Viper is not labeled for mud daubers; however, personally, if this repels wasps then I would think it would work on mud daubers as well. The product that has worked the best for me is a cypermethrin 40% wettable powder such as the Demon WP or Cyper WP (the generic of Demon). It seems to work better for a longer better of time outdoors and being a wettable powder, the residual effect is better.