Studies on functional response and prey selection using zooplankton in the anostracan Chirocephalus diaphanus Prevost, 1803
Por:
Sarma S.S.S., Nandini S.
Publicada:
1 ene 2002
Resumen:
Freshwater cladocerans and rotifers were used as prey to study functional response and prey selection by adult females of Chirocephalus diaphanus under laboratory conditions. For functional response studies, we offered three rotifer species (Brachionus calyciflorus, B. patulus and Euchlanis dilatata) and three cladoceran species (Alona rectangula, Ceriodaphnia dubia and Moina macrocopa) at various densities ranging from 0.5 to 16 ind. ml-1. We found increased zooplankton consumption with increasing prey density but beyond 4 ind ml-1 cladocerans and 8 ind. ml-1 rotifers, the number of animals eaten plateaued. In general, C. diaphanus consumed fewer large prey (cladocerans) and many more smaller zooplankton (rotifers). For prey selection experiments, we used B. calyciflrous, B. patulus, C. dubia and M. macrocopa, offered at the ratio of two rotifers: one cladoceran and at three prey densities (total zooplankton numbers: 3, 6 and 12 ind. ml-1). Prey selectivity patterns followed the functional response trends. In general, regardless of prey types, with an increase in the available zooplankton, there was an increase in the number of prey consumed. At any given prey density, C. diaphanus consumed higher numbers of rotifers than cladocerans. Among the prey offered, B. patulus and M. macrocopa were positively selected. Results are discussed in light of possible control of zooplankton by anostracans in temporary ponds.
Filiaciones:
Sarma S.S.S.:
Laboratory of Aquatic Zoology (UMF), Div. of Res./Postgraduate Studies, Natl. Autonomous Univ. of Mexico, Av. de los Barrios s/n, CP 54090, Tlalnepantla, State of M., Mexico
Nandini S.:
CyMA Project-Aquatic Ecology, Div. of Res./Postgraduate Studies, Natl. Autonomous Univ. of Mexico, Tlalnepantla, State of Mexico, Mexico
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