FLANDERS MOSS is one of those national nature reserves with a car park, a well-made circular path, an observation tower, a couple of judiciously sited benches, and a series of interpretation boards that depict and spell out some of the peculiarities of the mysterious denizens of Europe’s largest raised bog. It’s a claim to fame of a kind.

So you will be introduced to the world of toads, frogs, newts, water-bugs (not an actual species but a generic term I have just made up to hide my ignorance of water-bugs), dragonflies, damselflies, dragonfly-and-damselfly-slaying birds (tree pipits, reed buntings and redstarts, for example), drumming snipe, piping curlews, mosses and water-loving plants, winter geese and whooper swans and short-eared owls and woodcock, a day-flying moth (the argent and sable) and a moth with no wings (the female Rannoch brindled beauty), vagrant otters using man-made ditches to travel between watersheets, red deer and roe deer. But they make no mention at all of the common gulls and the foxes.

I am not an enthusiast for countryside “interpretation”. The very word seems to me to imply, “you don’t know what we know so we’re telling you a little bit of what we know in simple words we think you will understand, and we’ll tell you some of what you should be looking for but not anything so important we have to keep it a secret from you”. But at Flanders Moss, at least the touch is light, the language is unpatronising and avoids the much-loved tendency of nature interpretation board writers to use tabloid-esque jokiness lest you might be under the mistaken impression that nature is important. The path is well-made and evolves into a well-made boardwalk that lets you look at the raised bog and its unique wetland community in the eye without stepping up to your waist in glaur or simply disappearing into it forever. But the signs still don’t mention the common gulls or the foxes.

So this is what the signs don’t tell you. The common gulls turned up one afternoon in early February, a small advance party of eight, speculative nesters I guessed, having drifted far inland via the Firth of Forth, Stirling, and the broad plain of the Carse of Stirling, above which lies the Moss. I say above, I mean about twenty feet above. It is noticeable as soon as you leave the car park (which is at the same level as the fields of the Carse) that a short path rises up at once through a strip of handsome birch wood before it bursts into the wide-open, level sprawl of the Moss, which you now see lies like a glorified mezzanine of nature slung between the Carse and the foothills of the Highlands. Beyond these, an arc of mountains from Ben Lomond in the west to Stuc a’ Chroin in the north scrawls across the sky the unambiguous signature of the Highlands. The next piece of flat country is Rannoch Moor, fifty miles further north, 1,500 feet higher than this, and as resolutely Highland as the Moss is Lowland.

So it was into this wide waterworld that the gulls wandered and it was there that I met them that February afternoon, watched them drift low over the Moss, circle twice on gliding wings, then land on one of the Moss’s countless pools, the nearest one, as it happened, to one of the benches where from time to time I like to sit and write and look around at the wild world between sentences.

At first I was wary of disturbing the birds, but after a few days of afternoon visits to the bench they treated me with indifference and I could watch them and photograph them and write them down at my leisure. And then there were six.

My first thought was that they had just moved on. It happens. Then one late afternoon, just as the light was going and I was taking my leave, I saw a dog in the distance on the footpath. It’s not unusual. People like the easy nature of the path, the beauty of the surroundings, and they bring their dogs with them. Two things made me wonder about this particular dog: one was that it was an odd time of day to walk a dog out here, just as it was getting dark, and the other was that it did not appear to have a human accomplice. So I had a quick look with the binoculars and what snapped into focus was a dog fox.

I was a long way from the gulls’ pool and heading further away, and towards the birch wood and the car park. The fox was coming the other way, and loping along the boardwalk as if it had been provided for foxes rather than people and their dogs. I found a relatively dry patch of ground beside the boardwalk, stepped off carefully, and tested every step of the few yards to a sapling birch a little less tall than I am, and stood behind it. In summer its leaves would have screened almost all of me, in February its skinny branches might just help to break up my shape in the eyes of the fox if he wasn’t in a particularly noticing mood. It was a forlorn hope, for the fox is the most noticing mammal in all of wild (and wolfless) Scotland. Besides, he would find my scent waiting for him as soon as he drew level with the birch, and if anything his awareness of scent outsmarts his awareness of sight.

He duly arrived without breaking stride. I could hear the rhythmic patter of his feet on the boardwalk. About twenty yards away he looked straight at me. His stride never faltered and he walked straight past but his eyes never left me until he had gone a dozen yards further along the boardwalk. Then he stopped, turned and stared at me for several seconds, and then he turned and walked on, resuming the same resolute pace as before. I watched him fade into the gloaming, as I have watched so many foxes fade into so many different landscapes. And two days later there were four gulls, and I began then to put two and two together and make four fox meals of the ones that had disappeared.

Nothing changed until early April, and although I made several afternoon visits that lingered until almost darkness I didn’t see the fox again. The gulls were settled and apparently untroubled on the same pool. And then there were two.

And then I walked out one bright spring afternoon that was giddy with skylarks and tree pipits. Halfway to the bench by the pool, one of the gulls rose and came straight towards me, circled low overhead calling loudly in tones that said “piss off ” in any of the languages of nature. I walked on until I could see the pool, and there in the binoculars was the head of a sitting bird deep in a bush of thick reedy grasses. I wished them good luck, and headed for the far side of the reserve, and there on the path I found two fox scats.

I settled down to wait for the dusk. The denouement came while there was still just enough light in the west to see clearly anything that crossed that patch of sky. There was a sudden clamour of frenzied bird cries. I looked up to see both gulls low over their territory, and I headed for the pool. I was still a hundred yards away when the commotion reached fever pitch and both gulls were constantly diving down towards their pool, screeching as they dived.

The fox was wet when I saw him, wet from his short swim to the nest, and my best guess is at he had just cleaned out the nest of its eggs then swum ashore again. He cut away across the bog, not putting a single foot wrong amid so much underfoot treachery, an angled run that met the path a few yards further on. There he stopped once more and looked back at me in a perfect reprise of the attitude with which he had studied me behind the small birch tree. Then he looked back at the pool with its hapless gulls still circling, still crying. Then he turned and trotted off back towards the birch wood.

The next time I visited the Moss, there were no gulls, and whether they too succumbed to the fox as they tried to nest again, or whether they had simply given up and moved on, I have no way of knowing. They must have thought that their deep pool with its tiny, densely-grown grass islands was a perfect nest site, but they were not the first and they will be far from the last creatures to underestimate the ingenuity of foxes. It is easy to take sides in circumstances like these, and there are those who will consider it inhuman not to. But it is nature’s way that prevails here, and nature has endowed the fox with many uncanny survival skills, only one of which is that of an enthusiastic swimmer. The fate of the common gulls of Flanders Moss is just the way it is sometimes. You and I, being members of the one species that has shown more vicious animosity towards the fox than all the predators of nature combined… you and I have no right to judge.