The photograph shows an adult swift that was found grounded and helpless.

If a swift accidentally falls to the ground, something which is very rare, then its scimitar-shaped wings and virtually useless stubby legs prevent it taking off again.

Fortunately a passer-by found the bird and took it to the RSPCA in Putney.

From there, it was taken to the open meadow on Wimbledon common for release.

We watched as the young lady handler gently and expertly took the swift from a box and waiting for a gentle breeze, launched it up into the air.

Momentarily the bird's flight faltered and it almost stalled so we feared it might plunge to earth but it recovered rapidly and soared up into the blue where it was joined by another swift and the pair flew over the tree belt and were lost to view.

That swift and indeed the whole population (sadly much reduced this year) will leave our shores in early August and fly back to South Africa where they will remain continually airborne until returning to us next May to breed.

Even then, the young non-breeders may stay aloft for up to three years before finally resting on their nest.

Watching that swift being released was truly a magical and heart-warming experience.