The sound of summer in the UK surely has to be the screaming of swifts, Apus apus of the Apodidae family. You can play an audio file on the RSPB site.
They are unrelated to swallows, although they look similar. Swifts are in fact more closely related to hummingbirds. They are usually just black specks high in the sky, they have shorter forked tails than swallows. If you ever manage to get close to one they are a sooty brown with a little white patch on the throat. They can fly up to 10,000 feet; 3,048 meters and they feed, preen, mate and even sleep on the wing.
Having such aeronautical prowess makes them uncommon hard to photograph! They are on the wing all day hunting insects, they do not perch due to their tiny weak legs and feet. They are highly manoeuvrable and very … well … swift – reaching speeds around 112 kmh; 70 mph. At the end of summer as insects become more scarce, UK swifts migrate across Europe and over the Sahara to winter in Africa. One tagged swift was recorded as having made the 5,000 km; 3107 mile trip from West Africa to the UK in just 5 days.
Swifts are rapidly declining from the UK. It has been estimated that a third have been lost since 1995. If you see and hear them circling and screaming low over roof tops it suggests that they are nesting nearby, the RSPB is asking that you submit such sightings here.It is thought that their decline may be linked to a lack of nesting places. They evolved to nest in caves, but followed humans into cities and nested under the eaves of our houses, but many modern houses do not have suitable nesting spots. If you wish to encourage swifts and provide much needed nesting places for them you can purchase “swift bricks“.
Once dusk falls, the swifts circle lower and lower, their screaming louder, until they disappear into their roosts. Then it is time for the night flying insects and their predators the bats to own the night sky. These are even more difficult to photograph!