My husband Patrick is a bird lover. He spots birds and calls out their names to our kids. Birds of prey are a particular love, so when he eyed an advertisement for owl boxes, his interest was piqued. “Takes care of rodent problems,” he said over the morning newspaper, “and we certainly could use some gopher help,” he added. Our back yard looks like a war zone of dirt mounds. Patrick attacks with poison; the gophers continue to munch. Patrick gets infuriated and our yard looks worse and worse.

Tom Stephan

Certified arborist and falconer for 40 years, Tom Stephan (760-789-1493; barnowlboxes.com) has been installing owl boxes for the past 15 years. It’s a business he got into by accident. “I was giving a lady an estimate on trimming a sycamore tree,” he explained, “and she had an owl box on a low branch, and I could tell there were no owls in it. I really didn’t even need to look. I knew it was too low. She told me it was as high as her late husband could put it in the tree, and I offered to move it higher up for her.” She agreed and three days later she called, saying owls had moved into the box. A friend of hers then wanted a box, “and within the first week, I had put up nine boxes. That was the start of the boxes. I have put up over 10,000 boxes now in San Diego County and also in Santa Barbara, Riverside, all over, all the way up to the Oregon border.”

Stephan continued, “The curator of birds at the Natural History Museum called me back in 1994 and asked, ‘How many boxes have you put up?’ At the time, I said, ‘about 250.’ And he asked how many were active, and I said, ‘probably 200 or so.’ And he said, ‘Two hundred nests is about the known population of wild nests for a barn owl.’ So I had somewhere near double the population of barn owls in San Diego County.”

So what is your secret?

“There is no real secret,” he replied. “For any wildlife, you need three things: food, water, and cover, for anything from cockroaches to elephants. Barn owls get all the water they need from the food they eat, rodents, which are everywhere. When Europeans arrived, they altered the environment so much that there aren’t as many hollow trees. The owls nest in hollow trees, usually sycamore and oak trees. So we just provide them with nesting habitat. For the past ten years, near 100 percent of the boxes that I put up get owls in the first year. If you see a barn owl in San Diego County, it is most likely from one of my boxes.”

Why would people want barn owls to nest in their yards?

“According to a study done by the California Department of Fish and Game, one nesting pair of California barn owls could consume as many as 2000 gophers, rats, and mice. An average would be about 1750. That is a big pile of rodents. Nothing competes with barn owls. They are like shrews; they eat, eat, and eat their own weight every night. Barn owls eat around here basically three things: gophers, rats, and mice. They will eat a few insects, but 98 percent are gophers, rats, and mice.”

Stephan continued, “A young barn owl will have as many as 12 babies in a clutch, and from about ten days on, they will eat their own weight or more every night for the next two months. And they spread their clutch out; they don’t lay it all en masse. It is every other day two eggs, every other day two eggs; they spread it out over the whole spring.”

How long will they live?

“If the owl lives through the first winter, they will probably live about six years, maybe up to eight years. But you rarely know if your owls have died because they just go get a new partner right away.”

Stephan offers three different owl-box designs. “All three boxes are made of a tropical hardwood called ‘luan mahogany.’ It’s not a mahogany, but looks like one, with a reddish hue, and the box gets an oil finish to highlight the wood grain. My top-end box, the Hoo’s Who [$950], is a two-story barn with oak trim around the front and the edges and a manzanita branch perch. They come on a 16-foot-high galvanized steel pole set on a post that I set in the ground. Inside the Hoo’s Who is an infrared night-time vision video camera and microphone. It is color in the day, black and white at night, and it has audio; you plug it into your TV.”

“My most popular box is called the Ornate Owl Box [$500]. It looks like a house, has a peaked, oversized roof, trim, and a manzanita perch. There is no camera.”

“The last box is called the Basic Barn Owl Box [$350]. It has a simple flat roof, it’s rectangular, a plain-Jane box. I do everything for the client; I pick out the spot and I install the boxes.”

Where are they installed?

“The boxes installed on poles are only 16 feet high. Some of the boxes that I put in trees are up to 60 feet high, but usually about 35 feet high.”

Is there a certain time of year they should be installed?

“Once peak season starts with some inclement weather, not necessarily rain, could be Santa Anas, fog...the onset of winter. Late October through late December is prime time when mated pairs are looking for a place to nest. The other good season is around June when all the babies are leaving the nest. But you can get owls any time of the year.”