Bald-faced Hornets

Bald-Faced Hornets

Identification

• Scientific Name: Dolichovespula maculata
• Appearance: Bald-faced hornets are large black and white wasps. They are primarily black with distinctive white markings on their face, thorax, and at the tip of their abdomen.
• Size: Adults range from 0.5 to 0.8 inches (12-20 mm) in length.

Habitat

• Location: Found throughout North America, particularly in wooded areas, parks, and residential settings.
• Nest Location: Bald-faced hornets build paper-like nests from chewed wood mixed with saliva. These nests are typically found:
  • Hanging from trees or shrubs
  • Attached to building eaves, utility poles, or other structures
  • High off the ground for safety from predators

Nest Characteristics

• Nests are large and oval-shaped, with a grayish, papery exterior.
• They can grow to the size of a basketball or larger by late summer.
• Entry is through a single hole near the bottom.

Behavior

• Social Structure: Bald-faced hornets are social insects, living in colonies of 100 to 400 workers.
• Aggressiveness: They are highly defensive and will aggressively protect their nest.
• Stinging: They can sting multiple times without losing their stinger. Their sting is painful and delivers venom that may cause localized swelling and itching.

Diet

• Bald-faced hornets are primarily carnivorous, feeding on:
  • Flies, caterpillars, and other small insects (which they chew into a paste to feed their larvae)
  • Adult hornets may also consume nectar and fruit juices.

Life Cycle

1. Spring:
   • A fertilized queen emerges from hibernation and begins building a nest.
   • She lays eggs and cares for the first batch of larvae.
2. Summer:
   • The first workers emerge and take over nest expansion and foraging.
   • The queen focuses solely on egg-laying.
3. Late Summer/Fall:
   • The colony reaches its peak size.
   • New queens and males are produced for mating.
4. Winter:
   • The colony dies out, leaving only fertilized queens to hibernate.

Predators

• Birds, praying mantises, and spiders may occasionally prey on bald-faced hornets.
• Raccoons and bears may attempt to raid their nests for larvae, though the hornets' stings provide strong defense.

Benefits

• Bald-faced hornets are beneficial in controlling pest populations by preying on nuisance insects.
• They also contribute to pollination while foraging for nectar.

Risks

• Their aggressive nature poses a threat to humans and pets if the nest is disturbed.
• Their sting can cause severe allergic reactions in sensitive individuals.

Control and Prevention

• Prevention: Inspect outdoor areas regularly for nests, particularly in spring and early summer when nests are small.
• Professional Removal: Due to their aggressiveness, it is recommended to have nests removed by a licensed pest control professional.
• DIY Precautions:
  • If removal is attempted, it should be done at night when the hornets are less active.
  • Use proper protective clothing and a specialized wasp spray.
  • Never stand directly below the nest during treatment.

Similar Pests: Yellow Jacket Wasps, Carpenter Bees