My first experience of these incredible birds was when I was loading for the late Viscount Bledisloe on a grouse day at Raby Estate in Co Durham. As a low-ground pheasant keeper, the moorland environment was all very new to me, especially the long walk to the butts and the way the anticipation built.

We ended up in butts in peat hags, settled in and got the guns out of their slips. I heard a chuckle in front and one behind and, before long, this comical sound was coming out of the heather all around. I couldn’t help thinking they knew something we didn’t. Then, they zoomed over like Star Wars fighters, their rapid wing beats whirring as they weaved in and out of the hags. There was much banging and passing of guns, then quiet, and then the chuckling started again.

Now, as I look out over the moor that I, and a team of four keepers, manage in Dumfriesshire, there’s no more idyllic place. Bathed in sunshine, the bright white heads of cotton grass would resemble patches of snow were it not for the pink flower of cross-leaved heath and the mauve of the bell heather. The lush green new heather is forming into flower spikes and will soon be the mass of purple that signals the start of the grouse season on the Glorious Twelfth.

However, look carefully at the old heather and you’ll see that much of it has been burnt off by the severe cold and winds of the long winter. Remarkably, Lagopus lagopus scotica manage thrives through all these glorious and not so glorious conditions when moorland is managed. In July, we start to count the grouse, when the young are almost the same size as the adults-eight weeks since they were an egg. Red grouse are good parents; the cock proudly guards his territory, having won it in spring, with a vertical take-off and parachuting descent.

He stands guard over his nesting hen, emitting a slow, guttural clock, clock, clock call as a warning if he spots anything amiss. Prior to nesting, the hen becomes very secretive and can be heard chatting away as she and the cock feast on the buds of cotton grass, known as moss crop, which gets her in good condition to lay her eggs.

Once the nest has been created in longer heather, her camouflage plumage (lighter and more golden than the cock’s reddish-brown feathers and bright-red wattles) comes into its own, as, there, she will sit tight for 23 days after her clutch-seven to 12 eggs-is laid.

During incubation, the hen sits motionless, and her heart rate falls in a bid to make her less detectable by predators-scientists believe that healthy birds give off very little scent. She will leave the nest twice a day to relieve herself, with one almighty ‘clocker’ dropping (think consti-pation), and a quick feed some way from the nest.

All the time she’s absent from her precious eggs, she remains vigilant to the intrusion of a raptor or corvid. These avian predators are extremely observant and spatially aware-if there’s any chance of regular meals, they will return.

Once the eggs hatch, the chicks have their yolk-sac packed lunch to keep them going for 24 hours. After that, they have to follow mum and feed themselves. She will lead them to places she thinks are rich in chick food. Invertebrates are the best source of protein, but red grouse can quickly glean nourishment from plant material, which is why new nutritious heather shoots are so important, because they are soft and accessible. As the cock and the hen usher their brood, the hen is easily identified by her anxiously extended neck as she looks out for danger.

Compared with other game chicks, grouse are tough little nuts. Their large, white, feathery feet-which are obvious from hatching time-enable them to navigate obstacles easily. The distance over which they spread out and feed away from their parents is astonishing, yet mum and dad are always on hand, constantly communicating with sounds and calls.

If a predator or a human gets too close for comfort, the hen does her wing down, tail-shaking routine to lure you away from her brood; the chicks freeze and bury themselves in dense vegetation. When we’re catching chicks (with pointers) to check for ticks, we often don’t find the entire brood-you think there are six chicks, but, the next time you look, there are eight.

Once the threat has passed, the adults return, calling the brood back together, and off they go again, rambling over mounds and tussocks and pecking at every edible-looking morsel.

Spring and summer on a moor can be harsh, yet the grouse, a sub-Arctic bird, can cope with all sorts of conditions, although chicks and poults will succumb to persistent wet. Small chicks of about two weeks of age are not fully feathered and sometimes can’t all be brooded by the hen. However, that perilous 12 weeks soon passes, and the birds that make it are usually fit and strong, although many have some unwanted visitors on board, such as tapeworm and strongyle worm.

These parasites are, despite the use of medicated grit (which grouse take on to grind up some of the tougher plant material they eat), still part of the grouse’s lifecycle. Indeed, the deadly strongyle worm has long been responsible for the boom and bust cycles of grouse populations. This is what makes grouse-shooting so unpredictable and, therefore, exciting and valuable.

The birds roost at night, jugged down in the heather, or sometimes on open, freshly burnt fire sites. Despite the exposed nature of heather moorland, grouse will thrive provided predators don’t gobble them up. In winter, they may have to dig themselves out of deep snow and, if the drifts are too heavy for them to get to the heather, will move miles from their home ranges to find food.

During the last couple of severe winters, there were reports of grouse travelling to the coast in search of warmer climes, and even feeding in trees. Then, these true survivors return to the moor to continue their remarkable existence.

How to age grouse

If you’re lucky enough to shoot grouse this season, here’s how you can tell a young bird (which will make better eating) from an old one

Toenails Look at the length; an older bird will have a ridge along its nails, whereas a younger one’s are smooth

Beak It’s possible to bend that of a younger bird. The skull is softer, too-you should be able to press your thumb into the head of a juvenile bird

Wing feathers Study the long, primary feathers. Those on a young bird are pointed, but on an older bird, they’re worn and rounded, shaped like the end of your finger

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