Topics » Science & Technology   Sept. 19, 2011

The Return of the Gray Wolf

Changing Ecosystem

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The Gray WolfCentennial ValleyWolf Pup SkullChanging EcosystemCattle Ranch ManagementPersistent ThreatMontana Landscape Bison HerdMontana HomesteadThe Yellowstone RiverTools of the Trade

Changing Ecosystem

Doug Smith of the National Park Service shows NewsHour science correspondent Miles O'Brien an aspen tree in Yellowstone's Crystal Creek, a thriving example of how the ecosystem has changed since the wolves returned to Yellowstone National Park.

Photo Essay

Photo Essay