A PIERCING whistle followed by a bolt of electric-blue as the kingfisher shot along the course of the River Devon near Tillicoultry.

Flying with the surety of a guided missile, it rounded a bend in the river and was gone.

It was all over so quickly that I questioned whether I had actually seen anything at all. Could that flash of cobalt been just a figment of my imagination?

Well, no, the blue-blurred form was real enough, for that is the way with kingfishers, given that they are such flighty birds, quick to take to the air and whooshing low over the water with verve and determination.

Indeed, it is unusual to ever get a close and clear view of a sitting bird, such is their skittishness.

Kingfishers are doing well on the River Devon at the moment with birds present from Dollar and all the way downstream to Cambus.

The next few months will prove challenging for them because they are vulnerable to cold winters and numbers will plummet if there is a big freeze.

Their populations do, however, tend to quickly bounce back as they have two or more broods in a season.

The Devon is a spate river and the recent heavy rain has at times raised the water levels and turned the water an impenetrable muddy brown.

I used to wonder how kingfishers hunted for small fish such as minnows and sticklebacks during these periods when the river lacks clarity.

But by watching their behaviour over the years, I have found the answer.

During such times, they hang around the numerous backwashes, creeks and ditches that feed into the main river.

The water remains remarkably clear in these places, even after heavy rain, and small fish are abundant because they are sheltered from the surging torrents of the main river.

By using such guile, our kingfishers can survive heavy spates, and in the process bring a welcome splash of colour to the Devon.

The kingfisher is a true river halcyon, and no matter how brief the encounter, that wonderful zipping streak of blue will always linger long in the mind.