• 4 Bears
• 3 Brown bear
• 1 Alaska Earthquake, Alaska, 1964
• 1 Black bear
• 1 Climatic changes
• 1 Description and travel
• 1 Dinosaurs
• 1 Friendship
• 1 Greenhouse effect, Atmospheric
• 1 Grizzly bear
• 1 Lakes
• 1 Paleontology
• 1 Permafrost
• 1 Polar bear
• 1 Rivers
• 1 Sinkholes
• 1 Stream ecology
• 1 Vertebrates, Fossil

• 4 Morgan, Chris, 1968-
• 4 National Geographic Channel (Television station : Washington, D.C.)
• 4 Thirteen Productions
• 4 WNET (Television station : New York, N.Y.)
• 3 Pontecorvo Productions
• 3 Pontecorvo, Joseph
• 3 Wildlife Media (Firm)
• 2 Blink Films
• 1 BBC Studios
• 1 Boffey, Mercer
• 1 Chan, Oscar
• 1 Curry, Ann, 1956-
• 1 Gilbert, Louisa
• 1 Habeger, Brice
• 1 Hayes, Michael J. (Voice actor)
• 1 Hess, Janet
• 1 Moore & Moore Productions
• 1 Moore, Shane
• 1 Prasad, Ashok
• 1 Robinson, Jeannette (Narrator)
• 1 Tanner, Nick
• 1 WGBH (Television station : Boston, Mass.)

• 8 English

• 1 Admiralty Island (Alaska)
• 1 Arctic regions
• 1 Tongass National Forest (Alaska)
• 1 Yukon
• 1 Yukon River (Yukon and Alaska)

Limit year range