IMAGE: A female squash bee in a squash flower view more
Credit: Dr. Nigel Raine/ University of Guelph
An insecticide used to control pest infestations on squash and pumpkins significantly hinders the reproduction of ground-nesting bees — valuable pollinators for many food crops, a new University of Guelph study has revealed.
This first-ever study of pesticide impacts on a ground-nesting bee in a real-world context found female hoary squash bees exposed to imidacloprid dug 85 per cent fewer nests, collected less pollen from crop flowers and produced 89 per cent fewer offspring than unexposed bees.
“Because they’re not making nests and not collecting pollen, they cannot raise offspring,” said Dr. Susan Willis Chan, a post-doc in the School of Environmental Sciences (SES), who conducted the study with Dr. Nigel Raine, holder of the Rebanks Family Chair in Pollinator Conservation in SES. “That means imidacloprid-exposed populations are going to decline.”
Neonicotinoids (or neonics) are neurotoxic insecticides that kill insects by attacking their nervous systems, affecting learning, foraging and navigation in many kinds of bees. Farmers use the neonic imidacloprid to control cucumber beetles, the most damaging crop pest for squash and pumpkins.
Many species of ground-nesting bees, including the hoary squash bee, are responsible for pollination of numerous fruits, vegetables and oilseed crops in North America, said Chan.
“Solitary ground-nesting bees make up about 70 per cent of bee species. It’s a really important ecological group and is also really important in crop pollination,” she said.
However, these ground-dwellers are often overlooked when it comes to evaluating the impacts of pesticides on pollinators, she added.
Published recently in Scientific Reports , the study involved three years of monitoring the foraging and nesting behaviour of squash bees.
To mimic field conditions, Chan held the bees in mesh-covered enclosures that still allowed exposure to sun and rain and other environmental factors. She applied pesticides in ways that mirror actual use in farmers’ fields.
Chan tested three insecticide treatments: the neonic imidacloprid applied to soil at planting time; the neonic thiamethoxam applied as a seed treatment; and an anthranilic diamide (an emerging non-neonic insecticide) sprayed onto growing plants. A fourth group without insecticides served as a control.
Studying the bees for three years allowed the team to show longer-term impacts of imidacloprid exposure on reduced nest-building, foraging and offspring reduction.
Bees visiting squash plants treated with anthranilic diamide collected significantly less pollen than those in the control group but had no fewer nests or offspring. Chan saw no measurable effects from the thiamethoxam seed treatment on pollen harvesting, nest construction or offspring production.
“Farmers and regulators need to look at alternatives to applying imidacloprid to soil for controlling pests on squash and pumpkins,” she said.
“My recommendation to pumpkin and squash farmers is to stay away from imidacloprid applied to soil to keep their squash bees healthy.”
Raine said it’s likely other solitary, ground-nesting species are also being affected.
Noting that other ground-nesters live in farm fields, he said, “The sort of impacts from soil-applied pesticide exposure we’ve seen in this study could affect many other species of wild bees.”
He said current regulatory assessments for insect pollinators fail to consider risks associated with soil pesticide residues. “Our results highlight why this should be changed to better characterize risk for the many bee species that spend a large proportion of their life in soil.”
Given the importance of pollinating insects to crop production, Chan said, “Farmers need to protect their crops from pests, but they also absolutely need to protect pollinators from the unintended effects of pesticides.”
Referring to imidacloprid, she said, “The data on this particular product are so clear that there’s really no question about what has to happen. We have to find something else.”
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This research was funded by the Ontario Ministry of Agriculture, Food and Rural Affairs; the Ontario Ministry of the Environment, Conservation and Parks; the Ontario Fresh Vegetable Growers’ Association; the Natural Sciences and Engineering Research Council; and the Weston Family Foundation.
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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.
