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Canada jay numbers in southern Ontario decreasing because of climate change, study suggests – CBC.ca

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The number of Canada jays in southern Ontario is decreasing because of more frequent freeze-thaw days due to climate change, according to recently published research.

The birds’ winter food stock was compromised when fall temperatures fluctuated. The food would defrost, grow bacteria and in some cases become inedible.

And that had an effect on the birds’ reproduction and population numbers, University of Guelph researchers found in a study recently published in the scientific journal Global Change Biology.

“If your food is being spoiled, you have less food that you can devote to survival and reproduction,” said Alex Sutton, who was a PhD student at the University of Guelph when he co-led the study with Ryan Norris, an associate professor in the university’s department of integrative biology.

“What seems to be happening is that they need to decide either to survive or to reproduce,” said Sutton, now a post-doctoral fellow at Kansas State University.

If the warming pattern in the fall continues to affect reproduction and food supply, the birds could become locally extinct from Algonquin Provincial Park and other southern Ontario ranges, said Sutton, who is based in Manhattan, Kansas, about 94 kilometres west of the capital Topeka.

Number of nestlings declined

Canada jays are known for storing their food —  which can be anything from berries to roadkill meat —  in nearby trees for the winter.

However, when their food supply degraded with the freeze-thaw weather, the non-migratory birds produced fewer young or hatchlings in poorer condition, Sutton said. 

University of Guelph researcher Alex Sutton feeding a Canada jay in Algonquin Provincial Park. (Submitted by Koley Freeman)

“On average, the number of nestlings has declined over time, or at least in years where there’s unfavourable fall conditions,” he said.

And that has long-term implications, according to the study with data spanning almost 40 years.  

The study looked at the birds in a small part of the park, about 280 kilometres northeast of Toronto. However, the Canada jay population that has been studied in the park has ranged from a high of 85 to now between 40 and 50 depending on the year, Sutton said.  

“Reproduction was really the key thing that was promoting this decline in Algonquin,” he said.

The study used bird population numbers from 1980 to 2018, as well as environment data recorded in Algonquin Provincial Park since 1977 to look at the effects of the fluctuations in temperatures on the bird population and their food supply.  

Between 1980 and 1996, which had 10 years of above-average freeze-thaw cycles, the researchers found that the birds’ numbers dropped significantly.

Although there were fewer above-average number of freeze-thaw cycles and more breeding success in later years, the birds’ numbers never rebounded from “a period of poor environmental conditions that occurred several decades prior,” according to the study. 

David Bird, a retired professor of wildlife biology at Montreal’s McGill University, said the amount of detailed data included in the study is impressive but the results are troubling.

“There’s still lots of challenges out there,” he said. “Climate change is very worrisome.”

Birds could go north

Sutton and Bird believe the effects of climate change on the birds’ food supply could eventually push the species further north.

The Canada jay can be found in every province and territory, but little is known about the effects of climate change on northern populations. 

The study said citizen science databases, like Christmas bird counts, “help to fill this gap in our knowledge and be used to estimate population trends at more northern latitudes.” The bird is important to many Canadians, so much so there’s a campaign led by Bird and others, like Norris, to name the Canada jay the country’s national bird.

Sutton said it’s important that we find out more about the Canada jay. 

“I think it’s really important that we try to understand how this species is actually responding to climate change throughout its entire range,” Sutton said. 

“This could be a really key point to understanding how future population declines or even changes might occur with changing climate.”

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NASA's Perseverance Mars rover deploys wind sensor as health checks continue – Firstpost

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A fortnight since its widely-documented touch down on Mars, NASA’s Perseverance rover continues to find its bearings and stretch its numerous ‘arms’ on the Red Planet. Since the 18 February landing, the rover team has been performing a methodical battery of tests on its seven science instruments, and begun deploying the ones that work. In the latest deployment, Perseverance deployed its wind sensor, as seen in photographs captured by the navigation cameras on board.

The Perseverance rover’s navigation cameras show the wind sensor deployed. Image Credit: NASA/JPL-Caltech

The wind sensor is one of the instruments part of a weather monitoring experiment on the rover called the Mars Environmental Dynamics Analyzer (MEDA). The sensor collects data on air temperature, humidity, radiation, dust and wind around the rover, which is currently parked in its landing site – the Jezero Crater, a 45-km-wide depression in the ground that is thought to have once been home to an ancient lake and river delta.

The High Resolution Imaging Experiment (HiRISE) on NASA’s Mars Reconnaissance Orbiter, spotted Perseverance at its landing site, six days after touchdown and in the process of system checks.

Perseverance rover and the Jezero Crater around it, as seen by HiRISE on 24 February. Image Credit: HiRISE: Beautiful Mars/Twitter

Perseverance rover and the Jezero Crater around it, as seen by HiRISE on 24 February. Image Credit: HiRISE: Beautiful Mars/Twitter

From the orbiter’s vantage point over 250 kilometres away in orbit, the ground below Percy’s wheels appears to be loose, dark material, with brighter material underneath. The bright zones are visible on either side of the rover, likely “scoured clear by the descent stage rockets” during descent, as per a statement on the HiRISE website.

In late February, ESA’s Trace Gas Orbiter shared another wide view of the rover and components after its descent, littering the surface of the Red Planet. The Perseverance rover is visible in images as a relatively faint spot next to a ridge connecting to one of the smaller craters in the vicinity.

Ingenuity: Perseverance rover’s first ‘big job’

Perseverance’s first big job will be to find an airfield where its little helicopter buddy can take off, according to a Space.com report. Mission controllers received the first status report from the Ingenuity Mars Helicopter attached to the belly of the rover, hours after its landing. Ingenuity will remain attached to the rover for the next several weeks, NASA had said in a statement at the time. Provided Ingenuity survives the frigid Martian nights to come, where temperatures dip to lows of minus 90 degrees Celsius, the mission team will proceed with the first flight of an aircraft on another world.

If Ingenuity manages to land successfully and remain operable, NASA may send four successors, “each building on the success of the last”, the agency said. These descendants of the Ingenuity rotorcraft can bring an aerial dimension to exploration of Mars.

Also read: ESA’s Trace Gas Orbiter, NASA’s HiRISE catch stunning glimpses of Perseverance rover on Mars

NASA shares video, audio of Perseverance Mars landing

Ingenuity helicopter reports in

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Asking 'Where do you think you got COVID?' helps contact tracers zero in on superspreader events – CBC.ca

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The painstaking detective work of contact tracing usually starts with an infected person and works forward, asking who has that person seen since they became potentially contagious with COVID-19.

But that mainstay of public health has a less high-profile cousin that’s become instrumental in spotting superspreader events quickly — working in reverse.

“Instead of asking who did that person potentially give the virus to, you’re asking where did that person get the virus?” said Dr. Trevor Arnason, associate medical officer of health with Ottawa Public Health.

“It makes you become better at finding people who have COVID-19 who you might not have known about.”

COVID-19 tends to spread explosively in situations where the virus can infect a bunch of people all at once, public health experts say, which is where what’s known as backward tracing comes in handy.

Ottawa Public Health cottoned on to the benefits of backward tracing when emerging evidence from Japan showed how focusing on where a person got COVID-19 and going back to that location helped to find many more who were infected.

“We started more systematically asking everybody, ‘Where do you think you got it? Or who do you think you got this from? And then we started working back from those places. You start to notice these patterns, which we’ve put together in infographics that we’ve shared with the public,” Arnason said.

Infographics tracing how many were affected from one indoor wedding allowed the public to see how seemingly disparate locations tied together, resulting in 22 people from eight households being affected in two weeks.

“Backward contact tracing is used to find the superspreading events. That’s the main goal.”

Ashleigh Tuite, an infectious diseases epidemiologist in Toronto, said most people who are infected don’t pass it to others. 

But the instances where an individual goes on to transmit to many others likely reflect how coronavirus transmission clusters at a particular location or environment.

An indoor gym where those working out are unmasked, breathing heavily in what may not be the best ventilated conditions is one example.

“It’s clear that telling people to wear masks when they move around a gym, but not when they’re exercising, which I think has been the protocol in a lot of places, wasn’t enough,” Tuite said. 

WATCH | Day in the life of COVID-19 contact tracers [May 2020]: 

The National’s Adrienne Arsenault spends a day with contact tracers in London, Ont., who help figure out where someone caught COVID-19 and determine who else may be at risk. 3:43

Suppressing variants

Backward contact tracing is a lot of work for public-health staff facing down outbreaks, said Tuite, but also potentially high yield.

It can be particularly helpful at the early stages an epidemic — which is long-gone for normal coronavirus, but the introduction of more-transmissible variants of concern is like a do-over, said Tuite, an assistant professor at the University of Toronto’s Dalla Lana School of Public Health.

“It’s an effective way of suppressing the growth of the variants of concern amongst this larger epidemic that’s happening,” she said.

“Overall, we have declining case counts and so if we can control sparks that are happening with the variants of concern, there is the potential to really keep it under control and at least keep case counts declining.”

This May 13, 2020, photo taken with a fisheye lens shows a list of the confirmed COVID-19 cases in Salt Lake County. The white board remains in the office as a reminder of how quickly the coronavirus spread. (Rick Bowmer/Associated Press)

Declining case counts mean hospital and health-care capacity can accommodate more surgeries and preventative care and allow the economy underpinning society to recover, too.

For now, Tuite said case counts will only decline if people restrict their interactions.

For Dr. Susy Hota, an infectious diseases specialist at Toronto’s University Health Network, keeping the variants of concern at bay is another goal of vaccinating as many people as quickly as possible.

“If we continue to allow transmission to occur, [the variants] will take over a larger and larger proportion of the market, so to speak,” said Hota, an associate professor of medicine at the University of Toronto.

Stopping spread fast

Regardless of variants, forward contact tracing to identify high-risk contacts and possible cases as aggressively as possible so they know to isolate quickly will always be a key public health tool.

For instance, a Manitoba spokesperson said they routinely collect information on where a COVID-positive case may have been exposed. But the focus is on forward contact tracing to stop spread as quickly as possible.

WATCH | Workplace physical distancing innovation:

A Calgary tech company’s device is in big demand as manufacturing companies look for ways to keep employees physically distanced while maintaining productivity. 3:09

Hota cautioned there are even more recall challenges with backward contact tracing than forward, using herself as an example.

“Do you think you were more than two metres away when you talked to that person? I think so. But I didn’t have a yardstick with me. And how long do you think you were talking? Oh, I’m terrible at that. I’ll tell you, like, five minutes. I have no idea.”

The recall problem gets amplified because to do backward contact tracing effectively means going back the full 14-day incubation period of the coronavirus. Hota does see a role for backward contact tracing in trying to pin down if there’s a single source of multiple cases, say at a meat-packing plant.

“The truth often doesn’t emerge until the epidemic is over,” Hota said.

(Tim Kindrachuk/CBC)

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SpaceX Starship poised for possible launch on Wednesday – Sports Grind Entertainment

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Hoping the third time’s the charm, a SpaceX Starship may blast off as early as Wednesday in hopes of being the first prototype to stick a landing after two previous tests ended in fiery explosions.

“The SpaceX team will attempt a high-altitude flight test of Starship serial number 10 (SN10) — our third high-altitude suborbital flight test of a Starship prototype from SpaceX’s site in Cameron County, Texas,” the company said.

As with Starships SN8 and SN9, SN10 will be powered during the ascent by three Raptor engines, each shutting down in sequence before the vehicle reaches apogee — at an altitude of about 6 miles.

“SN10 will perform a propellant transition to the internal header tanks, which hold landing propellant, before reorienting itself for reentry and a controlled aerodynamic descent,” SpaceX said.

“The Starship prototype will descend under active aerodynamic control, accomplished by independent movement of two forward and two aft flaps on the vehicle,” it explained.

“SN10’s Raptor engines will then reignite as the vehicle attempts a landing flip maneuver immediately before touching down on the landing pad adjacent to the launch mount,” according to the company.

On Feb. 2, SN9 went up in flames at the end of an otherwise successful high-altitude test from Boca Chica, Texas, reaching about 32,800 feet before turning to a horizontal “belly flop” position and performing a series of maneuvers.

It then attempted to land upright, but appeared to come in too fast and at a bad angle, ending in an explosion similar to one in December, when the company’s SN8 rocket was destroyed.

SpaceX's SN9 explosion
SpaceX’s SN9 explodes at the end of an otherwise promising test launch.
The Brownsville Herald/AP

The prototypes were developed by CEO Elon Musk’s space company in the hopes they’ll one day carry humans on missions to the moon and Mars.


Musk said he was “highly confident” the spacecraft will reach orbit “many times” and be safe for human transport by 2023.

On Tuesday, Japanese billionaire Yusaku Maezawa put out an open call for members of the public interested in boarding the SpaceX rocket that will loop around the moon that year.

On Feb. 19, an FAA spokesperson said the agency had closed the investigation into the landing mishaps, “clearing the way for the SN10 test flight pending FAA approval of license updates,” according to CNET.

“The SN9 vehicle failed within the bounds of the FAA safety analysis. Its unsuccessful landing and explosion did not endanger the public or property. All debris was contained within the designated hazard area. The FAA approved the final mishap report, including the probable causes and corrective actions,” the rep said.

Elon Musk's SpaceX
Elon Musk hopes his SpaceX company will one day carry humans on missions to the moon and Mars.
Mike Blake/REUTERS


Starship SN10 has a launch window that began at 10 a.m. EST and ends at 7 p.m.

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