Archive footage of a group of beavers being parachuted into wilderness in the US has been found by historian Sharon Clark.

The film, made around 1950, was lost for years; it had been labelled incorrectly and stored in the wrong file.

The air drops were conducted by the Idaho Department of Fish and Game because they had an overpopulation of beavers in some areas.

It is thought all of the animals made it through their flights unharmed.