Biological Oceanography

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Ingestion and growth rates rise gradually with increasing prey abundance, whereas
clearance rates drop. There are no signs of a threshold of food availability below
which clearance rates are low (Strom et al. 2000). Protists apparently expend
maximum effort seeking food when none is available. As for copepods, small-scale
shear (turbulence) can enhance encounter rates between protists and potential prey, as
shown for the helioflagellate Ciliophora by Shimeta et al. (1995). Food-web
processes among the very small denizens of the sea can also double back on
themselves, with heterotrophs extracting chloroplasts from their prey and maintaining

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