10 Doctor Who Mysteries You Didn't Know Were Answered
2. Is The Duck Pond Important?
Part way through The Eleventh Hour, the Doctor and Amy are walking through Leadworth's village square, and he points out that the duck pond doesn't have any ducks in it. Amy replies that there's never been any ducks in the pond, but they call it that anyway.
Rather than being one of Steven Moffat's many throwaway gags, the duck pond exchange is framed as something important to be paid off later, which it never was. But that wasn't the original plan.
Moffat has answered the question of what was going on with the duck pond at least twice – once in his Doctor Who Magazine column, and again in a recent interview with Inverse.
His original intent was to reveal that the ducks had been victims of the crack in time, and like Rory and Amy's parents, had been erased from time. The ending of The Big Bang would've seen the TARDIS dematerialise from Leadworth village square, to reveal the ducks back in the pond.
Unfortunately, unpredictable weather meant that they were unable to shoot the scene. As a result, it was relocated to the more controllable environment of Amy's back garden, losing the duck pond resolution altogether. How ri-duck-ulous.