Zooplankton feeding on algae and bacteria under ice in Lake Druzhby, East Antarctica

• Published in: Polar Biology
• Main Authors: Sawstrom, C, Karlsson, J, Laybourn-Parry, J, Graneli, W
• Format: Article in Journal/Newspaper
• Language: English
• Published: Springer 2009
• Subjects: Biological Sciences; Microbiology; Microbial Ecology; Antarctic; East Antarctica; Lake Druzhby; Antarc*; Antarctica; Polar Biology
• Online Access: http://www.springerlink.com; https://doi.org/10.1007/s00300-009-0619-0; http://ecite.utas.edu.au/57520

The feeding of the cladoceran Daphniopsisstuderi on algae and bacteria was investigated under ice in anultra-oligotrophic Antarctic lake from late autumn (May)to early spring (October) in 2004. D. studeri fed on both algaeand bacteria with estimated filtering rates of 0.048 and0.061 l ind-1 day-1), respectively. Algae seemed to be themajor food resource for the D. studeri population, however attimes of low algal densities the bacterioplankton representedan important alternative food resource. The D. studerigrazing impact on the algal and bacterial standing stock wasin general low (0.64.6% removed per day), but during thewinter period this organism can remove up to 34% of thebacterial production (BP). At times D. studeri grazing cantemporarily have a significant impact on the BP rates, thoughtheir impact was relatively low when compared to viralinducedbacterial mortality in the lake.