Wasps

Wasps are social insects that live in colonies with many thousands of members. Wasps construct their nests in many different locations, e.g. the ground, trees, or in cavities such as eaves, attics, garden sheds, etc… They feed on sweets and proteins and commonly invade outdoor activities. Wasps become most aggressive in autumn when the colony begins to die out except for the queen wasp.

Wasp Lifecycle in Ireland

Understanding the wasp lifecycle explains why wasp problems in Ireland follow a predictable seasonal pattern:

• February–April: Queen wasps emerge from hibernation and begin building a new nest alone. Nests are small (golf ball size) and queens are rarely aggressive at this stage.
• May–July: Worker wasps hatch and the colony grows rapidly. By July a typical Irish garden wasp nest contains 3,000–5,000 workers.
• August: Peak nest size — up to 10,000 workers in a large nest. Most wasp callouts in Ireland occur during August.
• September–October: The colony begins to die off. Workers are no longer feeding larvae and stop receiving the larval secretions that suppress their aggression. This is when wasps become most aggressive and are drawn to sweet foods and drinks outdoors. The queen produces new queens and males who leave to mate.
• November onwards: All workers and old queen die. New queens overwinter in sheltered spots. The nest is never reused the following year.

This lifecycle explains why wasp problems get worse in late summer — the workers become agitated as their food source disappears and the colony dies around them. Professional treatment is most effective when the nest is still active and workers are present to carry the insecticide back through the nest.