Giant rubber duck thrills London - in pictures

Quack idea! A giant-size quacker passes under Tower Bridge ... but only just. The madcap paddle-past was part of the launch for a new £250,000 bursary funding quack ideas aimed at making Britons laugh Photograph: Fever PR

Duck and cover! A team of eight people spent more than 800 hours cutting and welding together parts for the giant duck to ensure it was airtight and didn't sink. Could duck tape have helped? Photograph: Fever PR

All hands on duck! The giant rubber duck passes HMS Belfast – shame it couldn't raise a wing in salute Photograph: Jackpotjoy.com/PA

Duck take! The super-size quacker passes under Tower Bridge ... just Photograph: Lewis Whyld/PA

Duckzilla! The giant rubber duck floats past the Tower of London, much to the amazement of tourists Photograph: Lewis Whyld/PA

Fat duck! A giant duck, towering 50ft high and weighing in at a whopping half a tonne, prepares to float down the River Thames from Canary Wharf in east London Photograph: Jackpotjoy.com/PA