Don't let greys make April fools of you

As the weather warms up and trees come into leaf, grey squirrels will be looking for drey sites — now is the time to get them

- Liam Bell

Grey squirrels are a destructive, invasive, non-native species. The damage they do to our native hardwoods, when the trees are between 15 and 25 years old and at their most vulnerable, is well documented, as is their predation of the nests of woodland birds. These are reasons enough to control them, before we add in the fact that they are responsible for the demise of our native red squirrels. They will also damage feeders and drinkers and are happy to spend their days chewing holes in the alkathene water pipes in our pens.

April is the month to get on top of them, when the weather is warming up and they are starting to move between the warmer woods, where they will have spent most of the winter, and the as-yet bare hardwoods to look for food and drey sites. Make a dent in them now and there will be fewer youngsters to strip the bark off the trees in July and August. This is when most of the damage is done.

Grey squirrels can be shot and trapped. Those are the only options available to us at the moment — although advances are being made in the development of an immunocontraceptive that could render the adults infertile. Shooting works if it is sustained and coordinated. Trapping works if it is timed and targeted. What works best is a combination of the two. In an ideal world we would be able to get rid of greys completely, but in reality any removal is only temporary as there are always animals coming in from areas where they are not controlled.