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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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Breathtaking NASA Image Shows a Magical ‘Sea of Dunes’ on Mars

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On Thursday, NASA released a stunning photo of a sea of dunes on Mars.

It also shows wind-sculpted lines surrounding Mars’ frosty northern polar cap.

The section captured in the shot represents an area that is 31 kilometers (19 miles) wide, NASA said. The sea of dunes, however, actually covers an area as large as Texas.

The photo is a false color image, meaning that the colors are representative of temperatures. Blue represents cooler climes, and the shades of yellow mark out “sun-warmed dunes,” the US space agency wrote.

Sea of dark dunes surrounds Mars’ northern polar cap.(NASA/JPL-Caltech/ASU)

The photo is made of a combination of images captured by the Thermal Emission Imaging System instrument on the Mars Odyssey orbiter, NASA wrote.

Captured during the period from December 2002 to November 2004, the breathtaking images have been released to mark the 20th anniversary of Odyssey.

The Mars Odyssey orbiter is a robotic spacecraft circling Mars that uses a thermal imager to detect evidence of water and ice on the planet.

It was launched in 2001, making it the longest-working Mars spacecraft in history.

Source:- ScienceAlert

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Humans actually hunted large animals and ate mostly meat for 2 millions years: study – CTV News

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TORONTO —
Despite a widespread belief that humans owe their evolution to the dietary flexibility in eating both meat and vegetables, researchers in Israel suggest that early humans were actually apex predators who hunted large animals for two million years before they sought vegetables to supplement their diet.

In a study recently published in the American Journal of Physical Anthropology, academics from Tel Aviv University in Israel and the University of Minho in Portugal examined modern biology to determine if stone-age humans were specialized carnivores or generalist omnivores.

“So far, attempts to reconstruct the diet of Stone-Age humans were mostly based on comparisons to 20th century hunter-gatherer societies,” one of the study’s authors, Miki Ben-Dor, a researcher at Tel Aviv University, said in a press release.

“This comparison is futile, however, because two million years ago hunter-gatherer societies could hunt and consume elephants and other large animals – while today’s hunter gatherers do not have access to such bounty.”

Instead, the researchers looked at approximately 400 previous scientific studies on human anatomy and physiology as well as archeological evidence from the Pleistocene period, or “Ice Age” period, which began about 2.6 million years ago, and lasted until 11,700 years ago.

“We decided to use other methods to reconstruct the diet of Stone-Age humans: to examine the memory preserved in our own bodies, our metabolism, genetics and physical build,” Ben-Dor said.

“Human behaviour changes rapidly, but evolution is slow. The body remembers.”

They discovered 25 lines of evidence from the studied papers on human biology that seem to show that earlier Homo sapiens were apex predators at the top of the food chain.

For example, the academics explained that humans have a high acidity in their stomachs when compared to omnivores or even other predators, which is important for consuming animal products.

“Strong acidity provides protection from harmful bacteria found in meat, and prehistoric humans, hunting large animals whose meat sufficed for days or even weeks, often consumed old meat containing large quantities of bacteria, and thus needed to maintain a high level of acidity,” Ben-Dor said.

Another piece of evidence, according to the study, is the structure of human fat cells.

“In the bodies of omnivores, fat is stored in a relatively small number of large fat cells, while in predators, including humans, it’s the other way around: we have a much larger number of smaller fat cells,” Ben-Dor said.

HUNTING EXPERTS

In addition to the evidence they collected by studying human biology, the researchers said archeological evidence from the Pleistocene period supports their theory.

In one example, the study’s authors examined stable isotopes in the bones of prehistoric humans as well as their hunting practices and concluded these early humans specialized in hunting large and medium-sized animals with high fat content.

“Comparing humans to large social predators of today, all of whom hunt large animals and obtain more than 70% of their energy from animal sources, reinforced the conclusion that humans specialized in hunting large animals and were in fact hypercarnivores,” the academics noted.

Ben-Dor said Stone-Age humans’ expertise in hunting large animals played a major role in the extinction of certain large animals, such as mammoths, mastodons, and giant sloths.

“Most probably, like in current-day predators, hunting itself was a focal human activity throughout most of human evolution. Other archeological evidence – like the fact that specialized tools for obtaining and processing vegetable foods only appeared in the later stages of human evolution – also supports the centrality of large animals in the human diet, throughout most of human history,” he said.

This is not to say, however, that humans during this period didn’t eat any plants. Ben-Dor said they also consumed plants, but they weren’t a major component of their diet until the end of the era when the decline of animal food sources led humans to increase their vegetable intake.

Eventually, the researchers said humans had no choice but to domesticate both plants and animals and become farmers.

Ran Barkai, one of the study’s authors and a professor at Tel Aviv University, said their findings have modern-day implications.

“For many people today, the Paleolithic diet is a critical issue, not only with regard to the past, but also concerning the present and future. It is hard to convince a devout vegetarian that his/her ancestors were not vegetarians, and people tend to confuse personal beliefs with scientific reality,” he said. 

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Marimaca Copper: First Drill Hole Intersects Broad Zone of Sulphide Copper Mineralization at Marimaca – Junior Mining Network

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VANCOUVER, British Columbia, April 07, 2021 (GLOBE NEWSWIRE) — Marimaca Copper Corp. (“Marimaca Copper” or the “Company”) (TSX: MARI) is pleased to announce the assay results of the first drill hole of a five-hole program targeting extensions of sulphide mineralization below the Company’s flagship Marimaca Oxide Deposit (“MOD”). Drilling encountered a broad zone of chalcopyrite and minor chalcocite, indicating potential for economic sulphide mineralization.

Highlights

  • Drill hole MAR-125 intersected 116m (expected approximate true width) at an average grade of 0.51% CuT from 162m, including two higher grade zones of:
    • 20m with an average grade of 0.77% CuT from 162m; and
    • 42m with an average grade of 0.92% CuT from 236m.
  • Intersection represents a significantly broader zone of mineralization than anticipated from earlier, nearby, sulphide drilling intersections
  • First drill hole of an initial five-hole campaign to test for extensions of mineralization at depth
    • First hole designed to extend mineralization closer to sulphide zones identified in historical drilling
    • Remaining four holes designed to test the limits of mineralization with step outs of approximately 300m at depth and between 400m and 700m along strike to the north and south of the first hole
  • Sulphide drilling to be completed shortly, with assay results on remaining holes expected by the end of April 2021
  • In response to escalating COVID situation in Chile, the Company has initiated a break in drilling which is not expected to impact the original target of testing all identified targets by the end of 1H 2021.

Sergio Rivera, VP Exploration of Marimaca Copper, commented:

“The results of the first hole of this initial campaign are extremely pleasing, exceeding both the widths and grades we had projected for this zone based on earlier drilling completed nearby. The broad intercept of chalcopyrite mineralization shows good continuity downhole, with potentially economic grades, especially at the bottom of the intercept.

“The drilling has also provided additional geological information, which we are using to refine our understanding of the controls of mineralization and to inform future drillhole locations, targeting mineralized extensions at depth and along strike.

“The next four holes are significant step outs from the known mineralized zones outside of the Mineral Resource Estimate area and are designed to test the limits of the mineralized body, both at depth and along strike. The second hole will be collared approximately 350m to the east of MAR-125, targeting mineralization up to 300m below the current deepest mineralization. The third, fourth and fifth holes will be located between 400m and 700m to the north and south of MAR-125, aiming to test for extensions along strike.

“This first hole has provided encouragement that there is potential for economically interesting sulphide mineralization at Marimaca, while the next four drill holes are designed to better delineate the tonnage potential of this.”

Discussion of Campaign Objectives and Results

The current five-hole drilling campaign at the Marimaca Copper Project is designed to test for extensions to mineralization below the MOD. Based on the structural controls of the mineralization, the results of previous geophysical campaigns and earlier drilling, which extended beyond the current Mineral Resource Estimate (“MRE”) area, the Company believes there is the potential for extensions of the mineralized body at depth across the full strike length of the MOD. All drill holes will be drilled at an azimuth of 270o and at -60o, roughly perpendicular to the north-south striking, easterly dipping mineralizing structures. Intercepts should, therefore, be relatively close to the true width of the mineralization.

The first drill hole (MAR-125) encountered a broad zone of dominantly chalcopyrite mineralization with some pyrite and minor chalcocite over a down hole width (expected to be equivalent to approximate true width) of 116m with an average grade of 0.51% CuT. This includes two zones of higher-grade mineralization including 20m with an average grade of 0.77% CuT and 42m with an average grade of 0.92% CuT at the end of the mineralized intercept. The hole was collared to test mineralization approximately 100m to the east of the earlier hole ATR-82, which intersected 44m of sulphide copper mineralization with an average grade of 1.05% CuT, and 200m and 300m east of holes ATR-93 and ATR-94 respectively, which both intersected mineralization with true widths of around 40m with average grades above 1.0% CuT. MAR-125 has demonstrated an extension to this higher-grade mineralization and provides further areas to target for follow up drilling.

MAR-125 is located in the center of the current MRE area, proximal to a zone of relatively high-grade sulphide mineralization intercepted in several drill holes over widths of between 30m and 50m. The remaining four drill holes have been located to test the limits of the mineralization by stepping out significantly at depth and along strike beyond the current MRE area. The collar of the second hole, MAS-03, is located approximately 100m to the south and 350m to the east of MAR-125 and is aimed to intersect mineralization approximately 300m below MAR-125. MAS-02 and MAS-04, located approximately 400m and 700m, respectively, south of MAR-125, and are planned as significant step outs along strike, targeting the conductivity high noted in the IP survey completed across the MOD

Figure 2

Sampling and Assay Protocol

True widths cannot be determined with the information available at this time. Marimaca Copper RC holes were sampled on a 2-metre continuous basis, with dry samples riffle split on site and one quarter sent to the Andes Analytical Assay preparation laboratory in Calama and the pulps then sent to the same company laboratory in Santiago for assaying. A second quarter was stored on site for reference. Samples were prepared using the following standard protocol: drying; crushing to better than 85% passing -10#; homogenizing; splitting; pulverizing a 500-700g subsample to 95% passing -150#; and a 125g split of this sent for assaying. All samples were assayed for CuT (total copper), CuS (acid soluble copper) by AAS. A full QA/QC program, involving insertion of appropriate blanks, standards and duplicates was employed with acceptable results. Pulps and sample rejects are stored by Marimaca Copper for future reference.

Qualified Person

The technical information in this news release, including the information that relates to geology, drilling and mineralization was prepared under the supervision of, or has been reviewed by Sergio Rivera, Vice President of Exploration, Marimaca Copper Corp, a geologist with more than 36 years of experience and a member of the Colegio de Geólogos de Chile and of the Institute of Mining Engineers of Chile, and who is the Qualified Person for the purposes of NI 43-101 responsible for the design and execution of the drilling program.

Mr. Rivera confirms that he has visited the Marimaca Project on numerous occasions, is responsible for the information contained in this news release and consents to its publication.

Contact Information
For further information please visit www.marimaca.com or contact:

Tavistock
+44 (0) 207 920 3150
Jos Simson/Emily Moss 
This email address is being protected from spambots. You need JavaScript enabled to view it. 

Forward Looking Statements

This news release includes certain “forward-looking statements” under applicable Canadian securities legislation. These statements relate to future events or the Company’s future performance, business prospects or opportunities. Forward-looking statements include, but are not limited to, the impact of a rebranding of the Company, the future development and exploration potential of the Marimaca Project. Actual future results may differ materially. There can be no assurance that such statements will prove to be accurate, and actual results and future events could differ materially from those anticipated in such statements. Forward-looking statements reflect the beliefs, opinions and projections on the date the statements are made and are based upon a number of assumptions and estimates that, while considered reasonable by Marimaca Copper, are inherently subject to significant business, economic, competitive, political and social uncertainties and contingencies. Many factors, both known and unknown, could cause actual results, performance or achievements to be materially different from the results, performance or achievements that are or may be expressed or implied by such forward-looking statements and the parties have made assumptions and estimates based on or related to many of these factors. Such factors include, without limitation: risks related to share price and market conditions, the inherent risks involved in the mining, exploration and development of mineral properties, the uncertainties involved in interpreting drilling results and other geological data, fluctuating metal prices, the possibility of project delays or cost overruns or unanticipated excessive operating costs and expenses, uncertainties related to the necessity of financing, the availability of and costs of financing needed in the future as well as those factors disclosed in the Company’s documents filed from time to time with the securities regulators in the Provinces of British Columbia, Alberta, Saskatchewan, Manitoba, Ontario, New Brunswick, Nova Scotia, Prince Edward Island and Newfoundland and Labrador. Accordingly, readers should not place undue reliance on forward-looking statements. Marimaca Copper undertakes no obligation to update publicly or otherwise revise any forward-looking statements contained herein whether as a result of new information or future events or otherwise, except as may be required by law.


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