Owls will keep down the rodent population anywhere they inhabit.
Within a season a group of owls can eliminate a population of several hundred mice and other rodents.
By putting out rodenticide, not only would you be able to eliminate far fewer rodents, but you would also poison the important owl population, as well as other animals and pets.
California wineries are now using owl nest boxes in their vineyards, and seeing a difference in rodent control.
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