SEEN - SE European Bird Migration Network
Autumn migration of Thrush Nightingale (Luscinia luscinia) in Austria

Thomas Zuna-Kratky

AURING – Biologische Station Hohenau – Ringelsdorf, Hohenau/March, Austria

Thrush Nightingale was once breeding in the floodplains of the rivers Danube, Morava and Dyje in the northeast of Austria. Since 1850 there has been no proven breeding record any more, but the species is still a rare but probably regular migrant in late spring and early autumn. In spring singing males are easily detected and occurrence is well documented. Postbreeding migration is much more secretive und therefore little is known about the autumn migration of Thrush Nightingale in Austria.
It was possible to collect a total of 72 records of this species from the years 1967 to 2005. 92% of these records come from ringing stations, only six records were field observations. On average 1.8 birds/year were recorded, but numbers varied a lot between 0 (12 years) and 12 (2005) birds, indicating strong year-to-year fluctuations. The records are concentrated in eastern Austria along the eastern and southeastern edge of the Alps. Apart from this area there is only one record from the Lake Constance.
96% of the observations are from the short period between 6 August and 23 September, the migration peaks in the 48th five-day period (24–28 August) with 33% of all records. One injured bird was recorded very late from 24 October to 1 November 2004. 79% of the records were between 05:00 and 09:00 CEST.
The ratio of juveniles is high with 86% of all aged birds. With one exception (juvenile on 25 July 2005) all birds had already finished moult.
20% of all ringed birds were retrapped, the average length of stay was 6 days (range 2–10). Body mass increases during migration-time, indicating fat gain during migration in Austria. Single birds in southern locations had finally “filled up” their fat deposits. Migration peaks 4 days earlier in northeastern than in southeastern Austria, with an average distance of 216 km between these regions.
Thrush Nightingale is a rare, but obviously regular autumn migrant to eastern Austria with strong variation in numbers. Recapture rate, mass gain during migration and difference in timing between northern and southern stop-over sites indicate that the birds use habitats in eastern Austria as “fuelling-stations” during autumn migration and move quite slowly through this area. Comparison with the situation northeast and southeast of Austria would be of interest.

Created by Pronetix 2006