You may have used Google Maps to see your street or a street far away. Now you can use Google technology to see beneath the surface of the planet’s oceans. While sitting at your computer, you can explore six coral reefs and wave to the fish and giant turtles as they swim languidly by. The project is sponsored by Catlin Seaview Survey, an Australian organization that seeks to “record and reveal the world’s oceans and reefs like never before.” Google is a founding partner of the survey.
Although the views are beautiful, you may be dismayed by what else you find on your watery journey. The tiny animals that build coral are dying at an alarming rate, leaving behind dead, grey reefs. By 2050, some 60 percent of the world’s coral reefs may be dead.
Coral faces many hazards, both natural and human-made. Among the natural dangers are violent cyclones, diseases, and the changes in water temperature, sea level, and salinity caused by El Niño seasons. The coral animals are also subject to being eaten by a variety of predators. The most voracious is the crown-of-thorns sea star, a multi-armed starfish the size of a dinner plate, that can quickly lay waste to a coral reef. These starfish have increased in number, probably because the fish that feed on it have declined.
Reefs also face human threats. Discarded plastic bags can suffocate coral. Coastal development can muddy or pollute previously clean reef habitat. Some fishing techniques, whether for food or to supply the aquarium trade, wreck reefs. Oil spills interrupt coral reproduction cycles. Global climate change has changed ocean water temperatures, adversely affecting coral.
But do coral reefs matter? Definitely! They have been called the rainforests of the sea, for their biodiversity and the number of species—from fish to seabirds to turtles—that depend on them. Coral reefs protect shorelines by absorbing wave energy. They draw tourist in droves. In fact, one estimate puts the annual global value of coral reefs at $375 billion!
Image credit: © Mika Specta/Fotolia
- Catlin Seaview Survey
Take the underwater tours at the Catlin site.
(Source: Underwater Earth; accessed October 31, 2012)
- Ocean Portal: Corals and Coral Reefs
The site has everything you wanted to know about coral reefs. It includes diagrams, maps, photos, and more. Note to teachers: It also includes lesson plans.
(Source: Smithsonian National Museum of Natural History; accessed October 31, 2012)
- Great Barrier Reef Has Lost Half of Its Coral in the Last 27 Years
The Great Barrier Reef, east of Australia, is the largest coral reef in the world. Learn about the dangers it faces.
(Source: Australian Institute of Marine Science, October 2, 2012)
- Hazards to Coral Reefs
The NOAA describes natural and human-caused threats to coral reefs.
(Source: National Oceanographic and Atmospheric Administration, August 17, 2012)