Publication details
Drift of larval and juvenile fishes: a comparison between small and large lowlands rivers
Authors | |
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Year of publication | 2001 |
Type | Article in Periodical |
Magazine / Source | Archiv für Hydrobiologie (Large Rivers) |
MU Faculty or unit | |
Citation | |
Field | Zoology |
Keywords | early stages; juvenile fish; drift behaviour; downstream movement |
Description | Drift of early developmental stages of fishes was studied in two adjacent lowland rivers (Danube River basin, Czech Republic) which differed in size. Both rivers have been channelised, however only the Morava has been regulated by weirs. Drift was sampled at ten day intervals between May and August 1997. A 15 minutes sampling period was conducted every 3 hours during 24 hours using a drift net with an opening of 0.6 m2. As our sampling season coincided with extensive flooding of the Morava basin in July, we also assessed any effect of this on fish drift. A total of 19 drifting species were recorded. The most abundant species were roach, bitterling and bleak in the Morava and Japanese minnow, bitterling and silver crucian carp in the Kyjovka. Seasonal dynamics of drift were similar between both rivers with two peaks in total drift abundance. A nocturnal pattern of diel periodocity was observed at time of average discharge and disappeared when water transparency decreased during flood. |