Here's how: Ducks are deceptively calm on the water. We see a serene bird gliding effortlessly across the water's surface.
What's real is that their feet are pedaling with great speed and force (if they're in a hurry, that is), and only rarely do you get to see and to realize just how much they are working below the surface for that "effortless" propulsion!
I chose this photo because behind the duck, you can see a bit of his pedal power, water churning, like a mini inboard motor on a boat, a bit of whitewater and a flashing orange leg. Seemingly serene, but peddling like hell below the surface!