Ecosystem Ecology

The Atlantic grey seal is globally rare—there are fewer grey seals in the world than African elephants—and Britain hosts 40 per cent of this world population. Over the course of a year in their lives, Susan Richardson comes to know a colony of seals, watching as it is hit by storms in the autumn pupping season, experiencing sociable winter haul-outs and sympathising as the colony scratch and fidget through their annual moult.

In Elkhorn Slough, an inlet on the California coast, seagrass grows healthy and strong in the shallow water. This healthy seagrass baffled marine biologist Brent Hughes. The scientist expected this estuary to be overrun with algae, causing the seagrass to die. Why was the seagrass thriving? As Brent investigated, signs pointed to an unexpected player helping to keep the seagrass healthy: sea otters! What do these top predators have to do with an aquatic grass at the opposite end of the food chain?