Bioluminescence in Gippsland Lakes, Australia

The Gippsland Lakes are a network of lakes, marshes and lagoons in east Gippsland, Victoria, Australia covering an area of about 600 square kilometer. In the summer of 2008, an unusually high concentration of Noctiluca scintillans, a bioluminescent microorganisman, turned the waters a bright, glowing blue. Photographer Phil Hart happened to be there to document the amazing display.

Noctiluca scintillans, also known as “sea sparkle,” “sea fire,” “sea ghost”, are a species of dinoflagellate that feed on algae, plankton and bacteria. In December 2008, unusually heavy rain followed by floods caused a high concentration of blue-green algae called Synechococcus in the waters that prompted a higher-than-usual population of N. scintillans in the Gippsland Lakes. It is believed the combination of bush fires and floods created the high levels of nutrients in the lakes for the organisms to feed.

N. scintillans uses its bioluminescence as a defense mechanism, lighting up when it senses a predator coming near. The ghostly glow attracts even larger predators to eat the first predator, keeping the N. scintillans.

Using a long exposure on his camera, Hart had his friends splash in the water to light up and spread the bioluminescent organisms around. In other photos, Hart put his camera on a very slow shutter speed and threw sand and pebbles into the water to activate the glow.

During the remainder of 2009, the Gippsland Lakes returned to “better health" and the water turned cleaner and clearer, as the life cycle of the algae exhausted the nutrient supply from the sequence of fires and floods that started in late 2006. Phil Hart days that bio-luminescence might be visible in the lakes again but it may be a lifetime before it matches this vivid outburst of December 2008 and January 2009.

[via Webecoist]