Instead, scientists have suggested that flying in vee formation is a way of maintaining visual contact and avoiding collisions. Further study is clearly required before the reason for flying in vees becomes clear. SEE: Skimming: Why Birds Fly Low Over Water.ne theory has been that all but the lead bird are able to gain lift from the wing-tip vortices produced by the bird in front of them. Those vortices are formed by air rushing up over the tip from the high-pressure area under the wing into the low-pressure area above the wing.