• 17 Marine ecology
• 17 Natural history
• 16 Animals
• 14 Ecology
• 14 Ocean
• 11 Physical geography
• 9 Marine animals
• 8 Marine biology
• 8 Oceanography
• 7 Marine biodiversity
• 3 Coral reefs and islands
• 2 Coasts
• 2 Forests and forestry
• 2 Ocean waves
• 2 Weather
• 1 Animal ecology
• 1 Animal migration
• 1 Autumn
• 1 Biotic communities
• 1 Caves
• 1 Climatic changes
• 1 Desert ecology
• 1 Deserts
• 1 Forest ecology
• 1 Fresh water

• 33 Attenborough, David, 1926-
• 26 British Broadcasting Corporation
• 26 Discovery Channel (Firm)
• 19 Fothergill, Alastair
• 14 BBC Earth (Firm)
• 11 Nihon Hōsō Kyōkai
• 9 Brownlow, Mark
• 7 BBC America
• 7 British Broadcasting Corporation. Natural History Unit
• 7 France télévision
• 7 Open University
• 7 Tencent Pictures
• 7 Westdeutscher Rundfunk
• 5 Berlowitz, Vanessa
• 4 Byatt, Andrew
• 3 Barton, Miles
• 3 Cordey, Huw
• 3 Linfield, Mark
• 2 Doherty, Orla
• 2 Holmes, Martha, 1961-
• 2 Jeffs, Kathryn
• 2 Smith, Jonathan (Producer)
• 1 Allen, Penny, Dr
• 1 Bass, Karen

• 33 English

• 11 Earth (Planet)
• 7 Polar regions
• 6 Antarctica
• 6 Arctic regions
• 1 Everest, Mount (China and Nepal)
• 1 Himalaya Mountains
• 1 Serengeti Plain
• 1 Serengeti Plain (Tanzania)
• 1 Tanzania

• 33 Documentary television programs

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