The beaver may be an unlikely agent of climate change, but the cuddly-looking creatures are transforming the Arctic landscape in a way that could be exacerbating global warming, a new study has suggested.
With their sharp teeth, beavers fell trees and shrubs and build dams, which flood small valleys and form new lakes that can cover several hectares of land.
These new water bodies contribute to the thawing of the frozen permafrost soil, which is a huge natural reservoir of methane — a potent greenhouse gas.
In the past few years, scientists have spotted beavers in the Alaskan tundra where they’ve previously never been seen before — and the animals have been enjoying a dam-building boom in their new neighborhood, according to the study of high-resolution satellite imagery published in the journal Environmental Research Letters Monday.
They also seem to be building their dams and creating new lakes in the very locations that are most likely to intensify the thawing of the permafrost.
“We’re seeing exponential growth there. The number of these structures doubles roughly every four years,” said Ingmar Nitze, a researcher from the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research in Potsdam, Germany, and author of the study.
“Their methods are extremely effective.”
The study found that the number of beaver dams in a 100-square-kilometer area surrounding the city of Kotzebue, northwest Alaska, increased from just two in 2002 to 98 in 2019 — a 5,000% increase. Beaver dams in the larger, 430-square-kilometer area on Alaska’s Baldwin Peninsula have increased from 94 in 2010 to 174 in 2013 and 409 last year.
“It’s possible to see them and spot them (the dams) in the imagery. It’s also possible to see the development of lakes. They had a distinctive signal,” said Nitze.
BLAME IT ON THE BEAVERS?
Several different factors explain why the beavers have occupied a region they wouldn’t normally call home, said Nitze. One is climate change, which is altering the typically treeless tundra.
“We see an increase in vegetation. There are more shrubs coming in there so all the stuff beavers need to build their dams, or as food, is there,” he said. Furthermore, the lakes, which used to freeze solid, now offer friendlier conditions for beavers, as a result of their thinner seasonal winter ice cover
The tundra is also not the beavers’ usual habitat so they face no predators or competition for resources, plus the animals are better protected now by U.S. federal law and hunted far less by humans than they used to be.
Because the lakes the beavers create contain water that is warmer than the surrounding soil, the new bodies of water accelerate the permafrost thawing.
“The thing about permafrost is that water interacts very strongly with the frozen ground beneath it,” Nitze said. “The more surface water you have, the worse it is for the permafrost–because in the winter the cold air cannot penetrate again into the ground, and the water stores a lot of the heat and can even penetrate it into the ground,” he said.
Lakes and water bodies influenced by beavers accounted for two-thirds of the 8.3% increase in total surface water area in the Kotzebue study area during a 17-year period, the study found.
The beavers also seemed to intuitively target drained lake basins, turbocharging the impact they had on the landscape and the permafrost.
“It’s a special landscape. There’s typically a lot of lakes but they are dynamic so they can drain and leave a lot of basins … and these beavers are smart enough to block the outlet and refill the basin again. They dam up a lot of area with minimum effort.”
Nitze said the beaver dam-building boom was also likely taking place in the Canadian tundra, and could also be happening in Siberia.
“We’re working to expand the analysis on a bigger scale.”
“There are a lot of people trying to quantify methane and CO2 emissions from lakes in the Arctic but not specifically yet from beaver lakes,” said Nitze.
“It’s a very new topic and something we have uncovered over the past few years. Beavers can have a quite significant impact on these landscapes, so there’s no real quantification yet for these lakes but it will be done in the future.”
NAIROBI, Kenya (AP) — The body of Ugandan Olympic athlete Rebecca Cheptegei — who died after being set on fire by her partner in Kenya — was received Friday by family and anti-femicide crusaders, ahead of her burial a day later.
Cheptegei’s family met with dozens of activists Friday who had marched to the Moi Teaching and Referral Hospital’s morgue in the western city of Eldoret while chanting anti-femicide slogans.
She is the fourth female athlete to have been killed by her partner in Kenya in yet another case of gender-based violence in recent years.
Viola Cheptoo, the founder of Tirop Angels – an organization that was formed in honor of athlete Agnes Tirop, who was stabbed to death in 2021, said stakeholders need to ensure this is the last death of an athlete due to gender-based violence.
“We are here to say that enough is enough, we are tired of burying our sisters due to GBV,” she said.
It was a somber mood at the morgue as athletes and family members viewed Cheptegei’s body which sustained 80% of burns after she was doused with gasoline by her partner Dickson Ndiema. Ndiema sustained 30% burns on his body and later succumbed.
Ndiema and Cheptegei were said to have quarreled over a piece of land that the athlete bought in Kenya, according to a report filed by the local chief.
Cheptegei competed in the women’s marathon at the Paris Olympics less than a month before the attack. She finished in 44th place.
Cheptegei’s father, Joseph, said that the body will make a brief stop at their home in the Endebess area before proceeding to Bukwo in eastern Uganda for a night vigil and burial on Saturday.
“We are in the final part of giving my daughter the last respect,” a visibly distraught Joseph said.
He told reporters last week that Ndiema was stalking and threatening Cheptegei and the family had informed police.
Four in 10 women or an estimated 41% of dating or married Kenyan women have experienced physical or sexual violence perpetrated by their current or most recent partner, according to the Kenya Demographic and Health Survey 2022.
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.”
VICTORIA – The British Columbia government is partnering with a bear welfare group to reduce the number of bears being euthanized in the province.
Nicholas Scapillati, executive director of Grizzly Bear Foundation, said Monday that it comes after months-long discussions with the province on how to protect bears, with the goal to give the animals a “better and second chance at life in the wild.”
Scapillati said what’s exciting about the project is that the government is open to working with outside experts and the public.
“So, they’ll be working through Indigenous knowledge and scientific understanding, bringing in the latest techniques and training expertise from leading experts,” he said in an interview.
B.C. government data show conservation officers destroyed 603 black bears and 23 grizzly bears in 2023, while 154 black bears were killed by officers in the first six months of this year.
Scapillati said the group will publish a report with recommendations by next spring, while an independent oversight committee will be set up to review all bear encounters with conservation officers to provide advice to the government.
Environment Minister George Heyman said in a statement that they are looking for new ways to ensure conservation officers “have the trust of the communities they serve,” and the panel will make recommendations to enhance officer training and improve policies.
Lesley Fox, with the wildlife protection group The Fur-Bearers, said they’ve been calling for such a committee for decades.
“This move demonstrates the government is listening,” said Fox. “I suspect, because of the impending election, their listening skills are potentially a little sharper than they normally are.”
Fox said the partnership came from “a place of long frustration” as provincial conservation officers kill more than 500 black bears every year on average, and the public is “no longer tolerating this kind of approach.”
“I think that the conservation officer service and the B.C. government are aware they need to change, and certainly the public has been asking for it,” said Fox.
Fox said there’s a lot of optimism about the new partnership, but, as with any government, there will likely be a lot of red tape to get through.
“I think speed is going to be important, whether or not the committee has the ability to make change and make change relatively quickly without having to study an issue to death, ” said Fox.
This report by The Canadian Press was first published Sept. 9, 2024.
