Monthly Science: Organ Pipe Mud Dauber Wasp Nest Disassembly

The empty Organ Pipe Mud Dauber Wasp nest popped off the wall with relatively little damage:

Organ Pipe Wasp Nest - overview
Organ Pipe Wasp Nest – overview

The open cells on the back side show the wasps don’t waste any effort on putting mud where it’s not needed:

Organ Pipe Wasp Nest - wall side
Organ Pipe Wasp Nest – wall side

Cracking it in half shows the rugged walls between the cell columns:

Organ Pipe Wasp Nest - cross section
Organ Pipe Wasp Nest – cross section

Several cells contained three or four (thoroughly dead!) spiders apiece, evidently the result of un-hatched eggs:

Organ Pipe Wasp Nest - failed egg - spiders
Organ Pipe Wasp Nest – failed egg – spiders

Each successful cell contained a brittle capsule wrapped in a thin cocoon, surrounded by fragments of what used to be spiders, with an exit hole chewed in the side:

Organ Pipe Wasp Nest - capsule detail
Organ Pipe Wasp Nest – capsule detail

I regret not weighing the whole affair, as all that mud represents an astonishing amount of heavy hauling and careful work by one or two little wasps!