Jackdaws flap their wings to save energy

For the first time, researchers have observed that birds that fly actively and flap their wings save energy. Biologists have now shown that jackdaws minimize their energy consumption when they lift off and fly, because the feathers on their wing tips create several small vortices instead of a single large one. The discovery could potentially be applied within the aeronautical industry.

Source: Jackdaws flap their wings to save energy — ScienceDaily