Wild beavers in good health but fears of damage to land
Studies say river damming and borrowing need to be addressed
BEAVERS that appeared in the wild almost a decade ago are free from disease but still pose threats to agriculture, according to new reports.
The species was hunted to extinction in Scotland about 400 years ago, but now more than 150 are prospering in Tayside, having escaped or been illegally released from private collections.
Genetic tests on 25 of the animals have discovered they are Eurasian and therefore were once native, rather than the alien North American species.
One report showed they are all healthy and free from any parasites or diseases of concern to humans, domestic animals and other wildlife. The beavers are producing young and still spreading through the Tayside catchment. However, the most significant impact has been on farming, especially in the intensively cultivated arable ground on the flood plain where the River Isla meets the Tay.
Beaver dams left in place at this location could “cause the extensive network of drainage ditches to fail, causing flooding and interfering with cultivation of productive land”, the report says.
A number of methods to protect trees from being gnawed and felled and to reduce water levels behind dams have been trialled successfully. But the impacts of burrowing in flood banks and regular damming of drainage networks were said to be “more challenging to manage”.
These issues would need to be addressed effectively if beavers are to remain, experts say.
Since the beavers first appeared a decade ago they have been found in rivers and lochs stretching from Kinloch Rannoch, Kenmore and Crieff in the west to Forfar, Perth and Bridge of Earn in the east.
In 2012 rather than order the culling of the population, then esti- mated to be 100, the then environment minister Stewart Stevenson opted to allow the Tayside beavers to remain in the wild for the duration of the trial reintroduction of beavers in Knapdale in Argyll.
However, the Scottish Gamekeepers Association (SGA) called for more research after warning that the decision could lead to major flooding and forestry problems.
The Tayside Beaver Study Group, including farmers, scientists, forestry, angling and environmental bodies, was set up to monitor their impact on land use.
Its findings, along with those from the Knapdale trial and other research, will help Scottish Ministers decide later this year whether or not to permanently reintroduce beavers to Scotland.
Three reports have now been published by Scottish Natural Heritage (SNH) on behalf of the study group.
David Bale, chair of the group and SNH’s Area Manager for Tayside & Grampian, said: “These are very useful findings. They show there is no evident risk of diseases being transmitted from the Tayside beavers to other animals, or indeed to humans.”
But he added: “If they were to be permanently reintroduced, efficient, effective and affordable ways of managing and reducing potentially significant impacts on intensively farmed land and other interests would have to be found.”