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Mud Daubers

Female Black and Yellow Mud Dauber Wasps Making Cells & Laying Eggs

8-19-16  mud dauber 028If you look closely at the ground directly in front of this female Black and Yellow Mud Dauber wasp you will see the clump of mud that she has collected and rolled into a ball with her mandibles.  This lump of mud will be carried back to the nest site in the wasp’s mandibles, and then used as building material to mold a cell.  After making the mud cell, the wasp then goes and locates spiders, stings them (paralyzing but not killing them) and brings them back to the cell, into which she packs them.  When the cell is sufficiently stuffed with spiders, she lays an egg and seals the cell with more mud.  She makes and fills several of these cells and typically covers all of them together with a final layer of mud.  When the wasp egg in each cell hatches, the larva has living spiders to eat that haven’t decomposed, due to the fact that they are not dead. Eventually the larval wasp pupates and the adult wasp chews its way out of the cell.

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Black and Yellow Mud Daubers Collecting Mud & Building Cells

7-20-15 mud dauber 140There are many species of mud daubers — wasps that build mud cells in which they lay eggs and in which their larvae develop. The female Black and Yellow Mud Dauber gathers mud at the edge of a pond or puddle, rolls it into a ball, grasps it in her mandibles and flies it back to her nest site, a spot protected from rain, often on a man-made building. Here she constructs several mud cylindrical cells.

Like most wasps, mud daubers are predators, and they provision their mud cells with select spiders (including jumping spiders, crab spiders and orb weavers) which they locate, sting and paralyze before stuffing them into a cell. The female lays an egg amongst the spiders, so that when the egg hatches the emerging larva will have a supply of spiders (that haven’t decomposed, because they’re not dead) to eat. She seals the cell with mud, and repeats this process several times after which she covers the small group of cells with more mud. The Black and Yellow Mud Dauber larvae pupate in the fall, overwinter inside the cells and emerge as adult wasps the following spring.

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