Scout Bee

Gwenn Seemel
Liberté, Égalité, Sororité (Bee Marianne)
2024
acrylic on paper
14 x 11 inches

https://gwennseemel.com/artwork/2024/bee-marianne/

Three species are competing for your nest box this week. Two of them you want. One of them you need to manage.

Eastern Bluebirds have been prospecting since early March. Tree Swallows are arriving from Central America right now. Both are cavity nesters, both eat enormous quantities of insects, and both will raise families in your box if they get the chance.

House Sparrows want the same box. And they don't share.

House Sparrows are an invasive species — not protected under the Migratory Bird Treaty Act. When they claim a nest box, they build a messy nest stuffed with grass, feathers, and debris. They're aggressive enough to drive native cavity nesters out, and if a bluebird or swallow is already nesting, the sparrow will enter the box and attack. The results are not subtle — dead adults and destroyed eggs.

This isn't rare. It happens in a significant percentage of unmanaged nest boxes every spring.

The good news is that the fix is simple, cheap, and effective.

🐦 What to do this week:

- Check your boxes for sparrow nests — messy, overstuffed with grass and debris piled high. If you find one, remove it. House Sparrows are not protected and you can legally remove their nests and eggs
- Install a sparrow spooker on top of the box — a short piece of wire with two or three Mylar strips that flutter in the breeze. Bluebirds tolerate it completely. Sparrows abandon the box within days. Total cost about two dollars
- If sparrows persist, plug the entrance hole for three to four days. Sparrows move on to find another site. Bluebirds are more patient and will wait
- Pair two boxes fifteen to twenty feet apart — tree swallows and bluebirds will each claim one and jointly defend against sparrows. This is one of the most effective strategies nest box programs use
- Monitor weekly through April and May — early detection of sparrow activity prevents losses before they happen

The birds are choosing now. A two-dollar sparrow spooker and weekly checks are the difference between a successful nest and an empty box 🌿

Thank you to the native plants that support our native wildlife 🫡