a massive wetland that absorbed most of the predicted flood.

In Australia, wetlands are lost through intentional infilling or drainage for mosquito control, or to create land for infrastructure and agriculture. They’re also lost due to pollution and upstream changes to water flows.

Caley Valley Wetlands,  next to Adani's Abbot Point coal terminal.
Australia’s wetlands are at risk. Pictured is the Caley Valley Wetlands, next to Adani’s Abbot Point coal terminal. Adani was fined for releasing polluted water into the wetland.
Gary Farr/ACF

Putting a price on cyclone protection

Our research set out to determine the financial value of the storm protection provided by Australia’s wetlands.

We examined the 54 cyclones that struck Australia in the five decades to 2016. We gathered data including:

  • physical damage wrought in each storm swath (or storm path)
  • gross domestic product (GDP) in the storm’s path
  • maximum windspeed during each storm, which helps predict damage
  • total area of wetlands in each swath.

Using a powerful type of statistics called Bayesian analysis, we estimated the extent to which GDP, windspeed and wetland area affected total damage. This allowed us to estimate damage caused in the absence of wetlands.

We found for every hectare of wetland, about A$4,200 per year in cyclone damage was avoided. This means the A$3 billion in cyclone damage over the past 50 years would have totalled approximately A$30 billion, if not for coastal wetlands.




Read more:
Restoring a gem in the Murray-Darling Basin: the success story of the Winton Wetlands


Importantly, the percentage of damage averted falls rapidly as wetland area decreases. And the protection afforded by a single hectare of wetland increases drastically if there are fewer other wetlands in the path of the storm. This makes protecting remaining wetland even more critical.

If the average cyclone path in Australia were to contain around 30,000 hectares of wetlands, it would avert about 90% of potential storm damage. If the wetland area dropped to 3,000 hectares, only about 30% of damage would be averted.

Climate change is making cyclones worse. By 2050, Australia’s annual damage bill could be as high as A$39 billion, assuming current levels of wetlands are maintained.

Seawalls and other artificial structures can be built along the coast to protect from storms. However, research in China has found wetlands are more cost-effective and efficient than man-made structures at preventing cyclone damage.

Unlike man-made structures, wetlands maintain themselves. Their only “cost” is the opportunity cost of not being able to use the land for something else.

People inspect cyclone damage
Wetlands can help prevent cyclone damage, such as this wrought in Queensland during Cyclone Debbie in 2017.
Dan Peled/AAP

Keeping wetlands safe

According to recent analysis by the authors, which is currently under peer review, global wetlands provide US$447 billion (A$657 billion) worth of protection from storms each year.

Of course, wetlands provide benefits beyond storm protection. They store carbon, regulate our climate and control flooding. They also absorb waste including pollutants and carbon, provide animal habitat and places for human recreation.

Wetlands are an incredibly important resource. It’s critical we protect them from development and keep them healthy, so they can continue to provide vital services.




Read more:
Our new model shows Australia can expect 11 tropical cyclones this season


This story is part of a series The Conversation is running on the nexus between disaster, disadvantage and resilience. You can read the rest of the stories here.The Conversation

Obadiah Mulder, PhD Candidate in Computational Biology, University of Southern California and Ida Kubiszewski, Associate Professor, Crawford School of Public Policy, Australian National University

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

The open Australian beach is a myth: not everyone can access these spaces equally



Silas Baisch/Unsplash

Michelle O’Shea, Western Sydney University; Hazel Maxwell, University of Tasmania, and Megan Stronach, University of Technology Sydney

Last week, the McIver’s Ladies Baths in Sydney came under fire for their (since removed) policy stating “only transgender women who’ve undergone a gender reassignment surgery are allowed entry”. The policy was seemingly in defiance of New South Wales’ anti-discrimintation and sex discrimination acts.

Managed since 1922 by the Randwick and Coogee Ladies Amateur Swimming Club, the baths are a haven for women, and the last remaining women’s-only seawater pool in Australia.

Just over 100 public ocean pools sit on Australia’s rocky coast, most in New South Wales. Segregated baths gave women a place to experience the water, prohibited from most beach access until “continental” (or mixed gender) bathing was introduced in the early 20th century.

The council removed the wording on the website, and put out a statement saying they have “always supported the inclusion of transgender women at McIver’s Ladies Baths”. But this weekend, trans women and allies gathered at the baths, calling for a specifically inclusive policy to be drawn up.

Writing for Pedestrian, Alex Gallagher called the baths “a queer haven”. Of beaches, they wrote:

There’s likely no other place I feel such an undercurrent of anxiety that I’ll face scrutiny for not conforming to a sexist ideal of what a body “should” look like than the beach.

This is the latest in a long history of discrimination at Australia’s public beaches. Indeed, Australia’s beaches and ocean pools are a window into deep divisions.

Sites of contest

With Captain Cook’s arrival in 1770, coastal beaches were the first sites of early interactions and confrontations between the Aboriginal people and the colonisers.

Indigenous women, such as the Palawa women of Tasmania, once had an intimate relationship with water environments. Water was a playground as well as a source of nourishment and socialisation.




Read more:
Hidden women of history: Wauba Debar, an Indigenous swimmer from Tasmania who saved her captors


The colonial erasure of these histories and knowledge has contributed to a culture where Aboriginal swimmers who defied convention – by participating in formal competition or by serving as lifeguards — were swimming against a tide of discrimination.

Aboriginal people were commonly caricatured at surf carnivals in degrading, costumed representations. The development of organised competitive swimming associations in Sydney in the late 1800s saw segregated “Natives’ Races”: scarcely mentioned in the media, except to demonstrate perceived white superiority in the baths.

Student Action for Aborigines protest outside Moree Artesian Baths, 1965. Aboriginal people were banned from the pool, and the protest drew national attention.
Mitchell Library, State Library of New South Wales and Courtesy SEARCH Foundation, CC BY

As recently as the 1960s, it was routine for Aboriginal people to be banned from public swimming pools.

Owing to this discriminatory legacy, Aboriginal people — despite a history of a strong water culture — have historically rarely participated in organised swimming. But positive changes are beginning to emerge. In the past ten years, there has been a 47% reduction in drowning deaths in Aboriginal and Torres Strait Islander people, reflecting the development of programs specifically tailored for remote communities.




Read more:
From segregation to celebration: the public pool in Australian culture


Ocean freedoms and fears

The first year women competed in swimming at the Olympic games, 1912, Australians Sarah “Fanny” Durack and “Mina” Wylie won medals. The McIver’s Ladies Baths were an important venue for their preparations.

Two women in heavy bathing suits.
Fanny Durack (left) and Mina Wylie at the 1912 Olympics in Stockholm.
Wikimedia Commons

But even as beaches and pools became desegregated along gender lines, women weren’t admitted as full members of Surf Lifesaving Australia until 1980.

Muslim people, in particular those women who wear the hijab, have also long faced discrimination on Australian beaches. This was brought to the fore at the Cronulla riots of December 2005, when a crowd of 5,000 mostly white young men rioted on Cronulla beach in a “Leb and Wog bashing day”.

Programs such as Western Sydney’s Swim Sisters challenge Islamophobia at Australia’s beaches. A sisterhood of religiously diverse women, the program allows women a space to challenge themselves and support each other. And 40 years after white women could join Surf Lifesaving, highly skilled Muslim women lifesavers are furthering the tides of change.

Physical access

Australians living with a disability often face poor beach access and a lack of specialised facilities such as beach matting, access ramps and beach wheelchairs.

Without easy access to the beach, many with a disability lack confidence in swimming in the ocean, and there are few training opportunities for carers to develop the skills to assist.

A blue mat cuts across the white sandy beach. A woman smiles in a beach wheelchair.
Mats allowing wheelchair access, and accessibility chairs that can travel on the sand and into the water, improve accessibility to beach spaces.
AAP Image/Supplied by City of Gold Coast

Here, too, there are positive signs of change, with Accessible Beaches Australia aiming to open all patrolled beaches to people with disability.

Despite our history, the myth Australia’s beaches are egalitarian spaces persists. We remain a long way off inclusivity for all in our public blue spaces.

The story of the McIver’s Ladies Baths is only the latest in a long history of discrimination. We must ensure everyone can find an ocean pool or beach where they belong.The Conversation

Michelle O’Shea, Senior Lecturer, School of Business, Western Sydney University; Hazel Maxwell, Senior Lecturer, University of Tasmania, and Megan Stronach, Post Doctoral Research Fellow, University of Technology Sydney

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