It’s time to put up the bluebird nesting box. It’s still winter, mid-February, but the bluebirds will begin checking out housing in a few weeks.
Bluebirds are one of my favorite bird species. They are about seven inches in length and the males have bright, truly blue heads, backs and wings, an orange-red throat and breast and white belly. The females have a grayish head, back and wings, but edged with blue. They are members of the thrush family, the finest singers in the woods. Their song is a soft, melodious warble that finishes on a slightly lower pitch and with just a hint of sadness to the tone. I love the sight and song of bluebirds so much that I can pick out just a fragment of a song, or a call note, a quarter mile away.
There are three kinds of bluebirds in North America – the Western Bluebird, Mountain Bluebird and the Eastern Bluebird which inhabits areas East of the Rocky Mountains. Once plentiful, North American Bluebirds were in decline through much of the 20th century and their numbers had dropped by an estimated 70 percent by 1970. The reason was largely due to the proliferation of nonnative bird species that were cavity nesters like bluebirds. These species, the European Starling and English House Sparrow, outcompeted bluebirds for nesting sites by aggressively attacking them, driving them off their nests, destroying eggs, killing nestlings and sometimes even the adults.
To reverse the decline of bluebirds, in 1978, Dr. Lawrence Zeleny, founded the North American Bluebird Society to promote the preservation of bluebirds. The main focus of Dr. Zeleny’s efforts was the provision of nestboxes and managing of bluebird nestbox trails. He designed a nestbox that had a small enough entrance hole to keep the larger starlings out, and a hinge on the top so the box can be viewed. The English House Sparrows can still get in the boxes, but Dr. Zeleny stressed monitoring of the boxes and removal of English House Sparrow nests and eggs. The combination of educating the public about the needs of bluebirds, providing them with nestboxes and information for monitoring them has had positive results. In 2005, the Cornell Ornithology Laboratory reported sitings, once rare, of bluebirds all across the southern United States as part of its Backyard Bird Count conducted by thousands of citizen scientists. You can read more about providing and monitoring bluebird nesting boxes here.
Yesterday, I erected a bluebird nesting box on a six foot smooth, round metal pole, attached a baffle designed to keep raccoons from reaching up and destroying eggs or nestlings, and will later affix a metal cage with sharp wire points to keep out snakes. I tried it out on the box, but will screw it in place only after the box is being used by a bluebird, or
other native cavity nesting bird. The birds may be scared away by the cage, but once eggs are laid and nestlings hatch, they will not abandon the box.
I placed the pole and nestbox on the edge of a natural opening in the woods near the summit of Naked Mountain. It is not far from my house and deck, so I can spy on activity, using binoculars, from a distance. I will also monitor weekly to ensure English House Sparrows do not use the box. The spot I picked is exactly the spot bluebirds themselves chose twenty years ago. There was a hollow tree on the edge of the clearing with woodpecker holes on its south-facing side, the preferred direction. The clearing provides the birds with an open area to locate and pounce on crawling bugs. It also provides an intermittent drinking and bathing water source via a bowel effect in the rock formation. A shallow puddle forms there and stays for a few days after a rain shower. I have secretly spied on many kinds of birds, including bluebirds, bathing in the rock puddle. It is totally fun to watch this! I also provide additional water in a birdbath near the house for those hot, dry weeks in July.
The bluebirds fledged two broods for two consecutive summers in that old hollow tree. Then it blew down in a storm. That’s when I started putting up the nestboxes. But two summers ago, my resident pesky bear that I have nicknamed Chobani because he seems to prefer Greek yogurt, predated the nestbox. You can read more about Chobani in the January 28th post on “How To Be Bear Smart On Naked Mountain.” I didn’t put a nestbox up last spring, but Chobani didn’t bother me all last summer, so I am going to try again.
We’ll see what happens this spring. Stay tuned!