Costs of Flying in a Flock
Sometimes a bird is better off going it alone. We know that big birds like waterfowl such as ducks and geese benefit from the flying-V. Waterbirds like pelicans and cormorants make the most of the chevron formation as well. But according to a study published in Nature, flying in a messy flock does birds like pigeons no favors. In fact, such flocks demand a higher energy cost and, based on my personal experience with Columba livia, a great tolerance for trash birds.