ABSTRACT: Grass shrimp are abundant, ecologically important inhabitants of estuarine ecosystems that have been used extensively in laboratory experiments. However, optimal laboratory feeding conditions have not been determined. We used a laboratory experiment to determine the effects of food availability on survival, growth and reproduction in adult Palaemonetes pugio Holthuis and hatching success of their offspring. Fifteen groups of 50 shrimp were fed 1 of 5 rations of TetraMin® flake food, a standard laboratory diet, for 12 wk; supplementary amounts of newly hatched Artemia sp. nauplii were also given twice weekly. Adult survival, female reproductive condition, and embryo hatching success were determined every 2 wk. Growth was determined from measurements at the beginning and end of the study. Limited food availability caused severe mortality and reduced growth of female shrimp, whereas male shrimp were not affected. Reproduction, as measured by percent gravid females and individual clutch size, was not affected by food availability. However, estimated population-level embryo production was reduced indirectly for the lower rations through mortality and smaller size of females. Hatching success was low in all treatments. Further studies are needed to determine optimal laboratory feeding conditions for grass shrimp so they may be better utilized as predictors of responses in the field.
KEY WORDS: Feeding · Reproduction · Grass shrimp · Palaemonetes · Food limitation · Nutrition · Hatching success
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