Return of the red squirrel after devastating virus
Rare red squirrels are slowly starting to repopulate Tollymore Forest Park after they were nearly wiped out by the squirrel pox virus last year.
Some 90% of the Co Down forest park’s red squirrels died after the disease — transmitted by grey squirrels — swept through the population in 2011.
But the last case of the disease, known as adenovirus, was detected one year ago and it is thought the animals are very slowly starting to repopulate.
Agriculture Minister Michelle O’Neill said the re-emergence of young red squirrels at the Forest Park near Newcastle, coupled with the fact that the last observation of a red squirrel showing symptoms was reported over a year ago, provides optimism that the population is recovering.
Responding to an Assembly Written Question, she said: “The only detected case of adenovirus in a wild red squirrel in the north of Ireland was also confirmed in Tollymore Forest in October 2011.
“No further cases of the adenovirus occurring within a wild red squirrel population have been reported in the north of Ireland since.”
However, the recovery has remained sluggish, with low numbers of squirrels this year, according to Northern Ireland Environment Agency wildlife officer Jon Lees.
He estimates many healthy squirrels in satellite woodlands that could have repopulated the Forest Park were driven into the area by wildfires in May last year and became infected themselves.
“The losses were probably more than Tollymore held to start with. It was a double whammy,” he said.
“It was a dramatic and massive catastrophic failure of the population.”
He says Tollymore Red Squirrel Group estimates that there are now just 10 to 15 red squirrels left in Tollymore, with five or six in satellite woodlands.
“The population has been fairly hard hit but, with the continued work of the red squirrel group and Tollymore Forest Park to control greys and supplement feeding, we hope to get the population back up again,” he said.
Another outbreak of the virus was reported in the Glenarm area in July last year. Both areas have very active red squirrel groups, suggesting that there may have been outbreaks elsewhere in Northern Ireland that simply went undetected. Grey squirrels are carriers of the disease, showing few of the symptoms themselves, but once infected a red squirrel will succumb within around 14 days.
The non-native greys will also out-compete red squirrels in any area where they are both present, pushing them closer to the brink of extinction.
Experts are calling on members of the public to alert them if they see a red squirrel, as Red Squirrel Week kicks off (October 2 to 9).
For further information on the red squirrel contact your local red squirrel group or Rachel Bain, Biodiversity Officer, at firstname.lastname@example.org.
The red squirrel is believed to have been present in Ireland since the end of the last Ice Age. In the 1700s it is thought to have become extinct in Ireland. In the early 1800s, red squirrels were reintroduced. The population continued to increase, then declined rapidly across the British Isles — possibly due to disease.