Raw data from Behavioural regulation of mineral salt intake in honeybees: a self-selection approach

Minerals are required in small amounts to sustain metabolic activity in animals but mineral deficiencies can also lead to metabolic bottlenecks and mineral excesses can induce toxicity. For these reasons, we could reasonably expect that micronutrients are actively regulated around nutritional optima. Honeybees have co-evolved with flowering plants such that their main source of nutrients is acquired from floral pollen and nectar. Like other insects, honeybees balance their intake of multiple macronutrients during food consumption using a combination of pre- and post-ingestive mechanisms. How they regulate their intake of micronutrients using these mechanisms has rarely been studied. Using two-choice feeding assays, we tested whether caged and broodless young workers preferred solutions containing individual salts (NaCl, KCl, CaCl₂, MgCl₂) or metals (FeCl₃, CuCl₂, ZnCl_2, MnCl₂) in a concentration-dependent manner. We found that young workers could only self-select and optimize their dietary intake around specific concentrations of sodium, iron, and copper. Bees largely avoided high mineral solutions to minimize toxicity. These experiments demonstrate the limits of the regulation of intake of micronutrients in honeybees. This is the first study to compare this form of behaviour in one organism for eight different micronutrients.This article is part of the theme issue ‘From floral chemistry to landscapes: the natural processes influencing pollinator health’.