I think they are not bored, they are just layback by nature - when there is no action to involve, they are not bothered. Our ducks are very social, and they are very happy and entertained when one - or even better, more - of us is around. They come close, connect to our chat, and always showing that they are curious and open for any fun - which is usually some playtime with them.
"Hide-and-seek" is a good game: I hide somewhere (I am the one who is imprinted by them) and call them loudly - they walk around, look around, and when they found me they got some titbits.
"Iceball" is nice too: I make a ball (or a brick) of ice in a plastic bag, filled with some chopped veggies - when its frozen, I take it out from the plastic bag, and roll it into their pond. It swims on the water surface, and the ducks drift it around happily.
They very much enjoy the "Oyster Table". Despite it's snobbish (well, at least here in the middle of the great plain of Hungary it is snobbish) name, the table is a brick on the side of their pond, where I smash snails with a stone "to order".
When I'm weeding the garden, building something from wood, no matter how loud the powertools are, they keep coming, to see I'm safe, or.. maybe to check if I have something for them, or is it a game for ducks? They think about it. They talk it out with each other.
I scattered a few spadeful of river gravel in their pen, because when I was a little boy I loved to search in it for "treasures", like a rounded quartz, striped, or just for interesting colored little stones. Well, my ducks love treasure-hunting in it too, and they can eat the best size stones for grit.
And they find it just absolutley fascinating when my mother lies in a hammock between two plumtree, reading a book, and they can be very close, and then they organize their feathers, and they know that they have place in our family and they are loved. Also they have patience (all the time in the world) to wait for their playtime, and it is good to rest outside our garden in their own duckshade*, just looking at things while listening to what the birds sing.
(*the shade is an upside down V, made from an old clothes dryer covered with some bulrush"
