I love this little observation by James Mather…
“I was on a ladder clearing the gutters end of last week, and over a period of hours heard a number of flocks of birds gathering to migrate, and I could see them heading off in V-formation. Then, at one point, low cloud closed in, but I could hear birds, but not see them. Then, I happened to look up to see through a small gap in the cloud, a formation directly overhead.
So, the formation of the group and its initial direction were set without any visual reference. They were navigating by other means.”
We agree that animals navigate my other means and we think that it is likely that they have a sense of direction as they set out. The “V” shape allows a leader to do all the work and the others to use the slip stream to use less energy.
Work at Oxford suggests that the more navigators (lead birds) in a flock the better as they all nudge each other to find the best route and the result is the course is the best course as adapted by them all.