Urban birds flee approaching women with longer flight initiation distance than men. Difference averages one meter and holds across Czechia, France, Germany, Poland, Spain. Pattern consistent in 37 species from 2700 observations. Effect persists after controlling height, clothing, speed, flock size, vegetation. Bayesian models account for phylogeny and spatial effects confirming sex effect. All species show trend from tolerant pigeons to cautious magpies. Universal across cities rules out local culture or environment. Birds distinguish human sex via gait, smell, posture or evolutionary cues. Longer FID signals greater caution toward women impacting foraging and breeding. Phenomenon rigid despite urban habituation to humans.