Mud dauber (sometimes "dirt dauber," "dirt dobber," or "dirt diver" in the southern U.S.) is a name commonly applied to a number of wasps from either the family Sphecidae or Crabronidae that build their nests from mud. Mud dauber may refer to:
Mud daubers are long, slender wasps, the latter two species above with thread-like waists. The name of this wasp group comes from the nests that are made by the females, which consist of mud molded into place by the wasp's mandibles. There are three common species of mud daubers, each with distinctive coloring: the organ-pipe mud dauber (solid black coloring), the black and yellow mud dauber, and a stunning metallic-blue mud dauber with blue wings.
The black and yellow mud dauber's nest is composed of a series of cylindrical cells that are plastered over to form a smooth nest about the size of a lemon.
The metallic-blue mud dauber foregoes building a nest altogether and simply uses the abandoned nests of the other two species and preys primarily on black widow spiders..
Mud daubers are rarely aggressive.
Mud daubers pose a special risk to aircraft operation, as they are prone to nest in the small openings and tubes that compose aircraft pitot-static systems. Their presence in these systems can disable or impair the function of the airspeed indicator, the altimeter, and/or the vertical speed indicator. It is thought that mud dauber wasps were ultimately responsible for the crash of Birgenair Flight 301.