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 acts as a selective pressure on the workers, so they are more likely to exercise reproductive restraint. It has been suggested that workers in reproductive nests may kill their queen so they can reproduce. When researchers at the University of Sheffield examined a collection of nineteen "D. maculata" nests during the reproductive phase of their life cycle, they found that 14/19 nests did not have a queen. Matricide might occur after sufficient workers have been raised and queen-destined eggs have been laid. However, matricide has not been directly observed and other causes of death are possible. Diet in "D. maculata"