Fears for the safety of the red squirrel population on Anglesey were raised after a red squirrel, shown here, was found dead on the Island with a suspected case of squirrel pox virus. This followed findings of two other red squirrels found dead on the mainland, one in Coed Mor near to the Britannia bridge. Both were confirmed as positive for squirrel pox virus. The virus is usually fatal in red squirrels and if it had spread it could have potential to lead to the elimination of the population on the island. Fortunately, laboratory tests found that the red squirrel found on Anglesey was negative for squirrel pox.
Grey squirrels are carriers of the virus and can spread the disease to red squirrels. Greys, however, have developed immunity to the disease. The concern was that the virus could have spread from the mainland as the squirrels can travel back and forth to and from Anglesey. There is a risk of an outbreak of squirrel pox virus in any red squirrel population in areas where grey squirrels are also present.
In mid-Wales, tests carried out several years ago revealed that squirrel pox virus was present in over 50% of the grey squirrels tested. This is one of the main reasons why all volunteers undertaking red squirrel monitoring in mid-Wales keep a regular check on feeder activity to ensure that grey squirrels are not visiting the same feeders as reds. If greys do visit feeders, the feeders are emptied and disinfected and only re-filled once the grey squirrel threat has been removed.