Bald-faced hornet varies depending on an individual's life cycle stage and geographic location. Adult hornets are carnivorous, and will prey upon several insect types. They have been observed consuming meat, spiders, fruit and insects. Adults will also drink flower nectar which they feed to their larvae. Female Bee Moths (Aphomia sociella) have been known to lay their eggs in Bald-faced hornet nests. The hatched larvae will then proceed to feed on the eggs, larvae, and pupae left unprotected by the wasp, sometimes destroying large parts of the nest as they tunnel throughout looking for food. Each spring, queens that were born and
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"