The Pantanal, in western Brazil, is the world’s largest tropical wetland, and home to tens of thousands of animal species. But expansion of shipping and development is causing an increase in wildfires, and the loss of unique habitats. The Jaguar is the apex predator in the Pantanal, roaming over vast hunting grounds, but the changing environment means that they are now under threat too. Reporter James Harper travels down the rivers of the Pantanal, talking to activists, conservation experts and local businessmen to explore the debate over the future of the Pantanal and its famous big cats.