| Popis: |
Eight starlings (Sturnus vulgaris) radio-equipped in a winter roost in Oregon returned to the roost each night, but not necessarily to the same area within the roost. Individual starlings tended to have major diurnal activity ranges (MDARs) in the same general area on succeeding days. The dis- tance between the birds' center of activity (geometric center of the MDAR) and the previous day's center averaged 4.8 km, whereas the distance between the center of activity and the roost averaged 18.0 km. The mean activity radius of the MDAR averaged 0.8 km. Home range size averaged 39.6 km2. Starlings moved towards the roost earlier on completely overcast days, and those farthest from the roost were generally the first to move. Flock size was not consistent throughout the day, nor was there a dis- cernible pattern of buildup or breakdown except when flocks increased at staging time. |
