Scientists from the University of Strathclyde in Scotland investigated this. Of course you already know the answer: resistance. Or at least: reduce it. Ducks nest in their mothers’ footsteps because there they have to paddle with less force against the water, just like cyclists who nest in their mate’s wheel to save energy “from the wind”. Now scientists have discovered even more: the first duck, which swims right behind its mother, not only encounters less resistance, but is pushed.
That first duck swims at what the researchers describe as the “sweet spot.” The waves caused by the mother duck rise and fall, just like waves in the sea or a tropical swimming pool. The first duck rests only at the bottom of this wave, so that the little bird is actually surfing with a forward wave and pushing forward.
primal instinct
The effect is passed to the second duck in the line, but in a weaker version. By the time the third duck is reached, the waves have settled and the resistance tends to zero. Then the duck is not pushed, but encounters much less resistance than if it were swimming alone.
The researchers now want to use their observations and calculations to design ship trains, which, like ducks, sail behind each other to save power and thus valuable fuel.
Biologists can also do something with the findings. Naturally, ducklings do not know where to swim, they only feel the less difficult paddling places. At the same time, it is possible for ducklings to be pre-programmed to swim in a row behind their mother. This primal instinct may explain why ducklings automatically follow moving objects on the ground.