Invertebrates
Mud Dauber
Sceliphron and relatives · also called mud daubers, dirt dauber
A row of tube-shaped mud cells clings to the underside of a porch eave, each one built alone by a female mud dauber and stocked with paralyzed spiders, sometimes including a black widow, sealed inside as living food for a single hidden larva.
Overview
The mud dauber, genus Sceliphron and relatives, is a solitary, spider-hunting wasp found in grassland and forest habitat across most of the world. Its distinctive mud-tube nests, habit of provisioning larvae with paralyzed spiders including dangerously venomous species, and notably docile temperament make it one of the more genuinely beneficial stinging insects most people encounter.
A solitary hunter with a spider-stocked pantry
Without a colony to defend, the mud dauber has little reason to sting, instead spending its energy hunting and paralyzing spiders, one careful nest cell at a time, to provision offspring it will never actually meet.
Status
Least Concern — widespread and common across suitable grassland and forest habitat throughout its range.
Mud Dauber: common questions
Does the mud dauber actually hunt black widow spiders?
Yes, before sealing each mud nest cell, a female mud dauber stocks it with several paralyzed spiders as living food for her larva, and species as dangerous as black widows are among the spiders regularly targeted, making the mud dauber a genuinely useful natural check on venomous spider populations.
Is a mud dauber dangerous to people?
Not really — the mud dauber is generally docile and reluctant to sting since it has no colony worth defending, unlike social wasps such as yellow jackets, and most stings only occur if one is directly grabbed or trapped against bare skin.
How does a mud dauber build its nest?
A female mud dauber constructs a nest of individual mud tubes or cells entirely on her own, often attaching them to walls, eaves, or other sheltered structures, and stocks and seals each cell separately after laying a single egg inside alongside paralyzed spider prey.
What's the difference between a mud dauber and a social wasp like a yellow jacket?
A mud dauber lives and works entirely alone with no colony, workers, or shared nest to defend, unlike social wasps such as yellow jackets that live in large cooperative colonies, and this solitary lifestyle is a major reason the mud dauber is considerably less likely to sting defensively.