Which type of wasps do not defend their nests?

Mason wasps are a type of solitary wasp that do not defend their nests. Unlike social wasps, which live in colonies and exhibit defensive behaviors to protect their nests, mason wasps operate independently. They typically nest in small cavities or create mud nests and do not have the complex social structures that encourage nest defense. This solitary behavior means that even when disturbed, mason wasps are less likely to react aggressively compared to social wasps or hornets, which will swarm and defend their nests vigorously against perceived threats.

In contrast, social wasps, hornets, and yellow jackets are all species that will aggressively protect their nests. These types of wasps live in communal colonies and engage in social behaviors that include defending their territory and young. This defense mechanism is crucial for their survival and reproductive success, making them more likely to attack if their nest is threatened.