Here comes a young buck of inferior build, smaller, lighter, with only bumps of antlers. He is the one to get

Six-forty am. The sky is blazing with stars, but the eastern horizon has only just started to glow. There is time to stand and listen.

An icy breath of wind steals out of the north, too gentle to mask any sound. A tawny owl hoots, and suddenly there it is: the heavy, snoring grunt of a fallow buck on his rutting stand, deep in the wooded valley to my left.

Snort, snort, snort, snort ... The calls are those of a mature animal, but he is beyond the boundary of the land on which I have shooting rights.

That buck falls silent. Then another starts, also below, but on my ground. I can pin-point his position, and quickly plan a route to get to it: across two fields, over a gate into the wood and down a network of grassy tracks, right, left, right.

For a deer-stalker, the main advantage of the rut is that a master buck, by his harsh grunting, attracts animals of every age and shape: not only the does that form his harem, but also lesser bucks, including freaks and cripples - and one of these may well be a good beast to cull.

Nip along this first meadow, then, to a gap in a belt of trees. At the gate I pause and scan the next field with binoculars. The grass glows silver-grey with frost. Two hundred yards out, a deer of some kind is standing in the open, facing me, slim as a ghostly gatepost, but I cannot make out what it is. Above and to my right, beyond a narrow spruce plantation, dawn is setting the horizon on fire.

The second buck calls again. Then from above, much closer, comes a volley, an explosion, of roaring grunts, followed by the rattle of antlers on wood. This sounds more urgent, more promising.

The light strengthens. I look back up the field and find that the gatepost has gone. The commotion on my right is coming from the upper edge of the spruce. I move cautiously in that direction. At the lower side of the wood I crawl under an electric fence and on to a path that I keep raked clear of twigs.

Silently I ease forward up the slope, winding between the spruce trunks. Another outburst of grunts echoes down through the trees, then the sharp crack of antler meeting antler. A fight has started.

Ahead of me the skyline is flaring up red and orange. Across that fiery backdrop flits the silhouette of a deer, a black shape moving fast; then another, and another, all in a state of agitation.

At last I glimpse the cause of the excitement: two big bucks wrestling furiously, outside the wood, in another field; antlers locked, shoving, twisting, they battle for supremacy.

It is a phenomenal sight, this ritual fight etched upon the dawn. If it were rugger training, how happy the coach would be that his lads were getting down so low and bracing themselves so vigorously in the scrum. Steamy breath rises as the combatants shudder, slip and wheel.

Younger deer zip back and forth, black against the light, electrified by the action. A doe and fawn race past, then a pricket (a second-year buck), a good, big youngster, with antlers 8in or 10in long. But then comes another pricket of inferior build, smaller, lighter, with only bumps of antlers. He is the one to get.

I cannot shoot safely from the ground, because the rifle bullet would fly over the crest of the hill. I need to reach the high seat, or tree- ladder, built on the upper edge of the wood, and fire downwards. Yet the seat is barely 20 yards from the battling bucks, and perilously close to the line of the wind. One whiff of my scent, and the whole party will be gone.

I creep on up the path. Ten yards from the field I feel cold air wafting into my face: by a lucky fluke, the wind is curling westwards into the wood and down to meet me.

The assailants break, and as they raise their heads, I can see they are both in their prime, eight or nine years old. Then they set to again with a vicious clash.

At the foot of the ladder I slide the .243 off my shoulder and climb stealthily, one rung at a time. The big boys continue to tussle like lunatics, obsessed with their own affairs, but the mediocre pricket is darting about, hyper-alert. I wait till he is facing away, then wriggle into a firing position 15ft above the ground.

Centre the cross-hairs of the telescopic sight on the animal's neck. BOOM! Down he goes, instantly dead. The two bruisers break contact and stand glaring, as if outraged by the disturbance. Then they gallop away into the sunrise, side by side.

For a second or two there are deer flying in all directions: a moment later, every one has vanished like morning mist.

I feel relieved that everything went well: that I chose the right animal and culled it cleanly. The dead pricket never knew what hit it, and the rest will soon recover from their fright.