It looks as if a lorry carrying tomato ketchup has crashed into the sea. But this weird scene from Clovelly beach in Sydney, Australia, is actually the effects of algae. Some of the city’s most famous beaches have been closed because the algae, noctiluca scintillans, have affected several areas, including the famed Bondi beach. Though the algae is not toxic, they can cause skin irritation and have a strong fishy smell. It is believed to have entered the sea after riverbeds were disturbed by rcent heavy rains. Not all beaches in the area have been closed, and anglers have still been fishing in the affected areas. Red-coloured baits, we are told, have not been working well.