Bald Faced Hornet NestDissection

This dissection was performed AFTER the wasps had died off from repeated frosts in mid-November, 2006. Do not approach a

wasp nest until the wasps die off, because they are extremely aggressive. Sometimes, the killing of one wasp can set off a

pheromone trail telling the hive to swarm. That would end up being a very painful experience for everyone involved.

This nest was hanging from a limb in our back yard. Even though they are called “hornets”, they are in the vespid wasp family and were so aggressive that we had to avoid a portion of the backyard until the inhabitants died off from repeated frosts in November.

The back side of the nest after removing the outer layers of “paper”. Bald faced hornets chew bits of tree bark, and mix it with their saliva to form a thin paper-like material which they glue together, layer upon layer, to form the hive.

Pictured here are the combs and cells of the hornet nest. Each comb contains many hexagonal cells into which the queen lays an egg. The eggs hatch into larvae which spin silk cocoons that cover the cells. The larvae eventually turn into pupae.

The cells with white silk once held pupae that matured into adults and left the nest.

This is a new pupa just beginning its development within its cocoon. I pulled the silk of the cocoon away to reveal the pupa.

These pupae would have matured into adults if the weather had stayed warmer for a bit longer. You can see the beginning formation of eyes and mouthparts.

This is a closed cell with a hornet inside. The cells are made of a cellulose-based material capped with silk.

I pulled the silk cap off the cell to reveal the developing hornet.

This is the ventral view of the developing hornet. Note how it is all curled up. The antennae are folded down over the face, and the wings are folded down over the body.

Lateral view of a fully developed hornet. This one was much further along in development over the previous photo.

Ventral view of a fully developed hornet. Note the development of the mouthparts.

Note the white face which gives these hornets their name. I’ve always enjoyed photographing these hornets as they really are beautiful to behold, although I move very slowly when getting up close for photos of active hornets.

Dorsal view of the mature hornet. The bald faced hornets are closely related to yellow jackets. Although, most yellow jackets nest underground or at ground level, whereas bald faced hornets nest in trees.

THEEND

Bowdoin, MaineNovember, 2006

All photos were taken by Laurie Haines, and are the copyrighted property of Laurie Haines.