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(80-08) Reproduction disorders in Monoporeia affinis, an effect of low quality food resources and contaminants? Sundelin, Brita*,1, Eriksson-Wiklund, Ann-Kristin1, Håkansson, Eva1, 1 ITM , Stockholm University, Stockholm, Sweden ABSTRACT- The deposit-feeding amphipod Monoporeia affinis occurs in large densities in the Baltic and in many fresh-water environments. Variables of the embryogenesis are used as biomarkers in the Swedish Marine Monitoring Programme for detecting contaminated sediments. Embryo development is a very toxicant-sensitive period of the life cycle, and a strong correlation between contaminants and malformed embryos has been recorded. Other embryo aberrations i.e. undifferentiated and dead eggs and dead broods arose due to exposure to abiotic environmental variables like oxygen deficiency and elevated temperature. The usefulness of the method which was developed in brackish-water environments was tested in the greatest lakes of Sweden, Lake Vanern and Lake Vattern. Severe effects on reproduction were recorded in the oligotrophic Lake Vattern. Increased levels of undifferentiated and dead eggs and broods were found. At some stations 80 % of eggs were undifferentiated and 50 % of females carried dead broods. Results were confirmed by three field surveys. Fecundity was very low in comparison with the more eutrophic Lake Vanern. A negative correlation between undifferentiated eggs and fecundity was found. Polyunsaturated fatty acids (PUFA), i.e. eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are indicators of high food quality in planktonic food webs and also precursors to hormones for sexual maturation. Lower concentrations of fatty acids were measured in amphipods from Vattern as compared to amphipod populations in Lake Vanern. In adition, increased level of Cd was recorded in both lakes while the level of malformed eggs just increased in Lake Vattern. Thus, we hypothesize that found effects are a combined effect of limited food resources and contaminants Key words: Monoporeia affinis, embryo development, PUFA, FA |
