Grand Canyon NP: This episode is dedicated to ravens. Learn about their distinctive physical characteristics, where they can be found, what they eat, and much more.

Glacier National Park: USGS research biologist Kate Kendall discusses a project to estimate population and distribution of grizzly bears in Glacier National Park and surrounding areas. The method of collecting hair samples from bears is mentioned.

Denali NP & PRES: Discovery of a set of intertwined moose antlers and skulls in a designated federal wilderness area inspires discussion and deeper appreciation of wilderness values.

Canyonlands National Park: Once faced with extinction, the desert bighorn sheep has made a remarkable comeback in southeast Utah thanks to native herds protected in Canyonlands. Join ranger Karen Henker for an in-depth look at this intriguing mammal.

Canyonlands National Park: Throughout Canyonlands, naturally occurring sandstone basins called potholes form tiny ecosystems inhabited by a surprising collection of animals. Join ranger Karen Henker for an introduction to these animals and some their remarkable adaptations.

Rocky Mountain National Park: This video discusses bighorn sheep with emphasis on their movement around the park. Struggles they face due to human ingenuity are discussed as well as how park officials help the sheep overcome man-made obstacles.

Natural Laboratory: Where have all the black abalone gone? How are scientists surveying the remaining population? Why are black abalones eating so much? Tune in for answers to these and related questions.

Natural Laboratory: Tune in to find out how deep-water corals are beneficial to an array of different marine organisms and the factors that could harm the corals. Information is provided by experts at the Cordell Bank National Marine Sanctuary.

Natural Laboratory: Due to higher carbon dioxide output, the oceans have become increasingly acidic. How is this acidity affecting marine organisms with shells? Tune in to find out.

Natural Laboratory: This audio file covers attracting great white sharks to boats so that they can be documented and tagged. They types of tags used are discussed as well as the migration patterns of the great white sharks found off the California coast.