|North Northumberland -big skies and big landscpes|
About 150 years ago grey squirrels were imported into the UK from America as a fashion item to grace the estates of the landed gentry.
The greys store four times as much fat reserve for winter because they evolved to survive much tougher winters in the Eastern USA, they are more prolific and are adapted to living at hgher densities than the reds.So greys have displaced reds throughout much of England and Wales and in recent years have moved north into Northumberland and the Scottish borders..
Bigger, stronger faster breeding greys also carry "squirrel pox" or Parapoxvirus to which they are immune but it is fatal to reds.
The "European Squirrel Initiative" began in 2002 to remove the american aliens from the whole of Europe to protect biodiversity and prevent economic damage to woodland. "Northern Red Squirrels" grew out of this, it coordinates population mapping of both species and control of the greys. www.northernredsquirrels.co.uk
More recently as pine martens have moved south into grey squirrel country it seems that they may be effective and selective predators on greys which feed more on the ground than reds. The reds can move fast high up in the tree canopy on flimsy branches where the pine martens can't follow.