Once the gameshooting season is over, the weather is cold and the woodland canopies are bare, it?s the ideal time to get to grips with your grey squirrel population. Some may find this tree-dwelling rodent appealing, but its crimes include stripping bark, stealing eggs and young chicks, and carrying the squirrel pox virus which has largely wiped out the native red squirrel. It also loves to chew most things, causing considerable damage to hoppers, water pipes and feed bins ? not one plastic seat or foam-covered shooting bar among my high seats has escaped their attention. Controlling numbers is essential. A recent report suggests that the damage they cause costs the UK economy about £14million every year.

Nest hunting

There are a number of ways to reduce grey squirrel numbers, but catching them at home in their nests, or dreys, is a useful part of a wider campaign. The footballsized dreys are constructed of twigs and lined with moss, grass, bark and other materials to create a safe, warm refuge. One squirrel may build several, but during the winter they are often shared for warmth. The result can be a veritable explosion of squirrels when an occupied drey is disturbed.

In addition to providing a practical session on pest control, I like to use drey poking to assess my gamekeeping students in shotgun handling and safety. It?s all very well learning to use a shotgun under the controlled conditions of a clayshooting ground, but there?s no substitute for the unpredictability of a session in the woods.

Inevitably, I?m asked why we don?t simply shoot a drey out, as it?s much quicker than poking with poles. There are several reasons. Perhaps most importantly, other creatures may use an unoccupied drey ? tawny owls in particular ? and it?s vital to avoid shooting a non-target species. Second you never really know if you have killed or just wounded anything inside it. Finally, unless you destroy the drey properly then it?s still there as a refuge ? and even if it?s beyond repair a future session may waste time dealing with it unnecessarily.

Practical session

As we left Sparsholt it was unseasonably warm meaning our chances of finding many squirrels at home were low. Subzero temperatures and a good fall of snow, which reduces opportunities for foraging on the ground, are more likely to keep the quarry in their nests. Wet and windy days can also be productive. Nevertheless, there was an air of optimism among the students. First, they were delighted to be out of college for a practical session and, more significantly, none of them had experienced drey poking before.

We started with the usual risk assessment and safety brief. You only need four people to do the job effectively ? two to shoot and two to work the poles. As we were a larger party, setting the ground rules was doubly important. Those doing the shooting were instructed not to fire below an angle of 45°, and to take nothing on the ground.

Quite apart from loaded shotguns, everyone had to be aware of the hazards involved in working with poles, which might be extended as high as 48ft. Steel toe-capped boots and chainsaw helmets, with their built-in visors and ear defenders, were the order of the day for the pole men. A fully extended pole is heavy, and dislodged drey debris is a hazard in itself when you are standing directly underneath and looking up.

Finding the first

We set off in search of our first. Mole, my spaniel, was an enthusiastic if imperfect squirrel dog. She ensured that any squirrel on the ground would prefer to be up a tree, but in reality an enthusiastic terrier or similar breed is far better suited to dealing with a wounded squirrel than a soft-mouthed gundog.

We found the first drey quickly enough. It looked promising, some 40ft up and tucked against the trunk of a tall beech. Positioning our two Guns well to each side of the tree, the pole men took station below the drey and worked out the best approach to it through the branches. The first three poles, each 6ft long and made of aluminium, handled easily enough when slotted together and clipped firmly with their locks engaged, but soon enough the extending pole started to bend and wobble its way higher and higher. The lads swiftly established that holding it as upright as possible, and using the tree trunk and branches to guide it towards the drey, helped to keep it straight and moving in the right direction as more sections were added. The team leader was a great help, standing off to one side and giving clear instructions to the pole men, who were largely unsighted when it came to obstructions directly above them.

Before the top of the pole had even touched the base of the drey, a squirrel bolted, running along a horizontal branch towards a neighbouring tree. Both Guns fired and the squirrel fell to the ground. There was no need to call off the spaniel as the quarry was stone dead ? an encouraging early success.

Sometimes, squirrels will sit tight and need a bit of persuading to leave their nests. This is when the head of the pole needs to be worked well into the drey in order to give a little bit of encouragement. The Guns stood by expectantly as the pole men worked the drey, but soon it was apparent that this animal had been alone.

The job wasn?t over yet, though, as the structure had still to be broken up. Here the T-piece at the head of the pole could be used to hook into the bundle of twigs to drag the drey out of the tree. Like every drey poker before them, the pole men learned soon that it?s best to keep your visor down and your eyes averted.

With the nest cleared, the pole was taken apart and we went in search of the next. The whole operation had taken about 20 minutes or so ? not bad for a first attempt.

Over the course of the morning we accounted for more than 20 dreys, most of which were unoccupied, but a number of squirrels were found and killed. Sadly, there had been none of the excitement you get when multiple animals decide to depart in all directions, but that was not the aim of the exercise. I was pleased to see that gun handling was safe and accurate, that everyone had had a chance to learn how to use the poles and that there had been some first-class teamwork. Just as importantly, we had a satisfied local gamekeeper with one less job to do on top of a busy schedule.

Charles Smith-Jones is a lecturer in game and wildlife management at Sparsholt College, Hampshire.