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Each swallow species uses airspace differently By Stewart Janes Jul 22, 2022 12:15 AM A A Barn swallows are the only swallows with long, forked “swallow tails.” [123RF.com photo] “One swallow doesn’t make a spring.” I don’t know who coined the saying, but it wasn’t me. From the middle of January on, I watch the skies carefully for those early signs of spring. Some years swallows arrive by the 20th of January. In others, I must wait until late February. Swallows arrive at a time when the valley is gearing up for spring. Flowers are blooming, and nest building by some of our resident birds is underway. So yes, one swallow marks the official start of spring, at least for me. The first to arrive is the tree swallow, soon followed by the violet-green swallow. It’s great when the skies begin to fill again after a winter of little more than ravens. Don’t get me wrong: I have great affection and respect for ravens, but they cannot dance in the sky like swallows. Soon after the violet-greens, the rough-winged, cliff and barn swallows add their numbers to the mix. Although not a swallow, the Vaux’s swift adds its voice and acrobatics to the aerial party by late April. If you have spent as much time as I have daydreaming and following this show, you realize each uses airspace in its own way. Violet-green swallows are the generalists. They fly mostly above the treetops and on up a few hundred feet. Here there is a clear view of the flying insects, and the density is relatively high. Insects rise high from below seeking mates, dispersing or whatever else they do. Good hunting for violet-green swallows. On average the swifts fly higher. There are fewer insects at greater heights, but they compensate by more rapid flight, thereby covering more real estate. I still wonder how they manage to see and capture insects at the speeds they fly. At the other extreme is the barn swallow. On average they fly lower than our other swallows. If you are birding in the countryside and a swallow flashes by belt-high and barely clears the fence top, it is most likely a barn swallow. In colder weather, they fly even lower with wingtips almost grazing the grass heads or the water of a pond where the few active insects are flying. The barn swallow is our only swallow with a long, forked “swallow tail.” Scientists have wondered whether the long tails provide extra lift aiding in flight. Some say yes. Others say the long tail offers more drag than lift. Whatever the answer to that question, all agree the long tail makes a great rudder, permitting tight turns in close quarters. The long tail of the barn swallow aids them as they fly close to the ground and maneuver around shrubs and other obstacles, enabling them to take advantage of the abundant flying insects that seldom stray far from food and cover. There are several “swallow-tailed” swallows around the world, and all use their long tails in similar fashion. I have watched welcome swallows in Australia fly in and among the legs of cricket players on the pitch, seldom flying higher than 6 inches above the ground. Red-breasted and striped swallows tickle the bellies of wildebeests in the African savanna, and red-rumped swallows inhabit the open areas in southeast Asia. Stewart Janes is a retired biology professor at Southern Oregon University. He can be reached at [email protected].