We got ducks a few days after our pond started to fill up - we were very excited as we love watching them waddle around - however, we have been advised not to encourage them until our pond is fully established, as they have a taste for fresh new shoots - and given the price of pond plants, they could be a very expensive addition to a pond. We also had two very annoying Canada geese that would land on our lawn at the crack of dawn and stand outside our bedroom window honking. I spent a couple of weeks running after them in my dressing gown until I managed to comically slip over one frosty morning and realised I needed a better solution. They have a perfect sense of how long it takes to get close to them - I'd start running at them, while they would slowly waddle down to the pond and glide into the middle where I couldn't get close to them - and then taunt me by honking at me again. The solution to make them go away is quite simple - get some brightly coloured rope and make it criss-cross your pond, 6" above the water-line. This "spooks" them - they like to be able to land on and take off from water, so they soon leave your pond alone. It doesn't look good of course - we're treating it as a necessity though until the pond has established. For mallard and other ducks, rope a few inches off the ground around the pond will spook them. Ours did work out how to land in a "vertical take off" fashion on the pond - and it was quite amusing watching them duck their heads to go under the ropes - they soon decided it wasn't an ideal situation though, and seem to be frequenting our neighbours large pond instead!
We were very excited to see a Mallard Duck pair that visited the pond yesterday and I managed a quick video of them. 
