Non-honey bees

Have you ever seen a bee sitting on a flower or leaf with a droplet of liquid by its mouth? It looks as though the bee is blowing a bubble with bubble gum. What is it doing?

This behaviour is called ‘concentrating nectar’. Nectar is basically a sugar solution that can vary in concentration. When a bee evaporates water from the nectar, it becomes more concentrated. This benefits the bee because it can then carry more sugar (therefore, more calories!) in its crop. Concentrating nectar can also serve other purposes, such as thermoregulation — evaporating water cools the bee. This behaviour is widespread not only among bees, but can be seen also in flies.

You can read more about nectar concentrating in bees here: Portman, Z. M., Ascher, J. S., & Cariveau, D. P. (2021). Nectar concentrating behavior by bees (Hymenoptera: Anthophila). Apidologie, 52(6), 1169-1194.