When it comes to flowers, bees and other bumblebees seem to take an important notion into account: energy efficiency. Each species – depending on its own characteristics – would therefore have its favorite flowers. Thus, the more varied the available flowers, the more the different species of foraging insects find their account.
What is energy efficiency?
Francis Ratnieks is Professor of Beekeeping at the University of Sussex (UK). Co-author of a study published in the journal Ecology on January 19, 2021, the interested party looked at the concept of energy efficiency in bees and other foraging insects. However, the latter would ensure that each species has its favorite flowers. This is about a “foraging benefit” derived from the energy efficiency of the insect itself. It is the ratio between the energy required to fly to a flower – determined by the weight of the insect – and the energy obtained from the nectar of the flower correlated with the speed of the insect. In other words, it is the report indicating the energy expended by the insect to draw energy from flowers.
Francis Ratnieks and his team timed the speed of more than a thousand bees and drones. The goal? Estimate how many flowers these insects can collect in one minute. In addition, this data was related to the weight of the insects, the latter measured using a suitable balance. According to the study leaders, bumblebees are twice as impressive than bees, but also twice as fast.
The importance of maintaining flower diversity
According to the results, the insects are on a “tightrope of energy”. This means that during collection, these spend about half the energy that they get nectar from flowers. In addition, these differences in energy efficiency explain, for example, why bumblebees have a foraging advantage – for certain flowers – over honey bees. These are faster when it comes to visiting the flowers, can collect more nectar, but are on the other hand heavier and spend more energy to fuel their foraging. In addition, some flowers have more or less adapted morphologies to the insects mentioned.
Thus, the diversity of flowers is a very important element for the preservation of bee and bumblebee species. In addition, these insects contribute to the sustainability of 75% of crops. For Francis Ratnieks, maintaining flower diversity must be a priority in the conservation of foraging insects.