Watching ducks and swans take off from the mostly unfrozen lakes the other day, I was impressed with how important those big, webbed feet are in keeping the birds’ bodies up near the surface of the water. For example, a light-bodied, male Hooded Merganser “ran” on the water less than 50 feet before it was air-borne.
The merganser’s feet barely touched the water surface as its rapid wingbeats lifted it into the air.
These small diving ducks weigh only 1-2 lb, so getting air-borne from the water surface is less of an impressive achievement. However, Trumpeter Swans, the heaviest bird in North America, weigh 20-30 lb, and lifting those big bodies into the air requires the combined effort of both feet and wings.
Initially, it looks like a lot of splashing without much lift taking place.
Their bodies are so close to the water on take-off, they can’t utilize their powerful wing down-stroke for lift, so the large surface area of the feet really is essential in pushing the bird up.
Even as the bird begins to lift above the water surface, it still can’t use the down-stroke for lift; the feet continue to propel the bird upward.
And those are some really big feet aiding the launching effort. Swans rarely show off those big appendages that are so useful in water take-offs, as well as digging up the bottom sediment while they forage.
Coming in for landing with webbed feet fully extended to brace for impact…
The birds with probably the longest required take-off pathway from water are the loons. With relatively short wings and legs placed far to the rear, loons need two to three times the distance for take-off that ducks do, and as they take-off, they too appear to be skipping along the water surface — or even hydroplaning.
The true masters of “running on water”, however, have to be the Western Grebes, whose courtship dance is a synchronized ballet of movement across the water, all performed without a single wingbeat, paddling with just their feet in completely upright posture. A clip from David Attenborough’s Life of Birds shows this incredible feat the best.