We bought and raised from a couple days old two Rouen ducklings and luckily I have a male and female... They share a home with our chickens and goats and everyone gets along great! When thy were still very small we kept them In the house and let them play in the sink and eventually in the tub and then they were moved outside where we have a big pond for them... Since they've been outside they swam A bit in the very beginning for a couple days but never went back into the water and would only play in little puddles... How can I encourage them to swim in the pond?