Grand design

Downsizing a bit from Kevin McCloud’s usual offering, this Common Mud-dauber (Sceliphron laetum) nest is nonetheless an impressive build. Working alone on a minimal budget with no advice from architects, the mud-dauber completes its structure in just a few days.
 
Shaunna and Chris from Strath Creek sent us a photo of a “waspy-thingy” and several nests on a steel locker in their car-port. As it happened we were already following the progress of a similar mud-dauber wasp as it constructed a nest on the brick wall of our house.
 
 
 
The Common Mud-dauber nest consists of a number of parallel tubular cells constructed of mud by the female who emits a high-pitched buzz as she builds. On completion of each open-ended cell, the mud-dauber lays an egg, then goes in search of a spider, which it paralyses with its sting, carries to the nest and forces into the open cell to provide food for its larva when it hatches. The cell is then sealed and eventually the whole nest is padded out and smoothed over with mud, and finally an array of randomly oriented ridges as decoration/disguise/reinforcement (who knows ?) completes the structure (see picture above).
 
To make life more difficult for the mud-dauber, there is often the threat of a Cuckoo Wasp (Stilbum cyanurum) female laying its eggs in the mud-dauber’s nest while it is away collecting spiders. The cuckoo wasp larva feeds on the mud-dauber’s larva and/or on its spider food supply.
 
The pictures below include the gradual construction of the mud-dauber’s nest.

Some fascinating details about the mud-dauber can be found on the WA Museum’s website, including a comparison with one of the similar looking potter wasps of the genus Delta, which is actually in an entirely different family (Vespidae) compared to the mud-dauber which belongs to the family Sphecidae. Potter wasps build a different shaped mud nest and stock it with caterpillars rather than spiders. The Orange Potter Wasp was featured in a previous FoF post.