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Posted by: atowhee | May 6, 2018

SWIFTS ARE AMAZING

Our local Vaux’s Swifts are small, the smallest in North America.  They are larger than some island swiftlet species, but much smaller than the Chimney Swift of eastern North America or the species in Europe (Common, Alpine, Pallid). There are about 95 species of swift in the world and on every continent except Antarctic though they avoid really cold climates and high altitudes.  Every time I see one speeding through the sky, passing swallows in the slow lane, I must remind myself exactly how unusual and marvelous these birds are.

It is less than five inches long, but has a twelve inch wingspan.  That’s a longer wingspan than the Spotted Towhee which is several times bigger in bulk.  Other swift species measure between four inches and 9.5 inches in length.  Swifts are the fastest bird on earth in level flight–regularly reaching 70 MH, while one species has been clocked at 100 MPH.  Some swifts use bat-like sonar echolocation when returning to roost site in the dark.

The Vaux’s Swifts winter in Central America and coastal Venezuela.

They live most of their life on the wing.  Sometimes flying for months without stopping. We now know something of swifts’ lives thanks to nano-technology and our digital tracking ability.  Here’s a video on the European Common Swift.  We now surmise a single bird can fly hundreds of thousands of miles in its lifetime, click here.

I found this fine video of swifts in slow motion and you can see them close in on flying insects and swallow them.

Most touching video I found: ceremony welcoming the swifts back to Jerusalem in spring.

WATCHING SWIFTS

It would be redundant to say “watching swifts in flight.”  I continue to search for the words.  Not even video does then justice, words about their flight are as shadows speeding past a window.

Vaux’s Swifts inhabit the sky right now.  Any time from dawn to dark you may see one or more crossing beneath cloud or blue.  No other creature flies the same way.  The arc-shaped wings beat rapidly several times, then stop as the body speeds onward.  The swift motion through the sky seems too fast for deliberation. Yet they run down insects and other small fly [sic], and swallow them with wide mouth fully open.  At one moment a swift will head straight, then suddenly carom off an unseen edge, loop back around, zig-zag off at a step angle, dropping or climbing to a new altitude. I occasionally see them dip one wing, perhaps this helps them make a sharper turn? They seem to reverse direction with no effort I can discern.  The swifts live and move so swiftly our meagre eyes cannot keep up.  We are so slow. At times you can hear them signaling to one another, a cranky sound not confused with song or music.  We now know they can migrate at a height of thousands of feet above the earth, feeding on aerial plankton as they travel.  Here to breed this summer these small swifts are only slightly more earthbound now.  They do not stand, nor perch, nor belly down on a limb to rest, they fly.  Only rarely are they not in flight.  Then they hang in a chosen chimney or hollow tree, head down like a bat. For some swifts this happens only during nesting season.SWIFT UPPPPA tiny fleck of life among that tremendous expanse of air, every direction a possibility.SWIFT2 UPPPPIn migration after breeding this species is most abundant in western Oregon during the first half of September.  There are several well-known, perennially popular roost sites along their route.  Three locations that can attract thousands of swifts in one night (plus hungry raptors): Chapman Elementary School in Portland, Agate Hall in Eugene, the old brickyard chimney in San Rafael.  I have found modest numbers roosting in chimneys here in McMinnville. Check your neighborhood this fall.  They need old chimneys without slick metal or ceramic linings so they find crevices and uneven surfaces where their tiny toes can get a grip.  Last year we had one pair nest in our chimney, we hope for a return.  Before the white man our swifts used hollow trees for nesting and roosting.  The Black Swift of the West nests behind waterfalls.  In the tropics some species use hanging palm, fronds, others use caves.  Fortunately we have provided chimneys as we have certainly decimated the supply of old, dead trees left standing in the forest.

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