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How do polar bears eat when there's no sea ice? Not well, study finds – CBC News

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For polar bears, summertime is definitely not when the living is easy.

They are apex predators, mighty hunters, and as Inuit and research scientists have long known, they prefer a good fatty meal of seal, caught from the sea ice.

But during the times of the year when there is no sea ice — and those times are getting longer, due to human-caused climate change — pickings are much more meagre.

In a new study published Tuesday in Nature Communications led by the U.S. Geological Survey (USGS), scientists used GPS tracking, video collars, blood chemistry and other data to track the lives of 20 polar bears over three summer weeks near Churchill, Man.

Some bears, as expected, stayed on land and did very little, conserving energy and living off fat reserves, almost like hibernation.

Twenty bears were fitted with camera collars and tracked using GPS for about three weeks each, to see what they ate and did when they couldn’t use sea ice to hunt. Some foraged much of the day, roaming and swimming, but others stayed put on land to conserve energy. (Anthony Pagano/U.S. Geological Survey)

Others scrambled for food, foraging for berries and plants, chomping on antlers or birds — or in the case of one three-year-old female, swimming a remarkable total of 175 kilometres in the cold waters of Hudson Bay, stopping to rest on a beluga carcass that she briefly tried to eat.

An impressive range of tactics, but nevertheless, nearly every bear lost weight — an average of about a kilogram per day.

“What we found was that they had all these different behaviours and a lot of energetic strategies and none of that was able to prevent weight loss,” said co-author Karyn Rode, a research wildlife biologist with the U.S. Geological Survey’s Alaska Science Center who has studied polar bears for more than 25 years.

“What our study was really getting at was what are the limitations to polar bears’ ability to adapt.” 

WATCH | Collar footage shows how bears eat: [embedded content]

Risk of starvation on land

Polar bears do have a reputation as resilient creatures, adaptable or even opportunistic as predators.

In a 2022 report from Polar Knowledge Canada, Inuit knowledge keepers from the Nunavut communities of Pangnirtung and Kimmirut shared how bear movements change without ice.

“When the sea ice is formed the bears are out on the ice more. When the ice is gone you cannot tell where the bears are,” said Joe Arlooktoo of Kimmirut in the report, noting it depends on where their prey is.

Multiple polar bears on a beach.
An image captured by one a camera collars shows several bears on the beach near Churchill. During the study period that tracked the bears for about three weeks in August and September, some roamed the shoreline looking for food. (U.S. Geological Survey)

The new study was inspired in part by observations from Arctic communities, said Rode. Those observations prompted the scientists from USGS, Washington State University and Environment and Climate Change Canada (ECCC) to quantify those movements, in terms of energy and food intake.

The tracking only lasted about three weeks for each bear, during August and September of 2019, 2021 and 2022.

But the researchers also calculated what might come next: how long the bears could go on if they didn’t find more calories somewhere. 

Some had the fat reserves to survive, but others, the numbers suggest, would approach starvation before the end of November. That’s when, on average over the previous decade, the sea ice reforms in western Hudson Bay.

Only one of the 20 bears, a young male polar bear, gained weight during the study.

While his video collar failed, blood tests showed the four-year-old scored the one high-fat food source polar bears might find on land: a large marine mammal carcass that washed up, likely a seal or beluga.

“Unless they can encounter something like that, we wouldn’t anticipate that the weight loss we saw would be any different during other parts of the year when they’re on land,” said Rode.

University of Alberta professor Andrew Derocher, who did not take part in this research but peer-reviewed the paper, has studied polar bears across the Arctic for more than 40 years, and first wrote about how climate change impacts polar bears three decades ago.

He says the new study takes an “elegant approach,” pulling together many types of data to confirm what ice-free periods mean for polar bears.

“There’s really very little indication that there’s enough food on land for polar bears to make a living,” said Derocher.

Biologist holds the mouth open on a tranquilized polar bear for research purposes.
Biologist Andrew Derocher has studied polar bears in Hudson Bay and elsewhere for more than 40 years. When he started, he said the population there was ‘fat and happy,’ but more recently, declining sea ice has made hunting more difficult. (Submitted by Andrew Derocher)

When he started work in Churchill in the 1980s, he says the bears were “fat and happy.” 

On land, bears were killing birds, eating eggs, or foraging for plants, their teeth stained with blueberries. But they didn’t have to worry, he said, unlike some of the more vigorous, or perhaps desperate, foragers observed in the current study. 

“The bears are doing what they’ve always done,” said Derocher.

“What’s clear from this … new study, is that whatever bag of tricks they’ve had, and they’ve been using them for probably thousands and thousands of years, it’s not gonna be enough.”

Large polar bear among plants
The polar bear lifestyle involves packing on weight when hunting is possible on the sea ice, says Derocher, a case of ‘survival of the fattest’ so the bear doesn’t starve when there’s not much other than plants and berries on the menu. (David McGeachy)

Limits of adaptation

Polar bears are classified as a species of special concern by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC), and as vulnerable by the International Union for Conservation of Nature (IUCN) — primarily due to loss of sea ice.

There are 19 recognized sub-populations of polar bears globally. While some have rebounded from hunting-related losses, there’s evidence two have already seen declines related to sea ice, according to the IUCN, including the western Hudson Bay group near Churchill.


“Another two to three decades of warming may be enough to push the population over the edge, where the rate of decline is accelerated and the population rapidly gets much smaller than it currently is,” said Derocher. 

By mid-century, polar bears may not be able to survive as far south as Churchill, he said, a future also forecast in a 2012 review he co-authored with legendary polar bear researcher Ian Stirling.

Bear on beach with grass
There’s evidence of sea-ice related declines in two subpopulations of polar bears, including those of the western Hudson Bay, according to the International Union for Conservation of Nature. (Andrew Derocher )

Beyond cutting emissions to slow warming, Derocher says humans can help polar bears survive by limiting other types of mortality — like shooting problem bears. Some Arctic communities have followed the example of Churchill, Man., by securing garbage and using non-lethal tactics to keep bears away without killing them.

Further north, the prime hunting ground of sea ice will stick around longer, said Derocher, but it won’t be spared by climate change. 

“Ultimately, the Arctic is warming in its totality and all populations are going to be affected by sea ice loss going forward in time.”

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Here’s how Helene and other storms dumped a whopping 40 trillion gallons of rain on the South

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More than 40 trillion gallons of rain drenched the Southeast United States in the last week from Hurricane Helene and a run-of-the-mill rainstorm that sloshed in ahead of it — an unheard of amount of water that has stunned experts.

That’s enough to fill the Dallas Cowboys’ stadium 51,000 times, or Lake Tahoe just once. If it was concentrated just on the state of North Carolina that much water would be 3.5 feet deep (more than 1 meter). It’s enough to fill more than 60 million Olympic-size swimming pools.

“That’s an astronomical amount of precipitation,” said Ed Clark, head of the National Oceanic and Atmospheric Administration’s National Water Center in Tuscaloosa, Alabama. “I have not seen something in my 25 years of working at the weather service that is this geographically large of an extent and the sheer volume of water that fell from the sky.”

The flood damage from the rain is apocalyptic, meteorologists said. More than 100 people are dead, according to officials.

Private meteorologist Ryan Maue, a former NOAA chief scientist, calculated the amount of rain, using precipitation measurements made in 2.5-mile-by-2.5 mile grids as measured by satellites and ground observations. He came up with 40 trillion gallons through Sunday for the eastern United States, with 20 trillion gallons of that hitting just Georgia, Tennessee, the Carolinas and Florida from Hurricane Helene.

Clark did the calculations independently and said the 40 trillion gallon figure (151 trillion liters) is about right and, if anything, conservative. Maue said maybe 1 to 2 trillion more gallons of rain had fallen, much if it in Virginia, since his calculations.

Clark, who spends much of his work on issues of shrinking western water supplies, said to put the amount of rain in perspective, it’s more than twice the combined amount of water stored by two key Colorado River basin reservoirs: Lake Powell and Lake Mead.

Several meteorologists said this was a combination of two, maybe three storm systems. Before Helene struck, rain had fallen heavily for days because a low pressure system had “cut off” from the jet stream — which moves weather systems along west to east — and stalled over the Southeast. That funneled plenty of warm water from the Gulf of Mexico. And a storm that fell just short of named status parked along North Carolina’s Atlantic coast, dumping as much as 20 inches of rain, said North Carolina state climatologist Kathie Dello.

Then add Helene, one of the largest storms in the last couple decades and one that held plenty of rain because it was young and moved fast before it hit the Appalachians, said University of Albany hurricane expert Kristen Corbosiero.

“It was not just a perfect storm, but it was a combination of multiple storms that that led to the enormous amount of rain,” Maue said. “That collected at high elevation, we’re talking 3,000 to 6000 feet. And when you drop trillions of gallons on a mountain, that has to go down.”

The fact that these storms hit the mountains made everything worse, and not just because of runoff. The interaction between the mountains and the storm systems wrings more moisture out of the air, Clark, Maue and Corbosiero said.

North Carolina weather officials said their top measurement total was 31.33 inches in the tiny town of Busick. Mount Mitchell also got more than 2 feet of rainfall.

Before 2017’s Hurricane Harvey, “I said to our colleagues, you know, I never thought in my career that we would measure rainfall in feet,” Clark said. “And after Harvey, Florence, the more isolated events in eastern Kentucky, portions of South Dakota. We’re seeing events year in and year out where we are measuring rainfall in feet.”

Storms are getting wetter as the climate change s, said Corbosiero and Dello. A basic law of physics says the air holds nearly 4% more moisture for every degree Fahrenheit warmer (7% for every degree Celsius) and the world has warmed more than 2 degrees (1.2 degrees Celsius) since pre-industrial times.

Corbosiero said meteorologists are vigorously debating how much of Helene is due to worsening climate change and how much is random.

For Dello, the “fingerprints of climate change” were clear.

“We’ve seen tropical storm impacts in western North Carolina. But these storms are wetter and these storms are warmer. And there would have been a time when a tropical storm would have been heading toward North Carolina and would have caused some rain and some damage, but not apocalyptic destruction. ”

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Follow AP’s climate coverage at https://apnews.com/hub/climate

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Follow Seth Borenstein on Twitter at @borenbears

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Associated Press climate and environmental coverage receives support from several private foundations. See more about AP’s climate initiative here. The AP is solely responsible for all content.

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‘Big Sam’: Paleontologists unearth giant skull of Pachyrhinosaurus in Alberta

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It’s a dinosaur that roamed Alberta’s badlands more than 70 million years ago, sporting a big, bumpy, bony head the size of a baby elephant.

On Wednesday, paleontologists near Grande Prairie pulled its 272-kilogram skull from the ground.

They call it “Big Sam.”

The adult Pachyrhinosaurus is the second plant-eating dinosaur to be unearthed from a dense bonebed belonging to a herd that died together on the edge of a valley that now sits 450 kilometres northwest of Edmonton.

It didn’t die alone.

“We have hundreds of juvenile bones in the bonebed, so we know that there are many babies and some adults among all of the big adults,” Emily Bamforth, a paleontologist with the nearby Philip J. Currie Dinosaur Museum, said in an interview on the way to the dig site.

She described the horned Pachyrhinosaurus as “the smaller, older cousin of the triceratops.”

“This species of dinosaur is endemic to the Grand Prairie area, so it’s found here and nowhere else in the world. They are … kind of about the size of an Indian elephant and a rhino,” she added.

The head alone, she said, is about the size of a baby elephant.

The discovery was a long time coming.

The bonebed was first discovered by a high school teacher out for a walk about 50 years ago. It took the teacher a decade to get anyone from southern Alberta to come to take a look.

“At the time, sort of in the ’70s and ’80s, paleontology in northern Alberta was virtually unknown,” said Bamforth.

When paleontogists eventually got to the site, Bamforth said, they learned “it’s actually one of the densest dinosaur bonebeds in North America.”

“It contains about 100 to 300 bones per square metre,” she said.

Paleontologists have been at the site sporadically ever since, combing through bones belonging to turtles, dinosaurs and lizards. Sixteen years ago, they discovered a large skull of an approximately 30-year-old Pachyrhinosaurus, which is now at the museum.

About a year ago, they found the second adult: Big Sam.

Bamforth said both dinosaurs are believed to have been the elders in the herd.

“Their distinguishing feature is that, instead of having a horn on their nose like a triceratops, they had this big, bony bump called a boss. And they have big, bony bumps over their eyes as well,” she said.

“It makes them look a little strange. It’s the one dinosaur that if you find it, it’s the only possible thing it can be.”

The genders of the two adults are unknown.

Bamforth said the extraction was difficult because Big Sam was intertwined in a cluster of about 300 other bones.

The skull was found upside down, “as if the animal was lying on its back,” but was well preserved, she said.

She said the excavation process involved putting plaster on the skull and wooden planks around if for stability. From there, it was lifted out — very carefully — with a crane, and was to be shipped on a trolley to the museum for study.

“I have extracted skulls in the past. This is probably the biggest one I’ve ever done though,” said Bamforth.

“It’s pretty exciting.”

This report by The Canadian Press was first published Sept. 25, 2024.

The Canadian Press. All rights reserved.

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The ancient jar smashed by a 4-year-old is back on display at an Israeli museum after repair

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TEL AVIV, Israel (AP) — A rare Bronze-Era jar accidentally smashed by a 4-year-old visiting a museum was back on display Wednesday after restoration experts were able to carefully piece the artifact back together.

Last month, a family from northern Israel was visiting the museum when their youngest son tipped over the jar, which smashed into pieces.

Alex Geller, the boy’s father, said his son — the youngest of three — is exceptionally curious, and that the moment he heard the crash, “please let that not be my child” was the first thought that raced through his head.

The jar has been on display at the Hecht Museum in Haifa for 35 years. It was one of the only containers of its size and from that period still complete when it was discovered.

The Bronze Age jar is one of many artifacts exhibited out in the open, part of the Hecht Museum’s vision of letting visitors explore history without glass barriers, said Inbal Rivlin, the director of the museum, which is associated with Haifa University in northern Israel.

It was likely used to hold wine or oil, and dates back to between 2200 and 1500 B.C.

Rivlin and the museum decided to turn the moment, which captured international attention, into a teaching moment, inviting the Geller family back for a special visit and hands-on activity to illustrate the restoration process.

Rivlin added that the incident provided a welcome distraction from the ongoing war in Gaza. “Well, he’s just a kid. So I think that somehow it touches the heart of the people in Israel and around the world,“ said Rivlin.

Roee Shafir, a restoration expert at the museum, said the repairs would be fairly simple, as the pieces were from a single, complete jar. Archaeologists often face the more daunting task of sifting through piles of shards from multiple objects and trying to piece them together.

Experts used 3D technology, hi-resolution videos, and special glue to painstakingly reconstruct the large jar.

Less than two weeks after it broke, the jar went back on display at the museum. The gluing process left small hairline cracks, and a few pieces are missing, but the jar’s impressive size remains.

The only noticeable difference in the exhibit was a new sign reading “please don’t touch.”

The Canadian Press. All rights reserved.

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