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14 July 2017

Bees under Threat from the Warming Climate

It’s been common knowledge for a while now that the bee population is dwindling and new research from the University of Würzburg’s Department of Animal Ecology and Tropical Biology shows that things aren’t going to be getting better for them any time soon.

When it comes to solitary bees – those that don’t live in large hives – there is a lot of pressure to build nests and provide for offspring during the few weeks that they’re alive. Survival is dependent on the presence of pollen, meaning they have to time their hatching correctly so that there are plants available for them to feed from.

Unfortunately, as a result of climate change steadily warming the planet, the risk of temporal mismatches between bee and plant species has increased. This essentially means that there is a greater likelihood of bees hatching before their food source has flowered.

The research team at the University of Würzburg collected three species of mason bee – all of which emerge in the spring – to investigate how an early emergence could impact them. They created a controlled environment in a series of cages which allowed them to influence whether the bees hatched with the flowering of plants, or three and six days beforehand. Their findings displayed concerning repercussions for those that emerged early.

A large portion of the bees who hatched three or six days before the plants had flowered didn’t survive, while those that did displayed less productivity and lower reproductive output. To try and adapt to the lack of available pollen, the bees attempted various behavioural strategies, including producing fewer female offspring and increasing their activity in the second half of their lives. All of these had negative impacts on the species as a whole though by causing a decline in population or putting the brood at risk from predators and parasites.

“Already a minor temporal mismatch of three or six days is enough to harm the bees,” Mariela Schenk who authored the study said. “Although we found that the bee species we investigated developed species-specific strategies to mitigate the impact of temporal mismatches, the insects still suffered severe fitness loss.”

If the warming climate is already causing problems for solitary bees then the future does not look hopeful. Their inability to effectively adapt to temporal mismatches means that even if they survive, the species is still going to struggle, and this will have a knock-on effect on plant pollination.

James Darvill

James is a passionate scriptwriter and reluctant poet with a talent for the dystopian. When he’s not staying up late watching the Simpsons he’s beating the world at Mario Kart, always with a glass of wine in hand.