Reaction of wild Hooded Crows to conspecific mummified in particolar postures and exposedin the field.A method for preparing bird specimens to be used as stimulus-objects in the field was tested bymeasuring the response of wild Hooded Crows,Corvus corone cornix.In a first series of experiments,HoodedCrows specimens were tested for general responsiveness and posture discrimination by conspecific.Moreapproaches were consistently made to Bristle-head posture than to Sleeked posture.In a combination of bristle-head specimens of different subspecies and species,C.c.corone was approached more times than C.c.cornix,whereas C.frugilegus elicited intermediate interest.In a different combination of bristle-head specimens,C.c.corone was more attractive than C.c.cornix,whereas a hybrid C.c.corone x cornix was less attractive than eachpure form.The approaches were usually aggressive.Bristle-head posture was confirmed to be a self advertisingposture and the comparisons between subspecies provided suggestions about the mechanism againsthybridation. Reaction of wild Hooded Crows to conspecific mummified in particolar postures and exposed in the field. A method for preparing bird specimens to be used as stimulus-objects in the field was tested by measuring the response of wild Hooded Crows, Corvus corone cornix. A first series of experiments, HoodedCrows specimens were tested for general responsiveness and posture discrimination by conspecific. More approaches were consistently made to Bristle-head posture than to Sleeked posture. In a combination of bristle-head specimens of different subspecies and species, Cccorone was approached more times than Cccornix, whereas C. ferrugilegus elicited intermediate interest. In a different combination of bristle-head specimens, Cccorone was more attractive than Cccornix, while a hybrid Cccorone x cornix was less attractive than eachpure form. .Bristle-head posture was confirmed to be a self advertisingposture and the comparisons between subspecies provided su ggestions about the mechanism againsthybridation.