Red squirrel population under threat from virus

Wildlife experts have warned that it is only a matter of time before a lethal virus that could wipe out the red squirrel population is detected here. Squirrel poxvirus is spreading so fast in Britain that researchers say some populations may die out completely within 10 years.

The virus has not been detected here yet, but researchers have identified squirrel poxvirus antibodies in grey squirrels in Northern Ireland. The disease is carried by grey squirrels but doesn't appear to affect them. There is no known antidote for the virus which usually causes death within two weeks. Visible symptoms include lesions and pustules around the eyes, mouth and feet.

Dr Colin Lawton, at the Department of Zoology in NUI Galway, said this was a further blow to the red squirrel which was already under siege from the grey.

"It seems that it's only a matter of time before it is picked up here," he said.

Dr Lawton said there were about 50,000 red squirrels in the State, compared with 250,000 greys. The red squirrel population had continued to fall as the grey population increased in recent years, he said.

The grey squirrels were outcompeting the reds for food and an outbreak of this disease would speed up that process. "When the virus is present, grey squirrels will replace the red squirrels at least 13 times faster."

The Irish Wildlife Trust said the virus had the potential to make red squirrels extinct here. "It would be detrimental to the red squirrel population," said Sarah Fields, development officer with the trust. She said the red squirrel population was already in serious decline. Reds usually vanished from broadleaved woodlands within five to 20 years of greys moving in, she said. Greys are more robust in fighting for food, they are prolific breeders, and they come out from hibernation earlier.

Dr Lawton said it was important to monitor the situation and to discuss best practice in the event of an outbreak. A spokesman for the Department of the Environment said it was monitoring the situation and was aware of the threat to the red squirrel population. He said a species action plan to protect the red squirrel was now being prepared and would be published before the end of the year. It will look at issues such as culling grey squirrels and moving red squirrels to more favourable habitats.