Abstract:
The honeybee nest parasite Aethina tumida (small hive beetle) uses
behavioural mimicry to induce trophallactic feeding from its honeybee
hosts. Small hive beetles are able to induce honeybee workers to
share the carbohydrate-rich contents of their crops, but it is not clear
whether the beetles are able to induce to workers to feed them the
protein-rich hypopharyngeal glandular secretions fed to the queen,
larvae and other nest mates. Protein is a limiting macronutrient in an
insect’s diet, essential for survival, growth and fecundity. Honeybees
obtain protein from pollen, which is consumed and digested by nurse
bees. They then distribute the protein to the rest of the colony in the
form of hypopharyngeal gland secretions. Using 14C-phenylalanine
as a qualitative marker for protein transfer, we show that small hive
beetles successfully induce worker bees to feed them the protein-rich
secretions of their hypopharyngeal glands during trophallaxis, and that
females are more successful than males in inducing the transfer of these
protein-rich secretions. Furthermore, behavioural observations
demonstrated that female beetles do not preferentially interact with a
specific age cohort of bees when soliciting food, but males tend to be
more discriminant and avoid the more aggressive and active older bees.
