Some feared they might wreak damage across the countryside, but a study of beavers in Scotland reveals that, while they may be getting a little bolder, they still don't go far.

Between May 2009 and September 2010, 16 European beavers were released into Knapdale Forest near Lochgilphead, Argyll, in five distinct family groups, for a five-year scientific trial.

Nine beaver kits have been born since then. Five beavers have been confirmed to have died and eight are missing from the trial area and are presumed dead, leaving 12 today in four families.

Scottish Natural Heritage has been closely monitoring them, and their effects on the environment, in partnership with a number of other independent organisations.

The latest report shows that in the 12 months up to November 2011, there was a minor shift in beaver activity to areas further from the water's edge, but that 72% was still within 10 yards of the loch shores.

The most intensive gnawing and felling was within 500 yards of active beaver lodges.

At the end of the trial, the results of the monitoring work will help the Scottish Government decide on the longer term future of beavers in Scotland.