Common yellow face bee using Dufour’s gland secretions to seal nest entrance

Common yellow face female (Hyaleus communis) bee using Dufour’s gland secretions when sealing her nest entrance

What is Dufour’s gland? Well according to Mitra, it’s a gland, although it and the poison gland are associated with the sting, its actual function is to secrete chemicals that could be used in nest building, larval food, various communicative functions such as host marking, kin and nestmate recognition, sex and trail pheromone as well as fertility signalling. So it depends upon the species that are using it and for what function. For more details see Function of the Dufour’s Gland in solitary and social Hymenoptera. (Aniruddha Mitra) 

Dufour’s Gland has many different functions

I was fascinated by this female. I had seen several and filmed several making their nests from a cellophane-like membrane as opposed to other cavity-nesting solitary bees that use materials which they find nearby their nest sites, such as mud for Red mason bees or pieces of a leaf which the female leafcutter bee cuts and utilises in her nest. This female occasionally dabs the Dufour’s gland when making the nest lining. Cane shows the chemical composition here.

However, after completing the seal over the nest as per the nest inners, the use of the Dufour’s Gland was much more common and regular on the outside of the nest entrance. Perhaps some form of protection as against certain pests? It certainly did not work with the Gasteruption jaculators that attacked several of my yellow face bee nests, the subject of a film to be edited soon.

With thanks to Aniruddha Mitra for his permission in using the diagram above, from the research paper above.