A customer reported $275 damage to trolling motors after the critters filled the units with mud. He later experienced significant expense to repair an ATV after daubers blocked airflow to the motor. They’ll build a nest in any nook or cranny.
Annoying mud dauber nests are one of those “symptoms” we discussed last month. If you’re fighting this battle, we’d wager you’ve noticed numerous spider webs. Guess what daubers pack in those mud cocoons for developing larvae to eat. Yep, spiders.
Females prey upon all spiders, especially black and brown widows. They likely homesteaded your area after finding a bug bonanza. Instead of stocking one or two large spiders, they prefer particular types and sizes. Two dozen small ones may be crammed into one nest cell. They appear to know exactly what they’re hunting and where to find it.
Scraping away nests only eliminates half the problem. They’ll build it back almost overnight. Complete treatment requires application of Viper insecticide or similar product. Eradicating the spider population should send daubers in search of new feeding territory.