Pine martens to the rescue
PINE martens can help support red-squirrel conservation efforts, according to a study published last week in a Royal Society journal. Researchers examined the relationship between the predators and red and grey squirrels in Northern Ireland; they found that pine martens suppressed the greys and ‘had a positive influence on red-squirrel occurrence at a landscape scale, especially in native broadleaf woodlands’.
This confirms findings in 2018 about the animals’ beneficial impact on red populations in the right habitats. However, the study also discovered that, in non-native conifer plantations, the presence of pine martens reduced red-squirrel numbers, leading scientists to argue that restoring natural predators must go hand in hand with creating and maintaining ‘natural, structurally complex habitats’.
‘We have known for a long time that red squirrels do best and have the highest population densities in broadleaf woodlands where there is a good supply of large seeds, fungi and nuts.
They are capable of living in mixed broadleaf and coniferous woodland, but here the populations are less dense,’ explains Stephen Trotter, chair of the UK Squirrel Accord’s Red Squirrel Conservation working group.
Grey squirrels seem to do less well than reds in mixed and conifer woodlands, so, over the past 25 years, forestry advice has been to plant conifers to discourage the greys. However, this has failed to stop their spread. ‘As a result, the soundness of the conifer-only policy has been questioned in recent years, especially as the populations of native predators, such as pine martens, recover,’ notes Mr Trotter. ‘This new research provides direct evidence on this.’