Nature: This year’s stock of sockeye salmon in the Fraser River in British Columbia is booming mysteriously. As Nature‘s Nicola Jones reports, one possible—and controversial—explanation is that ash from a 2008 eruption of the Kasatochi volcano in Alaska is responsible. The link between volcanos and salmon is not as far-fetched as it might seem at first. The ash is rich in iron, which fertilizes the organisms at the bottom of the salmon’s food chain: phytoplankton.