The beak is mightier than the rod on the Severn

They duck, bob and then, when prey comes into sight, hover like jump-jets before hitting the water with the precision and ferocity of a depth charge, certain in the knowledge that the target is doomed.

This is the ultimate feathered computer, programmed to lock on to whatever is destined to provide a meal. Whether the water is murky or slightly less than opaque the Severn is never less than weak soup-coloured - this magic bird, the product of Nature drunk in charge of a paintbox and with a wicked sense of humour, never seems to fail.

With the abruptness of the hand in the lake holding Arthur's mythical sword aloft, the kingfisher has propelled itself upwards out of the water and is now back on the branch from where it launched this deadly seek-and-kill mission.

Now begins the method of despatch, the beating of the hapless fish against the branch. Tap, tap, tap... the sound of the silver trophy being drummed into oblivion can he heard by the human fisherman as he watches the orange tip of a motionless float. For apart from a momentary nibble earlier that day, nothing with fins and gills has come remotely near the juicy pellet of Mother's Pride bread paste being offered.

It's a good job this student of Izaak Walton does not rely on the river for his food. For with this level of skill, starvation would soon ensue. Compared to this little chap across the water decked out like the court jester, the technology of rod and line might as well belong to the Stone Age school of fish capture.

Appearances can certainly be deceptive. Who would imagine that someone dressed like that - in a blue and orange morning coat - could possibly have serious intent? But there is no bird quite like the kingfisher, this master of fancy dress who goes about his murder as if attired for a ball. Be warned. This popinjay is no one's fool.

The river is his supermarket, offering all sorts of bargains. Today's special offer seems to be bleak, or skimmers as they are known to those who sally forth with rod and line.

Bleak by name and bleak by existence, every thing about this fish is tainted with doom and the promise of a premature demise. And now, the evidence is all about, especially now that our serial killers have now moved their centre of operations to the sunken boat wedged into the bank on Diglis island just over from the dock.

From the occasional glimpses of carnage taking place, it would be hard to imagine the decks running with more blood at Trafalgar or Jutland. One kingfisher has returned to the boat, and now sits like a pirate captain aboard his beached craft.

The killer bird has another bleak. I can see flashes of silver that tell me that this particular capture is too big. Surely this scaly banquet will defeat even the kingfisher's talent for oral contortions?

The bird seems to be aware that this dinner is slightly bigger than normal, which produces a frenzy of assault and battery. It seems will not be enough to dispose of the unfortunate bleak, for now this larger specimen must be kneaded into something flexible enough to gain passage down the twin-sided harpoon that serves both as the main killing device and food receptacle.

I watch transfixed, my eyes fixed on the crimes taking place on the prow of the sunken boat. Despite the massacre taking place on this sunny afternoon, I remember that when my children were young and we walked by Diglis Lock and over the rickety wooden bridge, I would regale them with tall tales of these skeletal craft.

They were in fact Viking longships sunk long ago in a great battle when the Danes attacked Worcester. The inhabitants had repelled the invaders and those who were not slain and had their skin nailed to the Cathedral door were turned by Old Meg of Diglis into the willow trees that now line the banks of the Severn.

If you don't believe me, look at the willows closely, I would tell the children... can't you see the faces hidden in the bark? There's a pair of eyes, nose and down-turned mouth. And they're always so angry, these gnarled and lined Norse warriors anchored to the banks

But now they are the scene of a different destruction. This is the execution place of a small fish programmed by Nature to swim, with fatal consequences, too near the surface of the river.

There is much going on today down at the water's edge. Activity everywhere except around the few feet surrounding my float now sitting motionless just by the bridge wall. A large chub bursts clean of the water just in front of the weir and hangs for a micro-second in the air, an acrobatic display for the price of a drowned fly.

His domain is mid-river... I delude myself into thinking that he will deign to visit the wall area. Not a hope. The old pin cushion doesn't slum it in this silted-up bay. He's the king of the current, not one of those commoners who must make do with backwater backstreets.

But this is the beginning of autumn and everything is living on borrowed time. The damsel and dragonflies have long ceased to skirt the arrowhead lilies, searching for a meal. They have already savoured their last supper.

I wonder if they knew that despite being granted three long insect years at the bottom of the river as a nymph, their time as the lord of the flies was but a summer.

But now, in damp and misty October, it is well past midnight for our late handsome friend. He never gave a hint of his impending fate, no sign of deterioration or weakness or fading into old age.

Then suddenly, it happens. The float's dipped. Up comes the rod and there's a fish on my line, a golden-flanked rudd. I look across the lagoon, and yes, the kingfishers are still there, sat on their boat. I can almost sense their approval as the fish is placed in the keepnet.

Two turquoise eyes in the distance, surveying their Diglis domain. And just for a moment I had joined them in their trade and we were brothers in arms.