Daphnia p&x (Crustacea, Cladocera) was fed the blue-green algae (Cyanophyceae) Anacystis nidulans, Synechococcus elongata, S. cedrorum, Merismopedia sp., Anabaena flosaquae, Synechocystis sp., and Gloeocapsa alpicola. The green algae ( Chlorophyceae) Ankistrodesmus falcatus and Chlorella uulgaris were used for comparison. Direct observations were made of D. pulex feeding in depression slides fi...

Rapid growth could significantly reduce methylmercury (MeHg) concentrations in aquatic organisms by causing a greater than proportional gain in biomass relative to MeHg (somatic growth dilution). We hypothesized that rapid growth from the consumption of high-quality algae, defined by algal nutrient stoichiometry, reduces MeHg concentrations in zooplankton, a major source of MeHg for lake fish. ...

Daphnia p&x (Crustacea, Cladocera) was fed the blue-green algae (Cyanophyceae) Anacystis nidulans, Synechococcus elongata, S. cedrorum, Merismopedia sp., Anabaena flosaquae, Synechocystis sp., and Gloeocapsa alpicola. The green algae ( Chlorophyceae) Ankistrodesmus falcatus and Chlorella uulgaris were used for comparison. Direct observations were made of D. pulex feeding in depression slides fi...

The functional response of Daphnia, a common pelagic herbivore in lakes, was assessed with a combination of secondary and meta-analyses of published data and new data from an experiment conducted using very low food levels. Secondary analyses of literature data (28 studies, n = 239-393) revealed a significant positive influence of food concentration on Daphnia clearance rate at low food levels,...

Correlations between the biomass of phytoplankton and the biomass of bacteria and between the biomass of bacteria and the biomass of protozoans suggest that there is coupling between these compartments of the "microbial loop." To investigate this coupling on the species level, bacteria and protozoans from untreated lake water inocula were allowed to grow on detritus of the green alga Ankistrode...

The seston of the small, shallow, and tropical lake Monte Alegre was tested for quantity and quality for cladocerans by growth bioassays, which were carried out in spring (Daphnia gessneri and Moina micrura), summer (D. gessneri, M. micrura, Ceriodaphnia cornuta, and Simocephalus mixtus), and winter (D. gessneri and D. ambigua). Cohorts of newborns originating from ovigerous females collected i...

This study aimed to investigate the infection status, worm development, and phylogenetic characteristics of the intestinal trematode, Stellantchasmus falcatus. The metacercariae of S. falcatus were detected only in the half-beak (Dermogenus pusillus) out of the 4 fish species examined. Their prevalence was 90.0%, and the intensity of infection was 919 metacercariae on average. Worms were recove...

Half-beaked fish, Dermogenus pusillus, collected from Mueang, Hang Dong, Doi Saket and Saraphi Districts, Chiang Mai Province, were examined for their infection status with Stellantchasmus falcatus (Digenea: Heterophyidae) metacercariae. The infection rate of the fish was 100%. Fish in three of four districts were found only to have metacercariae of S. falcatus, whereas those in Saraphi Distric...