A circus polar bear rescued 40 years ago and brought to live at Bristol Zoo helped change zoos forever.

Misha - who died in 1992 -became the centre of an international animal rights campaign because of the depressed behaviour he displayed in his enclosure.

His suffering was caused as much by his circus experience as because of the enclosure he was held in at the zoo, bosses said.

Misha's story was picked up around the world and it became a turning point in how animals are kept in zoos globally.

You can see more about this story on Inside Out West on the iPlayer.