yea, swans can't swim.. they sink to the bottom of any waterbody you put it in.. this is because the swans in game "swim" on a textured pane in their zoo encloser.

I've only managed to get this asset working when place on land (it can't even be placed on water). When I use Move It to put it on water, the swans remain on land (and start headbutting the ground which looks really odd).