Shutdown threatens to delay USNPS summer seasonal employee hiring, with possible cascading problems
They answer your questions in the visitor center. They remove trees that winter downed across trails. They even lead you on tours through the Cliff Palace at Mesa Verde National Park.
"They" are seasonal rangers and park staff, thousands of people who enable national parks to function during the high season. And this summer they could be showing up later than normal, which could affect campground openings as well as who is, or isn't, available to answer your questions.