Ornis Hungarica. vol.15-16. (2008) p.25-34.
Habitat choice and dynamics of migrating populations of the Robin (Erithacus rubecula) during the autumn migration season
At the Bird Ringing Station of Tömörd (47Â°22'N, 16Â°41'E), located in Western Hungary, ringing and measuring of Robins has been carried out between 1999 and 2003 in the autumn migration period from the end of July to the mid-November, using the methods of Actio Hungarica. During the five years, 3432 specimens of Robins were ringed and measured. By using the ringing data of birds captured the autumn migration dynamics, body mass, wing-length and fat load of birds were analysed. The population change index of yearly number of birds show decreasing trend from 2000 to 2003. On the basis of stopover time of birds recaptured in the study area and what the migration curves show, four migration periods (waves) could be defined in all years, for example in 2000: I. 19 Aug - 17 Sep, II. 18 Sep - 11 Oct, III. 12 Oct - 5 Nov, 6 - 18 Nov. The migration dynamics of juveniles and adults did not differ significantly. Median dates of the autumn migration generally fall in the first week of October. The average wing-length, body mass and fat load of birds captured during the first migration period were significantly smaller than that of birds captured later. According to the ringing and biometrical data it is supposed that Robin populations from Poland and Slovakia pass through in the second half of September and in October, whereas those from Finland and NW-Russia pass through in November.