Out of 52 chub Leuciscus cephalus tagged with internal radio‐transmitters, 46 migrated to spawning grounds in the River Spree, Germany. All chub started their first spawning migration on 21–22 May in both years of study, 1995 and 1996. They arrived at three different spawning grounds within a day and left after 1 to 6 days to return to their original sites. On 17 and 18 June 1995 and 1996 chub started their second spawning migration with the same pattern as the first. About 60% of all migrating chub moved between 1 and 13 km upstream to the nearest spawning ground. Some exceptions were observed: a few chub did not use the nearest spawning ground, some chub used different spawning grounds at first and second spawning or moved downstream to a spawning ground. Spawning grounds were characterized by 0·4 m s−1 current velocity, shallow depth (0·1–0·8 m) and a stony bottom, where most eggs adhered.

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