Bald-faced hornet is constructed too close to human habitation. They vigorously defend the nest, with workers stinging repeatedly, as is common among social bees and wasps. However, the baldfaced hornet has a unique defense in that it can squirt or spray venom from the stinger into the eyes of vertebrate nest intruders. The venom causes immediate watering of the eyes and temporary blindness. The life cycle of a colony can be divided into the founding stage, the ergonomic stage and the reproductive stage. Colonies show annual cycling. New nests are generally founded during spring and early summer by a single queen, though
Bald-faced hornet and colonies whose work force diminishes too early in the colony's life cycle will suffer a greater overall total loss in reproductives. A colony is divided into sterile males, female workers and the queen. All females are born with reproductive capacities. Caste systems are determined by larval feeding regime. G.T. Felippotti examined caste distribution amongst females in five small cell colonies and six large cell colonies. Small cell colonies had one queen and 17–21 female workers. Large cell colonies had 2–6 queens and 10–52 workers. Morphological comparisons revealed that queens are always larger than workers in the same colonies. Cuticular