UK law - killing/catching predators?

I posted here a couple of weeks ago about a cat attacking one of my
Ducks.
Anyway, the same cat has been sniffing around again, and it is a big
cat, so quite capable of killing a duck - luckily they saw it this time,
and made a fast run for the house.
I know I can kill a fox, rats or other vermin on my land.
Farmers are allowed to shoot dogs that attack their animals, so would it
be legal to either kill, or trap this cat?


Any thoughts?
Thanks
Alan.


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