At Cumberland Island the National Park Service currently is crafting a visitor use management plan that critics say poses a great threat to the national seashore's official and potential wilderness.

To get an understanding of what's at risk, we've invited Jessica Howell-Edwards, the executive director of Wild Cumberland, which advocates for the seashore's wilderness area and ecosystems, to join us.

The Florida Reef stretches from Biscayne National Park south past Everglades National Park and down to Dry Tortugas National Park in Florida. It's roughly 350 miles long, and is the only coral reef in the continental United States.

When it comes to reefs around the world, the Florida Reef is the third largest. But, unfortunately, it's under a lot of pressure. It's dealing with pollution, ocean warming, damage inflicted by anchors, and disease. Perhaps the most serious disease infecting the reef is Stony Coral Tissue Loss Disease, which can be fatal to corals.

Our guest today is Beth Firchau, who works for the Association of Zoos and Aquariums. Part of her role is to manage the association's safe coral program, and part of her role is AZA's coordinator for the Florida Reef Tract Rescue Program. And part of her work involves a network of aquariums across the United States that are holding samples of corals from the Florida Reef.

Whitebark pines are a Western icon that the National Park Service has designated as a "vital sign" species because they are critical to ecosystem functions. But they are at risk of extinction due to climate change, beetles, and a fatal fungus from Eurasia.

Our guest today is Dr. Elizabeth Pansing, the director of forest and restoration science for American Forests, a nonprofit organization that strives to create healthy and resilient forests.

This program was made possible in part by the Park Foundation.