Close-up of beluga whale swimming in water. Graham Swain / EyeEm / Getty Images
Beluga whales are normally found in icy Arctic and subarctic waters. So onlookers were undoubtedly surprised to spot one of the distinctive white whales swimming very far south in the UK's River Thames.
Ecologist and ornithologist Dave Andrews first posted footage of the unusual sighting onto Twitter on Tuesday and said the whale was feeding around the barges near the town of Gravesend in northwest Kent.