BEES get a buzz from caffeine, North East researchers have discovered.

It seems that honeybees get a boost from drinking flower nectar containing caffeine, which improves their memory.

Tests have shown that honeybees which fed on a sugar solution containing caffeine, which occurs naturally in the nectar of coffee plants and citrus flowers, were three times more likely to remember a flower’s scent than those feeding on just sugar.

Study leader Dr Geraldine Wright, a reader in neuroethology at Newcastle University, said that the effect of caffeine benefits both the honeybee and the plant.

“Remembering floral traits is difficult for bees to perform at a fast pace as they fly from flower to flower and we have found that caffeine helps the bee remember where the flowers are,” she said.

“In turn, bees that have fed on caffeine-laced nectar are laden with coffee pollen, and these bees search for other coffee plants to find more nectar, leading to better pollination.

“So, caffeine in nectar is likely to improve the bees’ foraging prowess while providing the plant with a more faithful pollinator.”

In the study, researchers found that the nectar of citrus and coffea species often contained low doses of caffeine.

They included robusta coffee species mainly used to produce freeze-dried coffee and arabica, used for espresso and filter coffee.

Grapefruit, lemons, pomelo and oranges were also sampled and all contained caffeine.

Caffeine is a defence chemical in plants and tastes bitter to many insects.

It occurs at a dose too low for the bees to taste but high enough to affect bee behaviour.

The effect of caffeine on the bees’ long-term memory was shown by the fact that three times as many bees remembered the floral scent 24 hours later and twice as many bees remembering the scent after three days.

Typically, the nectar in the flower of a coffee plant contains almost as much caffeine as a cup of instant coffee.

Just as black coffee has a strong bitter taste to us, high concentrations of caffeine are repellent to honeybees.

Dr Wright said: “This work helps us understand the basic mechanisms of how caffeine affects our brains.

“What we see in bees could explain why people prefer to drink coffee when studying.”

The project was part-funded by the Insect Pollinators Initiative which supports projects aimed at researching the causes and consequences of threats to insect pollinators.

Population declines among bees have serious consequences for natural ecosystems and agriculture since bees are essential pollinators for many crops and wild flowering species.

If declines are allowed to continue, there is a risk to our natural biodiversity and on some crop production.