Head orientation in pigeons during landing flight.

Landing flights of pigeons were video recorded or filmed, and frame-by-frame measurements were made of the angle of the head relative to the horizontal, and of the position of the perch in the visual field. The angle of the head increases above that seen in free flight, to a value which is correlated with the trajectory of approach to the perch. As a result, the perch is fixated 20-25 degrees above the beak early in landing flight. The possible significance of the behaviour is discussed in relation to specialised retinal areas and to lower-field myopia.