AUSTRALIA

Expert says to brace for bushfire season ahead, but expect worse to come

by Ben Knight, University of New South Wales

Credit: Pixabay/CC0 Public Domain

The upcoming bushfire season in Australia may be bad, but future years pose a more significant threat, says a University of New South Wales bushfire expert.

The recent devastation caused by wildfires across Europe and Hawaii has sparked concerns about the return of catastrophic bushfires in Australia. Coupled with the forecast that the southern hemisphere is likely entering a hot and dry El Niño event, conditions could be favorable for major fires after a few years of subdued activity.

But Professor Jason Sharples, an expert in bushfires dynamics from UNSW Canberra, says while it's always hard to predict exactly what will unfold in Australia, it's unlikely to be a repeat of the 2019–2020 Black Summer bushfires.

"El Niño conditions don't necessarily mean we will have a worse bushfire season, though it does mean we're more likely to have hotter temperatures, less rainfall, and dry conditions that can lead to destructive fires," Prof. Sharples says. "Instead of being hit hard this year, we may see the impacts of El Niño accumulate and combine with climate change in the next season and the ones following."

However, Prof. Sharples says this season may still bring a chance of significant fires developing. Three years of increased rainfall from consecutive La Niña events has seen vegetation grow, especially grasses, and a relatively dry year so far may have begun to dry it out.

"In many areas, there is still some moisture content in forest fuels like trees, leaves and branches, as well the litter on the ground, but it takes a while, probably more than one season, to dry out," Prof. Sharples says. "So, while the vegetation has grown a lot, and there may be a lot of fuel lying around, it's probably not ready to burn with that intensity this year.

"However, there are still some forested areas that have already seen significant drying, and these areas could see intense bushfires."

The Black Summer bushfires also burned a lot of forest areas along south-east Australia already. While reburn fires could occur this year, Prof. Sharples says they're unlikely to be as severe, though other untouched forest areas along the coast could still burn.

Instead, grassland areas, which have also grown over the last few years of rainfall, may be more at risk this season.

"There is a higher possibility of grass fires this year, in areas like western New South Wales, though they're not typically as damaging as large forest fires," Prof. Sharples says.

"The biggest area burnt in Australia was due to a series of grassland fires that burnt 100 million hectares following a strong La Niña, so they can still be a significant hazard, particularly in rural areas."

Future bushfire season threats

While this upcoming season might not hit as hard as others in recent memory, Prof. Sharples says the risk of more severe and frequent bushfires continues to grow from human-driven climate change.

"The fact that our worst bushfire season on record didn't coincide with an El Niño suggests climate change is acting, and we should prepare for worsening bushfire conditions in the years ahead," Prof. Sharples says.

Overall, bushfire seasons are getting longer and starting earlier. Heat waves, in particular, are becoming hotter, longer, and more frequent, drying out fuels and intensifying bushfires.

"The risk of extreme bushfires is rising because of climate change, and there is a clear link between hotter temperatures and worsening bushfires," Prof. Sharples says. "They're becoming more destructive and regular, and present a unique set of hazards as they interact with the atmosphere to create violent firestorms."

Prof. Sharples says we must act now to improve fire preparedness and management strategies to mitigate the increasing threat of bushfires.

"We're not going to be able to prevent bad seasons from occurring, but we can take steps to improve fire management techniques to prevent extreme fires as much as possible," Prof. Sharples says.

"If not, we will be locked in a vicious cycle of climate change leading to larger fires and then those larger fires amplifying the effects of climate change."

Prof. Sharples also says we need more research to understand the dynamics of fires and a lot of investment and interest in different technologies to help mitigate the risk of bushfires.

"It's not the sort of problem that gets solved in a single season," Prof. Sharples says. "It will take years, possibly even decades, of research and planning to better prepare ourselves for the kinds of bushfires we had in the Black Summer season."

Provided by University of New South Wales Bigger, wilder, more destructive: How cold fronts affected the Black Summer bushfires

Quokkas demonstrate adaptive behavior in response to prescribed burns

by Murdoch University

Credit: Pixabay/CC0 Public Domain

Quokkas residing in the Northern Jarrah Forest, Western Australia have been found to be using fire exclusion zones to ensure their own safety and longevity.

A study conducted by researchers at Murdoch University's Harry Butler Institute, working with the Department of Biodiversity, Conservation and Attractions, has shed light on their adaptive behavior following periods of prescribed burns. The study is published in the International Journal of Wildland Fire.

The findings emphasize the importance of appropriately sized and located fire exclusion areas in conservation management.

Harry Butler Institute researcher Leticia Povh led the study and said understanding how animals use their space after prescribed burning is crucial for effective conservation management, particularly for threatened species like the quokka.

"The study aimed to determine how individual quokkas changed their home ranges following burns," Povh said.

"In a world of rising temperatures and decreasing rainfall across southwest WA, this study has important conservation significance in determining how we manage habitat for our mainland quokkas into the future."

Over the course of two years, the movement patterns of 20 quokkas were meticulously tracked before and after prescribed burns.

Home-range area calculations were performed for each individual, and behavioral change point analysis was conducted to detect any alterations in their space use.

"The key results revealed a remarkable shift in the behavior of six quokkas that had previously resided in areas subjected to prescribed burns," Povh said.

"These individuals moved into fire exclusion zones, actively avoiding the burn areas for an average of three months.

"After this time, these quokkas spent no more than 2% of their time in the burn areas. In contrast, quokkas inhabiting fire exclusion and control sites did not exhibit any changes in their space use.

"This study highlights the importance of appropriately sized fire exclusion zones to ensure the preservation of populations of species dependent on dense vegetation."

Quokkas, like many other fauna species, rely on dense cover for refuge from introduced predators such as the feral cat and red fox, making fire exclusion areas a crucial component of prescribed burn planning.

By providing refuge and food sources, these areas contribute to the long-term viability of quokka populations and other species with similar habitat requirements.

As prescribed burns continue to be used in land management, the findings of this study offer useful insights for conservation practitioners.

By incorporating appropriately sized and located fire exclusion areas into prescribed burn planning, land managers can assist in preserving critical habitat for vulnerable wildlife like the quokka.

More information: Leticia F. Povh et al, A conservation-significant threatened mammal uses fire exclusions and shifts ranges in the presence of prescribed burning, International Journal of Wildland Fire (2023). DOI: 10.1071/WF22196

Provided by Murdoch University 

Tracking quokkas through fires

 

Hard yacca: Grass-trees are a life saver for many animals, but fire and disease threaten their survival

by University of South Australia

Grass-tree Xanthorrhoea semiplana ssp. semiplana. 

Credit: Pacific Conservation Biology (2023). DOI: 10.1071/PC23014

Australia's iconic grass-trees—aka yaccas—are hardy, drought-tolerant, and strikingly beautiful. Now, new research has revealed another, far more important, feature: their ability to protect wildlife from deadly weather extremes.

A study undertaken by the University of South Australia and Kangaroo Island Research Station shows that the yaccas' long, thick and dry grassy skirts help insulate animals from lethal temperatures in summer and winter, as well as keeping them dry. The research is published in Pacific Conservation Biology.

Temperatures under the grass-tree canopies at four sites in the Mt Lofty Ranges were up to 20 degrees cooler than under the direct sun in summer. In winter, conditions were significantly warmer under the grass skirts at night.

It turns out the iconic plant species—Xanthorrhoea semiplana sub species semiplana—also doubles as an effective umbrella, keeping the soil completely dry under 80% of the bigger, older yaccas during weeks of heavy rain.

Lead researcher Dr. Topa Petit says it's not surprising that many creatures seek shelter under yaccas, particularly the older species with the largest and thickest skirts.

"Several of the 29 species of Australian grass-trees are known to host native bush rats, threatened bandicoots, echidnas and pygmy-possums, among other wildlife," Dr. Petit says.

"Temperatures over 40 degrees can be lethal to some of our wildlife, but grass-trees provide extremely stable temperatures with very little variation.

"The remarkable ability of these grass-trees to protect wildlife from deadly climatic extremes—as well as providing effective hiding spots from predators—strengthens the mounting evidence that these plants are keystone species."

However, the yaccas on the mainland and Kangaroo Island are facing multiple threats which could have dramatic consequences for wildlife, Dr. Petit says.

The soil pathogen Phytophthora cinnamomi is having a devastating impact on the grass-trees, causing widespread dieback. Fuel reduction programs, summer fires and land clearing are threatening their survival even further.

"Grass-tree resilience to bushfires appears to be overestimated," Dr. Petit says.

"Moreover, even if grass-trees are not killed by fires, their very old thick skirts of dead leaves burn, leaving no shelter to animals in post-bushfire environments."

In 2022, the Federal Government added fire regimes that cause declines in biodiversity to the list of Key Threatening Processes.

"Historically, grass-trees were cleared for agriculture. They are now cleared or burnt in so-called fuel reduction programs. Extensive research has shown that this practice increases fuel loads and dries out the landscape."

Dr. Petit says yaccas scorched by fire can take decades to regain their role as effective shelters and are more susceptible to Phytophthora infestations.

"It's important that habitat management be backed by sound research and scientific monitoring rather than hysteria. We owe it to the future of our ecosystems."

More information: Sophie Petit et al, The role of grass-tree Xanthorrhoea semiplana (Asphodelaceae) canopies in temperature regulation and waterproofing for ground-dwelling wildlife, Pacific Conservation Biology (2023). DOI: 10.1071/PC23014

Provided by University of South Australia Kangaroo Island ants 'play dead' to avoid predators

 

Identifying fire victims through DNA analysis: A geneticist explains what forensics is learning from archaeology

by Anne Stone, The Conversation

Credit: CC0 Public Domain

Fire devastates communities and families, and it makes identification of victims challenging. In the aftermath of the wildfire that swept through Lahaina, Hawaii, officials are collecting DNA samples from relatives of missing persons in the hope that this can aid in identifying those who died in the fire.

But how well does DNA hold up under such extreme conditions, and what is the best way to recover DNA from fire victims?

I am an anthropological geneticist who studies degraded DNA in archaeological and forensic contexts. My research group applies ancient DNA and forensic analysis methods to optimize DNA recovery from burned bones. Retrieving DNA from severely burned remains in order to identify victims is a particular challenge.

Forensic DNA analysis

In a typical forensic investigation, DNA is extracted from a sample—whether some blood, pieces of tissue or bone—collected from the scene of the disaster or crime. This process chemically separates the DNA from other components of cells within the sample, such as proteins, and purifies it.

This DNA is used as a template for polymerase chain reaction, or PCR, analysis, a method that is essentially the Xerox copier of molecular biology. Even if there are only a few cells present in the sample, PCR can amplify those DNA molecules into thousands or millions of copies. This creates a sufficient amount of DNA for subsequent tests.

In forensics, the specific DNA targeted in PCR is usually a set of highly repetitive markers called microsatellites, or short tandem repeats. Law enforcement agencies around the world use specific sets of these markers for identification purposes. In the U.S., forensic analysts target 20 of these DNA repeats. Each person has two unique alleles, or genetic variants, at each of these markers, and these alleles are uploaded to the FBI's Combined DNA Index System database to identify matches.

DNA taken from the relatives of missing people will likely be analyzed for short tandem repeat markers and their allele profiles uploaded to the Relatives of Missing Persons index within the database. The expectation is that victims and their biological relatives share a percentage of alleles for these markers. For example, parents and children share 50% of their alleles, since a child inherits half of their DNA from each parent.

Challenge of degraded DNA

In forensic contexts, the time between death and DNA sampling is usually short enough that the DNA is often still in fairly good shape, both in terms of quantity and quality. However, DNA is often not found in ideal conditions after a disaster.

Time and the elements take their toll. After death, the process of decomposition releases enzymes that can cleave or damage DNA, and additional damage occurs over time depending on the environment in which the body is found. DNA also degrades faster in warm, wet, acidic environments and slower in colder, drier environments that are more pH neutral or slightly basic.

In addition, DNA preservation may vary considerably among the tissues, bones and teeth recovered. For example, researchers found that DNA identification of victims of the World Trade Center attacks in 2001 was most successful when using bones of the feet and legs, compared with bones from the head and torso.

DNA analysis can help identify victims by comparing genetic similarities between people.

DNA damage can take different forms. Nicks and breaks in the DNA make it difficult to analyze. Chemical modification of the DNA can result in changes to the original sequence or make it unreadable. This includes changes to the building blocks of DNA called nucleotides that make up an identifiable sequence. For example, exposure to water can cause a chemical reaction called deamination that changes the nucleotide cytosine such that it appears to be the nucleotide thymine upon analysis. Exposures to other chemicals or UV light can cause cross-linking, which essentially ties the DNA into knots. As a result, the PCR enzymes used to copy or read the DNA sequence can't move linearly along the DNA strand.

Applying methods from archaeology

Researchers encounter similar issues in handling degraded genetic material when analyzing the DNA of ancient remains that are thousands of years old. To address these challenges, forensic geneticists and ancient DNA researchers like me employ a number of tricks to optimize DNA retrieval.

First, we tend to target dense bone or teeth for sampling, since they are more impervious to the environment. We also use DNA extraction methods that enhance the recovery of short fragments of DNA.

Second, we use PCR to amplify even shorter genetic markers, including mini-short tandem repeats, or sections of the mitochondrial genome. Mitochondria are structures within each cell that produce energy, and each one has its own DNA. Mitochondrial DNA is passed down from mother to child and can be found in hundreds of copies within each mitochondrion, which make it easier to recover and analyze. However, mitochondrial DNA may not provide sufficient information for identification, since people who are maternally related, even very distantly, will share the same sequence.

Researchers are also testing newer methods of DNA analysis common in the ancient DNA field for forensic purposes. For example, special enzymes can remove chemically modified nucleotides, such as deaminated cytosines, to prevent misreading of the DNA sequence. Researchers can also use DNA baits to "fish" for specific sequences. This method of targeted enrichment can recover very small fragments that can be used to piece together the full genetic sequence.

DNA analysis of burned remains

For fire victims, particularly those caught in intense, extended fires, the DNA may be highly fragmented, making analysis difficult. High temperatures cause bonds between molecules, including nucleotides, to break. This results in fragmentation and ultimately destruction of the DNA.

Because hard tissue—bones and teeth—are often all that remains after a fire, forensic researchers have studied how bone characteristics such as color and composition change with temperature. My research team used this information to classify the level of burning that human bone samples have been subjected to.

In investigating DNA preservation in those samples, we found that there is a significant point of DNA degradation when bones reached temperatures between 662° Fahrenheit (350° Celsius) and 1,022°F (550°C). For comparison, commercial cremation is 1,400°F to 1,600°F (760°C to 871°C) for 30 to 120 minutes, and vehicle fires typically reach 1,652°F (900°C) but can last a shorter period of time.

Our team also found that the likelihood of generating high-quality short tandem repeat data or mitochondrial DNA sequence data, whether using forensic or ancient DNA methods, decreases significantly at temperatures greater than 1,022°F (550°C).

In sum, as temperature and exposure time increase, the amount of remaining DNA decreases. This leads to only partial DNA profiles, which can limit analysts' ability to match a victim to a relative with high statistical certainty or prevent results altogether.

DNA evidence is not the only method used for identification. Investigators combine DNA with other evidence—such as dental, skeletal and contextual information—to identify a victim conclusively. Together, this information hopefully will help bring closure for families and friends.

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

The Idaho student homicides and forensic genetics

AUGUST 21, 2023

Yellowknife fires: Evacuees will need culturally specific support services

by Jack L. Rozdilsky, The Conversation

Credit: Pixabay/CC0 Public Domain

On the evening of Aug. 16, due to rapidly moving wildfires, an evacuation order was issued for the entire city of Yellowknife. Thousands of residents faced a long, stressful drive on the only road out of the city. The goal was for as many people as possible to flee one of the largest cities in Canada's North before the deadline for safe exit of Aug. 18 at noon Mountain Daylight Time.

As a researcher in disaster and emergency management, I have studied the implications of what happened in Fort McMurray, Alta., in 2016, a similar situation where a large city in Canada's North faced full evacuation due to fire. I am also a member of a research team at York University that looks at "emergency management for all"—analyzing how the needs of the whole community are met, or not, during mass emergencies.

We studied Fort McMurray's Muslim community to explore how they experienced mass evacuation. Our research found that the needs of a segment of the population were overlooked during mass evacuation. Perhaps, seven years later, this will not happen again.

Similarities to Fort McMurray

In May 2016, a large fast-moving wildfire jumped from the surrounding rural areas and into the city of Fort McMurray, Alta., causing approximately 88,000 people to flee. Canadians were shocked and saddened by the televised images of slow-moving lines of cars passing in close proximity to massive walls of flames.

In August 2023, Canadians are again seeing disturbing images of slow-moving traffic along smoky two-lane roads in Canada's remote northern locales. While it is too soon to make detailed comparisons between the Fort McMurray evacuation in 2016 and the ongoing Yellowknife evacuation, there appear to be some things in common.

At both places, evacuations are made more difficult due to northern Canada's geographic realities. Highway evacuations involve traversing hundreds of kilometers, and airlifts face capacity limits, although an official said there is room for everyone who wants to fly out.

During Fort McMurray's evacuation, only one southbound road was available for evacuation. Similar to northern Alberta, the Northwest Territories has limited infrastructure, and most people evacuating Yellowknife can only use one road to drive to reception centers hundreds of kilometers south in Alberta.

Reuters reports on the evacuation order issued in Yellowknife, N.W.T.

Culturally appropriate services

While it is hoped that fire conditions change, it is possible that the fire will reach the outskirts of Yellowknife. If that happens, it could be weeks if not months before 20,000 residents can return. Other locales will have to absorb Yellowknife's entire population for extended periods.

In the immediate short term, the needs of the evacuees will shift from temporary relief to requiring more permanent services. Evacuees will benefit if some semblance of "home away from home" can be provided. That hospitality includes culturally appropriate evacuee hosting.

At the time of the 2016 fire disaster at Fort McMurray, the largest visible minority group was the Muslim community. Today, there are still 7,000 to 10,000 Muslims residing in Fort McMurray.

Whether it was fully understood during the chaos of the 2016 fire evacuations or not, thousands of people had specific cultural needs that became evident in evacuation centers.

As days turned to weeks, challenges for Muslim evacuees emerged. The disaster occurred during the start of Ramadan, and scheduled mass feeding times in large shelters conflicted with traditional sunrise-to-sunset fasting during Ramadan. Evacuation centers hosting Fort McMurray's evacuees were unprepared for meeting the needs of the sizeable Muslim population.

Anticipating diverse needs

Like Fort McMurray, Yellowknife is a culturally diverse community. When Yellowknife's diverse population arrives at reception centers in Alberta, it is an open question whether they will be met with culturally appropriate services. Initial analysis indicates at least three significant distinct cultural groups among the evacuees from Yellowknife.

Canada's Northwest Territories is home to Indigenous Peoples, and Yellowknife is located on the traditional lands of the Dene First Nation. Friendship centers in Alberta, such as in Grande Prairie and High Level, are offering support, food and other necessities to Indigenous evacuees from the Northwest Territories.

The largest visible minority group in Yellowknife is the Filipino population, with about 1,065 people.

Historically, Yellowknife has attracted a significant number of French-speaking people, and there is a significant francophone community, making up nearly 17 percent of the city's population.

There is no 'one size fits all'

As the mass evacuation of Yellowknife unfolds, the needs of minority, racialized and marginalized populations will emerge. Past experiences indicate emergency officials at centers hosting evacuees in Alberta may not be ready to meet the needs of a diverse population.

Again, there exists the potential for minority populations having their needs overlooked by emergency services during mass evacuations. We know from the Fort McMurray experience that social issues related to diversity, equity and inclusion are real-life concerns impacting the evacuation experiences for thousands of Canadians.

The unfolding Yellowknife evacuation effort will not be a one-size-fits-all experience for Northwest Territorians. At this early point in the mass evacuation, it can be anticipated that social and cultural needs of all Yellowknifers will need to be acknowledged and acted upon.

Adaptations to standard operating procedures will need to be made at evacuation centers in Alberta to meet the needs of thousands of people with varying and culturally specific needs arriving from Yellowknife.

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

Military airlifts provide escape as wildfires sweep Canada's far north

AUGUST 21, 2023

Milder weather brings relief from 'apocalyptic' Canada wildfires

by Paula RAMON, with Michel COMTE in Ottawa

The McDougall Creek wildfire burns in the hills of West Kelowna. Evacuation orders were put in place in the area of Kelowna, with a population of 150,000, as the fire threatened the city.

Cooling weather on Monday gave firefighters a slight edge against what the prime minister described as "apocalyptic" wildfires blazing across western Canada, after tens of thousands were evacuated or put on alert.

Two fires threatening large parts of the scenic Okanagan Valley, including the cities of Kelowna and neighboring West Kelowna in British Columbia, merged over the weekend.

Around 30,000 people in the province where 385 fires are now burning—out of almost 1,040 nationwide—had been under evacuation orders while another 36,000 were under alert to be ready to flee.

British Columbia's emergency management minister, Bowinn Ma, warned that the situation was "highly dynamic."

West Kelowna Fire Chief Jason Brolund, however, sounded a note of optimism, telling a news conference late Sunday: "We're finally feeling like we're moving forward, rather than we're moving backwards."

Temperatures in the major wine-producing region around Kelowna were expected to stay cool through Monday, creeping into the low 20 degrees Celsius (68 Fahrenheit) in the afternoon.

There was also some rain forecast starting Tuesday.

Officials said it was too soon to start planning a staged return of evacuees as thick smoke continued to choke the area.

Prime Minister Justin Trudeau at a cabinet retreat in Charlottetown, Prince Edward Island, to discuss the national fire crisis said Canadians "are watching in horror the images of apocalyptic devastation."

Boats sit amongst smoke from the nearby Bush Creek East Wildfire on Shuswap Lake in Gleneden, British Columbia. Two fast-moving "extreme" wildfires merged overnight in western Canada, threatening hundreds more homes and forcing continued evacuations in a wide swath of British Columbia province.

"It's a scary and heartbreaking time," he said as "people flee for their lives and worry about their communities."

This summer in Canada, more than 14 million hectares (34.6 million acres) has already burned—roughly the size of Greece and almost twice the area of the last record of 7.3 million hectares. Four people have died so far.

Scientists say human-caused global warming is exacerbating natural hazards, making them both more frequent and more deadly.

'Horrible to breathe'

Kelowna, a city of 150,000, has become the latest population center hit.

"It has been horrible to spend the week with this air. It is horrible to breathe," Mary Hicks, a 29-year-old IT worker who had been visiting the region from Montreal, told AFP on Sunday. "I really want to go home."

But she was stuck for now, with her return flight canceled. The airport hopes to resume flights this week, depending on visibility.

"When I had to pack, in the moment I was crying, crying, crying," said April, 39, who with her two small children fled her home east of Kelowna and was staying in a hotel outside the city.

On the other side of Okanagan Lake, a number of homes on the outskirts of West Kelowna had been burned.

Charred remains are seen on the side of the road on the highway in Enterprise. The tiny hamlet, a key junction on the road south from Yellowknife in the Northwest Territories, has been almost completely destroyed by fires.

"My sister's boyfriend's house has burnt down. He lives in the West Kelowna side and it was so windy that the fire was spreading and they couldn't control it," said Bogi Bagosi, a 16-year-old student.

"It's kind of heartbreaking to watch the city burn down. They are doing their best to stop it but it is not enough."

The confusion and terror of the fires and evacuations have been compounded by Meta's blocking of Canadian news on Facebook and Instagram, in response to a new law requiring digital giants to pay publishers for articles.

"It is inconceivable that a company like Facebook is choosing to put corporate profits ahead of (safety)... and keeping Canadians informed about things like wildfires," Trudeau said Monday.

Cooler with rain 'a bit of help'

In Canada's far north, crews held back a massive fire threatening Yellowknife, the capital of the Northwest Territories. They were helped by some rain over the weekend.

Yellowknife—now a ghost town, except for emergency personnel who stayed behind to build fire barriers and lay out sprinklers—and many small communities in the near-Arctic region have been evacuated, leaving two thirds of the population of the Northwest Territories displaced.

"With a little bit of help from the weather over the past few days and a lot of good firefighting work we've been able to keep this thing at bay for the time being," local fire information officer Mike Westwick told a briefing.

© 2023 AFP

Canada wildfires spread and merge as evacuations continue

Yellowknife and Kelowna wildfires burn in what is already Canada's worst season on record

by Andrew Weaver, The Conversation

Credit: Pixabay/CC0 Public Domain

The devastating wildfire that destroyed the historic Maui town of Lahaina in Hawaii was still making headlines when the Northwest Territories issued an evacuation order for Yellowknife and British Columbia declared a provincewide state of emergency.

All 22,000 residents of Yellowknife are being evacuated in advance of a wall of flame from out-of-control wildfires converging on the capital city. Yet this isn't the first time an entire Canadian town has been cleared.

In May 2016, all 90,000 residents of Fort McMurray, Alta., were evacuated shortly before wildfires engulfed 2,400 homes and businesses with a total cost of more than $4 billion.

In 2017 in British Columbia, the wildfire season led to the evacuation of more than 65,000 residents across numerous communities, costing $130 million in insured damages and $568 million in firefighting costs.

Let's not forget the June 2021 heat dome resulting in temperature records being broken across British Columbia three days in a row. The heat wave culminated in Lytton, a village in the southern part of the province, recording 49.6°C on June 29, the hottest temperature ever observed anywhere in Canada and breaking the previous record by five degrees. The next day, wildfires engulfed Lytton, destroying more than 90% of the town.

Long, hot summer

The summer of 2023 is one for the record books. June and July were the warmest months ever recorded, and extreme temperature records were broken around the world.

By mid-July, Canada had already recorded the worst forest fire season on record. And British Columbia broke its previous 2018 record for worst recorded forest fire season. With several weeks to go in the 2023 forest fire season, more than six times the 10-year average area has already been consumed by wildfires.

And yet, this pales in comparison to what we can expect in the years ahead from ongoing global warming arising from greenhouse gas emissions released through the combustion of fossil fuels.

Predicted outcomes

This year's fire season record will be broken in the near future as warming continues. And once again, it's not as if what's happening is a surprise.

Almost 20 years ago, my colleagues and I showed that there already was a detectable human influence on the observed increasing area burned from Canadian wildfires. We wrote:

"The area burned by forest fires in Canada has increased over the past four decades, at the same time as summer season temperatures have warmed. Here we use output from a coupled climate model to demonstrate that human emissions of greenhouse gases and sulfate aerosol have made a detectable contribution to this warming. We further show that human-induced climate change has had a detectable influence on the area burned by forest fire in Canada over recent decades."

It appears little has been done to prepare rural Canada for what's in store as governments deal with immediate, rather than transformational approaches to wildfire management.

This, despite the existence of the national FireSmart program designed to assist homeowners, neighborhoods and communities decrease their vulnerability to wildfires and increase their resilience to their negative impacts.

Forest management practices including forest fire prevention, monoculture reforestation and the use of glyphosate to actively kill off broadleaf plant species, will all have to be reassessed from a science- and risk-based perspective.

Growing number of court cases

Pressure is certainly mounting on decision-makers to become more proactive in both mitigating and preparing for the impacts of climate change.

An Aug. 14 pivotal ruling from the Montana First Judicial District Court sided with a group of youth who claimed that the State of Montana violated their right to a healthy environment.

A similar case brought by seven youth against the Ontario government after the province reduced its greenhouse gas reduction targets has also been heralded as groundbreaking.

As the number of such court cases grow, governments and corporations will need to do more to both protect their citizens from the impacts of climate change, and to aggressively decarbonize energy systems.

I wouldn't be surprised if the Alberta government is next to be taken to court by youth after Premier Danielle Smith's outrageous economic and environmental decision to put a moratorium on renewable energy projects.

States of emergency

While attention is currently turned to the evacuation of Yellowknife, it's sobering to remind ourselves that they are not alone. The village of Lytton, burnt to the ground just two years ago, has been put on evacuation alert as wildfires approach.

Kelowna has just declared a state of emergency as the McDougall Creek fire starts consuming homes in the region. And this, coming on the heels of the 20th anniversary of the Okanagan Mountain Park fire, when more than 27,000 people had to be evacuated and 239 Kelowna homes were lost.

Canadians will take solace as summer turns into winter and the immediacy of our 2023 wildfire situation wanes. Unfortunately, it will be Australia's turn next to experience the burning wrath of nature in response to human-caused global warming and the 2023 El Niño.

Rather than waiting to respond reactively to the next fire season, proactive preparation is the appropriate way forward. For as the old adage states: an ounce of prevention is worth a pound of cure.

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

Military joins wildfire fight in Canada's far north

HERE KITTY, KITTY

Did sabertooth tigers purr or roar? The answer may lie in a tiny string of bones

by Tracey Peake, North Carolina State University

Schematic of felid hyoid anatomy in situ in (a) Panthera tigris and (b) Caracal caracal. 

Stylohyoid is orange, epihyoid (* = ligamentous in Panthera) is purple, ceratohyoid is 

yellow, basihyoid is red, and thyrohyoid is cyan. 

Credit: Journal of Morphology (2023). DOI:10.1002/jmor.21627

When a sabertooth tiger called out, what noise did it make—a mighty roar or a throaty purr? A new study from North Carolina State University researchers has examined the data behind the arguments for each vocalization and found that the answer was more nuanced than they thought—and that it could depend on the shape of a few small bones. The work appears in the Journal of Morphology.

Modern cats belong to one of two groups: either the pantherine "big cats," including the roaring lions, tigers and jaguars; or Felinae "little cats," which include purring cats like lynxes, cougars, ocelots and domestic cats.

"Evolutionarily speaking, sabertooths split off the cat family tree before these other modern groups did," says Adam Hartstone-Rose, professor of biological sciences at NC State and corresponding author of the research. "This means that lions are more closely related to housecats than either are to sabertooths.

"That's important because the debate over the kind of vocalization a sabertooth tiger would have made relies upon analyzing the anatomy of a handful of tiny bones located in the throat," Hartstone-Rose continues. "And the size, shape and number of those bones differ between modern roaring and purring cats."

Although vocalization is driven by the larynx and soft tissue in the throat, not bones, anatomists noticed that the bones responsible for anchoring those tissues in place—the hyoid bones—differed in size and number between roaring and purring cats.

"While humans have only one hyoid bone, purring cats have nine bones linked together in a chain and roaring cats have seven," says Ashley Deutsch, a Ph.D. student at NC State and lead author of the research. "The missing bones are located toward the top of the hyoid structure near where it connects to the skull."

"Because sabertooth tigers only have seven bones in their hyoid structure, the argument has been that of course they roared," Hartstone-Rose says. "But when we looked at the anatomy of modern cats, we realized that there isn't really hard evidence to support this idea, since the bones themselves aren't responsible for the vocalization. That relationship between the number of bones and the sound produced hasn't ever really been proven."

Credit: North Carolina State University

The researchers looked at the hyoid structures of four species of roaring cats: lions, tigers, leopards and jaguars; and five species of purring cats: cougars, cheetahs, caracals, servals and ocelots. They compared these to 105 hyoid bones from the iconic sabertooth tiger Smilodon fatalis.

"You can argue that since the sabertooths only have seven bones, they roared, but that's not the whole story," Hartstone-Rose says. "The anatomy is weird. They're missing extra bones that purring cats have, but the shape and size of the hyoid bones are distinct. Some of them are shaped more like those of purring cats, but much bigger."

According to the researchers, if the missing bones (called epihyoid bones) were key to different vocalizations, the bones most closely connected to them should look different between the two groups. However, those bones looked very similar in shape whether they came from purring or roaring cats.

In fact, the researchers saw more shape variation in the bones closer to the vocal apparatus; i.e., the thyrohyoid and basihyoid bones. The uniformity of the upper bones between the two groups suggests that if the hyoid structure plays a role in vocalization, the lower bones are more important than the upper ones. So having these key hyoid bones shaped like those of purring cats could indicate that they purred rather than roared.

"We found that despite what history has told us about the number of bones in the hyoid structure, no one has validated the significance of that difference," Hartstone-Rose says. "If vocalization is about the number of bones in the hyoid structure, then sabertooths roared. If it's about shape, they might have purred. Due to the fact that the sabertooths have things in common with both groups, there could even be a completely different vocalization."

"It is perhaps most likely that the size of the hyoids plays a role in the pitch of vocalization," says Deutsch. "Although Smilodon wasn't quite as big as the largest modern cats, its hyoid bones are substantially larger than those of any of their living relatives, so potentially they had even deeper vocalizations than the largest tigers and lions."

Brian Langerhans, associate professor of biology at NC State, and former NC State undergraduate Deanna Flores also contributed to the work.

More information: Ashley R. Deutsch et al, The roar of Rancho La Brea? Comparative anatomy of modern and fossil felid hyoid bones Journal of Morphology (2023). DOI: 10.1002/jmor.21627. onlinelibrary.wiley.com/doi/10.1002/jmor.21627

Journal information: Journal of Morphology 

Provided by North Carolina State University Why you shouldn't declaw tigers or other big cats