Unexpected Ducks arrival

Someone put two female ducks over the fence into the paddock which has the pond. I would imagine they were pets because they are not nervous and one holds onto my trousers at feeding time. I would have happily taken them if the person had asked as I would not turn any bird away, except Cockerels.

The other important reason I would like people to ask me, rather than just dump them in with my existing birds, is that I always isolate newcomers for a while to make sure they are not suffering from any disease or mites that could be transmitted to the birds here already

If anyone has birds that they can no longer look after, please talk to me before abandoning them.