Grandparental responsibility

As you know, I have six lovely grandchildren, but this morning I woke up to find that I now have nineteen. It's a complicated story, so I will just pick out the highlights. About a month ago, I noticed that the female Mallard in my garden had taken to squatting in the long grass at the base of the plum tree just outside my back door. Could she be on eggs?
The two males that accompanied her everywhere (I don't know which is the husband and which the fancy man, but they both tripped the light fantastic with her from time to time) were in constant attendance.
Anyway, this morning, I looked out to see that she was in the garden pond with thirteen ducklings. That is prolific. As to the fathers, they disappeared the moment I screamed (with joy, that is), and haven't reappeared since.
Now I feel a heavy responsibility for the safety of the thirteen fluffies. I have put an upturned wheelbarrow near the pond, but I doubt if it will fool the foxes. Meanwhile, the crows and the jackdaws are circling....
With drama like this, who needs Springwatch?