Local Bluebirds Thrive, with Help
By Theresa Curry
It’s not always a happy life for bluebirds, those vivid symbols of spring and joy. Rat snakes plunge from nearby trees to invade their homes and eat their eggs, and house sparrows trap them in their nests, attack and kill them. And invading development gobbles up the open land that gives them a territory for hunting along with the old trees that provide hollows for nests.
Luckily, they have a lot of human help. “And luckily, they accept our help,” said Ann Dunn, who monitors the bluebird trails in Mint Springs Park as well as others in the Charlottesville-Albemarle area, Mint Springs is one of the oldest trails, established in the 1980s by Bob Hammond. Later monitors were Bill Minor and, more recently, Ron Kingston.
Dunn credits Kingston as a local pioneer who began establishing bluebird trails throughout the area more than 30 years ago. “He continues to be very active in this program and has monitored and maintained the trail at Mint Springs for the past eight years,” she said.
Besides being loved for their beauty, bluebirds are sought after by gardeners because they eat the worms and insects that prey on garden plants. “We’re used to seeing robins perched on the ground, pulling worms out of likely spots,” Dunn said. The bluebird style is different: they watch the ground from a branch and swoop down on the unsuspecting caterpillars or spiders below. They’ll also eat winterberries, holly berries and other small fruits.
Dunn’s a retired lab biologist who moved to Charlottesville with her husband to work in a lab at U.Va. In retirement, she became a master naturalist, with a particular enthusiasm for birds. “Now I’m more of a field biologist,” she said.
After accepting the care of the local trails from Kingston, she’s learned some additional skills, including repairing the bluebird boxes and the guards that discourage snakes from slithering into the openings meant for nesting pairs. She’s learned to recognize the nests of the nefarious house sparrow by the sloppy construction. “They incorporate cigarettes, chewing gum, almost anything,” she said. She’ll remove this invasive species to make room for the more useful and pleasant bluebird that prefers a tidy little nest of grasses and pine needles. “We also welcome tree swallows, another helpful, native bird, in the boxes.”
On a chilly March morning, Dunn was inspecting the seven boxes in Mint Springs. “No nests as yet,” she said, “but that’s a good sign.” Birds that settle down in the boxes too early face weather-related challenges. She travels with a number of tools for making repairs, as well as a stool to reach the 7- to 8-foot high boxes. Boxes face northeast, towards the entrance to Mint Springs, to minimize mid-summer scorching. Most typical is the bluebird pair with one nest of four to seven eggs per season, although bluebirds may have as many as three families in a season in this area. There’s usually a diminishing numbers of eggs each time. “Towards the end, they are just exhausted,” Dunn said.
Over time, bluebird monitors have learned that it’s a tricky balance, she said. The boxes have to be easy enough for a monitor to open fairly quickly with a simple screwdriver, but a little too difficult for a curious passerby, not to mention a curious bear. And the metal guards that keep raccoons or snakes from bluebird home invasion have to prove a substantial disincentive to potential intruders but fairly harmless to someone who bumps up against one to catch a frisbee. Generally, “we wait until there are signs of a predator problem before installing the guards,” she said.
Locally, bluebirds are thriving. Dunn keeps statistics for Virginia, and reports that the number of fledglings per nest box in Albemarle and Fluvanna counties has held steady, with a spike in 2013—most likely due to the cicada hatch, she says—and a dip in 2014 that reflects the weather extremes of that year.
A suitable and safe nesting site, watching over open land but with nearby trees, is essential for successful nesting. It’s also the male bluebird’s claim to paternal worthiness. Typically, he positions himself near a desirable home with a beak full of grasses suitable for nest-building as a visual proof that he’s a good provider. It’s a pose for the benefit of the area’s female bluebirds, who actually do the nest building.
So it’s a lucky thing for local bluebird bachelors that Clark Walter, an Ivy resident with a well-equipped shop, became interested in building bluebird boxes. Clark, who had worked for various international programs to fund the arts, private charities and to prevent species extinction, met Dunn at a local master naturalist class shortly after he retired. He invited her to examine his Owensfield Road property for its suitability for a bluebird trail. Once the two mapped out the best sites, Walter asked for plans and offered to build his own boxes for the trail. People from the master naturalist class, then the Virginia Bluebird Society, and then random bird lovers all over the country asked him for boxes, and the requests just kept increasing, he said.
To say that Walter has refined bluebird-box building to an art is an understatement. A very organized man, Walter ran his “Captain Breck’s Buttery Good Rumcakes” business alongside his work and other interests, and after he retired, operated “Captain Breck’s Custom Carpentry.” He knew the value of ordering in bulk and planning for efficient production. Before assembling the hundreds of nest boxes this last October, Walter had cut and pre-drilled all the pieces and parts, and stacked them in sequential order ready to assemble. He uses spreadsheets to track orders.
Neighbors began noticing forklifts of metal and huge stacks of lumber unloading at his shop door as his orders expanded from materials for 20 nest boxes in 2012 to more than 600 in the fall of 2016, along with hundreds of poles and predator guards. Walter won the 2015 volunteer award from the Virginia Bluebird Society for his work. “When I’m in full production, there’s only a tiny bit of space left for me to work in.” He said he sees no end in sight.
It’s all worth it, he said. “It’s spreading happiness on the wings of bluebird diplomacy.”