Tips from an Audubon expert on how to build a proper birdhouse

Larry Zoller is attuned to the sounds of birds. During conversation, he’ll pause if he hears one and then identify it.

“Red-shouldered hawk,” he’ll announce, or “red-bellied woodpecker,” before resuming what he was saying. Appropriately, this bird-fascinated man — a retired teacher — is the president of the Wake Audubon Society. Also appropriately, there are bird boxes throughout the yard of his suburban Apex home. Some are designed for bluebirds and nuthatches but one larger one, built for a screech owl, currently houses a different kind of beast.

“I love God’s creatures, but squirrel is not high on my list,” Zoller says with a smile.

Squirrels, after all, are only one animal that can displace birds from these boxes; others, like snakes, cats and invasive birds like starlings, can attack and kill birds if their homes aren’t built or placed properly.

Zoller provided us with handy tips on building sturdy, practical bird boxes. For those who want to go a step further and decorate the boxes, Zoller’s tips could be used to ensure the birdhouses are not only creative, but useful and safe for their target residents.

For the humans placing birdhouses in their yards, the rewards can be both ethical and aesthetic.

“Make sure it’s away from predators, but make sure it’s where you can see it,” he advises. “That’s where the value is.”

Having been an avid birder for five decades, Zoller says a bird box is a good entry point to the world he loves.

If you have a bird nesting in your box, he posits, you’ll learn more about it. And if you discover there’s pressure on the species living in your yard, you’ll want to do what you can to help that bird survive. The brown-headed nuthatch, he says, is one species warranting concern. Through research, the National Audubon Society has found that it and other birds will soon be absent statewide because of climate change, Zoller says. Experienced birders keep tabs on this population change through regular counts.

“Their range will move, but a number of them will go extinct — in fact, a surprising number,” he says. “If you were going to go to the Audubon website and check it out, you would find that it’s a shocking percentage of birds that either won’t be in North Carolina or will be gone from the face of the earth.”

As it gets warmer, he explains, birds can’t just move their ranges; the temperature may change, but the ecosystem these creatures are adapted to won’t simply move with it.

“When miners used to go in a cave they’d have a canary, and the bird would die,” Zoller says. “Well, these birds are our canaries.”

PHOTOS BY JULI LEONARD/RALEIGH NEWS OBSERVER/TRIBUNE NEWS SERVICE Larry Zoller, the president of the Wake Audubon Society, holds a bird box in his backyard.

Door holes are different sizes for different birds: an inch and a half hole, for instance, allows bluebirds in but is narrow enough to keep more aggressive starlings from entering and pecking the bluebirds. Squirrels can chew up door holes to get into...

Inside and below the hole there should be a “ladder” of grooves so nestlings can climb out.

If you pre-drill holes in the side walls and top of the front panel and then attach that panel with galvanized deck screws, you can open the front to clean your birdhouse.

When building a birdhouse, recess the base and cut off its corners so water doesn’t gather inside the house.

Ensure that the birdhouse has vent holes so its residents don’t overheat.