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Industry, mild winters clear way for white-tailed deer 'invasion' in Alberta's boreal forest – CBC.ca

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Herds of invasive white-tailed deer continue to migrate north in Alberta’s boreal forest — bolstered by milder winters and human development that cuts through the vast wilderness, a new study suggests. 

The survey, recently published in the journal Nature, used 62 trail cameras to track the movements of white-tailed deer near Fort McMurray, Alta., over three years.

It’s a “deer invasion,” said Jason Fisher, study author and wildlife ecologist at the University of Victoria.

“They’re all over the landscape,” Fisher said. “They’re expanding their range. And because they’re having these negative effects on the ecosystem, they could definitely be considered invasive.” 

The cameras captured more than 141,000 images, and white-tailed deer appeared in 80 per cent of them. The survey makes clear that deer are now, by far, the most prevalent large mammal in the habitat, Fisher said.

“We’re kind of feeling around in the dark. But them being there in the numbers they currently are is definitely new, it’s definitely increased, and it’s gotten a lot worse over the last decade.” 

‘Deer don’t really belong in that landscape’

Deer are not native to the boreal forest and their populations are thriving, often at the expense of other species, including fragile populations of woodland caribou, Fisher said. 

The deer create imbalances in the natural food chain. The herds compete with other animals, devouring the boreal forest’s limited grazing lands. Their presence also draws more predators such as wolves to the area.

It’s like a caribou, white-tailed deer teeter-totter with wolves as the fulcrum.– Jason Fisher

“The deer don’t really belong in that landscape,” Fisher said. “They’re not evolved to move quickly over snow the way that caribou are, and so they’re easy targets for wolves. 

“With all these white-tailed deer around, that’s pushing wolf numbers up. With more wolves around, they’re hitting caribou harder.

“It’s like a caribou, white-tailed deer teeter-totter with wolves as the fulcrum. And that’s the big problem.” 

Higher numbers of white-tailed deer are attracting wolves to the area, putting increased pressure on fragile populations of woodland caribou. (Supplied by Jason Fisher)

Historically confined to the Eastern Seaboard, deer have been expanding their territory across the continent since European colonization. First they followed farmers, occupying open areas created when land was cleared of trees.

In their move north, they followed humans again, taking advantage of open grazing areas created by seismic lines and other industrial developments that cut through the thick bush.

“As agriculture swept across North America, white-tailed deer have come with it,” Fisher said. “The increase we’re seeing here in Alberta now is basically the continuation of that process. Alberta has had deer in the south ever since we’ve had agriculture. But the move north is a pretty recent phenomenon.” 

Local populations of deer have been able to rebound after even the harshest winters. (Supplied by Jason Fisher)

The study area — 3,000 square kilometres of white and black spruce, aspen, Jack pine and muskeg — is marked by extensive oil and gas development, logging roads, off-road trails and seismic lines. Deer have only been in the area for a couple of decades, Fisher said. 

Aerial surveys done by the province provide some information on local populations, Fisher said, but his team wanted to better understand the animals in relation to the weather and the landscape. 

According to the thousands of images captured by their cameras, deer were most numerous in areas touched by human development, he said. 

During the three-year study, the severity of winter fluctuated. Populations would soar after a mild winter, but even after a “biblical” second winter, herd numbers appeared relatively untouched, he said. 

‘This isn’t fully a climate-change problem’

Climate change and landscape change are working in tandem to drive the deer invasion, Fisher said. But the loss of mature forest to oil and gas development in the area is the biggest driver, he said.

The altered landscape has given the animals access to new foraging grounds, allowing them to withstand harsh seasons when they might normally starve, Fisher said. 

In an ongoing follow-up study he is overseeing in the Richardson Backcountry, an untouched swath of wilderness north of Fort McMurray, deer numbers are sparse. 

With milder winters expected and more development encroaching into the boreal habitat every year, white-tailed deer territory will only continue to grow, Fisher said.

“This isn’t fully a climate-change problem,” he said. “As long as there is ongoing disturbance in the landscape without restoration, then the white-tailed deer are going to be there.” 

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NASA probe leaking asteroid samples due to jammed door – Al Jazeera English

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Images beamed back to ground control revealed it caught more material than scientists anticipated and was spewing excess of flaky asteroid rocks into space.

A US probe that collected a sample from an asteroid earlier this week retrieved so much material that a rock is wedged in the container door, allowing rocks to spill back out into space.

On Tuesday, the robotic arm of the probe, OSIRIS-REx, kicked up a debris cloud of rocks on Bennu, a skyscraper-sized asteroid some 320 million kilometres (200 million miles) from Earth and trapped the material in a collection device for the return to Earth.

But images of the spacecraft’s collection head beamed back to ground control revealed it had caught more material than scientists anticipated and was spewing an excess of flaky asteroid rocks into space.

The leakage had the OSIRIS-REx mission team scrambling to stow the collection device to prevent additional spillage.

“Time is of the essence,” Thomas Zurbuchen, NASA’s associate administrator for science, told reporters on Friday.

Zurbuchen said mission teams will skip their chance to measure how much material they collected as originally planned and proceed to the stow phase, a fragile process of tucking the sample collection container in a safe position within the spacecraft without jostling out more valuable material.

NASA will not know how much material it collected until the sample capsule returns in 2023.

The troubleshooting also led mission leaders to forgo any more chances of redoing a collection attempt and instead commit to begin next March the spacecraft’s return to Earth.

“Quite honestly, we could not have performed a better collection experiment,” OSIRIS-REx’s principal investigator Dante Lauretta said.

But with the door lodged open by a rock and the “concerning” images of sample spillage, “we’re almost the victim of our own success here”, he added.

The roughly $800m, minivan-sized OSIRIS-REx spacecraft, built by Lockheed Martin, launched in 2016 to grab and return the first US sample of pristine asteroid materials.

Asteroids are among the leftover debris from the solar system’s formation some 4.5 billion years ago.

A sample could hold clues to the origins of life on Earth, scientists say.

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Asteroid samples escaping from jammed NASA spacecraft – Phys.org

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In this image taken from video released by NASA, the Osiris-Rex spacecraft touches the surface of asteroid Bennu on Tuesday, Oct. 20, 2020. (NASA via AP)

A NASA spacecraft is stuffed with so much asteroid rubble from this week’s grab that it’s jammed open and precious particles are drifting away in space, scientists said Friday.

Scientists announced the news three days after the named Osiris-Rex briefly touched asteroid Bennu, NASA’s first attempt at such a mission.

The mission’s lead scientist, Dante Lauretta of the University of Arizona, said Tuesday’s operation 200 million miles away collected far more material than expected for return to Earth—in the hundreds of grams. The sample container on the end of the robot arm penetrated so deeply into the asteroid and with such force, however, that rocks got sucked in and became wedged around the rim of the lid.

Scientists estimate the sampler pressed as much as 19 inches (48 centimeters) into the rough, crumbly, black terrain.

“We’re almost a victim of our own success here,” Lauretta said at a hastily arranged news conference.

Lauretta said there is nothing can do to clear the obstructions and prevent more bits of Bennu from escaping, other than to get the samples into their as soon as possible.

So, the flight team was scrambling to put the sample container into the capsule as early as Tuesday—much sooner than originally planned—for the long trip home.

“Time is of the essence,” said Thomas Zurbuchen, chief of NASA’s science missions.

This is NASA’s first asteroid sample-return mission. Bennu was chosen because its carbon-rich material is believed to hold the preserved building blocks of our solar system. Getting pieces from this cosmic time capsule could help scientists better understand how the planets formed billions of years ago and how life originated on Earth.

Scientists were stunned—and then dismayed—on Thursday when they saw the pictures coming from Osiris-Rex following its wildly successful touch-and-go at Bennu two days earlier.

A cloud of asteroid particles could be seen swirling around the spacecraft as it backed away from Bennu. The situation appeared to stabilize, according to Lauretta, once the robot arm was locked into place. But it was impossible to know exactly how much had already been lost.

The requirement for the $800 million-plus mission was to bring back a minimum 2 ounces (60 grams).

Regardless of what’s on board, Osiris-Rex will still leave the vicinity of the asteroid in March—that’s the earliest possible departure given the relative locations of Earth and Bennu. The samples won’t make it back until 2023, seven years after the spacecraft rocketed away from Cape Canaveral.

Osiris-Rex will keep drifting away from Bennu and will not orbit it again, as it waits for its scheduled departure.

Because of the sudden turn of events, scientists won’t know how much the sample capsule holds until it’s back on Earth. They initially planned to spin the spacecraft to measure the contents, but that maneuver was canceled since it could spill even more debris.

“I think we’re going to have to wait until we get home to know precisely how much we have,” Lauretta told reporters. “As you can imagine, that’s hard. … But the good news is we see a lot of material.”

Japan, meanwhile, is awaiting its second batch of samples taken from a different asteroid, due back in December.


Explore further

NASA spacecraft sent asteroid rubble flying in sample grab


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Two flights into Abbotsford have had recent COVID-19 exposures – Maple Ridge News

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Two flights to Abbotsford have each had a recent COVID-19 exposure, according to the B.C. Centre for Disease Control (CDC).

The agency indicates on its website that the flights involved were WestJet flight 637 from Calgary to Abbotsford on Wednesday, Oct. 14 (rows nine to 15) and Swoop flight 107 from Hamilton to Abbotsford on Monday, Oct. 19 (rows 20 to 26).

The CDC advises that anyone who was on these flights should self-monitor for symptoms for 14 days.

RELATED: Vancouver airport to pilot pre-flight COVID-19 tests for select WestJet passengers

Passengers on domestic flights are not required to self-isolate, but those who have travelled outside of Canada are required to self-isolate for 14 days upon their arrival.

Passengers seated on a plane with a case of COVID-19 that was later identified are no longer directly notified of their potential exposure. Instead, anyone who has travelled is asked to monitor the CDC website.

Passengers seated in the affected rows are considered to be at higher risk of exposure due to their proximity to the case.

RELATED: WestJet to offer full refunds for flights cancelled due to COVID-19 pandemic



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