An unprecedented algal bloom of sea sparkle (Noctiluca scintillans) has created a special picture off the Belgian coast. A Coast Guard team was alerted about possible oil pollution, but the colours didn't match 100%. It turned out the long strip of orange-coloured sea water was due to a natural phenomenon. The blooming is exceptional - it may have been caused by the heat and a lack of strong sea winds. Sea sparkle is harmless, though when it dies, this can cause a lack of oxygen in the water, which may impact on fish.