This week while going through some items in a storage shed, I came across a beautiful dried ball of mud inside an antique trunk. It was the nest of a wasp known as a mud dauber.
When we think of wasp nests, usually the first thing that comes to mind is the papery nest of the paper wasp or the football-shaped nest of hornets. Mud daubers build their nests out of mud. There is plenty of mud for the wasps this summer because of the regular rains we’ve been having.
Mud daubers are not social insects like paper wasps and the others. Instead, they spend their lives as single, solitary insects. They do everything by themselves including, building a nest, laying eggs and collecting food for their young.
There are many different species of mud daubers in Michigan, this one is called the “black and yellow mud dauber”.
The adults look similar to the more common social wasps but are larger and have exaggerated features like the thread-like connection between their abdomen and thorax.
The female mud dauber builds the nest by collecting mud along the edge of puddles. Using her mouth parts, she rolls the mud into a ball then lifts it into the air and carries it to the nesting site. There she adds the mud to her nest, building rooms or cells for her young. Each cell is big enough for one young mud dauber.
Here she is, busy plastering new mud on her nest.
The entrance to the nest is open, she must be nearby.
While the female is away from the nest gathering mud or foraging for food, she temporarily closes the entrance to her nest to keep predators away from her young. During that time, the daubers are in the larval stage of their life cycle.
The female also packs away food for the developing larvae by placing insects or spiders into each cell so the larva has enough food in its cell to carry it through its growing stage. Some types of mud daubers only prey on spiders while others prefer caterpillars or other insects.
The entrance to the nest is closed shut. Mama mud dauber must be out collecting more mud or insects for her young.
The prey is only for the young though. The adults feed on nectar, honeydew from aphids or other sugary liquids. Sometimes you can spot them sipping sugar water from hummingbird feeders.
Unlike other wasps and hornets, mud daubers don’t defend their nests. They are not aggressive and rarely sting. Although if you try hard enough you can sometimes provoke one into stinging you.
According to one university website, some species “sing” while building their nest! Mine didn’t seem to be in a singing mood when I found her.
They are generally considered beneficial insects because they eat other insects. You could argue that the spider-eaters are not very beneficial because spiders eat insects too — that is unless you hate spiders.
Most of the time we don’t notice the daubers until they build a nest somewhere where we don’t want it. Some people destroy the nest as soon as they find them.
There seems to be a small industry built around exterminating mud daubers and getting rid of their nests. I prefer to let leave them alone and let them go about their business.
I’ve noticed other smaller species of mud dauber wasp around too. They are not shy and can be very annoying as they buzz around looking for small holes to use for building their nests.