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INFOGRAPHIC
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A Delicate Balance

A Delicate Balance

Rapid purple sea urchin population growth along the California coast has disrupted the local ecosystem. The overabundance of these urchins threatens to collapse the kelp population to the detriment of other species in the ecosystem.

Grades

5 - 8

Subjects

Biology, Conservation, Ecology

ecosystem
noun

community and interactions of living and nonliving things in an area.

fossil fuel
noun

coal, oil, or natural gas. Fossil fuels formed from the remains of ancient plants and animals.

kelp forest
noun

underwater habitat filled with tall seaweeds known as kelp.

marine ecosystem
noun

community of living and nonliving things in the ocean.

population
noun

total number of people or organisms in a particular area.

sea otter
noun

marine mammal with thick fur native to the Pacific Ocean.

sea star
noun

marine animal (echinoderm) with many arms radiating from its body. Also called a starfish.

sea urchin
noun

marine animal (echinoderm) with a circular, spiny shell.

Media Credits

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Director
Tyson Brown, National Geographic Society
Author
National Geographic Society
Production Managers
Gina Borgia, National Geographic Society
Jeanna Sullivan, National Geographic Society
Program Specialists
Sarah Appleton, National Geographic Society, National Geographic Society
Margot Willis, National Geographic Society
Producer
Clint Parks
other
Last Updated

May 20, 2022

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