Underwater World Wonders

The greatest diversity of life on Earth is actually in the sea. Over 70 percent of the Earth is covered by ocean, taking up 85 percent of the surface area from the equator to the South Pole. Sea beds are riddled with massive geologic formations that rival the Grand Canyon; mountain chains that run for thousands of miles; and coral reefs formed by organisms over thousands of years. Over 350 different species of coral live on the Great Barrier Reef alone and it is so big it can be seen from outer space. Although the largest creatures in the world can be found in the ocean, most creatures living in the sea are smaller than your thumb. The first global census of marine life logged 230,000 species in 2010 but for every species known, scientists estimate that at least four have yet to be discovered.

However, the health of our oceans hangs in the balance. Overfishing, degraded habitats, pollution, invasive species, climate change and low oxygen areas unable to support life are all causes for concern. Plastic debris causes the deaths of more than a million seabirds and 100,000 marine mammals every year; 50 percent of mangrove ecosystems have been destroyed globally; commercial marine fisheries discard 27 million tonnes of sea life annually; and a recent increase in harmful algal blooms suggests that we have affected the bottom, as well as the top, of marine food chains.

The Environmental Photographer of the Year’s Underwater World category wishes to share the incredible secrets that the oceans, lakes and even ponds hold, as well as highlight the vital role they play in our world's survival. Photographers have until 31st July to submit their entries via www.epoty@ciwem.org.