• 24 Videos, Slides, Films

• 21 Ecosystem management
• 18 Ecology
• 11 Marine ecology
• 10 Marine organisms
• 9 Biotic communities
• 9 Pollution
• 7 Air
• 7 Climatic changes
• 6 Ocean life
• 5 Animal behavior
• 5 Reproduction
• 5 Water
• 4 Archaeology
• 4 Biodiversity
• 4 Biogeography
• 4 Biology
• 4 Conservation of natural resources
• 4 Environmental aspects
• 4 Natural resources
• 4 Oceanography
• 4 Population
• 3 Biosphere
• 3 Refuse and refuse disposal

• 6 Infobase
• 6 National Geographic Television & Film
• 4 Ampersand Film & Video Tape Productions
• 3 Allegro Productions (Firm)
• 1 BBC Worldwide Ltd
• 1 Cambridge Educational (Firm)
• 1 Electric Sky (Firm)
• 1 Journeyman Pictures (Firm)
• 1 MacNeil/Lehrer Productions
• 1 NPO/Netherlands Public Broadcast
• 1 System TV (Firm)

• 24 English

• 2 Hawaii
• 2 South America
• 1 Alaska
• 1 Australia
• 1 Burma
• 1 Earth (Planet)
• 1 Mexico
• 1 Mexico, Gulf of
• 1 Oceania
• 1 Outer space
• 1 Serengeti National Park (Tanzania)
• 1 Tanzania
• 1 United States
• 1 Yellowstone National Park

• 24 Educational films
• 24 Internet videos
• 24 Videorecording
• 2 Video recordings for the hearing impaired

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