A healthy coral reef - vibrant lush corals everywhere I look. This is one of the most lush and rich coral reefs we have found in New Caledonia and I am totally thrilled by the glittering cloud of bright blue damsel fish rising up from the crystal coral branches. Freddy surfaces next to me and says, laughing, they look like seaquens. When we approach they form shoals and shy away but we can see them undisturbed, further off in the clear water, a glitter of sequens scattered throughout the water snatching tiny zooplankton from the sea. They shift colors from luminous turquoise green to iridescent blue, sometimes the whole school does it in one harmonious whoosh of color.

It is the most vivacious coral forest we've found and the largest schools of Chromis viridis we've found. The two creatures, the coral and the fish, are made for each other and this particular display of mutual aid is a particularly beautiful example of symbiosis - the fine art of "living together".

When danger threatens the fish dive down and hide in the branches of the coral. When the coral is as abundant as this forest of Acropora the entire school of fish can vanish completely in the protective branches. The fish also sleep in the protective arms of the corals, safe from the many species of nocturnal predators that prowl the night reefs. The lower regions of the coral branches are no longer living and Chromis attaches its eggs to these well hidden surfaces during the summer. The male then guards the eggs until they hatch. When we examine the vast shoals of fish we can see a whole range of sizes from tiny little fish only a few months old to some about 90 mm long. Most of them are less than 50mm long.

The coral benefits from the association, too.

The clear waters of the tropical south Pacific are very poor in nutrients - phosphates and nitrates - coral needs in order to survive. The thin layer of tissue creating the calcium carbonate coral branches is an association - a symbiosis - of plant and animal cells; about one third animal cells and two thirds plant cells. The animal cells protect the plant cells and provide them with nutrients and carbon dioxide - and the plants provide the animal cells with oxygen and sugars for energy. To support the plant growth the animal cells form tentacles which snare nutrients from the sea currents. They capture some plankton but they also catch the constant precipitation of nutrient pellets ejected by the clouds of tropical fish that swim above them. The fish effectively extend the biological reach of the corals up into the water and in a way we can think of the Chromis sequens as extended tentacles of the symbiosis that is the coral reef.

Scientists have found that when the population of fish above a coral reef declines the corals develop diseases, growth slows, and the association dies. And these days, dead and dying reefs are the norm - and wondrous coral and fish associations like this one are very limited in extent.

It makes me particularly happy to be able to show you this example of harmony on the coral reefs of New Caledonia and I thank the team at www.360cities.net for the opportunity to extend the symbiosis of the coral reef into the electronic consciousness of humanity.