Nest Boxes: Manage, Maintain, & Monitor

The Three Ms of Nest Boxes: Manage, Maintain, & Monitor

By Krista Botting, Summer Field Biologist

Being the “landlord” of a nest box doesn’t have to take up a lot of time, but it’s not a good idea to put one up and forget about it. Without proper care, nest boxes can attract unwanted visitors or become a death trap for eggs and nestlings. Here are a few tips for managing, maintaining, and monitoring your nest box!

Security

Your top management priority should be predator prevention. Snakes, racoons, cats, and other critters are always looking for fast food—and that includes eggs and baby birds. It’s pretty simple to attach a wire mesh box around the entrance hole or add a baffle or cone to the mounting pole. This will keep predators away from the nestlings. Project NestWatch has a great guide on predator-proofing your nest box.

Squatters

Watch out for unwanted squatters, particularly House Sparrows. House Sparrows are invasive and not native to North America, and should be prevented from nesting if possible. If you observe nest building activity by House Sparrows it is best to remove the nest from the box. Repeat the eviction if necessary (sometimes several times), eventually they’ll get the idea and not come back. House Sparrow nests tend to be messy in comparison to an Eastern Bluebird’s smooth, bowl-like structures. If you can’t identify the species by the nest, observe the nest box for a time to see what bird is flying in and out of it.

Nest boxes can also attract other wildlife, especially if you leave up the box for the winter. Bigger boxes are a cozy place for squirrels (including the flying variety) to hole up, and mice will certainly make themselves at home in smaller ones. These critters aren’t really a problem, but if you let them stay past winter they may compete with the avian life you want to attract.

It’s a good idea to empty a nest box out at the end of the breeding season once you haven’t observed any activity there for a while, and certainly before breeding season rolls around the next year. If you want to keep mammals away, but not take the box down, be sure to check on it periodically throughout the off-season.

Be Your Birds’ Handyman (or woman!)

Inevitably, wood breaks down, nails pop out, and screws become too tough to turn. While you keep an eye on your nest boxes for signs of life, also watch for signs of wear and tear. Most often you’ll find that some piece of wood has split or a woodpecker has taken to drilling into the side of the box or even widened to entrance hole. When this happens, it’s best to replace that one piece of wood or the few screws or nails that have come loose.

If the mounting pole becomes wobbly, it’s not a disaster. Birds will still come to nest, but the box has a better chance of falling over in a storm if it’s already a little tipsy, or that a predator will be able to reach into the box.

Fix whatever you find necessary, but always make sure there isn’t an active nest before you mess with begin taking apart the box or disrupting the area too much. Birds first, maintenance second.

Watch for New Tenants

It’s best to put up a nest box just before the nesting season begins and take it down for the winter. Timing may vary slightly among species, so check eBird to see when the species you want to attract start returning to your area. Once you have set up a nest box, monitor it from a safe distance using binoculars. If you see birds coming and going with nesting materials, DO NOT APPROACH. Disturbing birds during the nest building or early incubation stage may cause them to abandon the nest and eggs.

Resources

The Cornell Lab of Ornithology’s All About Birdhouses page is full of information about identifying and preventing predators, nest box maintenance and monitoring, and more.

And while you’re there, check out Project NestWatch to learn how your observations can help scientists.