Twitchers at the London Wetland Centre, Barnes, were surprised to discover a young mallard duckling with its mother last week.
But the mild autumn has produced an even bigger shock as the mother has now hatched about 15 ducklings, which were caught on film earlier this week.
The tiny creatures face a tough challenge to stave off the cold winter weather if they hope to survive.
Site Manager John Arbon said: "Of course it’s highly unusual to have ducklings this late in the year but we’re hopeful that if the warm weather lasts a bit longer it will give them time to build up their strength.
"They are in our World Wetlands area where we feed the birds so they are benefiting from a bit of extra food each day which will give them a helping hand."
How we reported the arrival of the first duckling in Friday's Richmond and Twickenham Times
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