The wake of a jackdaw (Corvus monedula) in slow flight

摘要: The wake of a jackdaw in slow forward flight is described. three-dimensional velocity field was investigated qualitatively and quantitatively by analysis multiple-flash stereophotographs the motion neutrally buoyant helium bubbles. best description structure appears to be chain planar, nearcircular, discrete, small-cored, vortex loops, each produced vorticity shed during single downstroke. However, momentum measured such approximately 35% that required for weight support under these conditions. Some evidence presented this apparent deficit may arise because real distribution too simplistic. implications results theoretical models bird are briefly discussed.