Call to end beaver culls as numbers surge in Tayside
The estimated population in the region has risen from about 150 in 2012 to about 430.
The number of beavers has more than doubled to more than 400 in one Scottish region, a survey has found.
Beavers were spotted in Tayside in 2006 due to authorised releases, four centuries after they were hunted to extinction across Scotland.
The estimated population in the region has risen from about 150 in 2012 to about 430, according to a new Scottish Natural Heritage (SNH) survey, and the animals are spreading into the Forth River catchment area.
The environment agency is setting up a mitigation scheme to help farmers deal with problems caused, such as feeding on crops and damage to fences.
However, a wildlife charity has called for a ban on unregulated beaver culls as the report found numbers in some areas are falling.
It found active beaver territories in Tayside have risen from an estimated 40 in 2012 to more than 100.
Researchers recorded 72 beaver lodges, 339 burrows, and 86 dams or recently removed dams across the region.
The report states: "In some areas, namely parts of the lower River Earn and River Isla which are associated with prime agricultural land-use, negative changes in densities of signs were recorded.
"This may represent areas in which culling has been known to have occurred."
The report adds culls are unregulated meaning current estimates of between 50 and 240 animals killed are "completely unvalidated".
Nick Halfhide, SNH's director of sustainable growth, said: "By building dams, beavers improve local water quality and help nurture other wildlife, and it's wonderful that people now have a chance to see these fascinating creatures in their natural habitat.
"But in some parts of Scotland, beavers can cause problems, particularly in areas with prime agricultural land.
"So we are setting up a mitigation scheme - with input from a range of interest groups such as NFU Scotland through the Scottish Beaver Forum - to develop and trial techniques to help farmers deal with any problems they encounter."
A Scottish Government spokesman said: "We've been quite clear in our intentions to bring forward legislation to give beavers protected species status, and a great deal of work has been carried out - and continues to be carried out - in order to lay the necessary groundwork before the legislation can be introduced."