The July heatwave provided what I call a 'swift summer'. The long,hot still conditions enabled swifts (pictured) to mop up a bonanza of aerial plankton at a crucial time with fledglings in the nest.

There was no need for parent birds to fly long distances to find food as can occur during inclement weather. So, hopefully, swifts will have reared good numbers of young birds ready to join the adults on their hazardous flight back to Africa, sadly beginning this week.

The same can be said for swallows and martins, all airborne feeders, which will come as a welcome and timely boost to their dwindling populations.

I always miss the screaming cries of swifts when they have departed after such a short time here. In fact, with the summer moult now underway most birds are keeping silent and out of sight. Only my distant songthrush, serenading me since early spring is still singing most days.

One of many fascinating aspects relating to swift's lifestyles concerns the way in which they ascend to roost late on summer evenings, reaching heights of hundreds, probably thousands of feet to sleep on the wing.

Every evening, my local swifts flock together at the same focal point they have used for decades about two hundred metres from my garden. From there, they spiral upwards like a whirling vortex, their cries becoming fainter and fainter as they drift heavenwards.

So, farewell swifts. Hurry back next spring.