I wondered what the ducks were going to do. Just before the lip of the spillway, the three ducklings, which had been preceding their mother downstream, backpeddled furiously. Their mother went over the edge and not very gracefully landed in the pool below, flapping and squawking. The ducklings paddled over to the shore, clambered out of the water, and portaged around the spillway, rejoining their mother below.
This is the opposite of how I'd expect a human family to behave. If it were a mother with three kids in boats, the mother would say, "Now children, let's climb out and carry our boats down below the dam," while the children would say, "But mom, we want to go down the water-slide!"