Bluebirds

By Beth Sullivan

During late winter, things can get pretty dull and depressing. We all look for a spark of color in our landscape.

Lucky for some of us that the spark we see is the most beautiful blue. During the winter, our local Bluebirds do not migrate, at least not far. Mostly they roam in loose flocks through woodland areas to look for berries remaining, even dried, on shrubs and trees. I see them in places where there are the blue fruits on the evergreen Cedar trees in and around some of our preserves. Fennerswood, Knox Preserve, Preston Nature Preserve, and Knox Family Farm are just a few with the essential field habitat adjacent to cedar groves.

This male Bluebird clings as easily as a Woodpecker to the suet cage.

This  female waits patiently nearby while her mate takes his turn at the suet cage.

During February I think Bluebirds tend to become more desperate and begin to seek out bird-feeding stations and will join the suet lovers. This is my favorite time because it brings them close to my house, right in front of my kitchen window, where I can watch them cling to the suet as if they were woodpeckers. They can become pretty territorial too! I have seen them flaring tempers at Downy Woodpeckers and Nuthatches. But I have also watched some tender sharing moments as a Bluebird couple deliberately and politely, take turns on a suet block while the mate sits on a nearby branch or porch rail waiting.

Tempers flare when they have to share.

Spring house hunting

By late February or early March they have begun moving back to the fields and start searching out nest boxes. If you are a Bluebird landlord, you know it is time to clean the houses, remove old nests if you left them from last year, and get rid of mouse nests and debris that has accumulated. A clean house harbors fewer overwintering pests and parasites.

Cleaning out old nests insures fewer parasites for the new occupants. Photograph by Ethan Frohnapfel. 

Check to make sure your predator guards are intact and that your latches function so you can get in during the season to check on things. Unfortunately the “things” that need to be checked on are invasive House Sparrows. There are very few creatures that I really dislike, and I have tried to give credit for House Sparrow’s adaptability. But for several years running I have witnessed their cold blooded murders of nesting Bluebirds and Tree Swallows, destroying eggs, killing young and adults alike. Once I found an entire, new, Sparrow nest built on top of the bodies of the Tree Swallows that nested there first.

A House Sparrow built its nest on top of the Tree Swallow it killed to take the nest box.

That meant war. They are not protected by the laws that protect our native songbirds, and even the DEEP and USFWS encourage removal by whatever means possible. I will remove nest material, remove or addle eggs, and beyond that you don’t want to know.

Making Bluebird-specific nest boxes

But there are some new and ingenious methods to be found on line, to fix your houses to thwart Sparrows that do not deter Bluebirds or Swallows.

Now is the time that the Bluebird pairs check out available real estate. Photograph by Rick Newton.

One of our volunteers has made skylights in the top of the bird houses and created a plexiglass roof cover . Apparently the Bluebirds like the extra light and the sparrows do not. We have one as a trial at Knox Preserve.

A skylight is welcomed by Bluebirds but unattractive to House Sparrows. Photograph by Ethan Frohnapfel.   

Another volunteer steward has outfitted the boxes there with a special design using fishing line. The line really bothers the sparrows and prevents them from perching, but the bluebirds have no problem with it. Follow this link for more information. 

For more information, here is a link to the DEEP Bluebird Fact sheet. 

The DEEP would like all Bluebird landlords to report their successes, and failures-those are important too. Follow this link to fill out their survey.  

Together we can find the best methods to support these most beautiful of our birds-our spark of blue at the end of winter. Welcome to spring nesters.

Photographs by Beth Sullivan unless otherwise indicated.