Return of pine martens could save Britain's red squirrels, say scientists

Areas with growing pine marten populations have seen grey squirrel numbers fall as they provide easy prey for the predators – unlike native reds, a new study shows

Damian CarringtonEnvironment editor

Wed 7 Mar 2018 06.01 GMT

The invasion of grey squirrels that has decimated native reds across the UK is reversed when pine martens prowl the woods, new research has shown. Unlike reds, grey squirrels appear to be easy meat for the predator.

Pine marten populations have also been drastically reduced in the past. But where they are recovering, they send grey squirrel numbers plummeting while reds thrive, according to scientists.

The spread of pine martens from their Scottish stronghold into England is the best long-term solution to controlling grey squirrels, said Emma Sheehy at the University of Aberdeen, who led the work: “It should be all that you need. But it may be some time getting to that place.” As a result, she said it would be foolish to stop current control programmes now.

There were once 3.5 million red squirrels across the UK, but the introduction of “ornamental” grey squirrels from the US in the 1870s has left just 250,000 reds, mostly in Scotland. The larger greys carry a pox disease which is deadly to reds, and also outcompete their smaller cousins.

Pine martens have also suffered, having been killed for their fur and as predators of poultry and game birds, and are essentially extinct in England. They only gained legal protection in the 1980s but there are now a few thousand in Scotland.

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