To feed their families, the mud daubers (dirt daubers) pack their dinners on my back porch. Spiders seem especially tasty to them, so they paralyze the main course and stuff them into their custom designed nursery units.
Mud daubers are members of the wasp family and are not hostile "stingers" as are some of their cousins. However, they are aggressive in another area: nursery construction and stocking of provisions. In the summer, the female frequents the edges of a mud puddle where she rolls wet dirt into tiny balls about the size of a BB. Then, she flies one uniform ball at a time, held in her mandibles (jaws), to her construction site. Pellet by pellet she constructs tubes shaped like organ pipes. The females in South Texas seem partial to the mortar indentations on my bricked back porch. Bit by bit, BB by BB they carry out their mission to ensure the survival of their young. Upon completion of one nursery tube, mama mud dauber lays an egg, right on top of the food supply. Yes. On top of paralyzed spiders. She's done her homework. The spiders will not harm the larvae when they hatch, they will only nourish the larvae. Each species of mud daubers prefers certain types of spiders for their nursery pantries. One even prefers the immature black widow spider for its food supply. Horrifying to me, but mud dauber moms seal their unborn in cylinders with live spiders. However, the precautious moms have made sure that harm cannot come to the next generation.
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