What role do sea otters play in maintaining the biodiversity of kelp forests?

Sea otters play a crucial role in maintaining the biodiversity of kelp forests primarily by controlling herbivore populations, particularly sea urchins. By preying on these herbivorous animals, otters prevent overgrazing of kelp. If sea urchin populations go unchecked, they can decimate kelp forests, leading to significant declines in kelp health and the ecosystems that depend on them.

This predator-prey relationship creates a balance within the ecosystem, allowing kelp forests to flourish. Healthy kelp forests provide important habitat and food for a variety of marine species, thereby enhancing biodiversity. The absence of sea otters can lead to an explosion in sea urchin populations and result in ‘urchin barrens,’ environments that lack the rich biodiversity found in healthy kelp forest ecosystems.