Douglas Heaven, reporter
Up a bit... left a bit... a bit more... ah, that's the spot. (Image: Mikael Buck/Rex Features)
Named after his adoptive father, London mayor Boris Johnson, Boris the green turtle doesn't get a tickle from the cleaner every day. The divers above are taking part in Sea Life London Aquarium's annual January "Deep Clean", in which tanks and inhabitants get a good scrub.
Despite being capable of breath-holding dives of over 10 hours - the longest of any vertebrate - green turtles are usually found in shallow lagoons in the warmer parts of the Atlantic and Pacific Oceans. But every three to four years they swim thousands of kilometres from their regular foraging grounds to remote beaches where they mate and the females lay eggs in holes in the sand. Hatchling turtles then face a desperate race to the relative safety of the sea while birds, crabs and other predators pick off the stragglers.
Those that make it to adulthood have been shown to have an amazing homing ability - possibly guided by smell. Not only do they return to their own birthplace to breed, but they can retrace exact routes across an ocean to favoured feeding sites.
Though some have questioned green turtles' endangered status, sea turtles generally don't have it easy. As well as animal predators, baby turtles must also now contend with changing weather and human interference.
London Aquarium staff hope that Boris junior's new family connection will help raise awareness of their plight. "I hope he's got a thick skin," said Boris (the mayor).