2023-08-10 08:17:00
Swifts migrate over and away, to Africa. As they promised spring in April, they are now announcing autumn. But for the time being they will continue for a while, because before the whole of Northern and Western Europe is empty, we will be a few weeks further. And until October, a wandering swift or a griffon swift that has strayed from Spain can show up.
Noticing swifts flying by is not as easy as it seems. The birds do not howl through the streets, but rush past quite high in their fast train speed. The whole of the Netherlands has passed in half a day. Swifts only want to stay there for a while if there are many insects hanging around somewhere above a flower field or freshwater pond on a late summer day. Then there are often real swallows: house, barn and sand swallows. The last three only leave at the end of September and the beginning of October.
Swifts, as almost everyone knows, are not swallows. They are not even songbirds. They are standing… excuse me flying (swifts can’t stand) closer to the hummingbirds than to the songbirds. The vultures migrate to tropical Africa, where they spend the winter above the rainforests of Central and West Africa. There they share the airspace with African swift species. Swifts are one of, if not the fastest fliers in the animal world.
They can go faster than 100 kilometers per hour, not by dropping like a torpedo, but really on wing power. Their body is well streamlined, which is now called aerodynamic. The curve and pointiness of their wings are both geared towards speed. Swifts therefore fly to France in a turn of their wings.
Flying is their life; they do everything flying, even sleeping and mating. They do hang on walls and hatch their eggs in May, but otherwise: flies! On the ground, they are helpless and unable to rise again, so they can fall prey to a cat.
Three times a week, biologist Koos Dijksterhuis writes about something that grows or blooms. Read his previous Nature Diaries here.
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