Recent data including the All-Ireland Squirrel Survey 2019, and Ulster Wildlife’s Squirrel and Pine Marten Survey 2020, indicate that across Ireland, red squirrel range is increasing and grey squirrel range is contracting. Ulster Wildlife are committed to ongoing monitoring and are in the process of carrying out their 2022 survey. The tide is thankfully turning for red squirrel conservation: heightened public awareness, constant vigilance and the tireless efforts of volunteers, alongside the re-colonisation of the pine marten, have all played a role in the red squirrel resurgence.

However, it is vital to avoid complacency. As long as the invasive American grey squirrel remains, there is always a threat to red squirrels in Ireland. Along with competition from greys, one of the major threats is from Squirrel pox. 

This Red Squirrel Awareness Week we wanted to highlight the effects this disease can have on our native reds. Squirrel pox is a virus that infects and kills red squirrels in a very unpleasant way. Both red squirrels and grey squirrels can carry the virus, however in grey squirrels the virus is asymptomatic and they are not adversely affected.

Grey squirrels, though immune to the virus, can pass it onto red squirrels. The virus spreads through contact with an infected host and also through faeces, urine and salvia. The Squirrel pox virus is very robust and can survive without a host for up to a month. If animals of the two different species inhabit the same territory and feed in the same areas, it is highly likely that transmission will occur.

In red squirrels, the symptoms are very severe. Initially squirrels will become more lethargic and often less wary of humans and predators. They will then develop swelling around the eyes and mouth, eventually developing into sores and lesions that can often cover the animal’s whole head. They will slowly weaken until they perish. Squirrel pox symptoms are often described as not unlike Myxomatosis in rabbits. Squirrel pox can spread rapidly, and a small population of red squirrels can succumb to it very quickly.

The first confirmed case of Squirrel pox in Northern Ireland was in 2011, but it is likely that it went undetected long before that. Last year a site that had been monitored by the North Down Red Squirrel and Pine Marten Group unfortunately had an outbreak of pox.

Alan Bates from the group said, “In Clandeboye, until last year we had a small community of red squirrels. We noticed on our cameras an incursion of grey squirrels and shortly after, one of our reds appeared on camera with swelling on its face and fingers. We immediately shut down the feeders and set about trapping the greys, but it was too late. Another red squirrel appeared on camera with suspected pox. Within a couple of months, we were down to just two red squirrels. They are now dead too.”

This is a very unfortunate situation and shows the impact grey squirrels can have on our small and isolated populations of reds.

One of the best ways to prevent any disease is to prevent transmission, and so disinfecting feeding areas for squirrels is extremely important. If squirrels are using a feeder, either a squirrel or a bird feeder, regularly disinfect them to prevent the spread of squirrel pox. Do not move food from one feeder to another. If red and grey squirrels are observed at the same feeder, stop feeding the area immediately to reduce the chance of transmission. In areas with Squirrel pox outbreaks, feeder stations should be removed altogether. For further information, refer to the Northern Ireland Squirrel Forum’s guidance on feeding and hygiene.

If you think a squirrel has Squirrel pox, contact: Squirrels@daera-ni.gov.uk.

Ulster Wildlife has been working on red squirrel conservation for a number of years and we believe a continued collaborative approach is necessary. We believe there are a number of factors which need to be addressed in order to allow red squirrels to thrive and continue to spread. Alongside disease control and grey squirrel management, monitoring, research, education and awareness, as well as habitat protection, creation and connectivity, are all vital in order to make sure red squirrels are around for generations to come.

If you want to read more about red squirrels in Northern Ireland and what we are doing to help them, you can read our 10-year Conservation Strategy for the species here. 

If you have seen a red squirrel, grey squirrel or pine marten – please report it to our new sightings database: ulsterwildlife.org/red-squirrels