With their forked tails and scythe-shaped wings, swifts herald the arrival of spring in Europe and are seen as the bringers of rain in parts of Africa where they spend their winters. These amazing birds spend almost their entire lives in flight, so much so that their legs are small and too weak to support them for long when perching, explaining why their family name, Apodidae, is taken from the Greek word meaning ‘without feet’. Spine-tailed swifts, also known as white-throated needletails, have been measured as flying up to speeds of 105 mph (169km/h), while common swifts are known to routinely reach speeds of 70 mph (112 km/h).
Although they resemble swallows, swifts are placed in the same order as hummingbirds, Apodiformes, while swallows are of the order Passeriformes. Their similarities are attributed to convergent evolution, a phenomena where differing species develop similar traits due to lifestyle adaptations, in this case their habit of catching insects in flight.
Distances are immaterial to swifts, as they can easily fly 500 miles in a day. Most swifts remain airborne from when they fledge to the first time they breed – a period of roughly four years. It’s been estimated that in a swift’s lifetime it will cover a distance of around 1.28 million miles. They even roost on the wing, circling gently for hours as the two sides of their brains take turns in sleeping. Swifts only nest to raise their young, and are fond of doing so inside roofs of houses. Parents can gather and carry as many as 1,000 insects to feed their young, making them very effective insect controllers. When the fledglings leave the nest, they all take to the skies and so the cycle continues.
When swifts are feeding in the late afternoon, they swoop through the air in a series of aerobatics that are fascinating to watch. As is the case with hummingbirds, swifts are able to rotate their wings in a manner that keeps them fully extended and rigid, delivering power on both the upstroke and downstroke, thereby increasing their speed and maneuverability. No other bird species are able to do this. So if you happen to have the good fortune to see swifts in action, take some time to appreciate their unique characteristics.
International Dawn Chorus Day is the worldwide celebration of nature’s daily miracle. This year there will be more opportunities than ever to join in the excitement. In the run up to the event events from all over the world and across the UK will be listed on www.idcd.info/ so visit regularly to see what’s planned in your area.
Celebrated on the first Sunday of May, the story goes that International Dawn Chorus Day began in the 1980s when broadcaster and environmentalist Chris Baines asked everyone to attend his birthday party at 4am so they could enjoy the dawn chorus with him. Since then IDCD has grown from a small event in Birmingham UK to an annual international celebration with Dawn Chorus events held as far afield as the Caribbean and Antarctica.
Date: 3 May 2015
Venue: Visit www.idcd.info/events/ for information on venues.