Humans are not the only mammals looking ahead to spring. By late winter, resident birds are scoping out real estate for the upcoming breeding season. Increasing the local housing supply is a great way for you to help birds and spruce up your yard, but only if you know what you’re doing. In fact, putting up the wrong bird house in the wrong place can do more harm than good.
Many birds have very specific requirements for the location of their homes, and for the dimensions, including the size of the entry ways.
“Bluebirds are really picky,” explains Caras Nursery Store Manager Marlise Flynn. “They want an incredibly specific hole size and they want the house to be in a wide open place. They want it to be on a post in a field so they can see what’s there before they go home.”
Chickadees, wrens, and nuthatches prefer smaller homes than bluebirds but are equally picky about their entry ways, preferring holes that are between 1-1/8” and 1-1/4” in diameter. One reason hole sizes are so important is that if you put out a house with a hole that’s too big, you won’t attract the native birds that need our help. Instead, you’ll invite harmful invasive species such as European Starlings and House Sparrows.
“Starlings are super aggressive birds,” Marlise says. “They’re not native and they’re just very prolific. If a bird makes a nest, a starling will take that nest, kick the eggs out, and claim that nest as theirs.” Marlise recommends taking down bird houses and feeders if you have starlings around but every person’s situation is different. At my own house, starlings began nesting in the ventilation holes under my roof. I was able to buy round plug-in screens to seal these holes and drive the birds away while still keeping my bird houses and feeders in place.
House Sparrows are another invasive species. At my home, they bully and harass nesting chickadees, even though the holes of the chickadee houses are too small for the House Sparrows to use. However, they are a good lesson in the importance of hole diameter. While many bird houses accommodate chickadees, nuthatches, wrens, and House Sparrows, I order houses with 1-1/8” holes specifically for chickadees and nuthatches, and have found that they effectively exclude the sparrows.
Caras Nursery in Missoula or Birds & Beasleys in Helena carry a wide selection of bird homes, or you can order homes and other bird products through Woodlink.com—and don’t forget about bats!
“We have lots of bats in Missoula,” Marlise says. “They’re a natural animal in this area, and if you bring them into your yard you help control mosquitoes and bugs.” Bat houses have openings underneath them to allow the mammals to fly in and roost.
To ensure success of your bird or bat house, here are a few tips:
- Place the house at the proper height for the birds or bats you wish to attract.
- Place bird and bat houses in the shade, facing north or east so that you won’t “bake” your guests.
- To improve survival, provide drinking water for your birds, especially in the tougher winter and summer months.
- Keep all cats indoors. While valued by us, cats are an invasive species that kill between one and three billion North American birds each year. Keeping kitty indoors keeps birds safe, and protects your cat, too!
- To avoid the spread of disease, clean out your birdhouses after every breeding season.
- Plant native plants such as golden currant and buffalo berry to provide added food and shelter for native birds.
Sneed B. Collard III is the author of more than 85 books including the humorous memoir Warblers and Woodpeckers: a Father-Son Big Year of Birding. Contact him through FathersOnBirding.com and www.SneedBCollardiii.com to learn more and inquire about personalized birding tours of the Missoula area.
