One of the biggest problems facing our oceans is the alarming disappearance of seagrasses, which account for roughly around 15 percent of the oceans' carbon storage.  

In fact, seagrasses bury carbon at a rate 35-times faster than tropical rainforests such as the Amazon and form vital habitats for endangered marine species.

In the Elkhorn Slough estuary of Monterey, California, the impact of heavy agricultural activity degraded the water quality and the marine habitat for the slough's vibrant species. After years of decline, however, the tide might be turning for seagrasses.

In recent years, a hunting ban that allowed sea otters to return to the slough also turned around the fortunes of seagrasses.

Researchers discovered that the sea otters, which are keystone predators, eat crabs that in turn ate slugs which help protect seagrass meadows. Therefore, through their top-down consumption, sea otters have been able to encourage seagrass to flourish and counter the decline of our oceans.

Yasmeen Qureshi explores the unique role that the return of the sea otters have had on the oceans of California.

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