Mud Dauber Wasp – Sceliphron caementarium

Mud Dauber Wasp – Sceliphron caementarium
Order Hymenoptera – Ants, Bees, Wasps and Sawflies
Live adult mud dauber wasps and nest photographed at Illinois and Pennsylvania. 

This active founding female is in-process building a mud nest – she takes 2-3 minutes to return with a glob of mud.

Black-and-yellow mud daubers are solitary wasps about 1 inch long. A lone founding female builds a nest in a location protected from rain. She carries small globs of liquid mud into location and then uses a furious buzzing of her wings to shape the mud and drive out air bubbles, just like workers use vibrating equipment when laying thick layers of concrete. When the mud dries sufficiently, the wasp provisions each cell with live, paralyzed spiders and a single egg is laid in each cell. She then seals and abandons the nest. The eggs hatch, and the larvae feed on their fresh food stores, growing up to one inch long. Larvae then spin cocoons and pupate within the cell.

The variety of spiders captured by these wasps is amazing. One nest polled by Brad Barnd,, contained more than 25 spiders from several different families, including orb weavers, crab spiders, running crab spiders, jumping spiders, and ghost spiders: Mud Dauber prey revealed. Although mud daubers are capable of stinging (that's how they paralyze the spiders), they are not aggressive and do not defend their nests as do honeybees, paper wasps, or yellowjackets.

mud dauber wasp lateral view
The female mud dauber is eating pollen to fuel her nest-building and hunting and egg-laying. They feed at hummingbird feeders too.

Mud dauber dorsal view

Order Hymenoptera: Bees, Wasps, & Ants

Hymenoptera (Latin for membrane wing) is a vast assemblage of insects second only to Coleoptera (beetles) in the number of described species. Hymenoptera number some 115,000 species – of which 18,000 live in North America. Hymenopterans inhabit a wide variety of habitats, and show an incredible diversity in size, behavior, structure and color.
Insects & Spiders | Bees & Wasps Index | Bees & Wasps