Feeding and filtration rates of zooplankton (rotifers and
cladocerans) fed cyanobacteria (Microcystis aeruginosa) alone or
in combination with the green alga (Scenedesmus acutus)
Alfredo Pérez Morales*, S.S.S. Sarma & S. Nandini
Laboratorio de Zoología Acuática, Edificio UMF, Universidad Nacional Autónoma de
México, Campus Iztacala, Av. de lo Barrios, no. 1, Los Reyes, Tlalnepantla, Edo. de Méx.
C.P. 54090. México. E-mail: alfredo_pm@yahoo.com.mx
Ecotoxicological works are biased towards pesticides or other man-made toxic
substances. In nature zooplankton groups including rotifers, cladocerans and copepods
also suffer from natural toxic substances produced by the cyanobacteria, especially
Microcystis aeruginosa. In this work, we quantified the feeding and filtration rates of
zooplankton (three rotifer species: Brachionus calyciflorus, Brachionus rubens and
Plationus patulus and three cladoceran species Daphnia pulex, Moina macrocopa and
Ceriodaphnia dubia) on sonicated (predominantly single cells) M. aeruginosa alone and
with different proportions of Scenedesmus acutus (25, 50 and 75%, based on cell density).
The zooplankton species were offered 100,000 cells/ml of M. aeruginosa (or with S.
acutus) and the grazing period was for 20 min. The results showed differential feeding and
filtration rates on M. aeruginosa by the zooplankton depending on the presence of
Scenedesmus.
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Oral presentation; *presenting author