- Lifespan
- 4–6 weeks as adults
- Size & Weight
- Wingspan 78–102 mm; body length approximately 40–50 mm
- Habitat
- Deciduous and mixed woodlands, gardens, parks, and orchards with willow and apple trees present.
- UK Distribution
- Found throughout England, Wales, and southern Scotland; more common in southern regions. Single-brooded, resident species; adults emerge in May–June.
- Diet
- Larvae feed exclusively on willow and aspen leaves; adults do not feed and have reduced mouthparts.
- Predators
- Birds (particularly shrikes and cuckoos), spiders, and parasitic wasps and flies targeting larvae.
- Mating Season
- May to July
- Breeding
- Females lay 1–4 eggs singly or in small groups on host plant leaves. Larvae develop over 4–5 weeks; pupation occurs in soil or loose bark, overwinting as pupae.
- Behaviour
- Nocturnal and attracted to light. When threatened, the moth retracts its forewings to reveal distinctive eyespots on the hind wings, a defensive display that startles predators. Adults rest during the day with wings tent-like over their bodies.