Turtles.

Juvenile turtles have the capacity to eat more than 500 3rd and 4th instar mosquitos per day. Keeping one turtle in each water-storage tank during field trials for a dengue-control project in Honduras eliminated all mosquito production from the tanks. In Louisiana, keeping turtles in residential roadside ditches polluted by septic-tank effluent reduced Culex quinquefasciatus larvae and pupae by more than 99%. Turtles can serve as alternate hosts for Salmonella when kept in small pet containers, but the available evidence indicates that turtles create no Salmonella hazard in water-storage tanks or other mosquito-breeding habitats. Although turtles would probably not be practical for mosquito control in roadside ditches, they could be effective in storm-water catch basins or holding ponds.