Sea otters are back, and their return is a breath of fresh air for the waters of Monterey Bay. Marine ecologists Brent Hughes and Kat Beheshti reveal how re-planting seagrass, along with help from a healthy population of crab-eating otters, have transformed and stabilized an entire marine ecosystem.

In the heart of Monterey Bay, California, sits a nature-lover's paradise called Elkhorn Slough. This 7-mile estuary is one of the state's last great coastal wetlands and home to over 100 sea otters, but it wasn't always this way. In the 1800s and 1900s, sea otters were on the brink of extinction from excessive hunting for their fur, and Elkhorn Slough was falling apart from coastal development. Crab populations exploded out of control, and the Slough’s banks began to wash away. 

Thanks to a lucky discovery and some help from a dedicated reintroduction effort, sea otter numbers rebounded. Their crab consumption is finally restabilizing the Slough, from the banks all the way down to the seagrass.