Numbers of the British vole - which inspired Ratty's character in the children's classic The Windin the Willows - have plunged from seven million to less than a million in a decade.
His other production credits include TV film The Windin the Willows, which was voiced by the likes of Vanessa Redgrave, Michael Gambon, Michael Palin and Alan Bennett.
She says the defining characterisation of the animals in the 20th Century was framed by Kenneth Graham's classic The Windin the Willows with its gruff, wise, brave Badger.