A number of species of wasps in this family are native to North America, with the Black and Yellow Mud Dauber and the Blue Mud Dauber most often nesting on structures.
Mud daubers are solitary wasps that provide a nest and food for their larvae but do not further care for them. The nest is created from blobs of mud gathered by the female and formed into hollow cells, often with many cells arranged next to each other in columns. The female then gathers food, in the form of insect larvae or spiders, stings it to paralyze it, and then places this immobilized prey in the cell. She lays an egg in each cell, seals the cell with mud, and never returns. While the female mud daubers can sting it is a rare occurrence. They do not defend their nests and will sting only when they feel directly threatened. Nests are commonly placed in the eaves or attics of houses, but will often show up in other odd locations where the nest could be placed securely.
The most common mud daubers around structures are the large black and yellow species and the metallic blue species. These are long wasps with very long, thin waists and small abdomens. The black and yellow species may be an inch long, while the blue species is slightly smaller. The antennae are often somewhat curled.
Characteristics Important in Control:
Control can be accomplished by simply removing the mud nest. Otherwise, these wasps are highly beneficial due to the number of other insects and spiders they capture.