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55:40
Chimpanzees and other primates survive on Tiwai, an Upper Guinea island
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56:43
Madagascar tries to protect its ecosystem while preserving traditions that harm it.
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56:08
Grizzlies, wolves and cougars roam Montana's rugged, pristine Glacier National Park.
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56:13
Filmmaker Hugo van Lawick explores relationships within a wild-dog pack in the Serengeti
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50:23
The human and natural histories of the Grand Tetons and Jackson Hole, Wyoming
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55:51
Whales snatch sea lions from shore as penguins, maras and guanacos go about their business
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52:42
Rangers at Denali National Park train hikers for planned encounters with grizzlies bears.
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56:16
Fire and the Yellowstone National Park ecosystem
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56:08
Fur trade continues to threaten the otter, despite its status as an endangered species
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56:34
River from Rockies to near Sea of Cortez
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54:50
Hugh Miles films Europe's great birds of prey and notes how man's actions endanger them
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55:11
Hong Kong: English Crown Colony history
