So Regnery and his compatriots at the HPAS devised a plan. Why not adapt the state organization’s initiative into an experiment for the mountains? Brown-headed nuthatches are smaller birds than English sparrows, bluebirds and other species that use boxes with 1.5-inch holes intended for eastern bluebirds, the most common nest boxes in use. By installing boxes with smaller entrance holes, about 1 inch wide, birds that normally have to compete for space with larger avians have a better chance of reproducing.
Science through a diary
While there aren’t any brown-headed nuthatches at the higher elevations, there are plenty of smaller birds that could use some help with nesting sites. The HPAS experiment is looking to install as many pairs of nest boxes as possible in the organization’s area of Franklin, Highlands, Cashiers and Scaly Mountain. One box will have the larger, bluebird-sized hole, and the other will have a smaller entrance.
“Next year about this time we’ll try and get all the data together from everybody and combine it into one nice data set and really sit down and analyze it,” Regnery said.
So far, HPAS has distributed 50 box pairs to individuals and organizations across its service area. Audubon members install the boxes on metal poles — poles better lend themselves to uniform installation than do trees — at least 50 feet apart to keep nesting birds in one box from affecting those in the other. They take note of the habitat where the boxes are installed, and they leave the participants with an observation sheet to fill in as they check their boxes and an identification guide for the birds they’re most likely to find.
“It’s kind of exciting,” Regnery said. “It’s one of the most interesting little programs that our chapter has gotten involved with in recent years that has caught the imagination for a bunch of people.”
Boxes are up at Blue Ridge, Summit Charter and Highlands schools, where students will learn by checking them. They’re also along the Little Tennessee River and at the Hudson Library in Highlands and the Cashiers/Glenville Recreation Center, to name a few. They’re in backyards, being checked by people who are just beginning to learn how to identify birds and at research sites such as Highlands Biological Station, being monitored by professionals. It’s an effort of citizen science that Regnery hopes will get more people to appreciate and help conserve birds.
“Basically what we’re doing is you’re keeping an informal diary of what goes on in the boxes,” he said. “You can be as rigorous as you want to with it as long as we get an idea of what the box is being used for.”
But he hopes that the experiment’s setup could help it to rise above the standard bar for citizen science, which he says often isn’t rigorous enough to really be called science.
This experiment, he said, “may not be science, but it’s getting pretty close and will provide useful data for people and for birds.”
Aside from the uniformity provided by the Audubon members’ installation and the use of metal poles, there’s the construction of the professionally made boxes themselves, which Regnery said are “so uniform it amazes me.” The boxes weren’t available for sale with smaller holes, so excluders that shrink the hole were placed on the outside. But to make sure the presence of the plastic piece didn’t affect birds’ nesting habits, Audubon went ahead and placed excluders on the bigger-holed boxes as well, even though those pieces aren’t actually shrinking the opening.
Each box is also given GPS coordinates. Later, that data can be synthesized to figure out how factors such as elevation, position on the landscape and whether a slope faces east or west plays into how birds use it.
“What would be really cool would be if we could get a graduate student interested in this and they could take it on and do some rigorous statistical analysis of what’s really going on,” Regnery said.
How far the data goes will largely depend on how cleanly it comes back, how well it’s recorded. This year could end up being a rough run, a trial so that next year Audubon will have a better idea of how to make it work well. Or, it could go well enough to become a multi-year effort, engaging Audubon chapters beyond just the one in Highlands.
Bolstering the birds
But birds are wild animals, right? So why should people take so much trouble to provide for them what they’ve been finding in nature for many, many years?
“It may seem like a strange concept,” Regnery said, “but we’ve already reduced the number of trees significantly just by the amount of acreage that we’ve consumed in roads and houses and shopping centers. Whatever we can do to make that up a little bit is sort of money in the bank for the birds.”
Cavity-dwelling birds, which are the ones using nest boxes, often rely on holes drilled by woodpeckers in dead and dying trees. Good landscaping doesn’t usually involve leaving dead trees standing, but when those trees are removed, so is potential habitat for cavity nesters.
Climate change is another factor in the importance of bird boxes. Birds, along with other species, are seeing their geographical distribution change as the climate does. By increasing the number of places available for nesting, Regnery said, we help bolster their populations and give them a stronger advantage over environmental stressors.
“The more resilient we can make these populations, hopefully the better for the future,” he said.
The main species that Regnery hopes to see in the nest boxes are red-breasted nuthatches and chickadees. Neither is endangered, but both are special to the area. Chickadees, for example, are “one of the hallmark species up here,” and they’re important to birders, since they often point the way to flocks of other species of birds.
“When you have chickadees around, frequently the warblers will hang out within earshot of the chickadees,” Regnery said. “I always think of them as the host of the traveling party. I don’t know why that is, but it’s true.”
Red-breasted nuthatches in particular are “not common,” Regnery said, so hopefully the smaller entries will give them a boost.
The record shows that bird boxes do indeed have that power. The now-common bluebird boxes were once a new idea, and before the bird boxes became a fixture in backyards up and down the East Coast, the Eastern bluebird was a much rarer species.
“It’s sort of the poster child for how you can succeed in actually doing this, because now there are more bluebirds than there probably ever have been,” Regnery said.
It’s hard to tell, though, exactly what will come of the experiment. The HPAS is still looking for volunteers to set up the boxes and wants to have them all in place by the time January rolls around, since birds often scout around for nest sites before the actual nesting season.
Plus, having the boxes up early could allow for the data to include more species than just birds. Regnery would be interested to find out whether flying squirrels and mice use the boxes, and he’s hoping that the metal poles the boxes are mounted on don’t prove tempting for black bears to knock over.
“There’s lots of little questions you could ask and answer, so it really is a learning experience,” Regnery said.
A retired microbiologist, Regnery is excited about the scientific potential of the project, having even tossed around the idea of writing it up as a paper, depending on how the results come back. But possibly the most important outcome will be the experience’s power to connect people with their environment — because when people value the environment, they come on board to conserve it.
“We’re trying to give back a little bit when we can,” Regnery said, “and the bird box thing is a fairly rare situation where we can give back a piece of the environment.”
House the birds
The Highlands Plateau Audubon Society is still looking for volunteers to put up nest boxes as part of their experiment to see whether boxes with smaller entrance holes attract different species than standard bluebird boxes.
Individuals can purchase box pairs at cost — $35 buys two boxes with metal poles and installation by Audubon members — and the boxes are theirs to keep. A data sheet and identification guide to common birds are also part of the deal, but participants must take two boxes or none at all, and they should be willing to check the boxes regularly to record their findings. Boxes should be set up by New Year’s Day, but early bird recording is encouraged.
Free boxes are available for public areas and schools through a $1,000 grant the Mountain Garden Club provided for the project.