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Beobachtungen über die Eientwicklung des Blaufelchens (Coregonus lavaretus wartmanni) im Bodensee-Obersee
Authors:Prof Dr Erich Braum  Heinz Quos
Institution:1. Institut für Hydrobiologie und Fischereiwissenschaft der Universit?t Hamburg, Olbersweg 24, D-2000, Hamburg 50, BRD
2. Fischermeister, Institut für Seenforschung und Fischereiwesen, Untere Seestrasse 81, D-7994, Langenargen, BRD
Abstract:Lake Constance whitefish (Coregonus lavaretus wartmanni) spawn in the water column. The demersal eggs develop at the mud-water interface at depths down to 250 m. Samples were taken by dredging areas of 100 m2. Mortality, developmental stages and rate of malformations were determined. Incubation period lasts roughly from December to March. The percentage of dead eggs increased from 52% in January to 74% in February. Among living eggs deformations of the trunk raised from 4% to 31% during the same time. It is assumed that larvae with anomalities of the trunk will have no survival chances. Total losses were 91.7% in the average of all samples.
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