Environmental factors influencing the vertical migration of planktonic rotifers in a hypereutrophic tarn

Vertical distribution and diel migration of rotifers in a Parana River floodplain lake

“…On the other hand, low oxygen contents are frequent in tropical and subtropical environments (Esteves, 1988), so we can presume a strong adaptation of the species to this environmental characteristic. Reversed migration has often been reported in rotifers, they remain in the surface during the day (George & Fernando, 1969;Dumont, 1972;Stewart & George, 1987) and have higher feeding rates during daytime than at night (Ardnt & Heerkloss, 1989). In the littoral area of El Tigre, the most common behaviour was reversed migration.…”

A review of potential methods for zooplankton control in wastewater treatment High Rate Algal Ponds and algal production raceways

“…D. magna has demonstrated negative phototaxis to ultraviolet light (260-380 nm) and positive phototaxis to white light (420-600 nm) [129]. Rotifers usually have positive phototaxis (coming up to the surface during the day) with migration triggered by photoperiod, algal biomass, DO, and avoidance of predatory or competing zooplankton [130,131]. For example, B. calyciflorus has a positive phototactic response between 350 nm and 420 nm (ultraviolet) and between 500 nm and 650 nm (wavelengths least absorbed by algae) [132], whereas F. longiseta has a maximum positive phototactic response to 460 nm (blue light) [133].…”

Community structure and coexistence of the rotifers of an artificial crater lake

“…It is higher than in the (shallower) lakes studied by George & Fernando (1970) and by Stewart & George (1987). It is highest in summer, when migration amplitudes are larger.…”

“…Comparing winter and summer, we recorded significant variation in migration patterns. Stewart & George (1987) studied migration of rotifers in different months and found a similar variation.…”