SREL Reprint #0678




Effects of Food Availability and Water Temperature on the Feeding Ecology of Pond Sliders (Chrysemys s. scripta)

Robert R. Parmenter



Enhanced growth rates and body sizes in populations of aquatic turtles (Chrysemys scripta) from thermally impacted habitats are attributed to differences in diet quality and elevated water temperatures.  A dietary analysis, utilizing a stomach flushing technique, showed that turtles from a nuclear reactor cooling reservoir ingest more than twice as much protein as turtles from natural aquatic habitats.  The major component of the high-protein diet is fish carrion, which is more abundant in the cooling reservoir than in the other habitats.  Both field and laboratory feeding electivity indices show turtles select fish meat over most other food items.  Other dietary components include insects, snails, algae, seeds and aquatic vegetation.

Elevated water temperatures influence the feeding ecology of turtles by increasing ingestion rates.  Previous studies on other digestion processes (assimilation efficiencies, enzyme and gastric acid activity, hormone levels and motility rates) are incorporated into a feeding strategy model for optimizing growth.  Elevated water temperatures in the cooling reservoir may also permit an extension of the turtle’s growing season.


SREL Reprint #0678

 Parmenter, R.R. 1980. Effects of food availability and water temperature on the feeding ecology of pond sliders (Chrysemys s. scripta). Copeia 1980:503-514

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