FOR the past 30 summers, I have enjoyed watching swallows as they nest beneath Turks pier alongside the river Thames at Kingston. This year there are three nests and I'm here on a sunny afternoon in late May watching three sets of parents hunting in pairs as they speed up and down the river, scooping up mayflies emerging from the surface then at full speed, zooming up into the nests under the boardwalk to be greeted by a loud chorus of twittering youngsters eager to be fed. A truly magical display of precision aerobatics.

After spending our winter six thousand miles away among extensive reed beds around Cape town in South Africa, the swallows fly back here, the males first to re-establish old territories or search for new nest sites, followed by the females a week or two later.

Nature Notes: The delight of birdsong

All the birds are sporting fresh plumage reminding me of mini Union Jacks with blue, red and white plumage. Nests are built only a metre or so above the water so when the youngsters first leave their nests, and considering they have never flown before, they must perform an extremely skilful yet risky manoeuvre to ensure they don't flop into the river. Hopefully they all survive their perilous exit.

Normally two broods are raised each year but in a warm summer they may manage three.