Department of Fisheries and Aquatic Sciences, University of Florida, 7922 NW 71st Street, Gainesville, FL 32653, USA.
J Fish Biol. 2009 Jan;74(1):105-19. doi: 10.1111/j.1095-8649.2008.02114.x.
Stable sulphur isotopic composition (delta(34)S) of gizzard shad Dorosoma cepedianum was used to investigate the seasonal and ontogenetic variation in the diet of young and adult fish. This study evaluated fish from a hypereutrophic lake that had recently undergone a 40% reduction of large (>300 mm total length, L(T)) D. cepedianum biomass as part of a biomanipulation experiment, which aimed at reducing internal nutrient loading. Dorosoma cepedianum delta(34)S values showed evidence of ontogenetic changes with young fish (<200 mm L(T)) depending more on benthic food sources than adults (>200 mm L(T)). The delta(34)S composition of the adult fish suggested an increasing importance of zooplankton in the diet, although benthic food sources remained part of the diet of all D. cepedianum collected in this study. The results indicated that benthic feeding is used by D. cepedianum of all sizes, suggesting that biomanipulation efforts may need to target all sizes of fish to realize benefits.
利用胃含物中稳定硫同位素组成（δ34S）研究了幼鱼和成年鱼的食性在季节和发育阶段的变化。本研究评估了经历过生物操纵实验的鱼类，该实验将大型（>300 毫米总长度，L（T））达氏鲷生物量减少了 40%，目的是减少内部营养负荷。达氏鲷的δ34S 值表明存在发育阶段的变化，幼鱼（<200 毫米 L（T））比成年鱼（>200 毫米 L（T））更多地依赖底栖食物源。尽管底栖食物源仍然是本研究中所有采集的达氏鲷的饮食的一部分，但成年鱼的δ34S 组成表明，浮游动物在饮食中的重要性越来越大。结果表明，所有大小的达氏鲷都使用底栖觅食，这表明生物操纵工作可能需要针对所有大小的鱼类来实现效益。
