Their twittering notes and whizzing wings create a musical, but wild, continued roar. The twittering, whizzing roar continues to increase; the revolving circle fast assumes a funnel shape, moving downward until the point reaches the hollow in the stub, pouring its living mass therein until the last bird dropped out of sight.
~Chief Pokagon, of Potawatomi tribe, 1897
People have long been fascinated by the gatherings of migrating chimney swifts, Chaetura pelagica. Each autumn, they gather in large flocks and seek out large chimneys in which to roost for the night. Of course, as my friend and chimney swift advocate, John Connors, says, they probably would have gone by another name a few hundred years ago, before chimneys became such a common sight on the landscape. Perhaps hollow tree swift? I personally like a phrase many people use to describe the way they look…flying cigars.
The NC Botanical Garden recently had a lecture and a field program on chimney swifts, led by John, as part of their Saving Our Birds initiative. To prepare for the field portion, Melissa and I helped out by looking for a suitable roost site in Chapel Hill. Local birders suggested the chimney at the downtown post office had been used in the past, but when we arrived, it looked to be capped, preventing the birds from using it. We scanned the sky at sunset, looking for the tell-tale rapid wing beats of swifts. They tend to arrive as the sun is setting, a few at first, flying in wide circles high in the sky. Over the next half hour or so, the flock adds members and they tend to fly a bit lower. The birds were flying near us, but we could see several chimneys that might be suitable so we split up, looking for the swirl of birds that signifies the roost location. Finally, we both spotted the swifts beginning to circle in a location across Franklin Street from where we were. We rushed over and found them swirling around a small chimney on the back side of a row of businesses along the busy main drag of Chapel Hill. They started dropping in as darkness neared, even though this particular chimney provided some challenges to an easy entry. It had an arch over the opening and was topped by a large antenna. What amazed me was how few people in the crowds on the street seemed to notice this twittering tornado of a few hundred birds just above their heads.
On the night of the program, a group of 40 or so birding enthusiasts gathered on a plaza with a good view of the sky and listened as John explained some of the marvels of these masters of flight. Here are just a few of the fascinating facts he shared about these winged wonders:
Among the most aerial of birds, chimney swifts fly almost constantly, except when roosting for the night or nesting. They feed, bathe, and may even nap on the wing.
Instead of perching on branches like most birds, they use their long claws (and brace their bodies with their stiff tail feathers) to cling to vertical surfaces like the walls of chimneys or the insides of hollow trees.
They use a glue-like saliva to cement their twig nest to the chimney wall.
We hurried across the street as storm clouds gathered and were rewarded with the sights and sounds of a few hundred swifts doing what others of their kind were doing all over our state at that same moment – making a living swirl of feathered creatures seemingly being sucked into a chimney for the night. I went back a few nights later to record a few moments of this phenomenon…
As the sky darkened, they started to maneuver into the narrow opening by dipping and dodging downward into their roost for the night.
John told our group that this species, one that has adapted so well to the presence of humans, is now facing threats. Nesting chimneys are rapidly disappearing as construction techniques have changed and people tend to cap their chimneys. Plus, the phenomenon of roost chimneys is also in rapid decline as more and more of the large old chimneys are torn down or capped. This is such a shame, as it is one of the few spectacles of nature that is often readily available to urban dwellers. John wrote a recent op-ed piece on this dilemma in Raleigh’s News and Observer that provides a great overview of the issues surrounding this species.
Awareness and concern about the plight of this species helped it become NC Audubon’s 2016 Bird of the Year. Check out that link to learn more about what we all can do to help this amazing bird.
And, you may want to check out this chimney swift live cam from a large roost in an old industrial smokestack in Detroit. Look in the evening over the next couple of weeks. I watched it last night and saw the first swift enter about 7:40 p.m. By about 8 p.m. they were all in for the night. Be sure to check them out in the morning as well as it takes some of them awhile to leave. Soon, the large flocks will move on toward their South American winter home. Before they return next spring and begin to search for suitable nest sites (only one pair nests per chimney), find out how you can help these remarkable flying cigars maintain their centuries old relationship with our species.