Guido Rahr was an unusual young boy; from the age of three, he was exploring the fields and streams near his home in Oregon; by 12 he was an authority on rare snake species; and at 15, he began a life long love affair with the majestic salmon, spending all his time on the Deschutes River teaching himself to fly fish. Salmon, one of the most determined, single minded creatures on earth, have for hundreds of thousands of years succeeded in returning from the sea to their birth rivers to spawn - no matter the conditions or obstacles. But as Guido discovered to his alarm when he started studying them in the late 90s, fewer and fewer were returning each year as the rivers of the US were becoming increasingly inhospitable, due to dams, industry, and climate change. The salmon of the Pacific Rim, it seemed, were set for near extinction, just like the salmon that once filled the Atlantic Ocean. An improbable and inspiring story, Stronghold takes the reader on a wild and at times dangerous adventure as we follow Guido from Oregon to Alaska to one of the world's last remaining salmon strongholds, in the Russian Far East - a landscape of ecological richness and diversity that is rapidly being developed for oil, gas, minerals, and timber. As Guido befriends and navigates scientists, conservationists, corrupt officials, Russian oligarchs, unexpected allies, and impenetrable bureaucracies, he reveals the astonishing natural history of the endangered salmon, a species whose demise will reverberate across the planet. And he sets into motion a plan that can secure their survival.