Investigations on egg production and mortality of cod (Gadus morhua L.) and plaice (Pleuronectes platessa L.) in the southern and eastern North Sea in 1987 and 1988
Heessen, H.J.L.; Rijnsdorp, A.D. (1989). Investigations on egg production and mortality of cod (Gadus morhua L.) and plaice (Pleuronectes platessa L.) in the southern and eastern North Sea in 1987 and 1988. Rapp. et Proc.-Verb. Cons. Int. Explor. Mer 191: 15-20
In: Rapports et Procès-Verbaux des Réunions du Conseil Permanent International pour l'Exploration de la Mer. Conseil Permanent International pour l'Exploration de la Mer: Copenhague. ISSN 0074-4336, more
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Keywords |
Biological production Cells > Sexual cells > Eggs > Fish eggs Dispersion Population characteristics > Biomass Population functions > Mortality Properties > Biological properties > Fecundity Spatial variations Gadus morhua Linnaeus, 1758 [WoRMS]; Pleuronectes platessa Linnaeus, 1758 [WoRMS] Marine/Coastal |
Authors | | Top |
- Heessen, H.J.L., more
- Rijnsdorp, A.D., more
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Abstract |
This paper presents the results of egg surveys for cod (Gadus morhua) and plaice (Pleuronectes platessa) in the eastern English Channel and the southern and eastern North Sea up to 57 degree 00'N in the winter of 1987 and 1988. The spatial distribution of stage 1 + 2 eggs is given for cod and of stage 1 eggs for plaice. Total production of fertilized eggs is given for both years. The present values of egg production were compared with values reported in the literature and showed a close correspondence with the trend in female spawning stock biomass as estimated from Virtual Population analysis. In 1987 and 1988 egg mortality until hatching was 95.0% and 96.7%, respectively, in cod, and 82.8% and 92.6% in plaice. |
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