Flowers with caffeine-laced nectar use the highly-addictive substance to keep bees coming back for more, a study in Current Biology reports.
This addiction is very similar to the way humans can become hooked on caffeine. However, when bees consume caffeine it can lead to problems for the colony as a whole. This is because, though the bees are still getting nectar, the caffeine causes the insects to forage at a much less optimal rate than they normally would.
The study was inspired by earlier research, which found that bees exposed to caffeine could learn new flowers more quickly and remember them for longer periods of time. Based on those findings, it seems that such a practice would make bees into much better pollinators. However, that is not the case.
Rather, while the bees forages more often when on caffeine, they check the caffeinated flowers at an almost obsessive rate. This causes them to ignore other, nutritious flowers. In addition, they also did four times the usual number of dances to alert the rest of the colony to the flower’s presence, The Washington Post reports
“The effect of caffeine is akin to drugging, where the honey bees are tricked into valuing the forage as a higher quality than it really is,” said Roger Schürch of the University of Sussex and the University of Bern, in a statement. “The duped pollinators forage and recruit accordingly.”
The study showed that the effect of this “drugging” often lasted for days at a time. Furthermore, bees who had experienced it would come back to the caffeinated nectar time and time again. On the other hand, bees that had not been exposed to caffeine would check their previous flowers and then move on to look for food in other places.
Caffeine is commonly found in the nectar of both coffee and citrus plants. Plants take advantage of the substance’s bitter taste, which is used to ward off herbivores. That bitter taste is also in the nectar to make sure the bees move quickly from flower to flower. But the substance is actually drugging the insects instead.
While the addiction to caffeine is not harmful on its own, it does bring down colony production. The constant checking of caffeinated flowers causes the bees to not take advantage of other natural food sources, which can lead to bigger problems down the line