CDFA Pest Prevention Plant Regulation Practice Exam

In which stage does the brown-tail moth overwinter?

1. Pupal Stage

2. Adult Stage

3. Egg Stage

4. Larval Stage

The correct answer is: Larval Stage

The brown-tail moth overwinter in the larval stage, specifically in the form of young caterpillars. During this period, the larvae find shelter in silk webs that they construct, allowing them to survive cold temperatures and adverse weather conditions while remaining dormant. This adaptation is crucial for their survival, as it ensures that they can continue their development when the weather warms up in the spring. In contrast, the other stages are not used for overwintering by the brown-tail moth. The pupal stage occurs after the larvae have fed and grown but is not a phase where the moths are active or feeding, making it unsuitable for overwintering. The adult stage, on the other hand, is more focused on reproduction and feeding, while eggs would typically not survive the harsh winter. Therefore, understanding the biology of the brown-tail moth highlights why the larval stage is essential for its overwintering strategy.