Particle-Grazing and Plankton Community Impact of an Omnivorous Cichlid

Ray W. Drenner, Scott B. Taylor, Xavier Lazzaro, Dean Kettle

Transactions of the American Fisheries Society · 1984 · 55 citations · 4 references

Abstract

We determined selective ingestion of different sizes of suspended polystyrene particles by filter-feeding blue tilapia Tilapia aurea. Blue tilapias from 4.3 to 18.7 cm standard length selectively fed on particles larger than 25 μm. We compared the plankton communities of pond quadrants with and without fish. Blue tilapias suppressed populations of the large-sized algae Uroglenopsis sp. and Ceratium sp. and the zooplankter Keratella sp. Populations of the small-sized algae Rhodomonas sp., Chrysochromulina sp., Chlamydomonas sp. and Cyclotella sp. and the zooplankter Diaptomus sp. were enhanced by the presence of blue tilapia. As an omnivorous filter feeder, blue tilapias act as size-selective phytoplankton grazers and escape-selective zooplankton predators. Received August 26, 1983 Accepted March 24, 1984

References

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