Lessons from how pumas and wolves interact in North America can be applied here in New Zealand, as we strive towards a predator-free 2050. Dr Heiko Wittmer has looked at what happened when wolves were reintroduced to Wyoming's Grant National Park . The wolves had a negative effect on the pumas in the park and that led to a much more balanced ecosystem. Heiko joins Emile to talk about innovative approaches to controlling predators.