Visitors are streaming in and out of Yosemite National Park this summer. It’s one of the most popular tourist destinations - for both Californians and out-of-state visitors. But behind the scenes, many seasonal employees at the park are struggling. An NPR investigation found that dozens worked for weeks - without pay - before they were officially hired. The California Report’s Keith Mizuguchi speaks with Chiara Eisner, an NPR Investigative Reporter who worked on this story.