Red squirrel survival threatened by conservation strategies
Strategies to conserve red squirrels through confer plantations could be achieving the opposite of their intention by threatening the species’ survival, according to latest research.
Strategies to conserve red squirrels through confer plantations could be achieving the opposite of their intention by threatening the species’ survival, according to latest research.
The UK’s population of red squirrels has been in decline after their invasive non-native grey cousins were introduced in the 1890s.
Conservation strategies in the UK and Ireland currently focus on planting non-native conifer trees to tackle climate change and the biodiversity crisis, particularly for red squirrels.
But a study led by Queen's University Belfast and St Andrews University, challenges this approach.
Researchers at the two universities with Ulster Wildlife and the help of citizen scientists used camera traps to survey more than 700 sites across Northern Ireland over five years, looking for red squirrels, grey squirrels and pine martens.
The research, published in Proceedings of the Royal Society B and funded by the British Ecological Society, shows increased numbers of pine martens aided the presence of red squirrels across the landscape because they suppressed the grey squirrel, regardless of habitat.
But this is reversed in large non-native conifer plantations, where the pine marten reduced the occurrence of red squirrels.
The study says this could be due to the lack of alternate prey, and the lack of refuges for red squirrels in highly simplified landscapes. However the research says it is likely that grey squirrels do not survive well in these habitats, and following pine marten recovery, red squirrels have to contend with their nemesis as elsewhere.
“Restoration of native predators is a critical conservation tool to combat the on-going biodiversity crisis, but this must be with maintenance and protection of natural, structurally complex habitats,” said Joshua P. Twining, Queen’s University Belfast researcher and lead author of the study. “This has global implications given the on-going recovery of predators in certain locations such as mainland Europe.
“It also shows that the current national red squirrel conservation strategies that favour non-native confer plantations are likely to have the opposite impact to what is intended. Timber plantations are often promoted as being beneficial to red squirrel conservation, but our results show that they will have a detrimental effect on the species in the future.”