In situ filtering rates of Cladocera: Effect of body length, temperature, and food concentration

Abstract

The individual filtering rates of the cladocerans in Creteil Lake were measured in the daytime with 14C-labeled ChZorella during a seasonal survey. This mesotrophic, shallow, polymictic lake is characterized by small algae (~25 wrn) and cladocerans (< 1.3 mm). Multiple regression models were established for each genus and for all the cladocerans. Body length alone explained from 44 to 57% of the total variance in the filtering rates of Daphnia spp., Ceriodaphnia spp., and Diaphanosoma brachyurum. An additional 23-34% of the variance was attributable to temperature. The inclusion of the Chl a concentration finally yielded r2 values ranging between 0.79 and 0.84. On the other hand, body length and temperature explained only 16% of the total variance in filtering rate of Bosmina longirostris. By taking into account the effect of factors other than length of the animal, the fit of the model established for all cladocerans improved considerably (from r2 = 0.47 to r2 = 0.83). Species-specific responses and thermal effects in the lake show the difficulty of applying models based solely on body length to obtain sufficiently accurate estimates of cladoceran filtering rates.

Are zooplankton invasions in constructed waters facilitated by simple communities?

“…In general, larger zooplankton are more efficient feeders than smaller ones (Hall et al, 1976;Mourelatos & Lacroix, 1990). Therefore, rotifers could be outcompeted by the larger crustaceans.…”

Disentangling the effect of body size and phylogenetic distances on zooplankton top-down control of algae

“…In freshwater ecosystems, herbivorous zooplankton grazing plays an important functional role by controlling algal blooms and transferring energy and matter upwards through the food chain [18]. Body size of zooplankton has been repeatedly suggested to play a key role in topdown control of algae [19,20], and this trait was found to be evolutionarily labile in cladoceran zooplankton (see electronic supplementary material for details). The importance of body size for top-down control is generally attributed to grazing efficiency asymmetry (selection effect), where larger species are superior grazers (figure 1a) [19,21] and therefore increasing community average size (CAS) might enhance grazing rates (GRs; figure 1c) [22].…”

“…Body size of zooplankton has been repeatedly suggested to play a key role in topdown control of algae [19,20], and this trait was found to be evolutionarily labile in cladoceran zooplankton (see electronic supplementary material for details). The importance of body size for top-down control is generally attributed to grazing efficiency asymmetry (selection effect), where larger species are superior grazers (figure 1a) [19,21] and therefore increasing community average size (CAS) might enhance grazing rates (GRs; figure 1c) [22]. Alternatively, it has been suggested that feeding niche partitioning (complementarity) between large and small zooplankton species may (co)determine top-down control on phytoplankton (figure 1b).…”

Influence de la température sur le développement et la fécondité de quatre espèces de Cladocères planctoniques (Crustacés) en présence de ressources naturelles

“…brachyurum, auxquelles il a été fourni une alimentation naturelle similaire en qualité et en quantité (dominance des Cyclotellà). Connaissant la tempé-rature et la taille des femelles, leur taux de filtration peut être estimé à partir des formules de Mourelatos et Lacroix (1990) et Mourelatos et al (1992). Dans l'intervalle de température 20 à 25°C, ce taux varie de 18 à 30 mL par individu et par jour pour des Ceriodaphnia de 1 mm et de 20 à 40 ou de 40 à 80 mL (selon l'équation utilis.ee) pour des Daphnies de 2 mm, alors qu'il ne varie que de 4 à 8,8 mL pour des Diaphanosoma.…”