Yosemite National Park, CA — Can you build a wall that´s marmot-proof?

Workers at Yosemite National Park sure hope so. The fat, furry mammals known as yellow-bellied marmots have undermined granite boulders that hold up a retaining wall built almost 50 years ago at Olmsted Point.

The point is a popular spot that offers a sweeping view of a glacially carved canyon, without the grueling hike. But Yosemite Association President Bob Hansen says marmots love to burrow into the soil around the rocks, and they´ve compromised the wall.