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Biology

Keystone Predators and Ecosystem Biodiversity

Quick fact

When sea otters were hunted to near extinction along the Pacific coast, kelp forests disappeared. The explosion of sea urchin populations—the otters' main prey—grazed the kelp down to barren rocks, reducing biodiversity dramatically.

Why this is interesting

In the coastal waters of the Pacific Northwest, a single predator helps create a thriving underwater forest. How can one animal be so powerful that its mere presence controls the entire ecosystem's biodiversity?