By Mel Carriere
Image attributed to: http://utahbirders.blogspot.com/2014/05/utah-big-day-record-pt-1-scout-route.html
If they play tennis at night, which I'm not really sure they do because I'm not much of a fan of the sport, I wonder if Serena Williams or her sister ever looked up and noticed the remarkable nighthawks engaged in amazing, fluttering flight among the flood lights above. Even though I do not play tennis at night, I have been to places where they do, and have stood in awe of this spectacle - not at the amateurish, clumsy swings of the tennis players, but of the smooth, precise, coordinated flight of the Lesser Nighthawks catching bugs in the lights.
As it turns out, tennis courts are a mini ecosystem. In addition to the primates sweating and grunting down below as they make crude, awkward attempts to imitate the graceful and beautiful Serena, there are hundreds of moths, beetles and other bugs attracted to the brilliant bulbs that illuminate the courts, and following these bugs are the predators that feast upon them, including perhaps a few bats that pass by incognito because their dark coats blend into the night above, and also the Lesser Nighthawks whose wingtip safety reflectors and bright strip of reflective tape across the chin clearly announce their identity for the spectators at the courts.
I accompanied my son to the park a few nights ago so he could do his jogging. As he slogged around the park's pathways, I sat outside the gym and watched the parade of Nighthawks that were circling around the tennis court lights across the way. There must have been at least a dozen of the birds, but it was impossible to count because not all of them were illuminated at the same moment. The Chordeiles acutipennis would dash and flutter in, scoop up hordes of bugs in their enormous bug shoveling gapes, then vanish into the darkness beyond the range of the glare of the floodlights.
One thing about Lesser Nighthawks is that, even though they straggle into work in rather lackadaisical fashion, once they are on the clock they are all business. I have seen them commuting slowly in from the higher sage scrub around dusk, appearing to be fighting off the effects of a bender the day before, dipping and swirling in a rather aimless, pointless fashion, as if they were trying to delay the inevitable, like we all do when we have had a rough night but we still have to make a living. Once within the limelight of their tennis court theater, however, the flight of the sluggards instantly transforms from haphazard into precise as they pirouette about the flood lights with swiftly executed, geometrical turns. Although they can glide a straight line as efficiently as any raptor I've seen, Lesser Nighthawks alternate their smooth, flapless flight with a rapid fluttering motion which made me think of bats as I sat there and observed.
This line of thinking took me to the concept of convergent evolution, which basically means "...the independent evolution of similar features in species of difference lineages (per Wikipedia)." For instance, bats and Nighthawks are nothing alike, one being a mammal and the other a bird, but they have evolved a superficially similar pattern of fluttering flight, and I couldn't help but wonder if chasing insects on the wing requires these quick wing beats. It seems that swifts and swallows also pursue bugs through the air using this same rapid fire flapping motion, followed by quick glides.
While on the subject of convergent evolution, there are other examples in the bird world that demonstrate how species of different evolutionary lineages nonetheless evolve the same physical traits. For instance, have you ever noticed that birds who inhabit flat areas, such as meadows, parks, beaches and construction sites develop white edging on their tail feathers? Meadowlarks have this, as do Pipits and Horned Larks, all birds that forage in wide open areas. I wonder if this white edging along the tail feathers breaks up their silhouette and helps them disappear into the landscape, so that they are not so easily spotted by predators flying overhead.
Life is full of wonders like this to observe and ponder, if we take the time to observe and ponder. So the next time you are playing tennis at night, look up! Don't worry - your name is not Serena and this is not Wimbledon, so if the ball misses your racket and hits you in the belly while you are marveling at the fluttering Nighthawks, no one is going to care.
Get this cool Lesser Nighthawk puzzle on Amazon!
Birds by Mel is powered for flight by copious amounts of shade grown, warbler friendly coffee, which unfortunately is very expensive. I have nothing to do with ad selection here, but unless you find them completely annoying or offensive I would appreciate if you investigated what my sponsors have to say.
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