How a dry spring may be affecting B.C.’s bees

Much of B.C. experienced a drier than normal spring this year, conditions that researchers and honey producers say can be harmful to pollinators.

Already this season, bee enthusiast and gardener Elaine Sedgman says she has noticed a reduction in the number of native bees buzzing around her flowers in Kamloops. 

She volunteers with the Native Bee Society of B.C. and collects and records when and where she spots native bee species, for research. 

Across North America, wild bee populations are in decline, and one of the contributing factors is climate-related events like droughts, which stress the plants that pollinators rely on.

That’s been a worry for the nearly 500 bee species estimated to live in B.C. as the province has seen consecutive years of droughts and heat waves, most notably the 2021 heat dome.

According to the B.C. Drought Information Portal, 27 per cent of the province was experiencing some level of drought as of the end of June — an improvement from 40 per cent in May.

Dry soil makes for difficult digging

Behavioural ecologist Caleb Bryan says bees in B.C. can be particularly vulnerable to droughts because most of them are ground nesters.

“Drought dries and hardens soils and vegetation, making nest excavation and maintenance more difficult,” said Bryan, a researcher at the Connecticut Agricultural Experiment Station who has worked extensively with Canadian bees.

He added that drought can also reduce leafy shade for nesting bees.

“Over time, these changes make it harder for bee populations to persist across seasons,” he said.

Stressed flowers don’t taste so sweet

Another challenge, Bryan said, are flower changes.

“Drought-stressed plants often produce less nectar, and the nectar they do produce can differ in sugar ratios and concentration,” said Bryan.

He said the quantity and quality of both nectar and pollen can be impacted, reducing food supply for bees and potentially hindering their growth.

Drought stress can also impact the signals that plants send to bees.

Under periods of water stress, flowers may change colours and their scents can weaken. Some plants even alter the thermal patterns of their petals, which are invisible to the human eye.

“Drought makes flowers harder for bees to locate and less attractive and rewarding once they do,” Bryan said. 

Honey production also at risk

Emily Huxter, owner of Wild Antho bee farm in the North Okanagan, says when there is a change in nectar quality or amount due to plant stress, there is typically also a reduction in honey production.

“We are all sitting on the edge of our seat wondering what’s going to happen this year,” she said.

Her farm expects to know the impact of this spring’s drought in a few weeks, when the honey flow is set to begin. 

People can help out, according to Bryan, by planting a variety of native plant species that bloom throughout the spring, summer and fall. He said having an abundance of flowers is particularly important in areas where honey bees are also foraging, so there is enough food to go around for both them and native bees.