Use of Bio-fluorescent Characteristics for Ecosystem Monitoring on Hydrothermal Deposits

A new technology is necessary for effective monitoring of deep-sea hydrothermal ecosystems towards the environmental impact assessment of marine mining projects. For this purpose, we develop a new deep-sea observation technique using bio-fluorescent characteristics. Ultraviolet (UV)-LED illumination and violet laser illumination are used for fluorescent video recording of a variety of deep-sea organisms. This study reports the bio-fluorescent patterns and colours observed for a variety of deep-sea organisms and their usefulness for monitoring.