Imagine owning a machine that swoops over your property while you sleep and removes thousands of rodent pests per year. What’s more, it needs little maintenance and does the job at a fraction of the cost of poisoning or trapping. Just such a machine is the barn owl, especially when used in a well-designed nest box program such as the one created by biologist Mark Browning near Elk Grove, Calif.
“Our goal was to determine how dense of a population of owls we could attract, and how that population would affect the numbers of rodent pests,” says Browning.
The results were nothing short of astounding. In 2012, eighteen breeding pairs of barn owls occupied nest boxes on a 100-acre vineyard. They successfully produced 66 young, which eventually joined the adults in hunting the area for voles, rats and pocket gophers. The population removed over 10,000 rodents from the area in that one year alone.
At the heart of the project’s success was a revolutionary new nest box for barn owls made from molded plastic.
“I had installed scores of wooden nest boxes in the East to help with barn owl conservation, only to see them deteriorate. I set out to design a long-lasting box that had all of the features a researcher might want, but also made it easy and economical for growers,” says Browning.
The new nest box caught on quickly. Today it is in use by the Departments of Natural Resources of Illinois, Wisconsin, Missouri and South Carolina, several Audubon chapters, and thousands of vineyards and orchards. It also has been featured on PBS’s America’s Heartland.
Barn owls lend themselves to rodent control programs because they will nest in dense colonies, produce many young, have prodigious appetites, and are highly tolerant of human activity. Their use in rodent control is spreading rapidly across the U.S.
The success of the Barn Owl Box has led to the design of four new nest boxes for screech owls, kestrels, bluebirds, and songbirds.