Many bumblebee species have vanished from places where they were once common. Now a new Canadian-led study finds that hotter temperatures during heat waves are to blame, and uses it to predict which bumblebees are most likely to face local extinction as the climate warms.
The researchers say the technique that could also be used to make predictions for other species at risk from climate change.
In recent years (between 2000 and 2014), your chance of seeing a bumblebee at a given location declined by nearly half (46 per cent) in North America compared to in the 20th century (between 1901 and 1974), reports the study by researchers at the University of Ottawa and University College London.
“These are really severe declines,” said Peter Soroye, a PhD candidate at the University of Ottawa and the study’s lead author.
Peter Soroye, a PhD candidate at the University of Ottawa, is the lead author of the new study, which found that heat waves are linked to the huge decline in the bumblebee population across North America and Europe in recent decades. (University of Ottawa)
And that’s not just bad news for bumblebees — they’re crucial for pollinating agricultural crops from squash to berries to tomatoes, along with other flowers and plants that add colour to world, Soroye said.
“They’re probably among the best pollinators we have… they’re also really beautiful little animals,” he said. “We’d be missing a lot if they were to decline more than they have already.”
Not keeping up with climate change
Soroye’s supervisor, University of Ottawa biology Prof. Jeremy Kerr, led a previous study showing that bumblebee species have been squeezed out of warmer parts of their habitats by climate change since 1975.
“They’re not able to keep up with these changes in temperature,” said Soroye, whose followup study with Kerr echoes those results.
The fact that they were disappearing from the south pointed to climate change as a factor. But the researchers wanted to know exactly what aspect of climate change was to blame — changes in temperature, precipitation, or both?
In order to do that, they turned to a database of 550,000 bumblebee sightings from 66 species in North America and Europe between 1900 and 2015 from museum and research collections, along with sightings from citizen scientists.
The new study found that bee declines were specifically linked to hotter maximum temperatures, Soroye said.
“It’s kind of these extremes of climate throughout the year that climate change is causing.”
Bombus ternarius, commonly known as the orange-belted bumblebee, is shown on flower on Manitoulin Island, Ont. By looking at climate data and the historical range of different bumblebees, the researchers were able to predict their risk of local extinction in some parts of their range. (Peter Soroye)
While that link was clear, he also noted that bees face a lot of other challenges, such as habitat loss and pesticide use. The researchers weren’t able to determine specifically how much of the bees’ decline was due to climate change.
Nor did they know exactly how extreme heat causes bee declines. It may either cause the bees’ death direct, or it could impact the plants and flowers they rely on for food.
By looking at the highest monthly maximum temperatures at different locations over time and comparing them to bees’ historical ranges, however, the researchers could identify the temperature limits that each species could withstand, and take things a step further.
“We found we were able to predict [local] extinctions in bumblebees really well,” Soroye said.
He suggested the technique could also be used to predict where climate change will put other species at risk, including birds, mammals and reptiles.
What you can do for bees
While most bumblebees appeared not able to move into cooler areas to adapt to climate change, and few seemed to thrive in warmer temperatures, there were some exceptions.
Soroye said he and his colleagues hope to figure out why and use that information to hopefully reduce or reverse declines in other species.
In the meantime, the findings also suggests ways anyone can help bees — by providing “little refuges” from extreme temperatures in the form of fallen logs, leaf litter and plants of different heights in their gardens, Soroye said.
A bumblebee lands on a flower on Vancouver Island, B.C. Researchers say the public can help bees by providing refuges for them that include flowers that bloom at different times of year and shade where they can take shelter when it’s very hot. (Peter Soroye)
Victoria MacPhail, a PhD candidate at York University, led a 2019 study that found that by 2016, one bumblebee species, the American bumblebee, had disappeared from 70 per cent of its range and lost 89 per cent of its population compared to the period between 1907 and 2006. That suggests it has become critically endangered.
MacPhail, who was not involved in Soroye’s study, said this latest research reinforces what she and other bumblebee researchers have also found.
“The majority of our bumblebee species will drastically decline in population size and range, and some may even become extinct,” she said.
The idea that those declines are linked specifically to extreme heat adds a new piece of the puzzle, she said.
“The question is how we can help.”
MacPhail thinks the results will help identify areas to prioritize for bumblebee conservation, such as places where multiple species live or the edges of species’ ranges, where they’re under the most stress.
She agrees that what the bees need most is somewhere they can find refuge to withstand hotter temperatures, and that people can help by restoring and managing bee habitat. That may include making sure they have flowering plants to feed on from spring through fall that places where they nest or spend the winter are protected.
But MacPhail thinks efforts need to go beyond bee conservation too.
“We need to take these findings seriously and increase our actions to keep global warming to 1.5 C above pre-industrial levels,” she said.
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.
