Swifts and the quiet days of July July 15, 2012Posted by Phila Rogers in Birding
By Phila Rogers
It’s this way every year. June’s sunny days end with the arrival of July and the return of the coastal fog. In this summer-dry climate, any moisture should be welcome. I try and appreciate the gray mists enveloping my hill and how the fog-drip dampens the soil and puts a wet sheen on the foliage. When fog drip was measured under the trees along the ridgeline in Tilden Park, an astounding 10 inches was collected – more than a third of our annual precipitation.
What intensifies the gloom for me is the decline of birdsong. It’s tempting to blame the lack of sunshine. But I know with breeding season mostly over, there is less to sing about – no territories to vocally defend, no females to attract. The Spotted Towhees are still singing – not a surprise for a species that typically has more than one brood each spring. Sometimes I hear a stanza or two from a distant Black-headed Grosbeak. Or a robin, undaunted by the gloom or the lateness of the season, sings its cheery song. The irrepressible Bewick’s Wren periodically bursts forth, and out over the open hillside I can hear the plaintive call of a Red-tailed Hawk who can’t quite accept it is on its own now.
Look at the local bird listserve, East Bay Birding Sightings, and you will see that there is now less to report. Only Bob Richmond — reporting regularly from the Hayward Shoreline and knowing the value of place closely observed — has heartening news that shorebirds are once again on the move.
During the brief period of clearing skies, I went out onto the open hillside headed for the pond below Lawrence Hall of Science where you can stretch out under the branches of the big-leafed maple. I find that a sky viewed through green leaves looks especially blue and deep. And what better way to watch for swallows and swifts or the antics of passing ravens than while lying on your back?
Whether upright or supine, I’m always on the lookout for swifts. And when I’m not finding them, I’m reading about them. Early on, I learned that they are not related to swallows as I had assumed, but to hummingbirds. They are hardly sippers of nectars or able to suspend themselves midair, but like hummingbirds, swifts are masters of flight.
“Our” swift is the White-throated Swift. Like other swifts, they migrate south for the winter, though in our temperate climate a few remain and can be counted on to be included in our annual Christmas Count. Because they fly high and fast beyond the range where I can reliably see their markings, I have had to learn to distinguish them from swallows – the other birds of the air and master flyers. When not hurtling through space, swifts often intersperse their swoops and glides with several rapid wing beats, which I think of as “twinkling.” Swifts’ wings are generally longer and narrower compared to their body length than swallows, and the bend in the wing is closer to the body.
Lacking local cliffs, White-throated Swifts are happy to nest and roost under freeway on-ramps, under tiles in downtown Berkeley buildings, and even inside one of the Lawrence Hall of Science ceiling light fixtures.
But it appears I don’t have to leave my garden to witness one of their most remarkable displays known as the “Courtship Fall.” While reading on my garden bench recently, something caught my attention. Looking up, I saw two intertwined birds tumbling down out of the sky. Not twenty feet above the ground, the birds separated, swerved off in opposite directions, uttering a shrill cascade of twittering calls.
With feet poorly equipped to do anything other than cling to a cliff face or the inside of a chimney, they live their lives in the air – feeding, mating, and possibly sleeping. And such a life of exuberance it is – all those aerial displays, the daredevil maneuvers, and that joyful twittering. What heart can fail to be lifted by the sight of the White-throated Swifts who own the sky wherever they choose to fly!
Tags: Bay Area birds, fog, Lawrence Hall of Science, summer birding, swifts, White-throated Swift.