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Urban coyotes are literally full of garbage — and that's risky for humans, study suggests – CBC.ca

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On slicing open the stomachs of urban coyotes, researcher Scott Sugden has pulled out food scraps that might have come straight out of a garbage or compost bin, including a fully wrapped burrito. One time, he even found a leather glove.

“I can understand a pineapple. I can understand a burrito. I can understand a doughnut. But a leather glove?” said Sugden, a research assistant at the University of Alberta in Edmonton. “There’s no nutritional value whatsoever.”

From Vancouver to Montreal, coyotes are increasingly being spotted in urban parks and neighbourhoods. And their junk food diet spells bad news for both the animals and the people they live alongside. 

Coyotes that eat food discarded by humans tend to be unhealthy and may pose a health risk to humans since they carry more parasites and have gut bacteria linked to aggression, research by Sugden and University of Alberta colleagues found. Their study was published in the journal Scientific Reports last December. 

There is also a greater risk of contact and conflict with humans as their poor health pushes them to seek out more food meant for human consumption instead of hunting rodents like mice and voles.

“Hunting an animal is work and requires energy, and so it’s difficult for a coyote to do if it’s unhealthy,” Sugden said.

That makes the coyotes more reliant on human compost and garbage, which in turn makes them less healthy and perpetuates a vicious cycle, he said.

Some of the items found in the stomach of a single coyote in the University of Alberta study. Clockwise from the left: a leather glove, a Tim Hortons wrapper, small fruits including cherry pits and a grape stem scavenged from a yard or compost or garbage bin, an apple, a rodent’s paw and some grass. (Scott Sugden/University of Alberta)

Keeping coyotes away from garbage is crucial

Coyotes have been in the spotlight in recent months amid reports of attacks on people and pets, raising questions over how city dwellers and their pets can live safely alongside the animals.

At least 15 people have been bitten or attacked by coyotes in Vancouver’s Stanley Park in recent months, and conservation officers have warned that some have become aggressive and bold because they’ve been fed by humans.  

WATCH | Why coyotes are biting joggers in Stanley Park:

The Stanley Park Ecological Society explains the reasons behind the surge in recent attacks and what can be done to stop them. 3:38

Sugden’s research highlights the dangers of coyotes eating food meant for humans.

He examined nearly 100 urban and rural coyotes killed in the Edmonton area over the winters of 2017-2018 and 2018-2019 to see what they ate and how it affected their health. Coyotes don’t chew their food and instead tend to rip them and swallow whole, making it easy to identify what was eaten, he says.

The fact a coyote would swallow a glove was clearly a sign of desperation, says Sugden.

“He was hungry, and he wanted something to fill his stomach,” he said.

University of Alberta researcher Scott Sugden examines a coyote in a laboratory. He opened the stomachs of nearly 100 urban and rural coyotes to examine their diet and its impact on their health. (Scott Sugden/University of Alberta)

Sugden also looked beyond the contents of their stomachs — which only records their last meal or two — and looked at chemicals in the claws of the animals for insight on their diet.

The type of carbon and nitrogen found in the tissues is linked to diet. Higher levels of nitrogen-15 are linked to eating more protein, while higher levels of carbon-13 are often tied to consuming processed human foods containing corn-based ingredients such as high fructose corn syrup, cornstarch and maltodextrose.

Junk food diet linked to deadly parasites 

Sugden’s analysis suggested urban coyotes ate 2.5 times more human food than rural coyotes, and 25 per cent less prey — consistent with the finding that there were fewer mice, voles, and chunks of deer in the stomachs of urban coyotes compared to those of rural coyotes. 

There were also signs that the urban coyotes were in poorer health compared to their rural counterparts: 

  • They had much less fat in their kidneys, suggesting they weren’t as well nourished. 
  • They had 37 per cent larger spleens for their size, suggesting they had more challenges to their immune system.
  • They were 50 per cent more likely to carry the parasitic tapeworm E. multilocularis, which can cause a potentially deadly illness when transmitted to humans.

Dr. Emily Jenkins, professor and acting head of the Department of Veterinary Microbiology at the University of Saskatchewan in Saskatoon, has been researching the parasite for quite some time but was not involved in Sugden’s study.

“The irony is it actually has almost zero impact on coyotes’ health, but it has significant impacts for human health and for dogs,” she said.

E. multilocularis is a parasitic tapeworm found in coyotes. It’s harmless to coyotes, but in rare cases can cause a potentially deadly illness when the eggs are ingested by humans or dogs. ( Jenkins Lab/Zoonotic Parasite Research Unit/Western College of Veterinary Medicine)

If a dog or human accidentally eats the tapeworm eggs found in the feces of an infected coyote — something that’s relatively rare — the larvae form cysts in the liver.

“It basically behaves like a parasitic tumour and can spread and even be fatal without immediate and aggressive treatment,” she said.

Jenkins says while the parasite is rare, there has been an increase in reported cases in western Canada and southern Ontario — and the risk is enough to keep her from allowing her own dog off leash in either her own city of Saskatoon or in Edmonton, where she grew up.

The parasite tends to affect younger animals, and the younger age of the urban coyotes in the study might help explain why they had more parasites, she said.

On the other hand, she said the larger spleen suggested the urban coyotes might have more infections with other pathogens that the researchers didn’t look for.

Gut link to aggression?

For Sugden, the most interesting bit was the impact an unnatural diet had on the microbes that live in the gut of the coyotes.

In humans, those microbes, known as the gut microbiome, have been found to have an impact on health, behaviour and the immune system, and the same is true for animals, Sugden said.

He found that coyotes that ate more human food had more gut bacteria similar to those in humans than those that hunted more prey.

“For coyotes, this was bad news because this was correlated with other aspects of poor health,” he said.

There’s also some evidence it could be linked to more aggression by the animals.

Fusobacteria in the gut are linked to protein-rich diets and lower aggression in dogs, Sugden said. And one urban coyote in the study that killed a large domestic dog had no Fusobacteria in its gut at all.

“If we feel that eating human food has the potential to affect behaviour, [then we need] to address the root,” he said. “Then we reduce the likelihood of conflict. We reduce the likelihood of parasite transmission.”

Jenkins cautions against reading too much into links between different facets of the study since none were shown to cause each other. For example, the aggressive coyote mentioned in the paper may have been infected with a disease unrelated to its microbiome, she said.

However, she agreed that keeping coyotes away from human food is key to reducing risks to humans.

WATCH | Ottawa boy, 13, capturing urban coyotes on camera:

Last spring, 13-year-old Aidan Brown put up a handwritten sign to warn Linton Park visitors about the presence of coyotes. Now, with two new trail cams and an Instagram account, he’s raising even more awareness. 0:33

Are you feeding coyotes inadvertently?

Many cities, such as Calgary, Toronto and Vancouver, already ban residents from feeding wildlife and threaten violators with fines. Edmonton is considering such a bylaw.

Securing compost and garbage bins to prevent inadvertent feeding is also important, says Sugden.

The wildlife conservation group Coyote Watch Canada also recommends that people:

  • Keep pet food and water bowls indoors
  • Pick ripe fruit and remove rotten fruit from the ground
  • Avoid having large amounts of bird seed on lawns as they can attract prey such as birds and rodents.

Sugden said excluding coyotes from cities isn’t practical, but the animals can be encouraged to remain in natural urban areas such as river valleys and hunt their regular prey. 

Jenkins agreed that making human neighbourhoods less appealing for coyotes and controlling access to garbage is the most effective long-term solution. She said culling coyotes tends not to work, as the habitat “will refill almost immediately with new, needy, desperate young coyotes with exactly the same risk factors” such as tapeworm infections.

“We’ve got lots to learn about the wildlife and what that means for our health as well,” she said. 

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World strives to limit damage as greenhouse gas levels hit record

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Greenhouse gas concentrations hit a record last year and the world is “way off track” on capping rising temperatures, the United Nations said on Monday, showing the task facing climate talks in Glasgow aimed at averting dangerous levels of warming.

A report by the U.N. World Meteorological Organization (WMO) showed carbon dioxide levels surged to 413.2 parts per million in 2020, rising more than the average rate over the last decade despite a temporary dip in emissions during COVID-19 lockdowns.

WMO Secretary-General Petteri Taalas said the current rate of increase in heat-trapping gases would result in temperature rises “far in excess” of the 2015 Paris Agreement target of 1.5 degrees Celsius above the pre-industrial average this century.

“We are way off track,” he said. “We need to revisit our industrial, energy and transport systems and whole way of life,” he added, calling for a “dramatic increase” in commitments at the COP26 conference beginning on Sunday.

The Scottish city of Glasgow was putting on the final touches before hosting the climate talks, which may be the world’s last best chance to cap global warming at the 1.5-2 degrees Celsius upper limit set out in the Paris Agreement.

“It is going to be very, very tough this summit,” British Prime Minister Boris Johnson said during a news conference with children.

“I am very worried because it might go wrong and we might not get the agreements that we need and it is touch and go, it is very, very difficult, but I think it can be done,” he said.

The German government announced Chancellor Angela Merkel will travel to Glasgow to take part.

STAKES ARE HUGE

The stakes for the planet are huge – among them the impact on economic livelihoods the world over and the future stability of the global financial system.

Saudi Arabia’s crown prince said on Saturday that the world’s top oil exporter aims to reach “net zero” emissions of greenhouse gases, mostly produced by burning fossil fuels, by 2060 – 10 years later than the United States. He also said it would double the emissions cuts it plans to achieve by 2030.

An official plan unveiled in Ottawa showed developed nations were confident they can reach their goal of handing over $100 billion a year to poorer countries to tackle climate change by 2023, three years late.

The plan on how to reach the goal, prepared by Canada and Germany, said developed countries still needed to do more and complained private finance had not lived up to expectations.

A Reuters poll of economists found that hitting the Paris goal of net-zero carbon emissions will require investments in a green transition worth 2%-3% of world output each year until 2050, far less than the economic cost of inaction.

By contrast governments since January 2020 have spent a total of $10.8 trillion – or 10.2% of global output – in response to the COVID-19 pandemic.

‘WE DON’T HAVE TIME’

A “business-as-usual” trajectory leading to temperature rises of 1.6C, 2.4C and 4.4C by 2030, 2050 and 2100 respectively would result in 2.4% lost output by 2030, 10% by 2050 and 18% by 2100, according to the median replies to the survey.

Australia’s cabinet was expected to formally adopt a target for net zero emissions by 2050 when it meets on Monday to review a deal reached between parties in Prime Minister Scott Morrison’s coalition government, official sources told Reuters.

The ruling coalition has been divided over how to tackle climate change, with the government maintaining that harder targets would damage the A$2-trillion ($1.5-trillion) economy.

In London, climate activists restarted their campaign of blockading major roads by disrupting traffic in the city’s financial district, while in Madrid a few dozen people staged a sit-in protest, briefly blocking the Gran Via shopping street.

“Greenhouse gas emissions are provoking climate catastrophes all over the planet. We don’t have time. It’s already late and if we don’t join the action against what’s happening, we won’t have time to save what is still left,” said Alberto, 27, a sociologist who took part in the protest.

 

(Additional reporting by William James and Kylie MacLellan in London, Zuzanna Szymanska in Berlin, David Ljunggren in Ottawa and Marco Trujillo in Madrid; Writing by Michael Shields, Editing by William Maclean)

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New nuclear reactors can help France become carbon neutral by 2050 -RTE

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French grid operator RTE said next generation nuclear reactors offer an affordable path to shifting the country’s energy mix away from fossil fuels and make the aim of carbon neutrality by 2050 achievable.

“Building new nuclear reactors is economically viable, especially as it makes it possible to maintain a fleet of around 40 gigawatts (GW) in 2050,” said the RTE in a report examining the different pathways to meet the expected rise in electricity demand.

Industry and government sources say the report is expected to help inform President Emmanuel Macron’s decision to go ahead with plans to build new nuclear plants.

Le Figaro reported last week that Macron wants to announce the construction of six new EPR nuclear reactors by the end of the year.

Achieving future carbon neutral goals without nuclear reactors would require a scale up of renewables faster than the most dynamic electric mixes in Europe, RTE said.

France and several other European countries have pushed to label nuclear energy as green investments in the European Union’s upcoming sustainable finance rules.

The carbon neutral goals will be “impossible” without a significant development of renewable energy, RTE said.

Other supply options include the development of further interconnectors between countries, expanding hydraulic storage, and installing batteries to store renewable power.

New thermal power plants that utilise carbon-free gases, such as “green hydrogen” which is produced through the use of renewable energy, can also be used in order to meet rising consumption forecasts, the operator said.

RTE said the current energy crisis shows Europe’s dependence on hydro-carbons, such as gas and coal, has an economic cost and that low-carbon production in the country is an issue of energy independence.

France’s nuclear safety watchdog ASN in February cleared more than half of the nuclear fleet to operate for a decade longer than originally planned after maintenance work, as 32-900 megawatt reactors are coming to the end of their lifespan.

France currently has about 62.4 GW of nuclear generation capacity provided by 57 reactors, RTE data showed.

REACTION

Environmental groups decried the report’s emphasis on nuclear energy and supported calls for a quicker build out of renewable generation.

Greenpeace focused on the three pathways which would see the grid operated on 100% renewable energy and called for debates on the energy transition.

“This not only proves that nuclear power is not a necessary evil, but also that, whatever option is chosen, renewable energies need massive development to respond to the climate emergency,” Greenpeace said.

The RTE report said that scenarios with high shares of renewables, or those that extend reactor life beyond 60 years, would “involve heavy bets on technology” to meet carbon neutrality goals.

French Green party members described the report as one-sided and an attempt to justify new nuclear projects while disregarding consumption control measures.

“The goal of the president of the Republic and his government is clear: to justify the revival of nuclear power at any cost,” said Matthieu Orphelin, who used to represent Macron’s party but who has joined the Greens.

The French renewable energy union SER said the scenarios presented in the report represented “a major paradigm shift,” as it is expected that renewables will need to cover at least 50% of demand by 2050.

(Reporting by Forrest Crellin and Dominique Vidalon; Editing by Sudip Kar-Gupta and Mike Harrison)

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Explainer: Climate change: what are the economic stakes?

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COP26 climate talks in Glasgow starting next Sunday may be the world’s best last chance to cap global warming at the 1.5-2 degrees Celsius upper limit set out in the 2015 Paris Agreement.

The stakes for the planet are huge – among them the impact on economic livelihoods the world over and the future stability of the global financial system.

Here are 10 climate change-related questions that economic policy-makers are trying to answer:

1) HOW MUCH DOES CLIMATE CHANGE COST? From floods and fires to conflict and migration: economic models struggle with the many possible knock-on effects from global warming. The ballpark IMF estimate is that unchecked warming would shave 7% off world output by 2100. The Network for Greening the Financial System (NFGS) group of world central banks puts it even higher – 13%. In a Reuters poll of economists, the median figure for the output loss in that scenario was 18%.

2) WHERE IS THE IMPACT GOING TO BE FELT HARDEST? – Clearly, the developing world. Much of the world’s poor live in the tropical or low-lying regions already suffering climate change fall-out like droughts or rising sea levels. Moreover their countries rarely have the resources to mitigate such damage. The NFGS report projects overall output losses of above 15% for much of Asia and Africa, rising to 20% in the Sahel countries.

3) WHAT DOES THAT MEAN FOR INDIVIDUAL LIVELIHOODS? Climate change will drive up to 132 million more people into extreme poverty by 2030, a World Bank paper last year concluded. Factors included lost farming income; lower outdoor labour productivity; rising food prices; increased disease; and economic losses from extreme weather.

4) HOW MUCH WILL IT COST TO FIX IT? Advocates of early action say the sooner you start the better. The widely used NiGEM macroeconomic forecast model even suggests an early start would offer small net gains for output thanks to the big investments needed in green infrastructure. The same model warns of output losses of up to 3% in last-minute transition scenarios.

5) WHO LOSES OUT IN A “NET ZERO” CARBON WORLD? Primarily, anyone with fossil fuel exposure. A report by think tank Carbon Tracker in September estimated that over $1 trillion of business-as-usual investment by the oil and gas sector would no longer be viable in a genuinely low-carbon world. Moreover the IMF has called for the end of all fossil fuel subsidies – which it calculates at $5 trillion annually if defined to include undercharging for supply, environmental and health costs.

6) WHAT SHOULD CARBON REALLY COST? Tax or permit schemes that try to price in the damage done by emissions create incentives to go green. But so far only a fifth of global carbon emissions are covered by such programmes, pricing carbon on average at a mere $3 a tonne. That’s well below the $75/tonne the IMF says is needed to cap global warming at well below 2°C. The Reuters poll of economists recommended $100/tonne.

7) WOULDN’T THAT LEAD TO INFLATION? – Anything which factors in the polluting cost of fossil fuels is likely to lead to price rises in some sectors – aviation for example. That could in turn lead to what central banks define as inflation – broad-based and durable price rises across the whole economy. Yet history shows this hasn’t necessarily been the case: carbon taxes introduced in Canada and Europe pushed overall prices lower because they cut into household income and hence consumer demand, a recent study showed. It is also true that doing nothing could lead to inflation: a European Central Bank paper last year warned of food and commodity price rises from extreme weather events and the land shortages being caused by desertification and rising sea levels.

8) ARE GREEN ADVANCES REALLY DECOUPLING EMISSIONS FROM ECONOMIC GROWTH? Genuinely sustainable growth implies that economic activity can grow as needed without adding yet more emissions. This is the holy grail of “absolute decoupling”. But so far, any decoupling has either been largely relative – in the sense of merely achieving higher rates of economic growth than gains in emissions – or achieved by shifting dirty production from one national territory to another. And that is why, for now, global emissions are still rising.

9) WHO BEARS THE BRUNT OF TRANSITION? The idea of “Just Transition” has been espoused by bodies such as the European Union to acknowledge that the transition to net zero should happen in a fair way – for example by ensuring low-income groups are not made worse-off. At a global scale, the rich countries which since their industrial revolutions have generated the bulk of emissions have promised to help developing countries transition via $100 billion of annual transfers – a promise so far not fulfilled.

10) COULD THIS SPARK A FINANCIAL CRISIS? The global financial system needs to be insulated against both the physical risks of climate change itself and the upheavals likely to happen during a transition to net zero. Central banks and national treasuries are calling on banks and other financial players to come clean about the exposure of their books to such risks. The ECB and other regulators have made it clear there is a long way to go on this.

 

(Editing by Giles Elgood)

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