Total panoramic vision in the mallard duck, Anas platyrhynchos.
The mallard duck has a retinal visual field giving 360 degrees visual coverage in the horizontal plane and a narrow binocular field of approximately uniform width (approximately equal to 20 degrees) extending through 220 degrees from the bill to directly behind the head. Measurement of the optical fields indicate that the binocular retinal field could be considerably larger than actually found. Eye movements are not of sufficient amplitude to abolish binocularity at any elevation.
D000818:Animals; D003867:Depth Perception / Q000502:physiology; D004372:Ducks / Q000502:physiology*; D005133:Eye Movements; D014794:Visual Fields