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

• 26 Discovery Channel (Firm)
• 19 Fothergill, Alastair
• 11 Nihon Hōsō Kyōkai
• 7 BBC Earth (Firm)
• 5 Berlowitz, Vanessa
• 4 Byatt, Andrew
• 3 Brownlow, Mark
• 3 Cordey, Huw
• 3 Linfield, Mark
• 2 Barton, Miles
• 2 Holmes, Martha, 1961-
• 1 Allen, Penny, Dr
• 1 Bass, Karen
• 1 Bassett, Peter (Documentary television producer)
• 1 Jeffs, Kathryn
• 1 Keeling, Jonny
• 1 Rees, Dan
• 1 Wanda Distribución de Films

• 26 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

• 26 Documentary television programs
• 26 Nature television programs

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