Birds on a wire: How power lines can help songbirds

Today you’re hearing from Christine Peterson, a graduate student in the University of Vermont’s Rubenstein School of Environment and Natural Resources. Here she is collecting vegetation data along a power line right-of-way. Credit: Dr. Allan Strong

Many people probably never think about power line rights of way or, perhaps, never even hear of them. But for some migratory bird species, rights of way could provide essential habitat, which is why they have become the focus of my research.

Here is a blue-winged warbler nest we found during habitat mapping. Credit: Christine Peterson

An electric power line right of way (ROW) gives an electric company access to areas where power lines occur, even on privately owned land. In order to access, maintain and repair electric power lines, vegetation along ROWs must be managed to prevent interference. This allows for these ROWs to remain in a shrubby state over long periods of time.

Here’s where the Audubon Society and I come in. The Audubon Vermont chapter of the National Audubon Society recruited local citizen science volunteers to look for priority songbirds to see if our feathered friends were using these shrubby areas created along powerlines. It turned out that four priority bird species, including golden-winged warbler, eastern towhee, blue-winged warbler, and field sparrow were visiting these ROWs. So, as a graduate student, I was called in to take a closer look.

You can find eastern towhees in brush, tangles, thickets and along forest edges. Photo from Flickr Creative Commons user John Beetham.

Last summer, I led a field crew to ROWs across the Champlain Valley in Vermont to follow and map these priority songbirds to see which parts of the ROWs they were using. Eighty-seven birds and two months of very early mornings later, we could see where these shrubland birds liked to spend their breeding time. We then revisited all of these areas to collect countless thorn-induced wounds, as well as detailed vegetation data.

With all of this information, my research aims to paint a clearer picture of how these birds use habitat along powerline ROWs. So… why does this matter?

Only about 15 percent of the preserved land in Vermont is publicly owned. That leaves the fate of much of the land up to private landowners.

Because of this, encouraging conservation and management among private landowners is very important. These particular songbirds rely on shrubby (young forest) habitat to mate and reproduce. It is becoming increasingly hard for them to find this habitat, especially in the Northeast region, as forest recovers and matures from the agricultural boom of the early 1900s. Shrubland occurs as a transitional period between when a field becomes forest again, so it requires disturbance to be created. Using areas like ROWs is convenient because they are already managed or “disturbed” regularly and remain in transition.

In order to access, maintain and repair electric power lines, vegetation along rights of ways must be managed to prevent interference. This allows them to remain in a shrubby state over long periods of time. Photo from Flickr Creative Commons user mwms16.

By examining the patterns of how birds use this habitat and what management is being done, I can suggest management that might better serve these bird species. Audubon Vermont and I collaborated on a report that was submitted to the Vermont Electric Cooperative, which manages over 7,500 acres of ROW land in Vermont. With this information, we hope that future management will create more suitable habitat for these declining shrubland songbirds.

Blue-winged warblers breed at forest and field edges. Photo from Flickr Creative Commons user Matt Stratmoen.

Findings from this research can also help promote important habitat corridors for songbird migration pathways along what is referred to as the “Atlantic Flyway.” This migration pathway is used by a variety of birds traveling to and from breeding grounds that runs along the eastern coasts of North and South America.

During their long migration, birds need places to stop along the way to rest and refuel for their journey. Creating habitat corridors along migration routes can help these birds get to their destinations!