OFTEN it can be quite subjective or a matter of opinion, what we deem to like and appreciate and what we might otherwise take quite a dislike to, writes Roy Bamford.

Just now I have it in for grey squirrels and American mink amongst a range of other things in the environment: plastics are certainly high on that list (and growing) along with a whole lot of other human rubbish, but most of the other dislikes are plants.

Invasive Non-Native Species (INNS), however introduced by human activity, should not be here and the reason they can be so invasive is that their natural controls are usually lacking.

The release of mink (Mustella vison) from fur farms by animal rights activists was clearly a big mistake. The introduction of grey squirrels from the 1870s in to the early 20th century has been disastrous.

I have also been involved in a lot of water vole work. This brings in the American mink, a distant mustelid cousin of our stoat, weasel, otter and even the badger.

As a youngster I can remember water voles as widespread and in many instances quite common. At Cors Caron the water vole population has recently crashed and it is almost certainly due to an increase in the mink population.

There are schemes already in place to control grey squirrels in parts of Ceredigion and also proposals to monitor and possibly control American mink around the Cors Caron area with a view to aiding the recovery of the water vole.

This is good news for the native wildlife of the area.

Good news, from the Vincent Wildlife Trust, may be in the form of the release of 20 pine martens in the Rheidol Valley last September.

Maybe the bonus will be their effect on grey squirrels. Anecdotal evidence from the Republic of Ireland indicates that where martens move in, then grey squirrels move out.

Apparently red squirrels are relatively unaffected but I remain to be convinced of that and it remains to be seen how effective this reintroduction might be.

Personally I can’t wait for a pine marten to appear in the garden here, and start sorting out the grey squirrels. We shall see.

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