The Heath Potter Wasp, Eumenes coarctatus, is a solitary wasp found on heathland areas near a stream, pond or other source of water. They are most frequently seen during summer and early autumn months.
After mating, the female wasp uses the water to prepare 25 or more small balls of mud, each one being separately carried to a chosen nesting site on a branch of gorse or heather. She then constructs a pot-shaped structure to be used as a nest and lays a single egg suspended by a silk thread from the inside edge of the completed pot. The female next searches for small moth larvae (caterpillars) which she paralyses with a sting before carrying them back to her nest. Over thirty larvae may be needed to fill the pot before she collects more mud to seal the entrance. After the egg hatches, the wasp larva takes about a week to finish its stored food. If the eggs are laid during early summer, the developed larva pupates, and an adult emerges in a few weeks; larvae emerging from eggs laid in autumn remain in the pots overwinter and only pupate the following spring. During the lifetime of an Eumenes female, she will prepare up to about twenty-five pots for her eggs.
