This episode explores how a new understanding of nature is helping us find surprising ways to

fix it. Along the Elwha River in Washington, we learn how removing dams has led not only to the

recovery of the local forest but also Chinook salmon, which provide food for the endangered

orca population. In China, one scientist’s determination to restore fireflies, which provide natural

pest control, is transforming the lives of rural farming communities — even tiny creatures can

have a significant impact. The return of wolves to America’s first National Park, Yellowstone,

has rejuvenated the entire landscape, repairing and restoring habitat that had been over-grazed

by herbivores. This pioneering project discovered the crucial role of predators in bringing

balance to ecosystems. In Scotland, planting trees is reversing massive deforestation which

took place centuries ago, helping native wildlife thrive and mitigating some of the effects of

climate change. And in South Africa’s Cape Town, innovative efforts to remove massively thirsty

European pines and other invasive species are helping to restore the watershed, which faced a

severe shortage in 2018 after three years of drought.