How wildlife contribute to the health of an ecosystem

PACIFIC OCEAN

When the fur trade wiped out North America’s sea otters in the early 20th century, sea urchins—a favorite otter food—exploded in number. The voracious creatures came to blanket the sea floor, gobbling up kelp forests wholesale.

These 60-foot-tall masses of seaweed beneath the Pacific serve as nests and nurseries for fish, especially the kinds that coastal economies are built on. They protect coastal towns from storms. They store carbon dioxide and help keep the water clean. Like many other ecosystems, kelp forests are crucial for humans and animals alike.

But conservation efforts shouldn’t overlook the role of the animals that shape them, argues Rebecca Chaplin-Kramer, WWF scientist and lead author of a new paper on this subject. “Understanding the hidden contributions wildlife make to creating and maintaining the places that protect us, nourish us, support us in so many ways is essential,” she says.

When sea otters were reintroduced in the 1960s, for example, kelp forests grew back. With the ecosystem again in balance, a coastal revival took place—and local businesses built a sea otter tourism industry worth millions. Kelp forests may do the heavy lifting, but otters are the reason they exist today.