Bald-Faced Hornet

Category:

Actual Size: 12 to 15 mm

Characteristics: Black with a white pattern on the face.

Legs: 6

Antennae: Yes

Habitat: Live in paper nests that are at least three feet off the ground, often in trees or on the sides of buildings.

Habits:

  • Typically appears in the late summer months.
  • Lives in colonies that may have between 100 to 400 members.
  • Known to be a more aggressive stinging insect and will sting when provoked.

Bald-Faced Hornets in The North Bay and East Bay of California

The bald-faced hornet is actually a wasp and a relative of the yellowjacket. They get their name from the ivory-colored markings on their face. Bald-faced hornets are relatively large flying insects and will defend their nests aggressively when they feel there is a threat. These beneficial wasps live in colonies with thousands of individuals and would be a lesser threat to humans if they did not nest in structural voids, attics, and cavities associated with landscaping features. Worker bald-faced hornets are very active outside their nests in the daytime during the summertime, which is when they’re most often encountered by residents in the Bay Area.

Bald-Faced Hornet Habitat

The bald-faced hornet often builds its nests in residential areas. Their nests are often built high off the ground. These hornets build gray-colored, egg-shaped nests that can become quite large, some growing to 24 inches in length and 30 inches in diameter. Nests are created in spring and early summer by worker hornets chewing on natural wood fibers. Bald-faced hornets will construct nests in trees, under eaves, around light structures on buildings, and inside children’s playhouses. Their nests are often the shape of a football. At the top of the nest, there are heat vents to allow heat to escape the nest.

Bald-Faced Hornet Behavior, Threats or Dangers

Like other social wasps, bald-faced hornets are capable of stinging repeatedly. Bald-faced hornet stings are venomous and can cause pain and swelling for about 24 hours. People who are allergic to bee stings may have similar reactions to a bald-faced hornet sting.

Bald-faced hornets scavenge in trash receptacles and forage upon food and beverages consumed outdoors. They also consume ripe fruit in gardens, farms, and vineyards. In the autumn, the combination of cooler temperatures and reduced food stimulates newly emerged reproductive wasps to seek warm shelter, and they are more likely to invade homes. Whether you notice a bald-faced hornet forming on the side of your property or these insects inside your property, it’s important to always enlist the help of a licensed wasp control expert.