Winemaking is a delicate craft involving subtle combinations of soil, rain, heat, and sunlight.
But, there's also the problem of the pesky interference of mice and gophers which, historically, vintners often turn to pesticides to solve. In an effort to find a more natural solution, a team of students at Humboldt State University in California has been testing the merits of the age old practice of using owls to hunt rodents.
The researchers placed around 300 owl nest boxes in random places through vineyards in Napa Valley in the hope the owls would offer a feasible natural alternative to pesticides.
The students surveyed 75 wineries in Napa Valley, 80 percent of which reported a significant difference in rodent control since they started using the owl nest boxes. During the nesting season - which is around four months - barn owls spend about one-third of their time hunting in the fields. On average, a family of barn owls eats about 1,000 rodents during the nesting season, and whopping 3,400 in a single year. That, of course, is a lot of pesky rodents being removed from the equation.
So far, the study has revealed that the owls were doing a pretty good job at reducing the number of gophers in vineyards, while the number of mice hasn’t been affected. With that said, the key part of the study is whether the owls are leading to a decrease in rodenticide use in Napa Valley. Happily, most of the participating vintners report using no poison since the owls were introduced.
That's also good news for other birds and animals that eat rodents poisoned by the rodenticides as the poison can kill them too.