|Western yellowjacket at opening to paper nest|
|Bald-faced hornets guarding area around the nest. Click to|
see the three primitive ocelli eyes on top of their heads.
In the spring (late-April or May) young queens emerge from their overwintering sites that are often underground, or sometimes in logs or woody debris. Each queen begins her colony by starting a small paper nest in a tree, attic, or under a roof eve. She builds 20-50 hexagon-shaped cells under a small umbrella-shaped top. She’ll lay a fertilized egg in each cell, which grows into a legless grub and pupates into an unfertile female worker wasp in 2-3 weeks (the timing depends on weather and temperature).
As the female worker wasps emerge, they take over the tasks of enlarging the nest, foraging for food, feeding the young and the queen, and defending the colony. From here on, the founding queen will never leave her nest again.
|Female worker yellowjacket adding|
new paper layer to outside of nest
In late summer, the outnumbered larvae don’t produce enough nectar for all of the adult workers. So the foraging females’ food preference changes from insects to fruit -- or to scavenging human food, sodas, etc. This is when wasps (yellowjackets and hornets) tend show up as uninvited guests at your picnic, seeking sweet items like your iced tea or those watermelon slices (or Bud Light with lime, so I'm told).
In late summer or early fall, the aging queen begins laying unfertilized eggs that grow into fertile male “drones” and fertile females, neither of which have stingers. These “reproductives” remain in the nest and are fed by the workers until they’re ready to mate. Males fly off in search of distant, unrelated females.
Fertile females that successfully mate near their home nest will now rely on their fat reserves to overwinter as “new queens.” Each new queen might have mated with several males, storing the sperm in tight packets inside her abdomen where it remains dormant all winter. She’ll use it next spring to start the whole cycle anew.
|Cross-section of abandoned bald-faced hornet nest showing|
three egg cell layers, multiple nest layers, and nest opening