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Effect of differential gastric evacuation and multispecies prey items on estimates of daily energy intake in juvenile Chinook salmon

A.S. Kolak·D.W. Rondorf
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Abstract

The caloric density of stomach contents in juvenile chinook salmon, Oncorhynchus tshawytscha , was not affected by gastric evacuation, suggesting a constant caloric density of stomach contents during evacuation. Differences in the caloric density of prey consumed did affect caloric density of stomach contents over a 24-h period. Consumption of the amphipod Corophium sp. was associated with reduced caloric densities of stomach contents. During periods when Corophium contributed more than 4% of the stomach contents, average caloric density declined from 5.56 to 5.33 kcal g −1 . Despite this difference, estimates of daily energy intake of juvenile chinook salmon were only 3%, greater when developed from the mean caloric density of stomach contents excluding Corophium .

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A.S. Kolak, D.W. Rondorf. 1987. Effect of differential gastric evacuation and multispecies prey items on estimates of daily energy intake in juvenile Chinook salmon. https://doi.org/10.1007/bf00001883

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