Why do ducks fly in a V?

Ducks fly in a V formation when in groups, but why?

There are a couple reasons. The first is that it helps conserve their energy during migrations. Excluding the individual leading the group, each bird trailing behind the other benefits from a reduction in wind resistance. The birds are deliberately tailgating each other. It’s the concept of drafting, best known to those gutsy people who drive close behind semis on the freeway to stay out of the wind and boost their fuel efficiency. Race cars in NASCAR do this as well.

The next time you see ducks or geese flying in a V, watch them for a while to see if the lead bird changes. Whoever is up front is working the hardest, will make a switch. The leader will drops back – usually all the way back, where wind drag is lowest, and a rested bird comes to the front. While there is no single, unchanging leader for a V of birds on the move, it is the oldest, experienced individuals who are calling the navigational shots, using the sun and the stars at night to orient themselves and stay on course.

Something else you might notice is how the V changes shape. Sometimes it looks more like a check mark, with one bird flying lead, two or three birds trailing on one side, and the majority of birds strung out on the other. This too is a strategy for dealing with wind. It usually means a crosswind is blowing and the short side of the formation is taking the brunt of the wind, while on the long side, the birds are attempting to shield one another from it.

The second reason for birds to fly in formation is that this orientation allows the birds to communicate more easily. The V formation provides the birds with good visual contact of each other to keep the flock together. This communication keeps the flock together and minimizes the possibility of losing birds along the way as the formation crosses vast distances during migration.

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