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Tree Swallows Have Decision Making Issues



Dear Bird Folks,

Last week a pair of Tree Swallows landed on one of my birdhouses. I was thrilled at the thought of swallows nesting in my yard. But then the birds left and I didn’t see them for days, until they returned this morning. This time they checked out a different birdhouse and then they left again. What’s going on? Do you think the swallows will use any of my birdhouses this year?

– Chad, Truro, MA


You probably already know, Chad,

I wish there was a quicker way to answer some of these timely questions, but unfortunately there’s a lag between the time I receive a question and when it makes it into the paper. Here’s how the process works. First a truckload of questions is delivered to a secret warehouse, where a team of interns sorts them into categories. Then a panel from the Smithsonian Institution selects an entry from each category and forwards them to the official ATBF editors, who then choose that week’s question. All of these steps create a delay between the question and the eventual answer. So, at this point you probably already know if the swallows are using your box or not and I don’t even need to bother responding. However, I’m going to answer your question anyway. I hate to disappoint the Smithsonian.

Tree Swallows are one of our most underrated backyard birds. People are often more fixated on Purple Martins because they think martins will eat lots of mosquitoes and because they love the idea of putting up a showy birdhouse that looks like Tara from Gone With the Wind. The truth is martins are difficult to attract and eat very few mosquitoes. Instead, I suggest to folks that they invest in a Tree Swallow house. Tree Swallows are much easier to attract, they eat lots of bugs and will readily come to a basic birdhouse. It’s at this point I lose the martin lovers. When I show them what a swallow house looks like, which is plain and simple, their faces drop faster than the reputation of Carnival Cruise Lines. Plain birdhouses aren’t going to cut it with martin people. They say they want to attract birds, but what they really want is Tara.

For anyone who doesn’t know, Tree Swallows are 6”-long swallows with shiny blue-green backs and bright-white fronts. They are called “Tree” Swallows because they nest in old woodpecker holes and other tree cavities. They will also come to birdhouses, all kinds of birdhouses, but the less the houses look like Tara the better. Tree Swallows are energetic, handsome birds; however, they have one major problem. They have serious commitment issues. It takes them forever to choose a nest site. Even after they appear to have finally made a choice and have spent several hours fussing and fighting over a nest box, they will suddenly up and leave the entire area and not return for days, if at all. Where the birds go during this absence is unclear. We aren’t sure if they are off looking for better accommodations or if the couple has simply gotten into a domestic squabble over the color of the wallpaper. (Believe me, I know what that’s like.) Sometimes swallows will place a few pieces of grass or straw in the box before leaving. Realtors call this a good faith deposit but I think it’s more like the lawn chairs we put out to save “our spot” at a Cape League baseball game.

As the couple is trying to decide which birdhouse to take, the female has her own problems with commitment. While the male is setting up appointments with every real estate agent in town, the female sneaks off to “visit” other males…just to be sure she hasn’t missed out on a better option. Even after all the debate is over and the official nest site is finally chosen, the pair still seems reluctant to build their nest. The Ospreys near my house constructed their giant stick nest in a matter of days, but swallows may take nearly a month to build their tiny grass nest, in a cavity that was already built for them. They just hate to commit. Eventually, the swallows get down to the business of laying eggs and raising baby swallows. If you are lucky enough to have a pair nest in your yard, you will definitely be entertained. Many birds are secretive about where their nests are, but swallows love to show theirs off. The birds will sit on the birdhouse and sing away, or at least do what they call singing. Tree Swallows have a non-musical, high-pitched bubbly voice, which sounds like Tiny Tim gargling with pudding. (Worst analogy, ever.)

By the time this newspaper goes to print, Chad, you probably already know for sure if the swallows have returned to use one of your birdhouses. So, I’m not going to make any predictions. Besides, I don’t really have the ability to forecast bird behavior. If I had any clairvoyant skills at all I wouldn’t be selling birdseed for a living. I’d be in Florida buying Powerball tickets. One final thing: In addition to commitment issues, Tree Swallows have one other strange behavior. They have a deep-rooted feather fetish. With humans it’s dark chocolate or lingerie, but with swallows it’s white feathers. Sometimes they’ll spend hours fighting over a single white feather, which eventually ends up in the nest. I find this a little strange. Why would birds get excited about feathers? Aren’t they covered in feathers? Maybe someone should tell them about chocolate and lingerie.