Seasonal Trends in the Epilimnetic Rotifer Community of Lake Ontario in 2018

Session: Poster Session

Sarah Schaefer, Cornell Biological Field Station, [email protected]
Patrick Boynton, Cornell Biological Field Station, [email protected]
Joseph Connolly, Cornell Biological Field Station, [email protected]
James Watkins, Cornell University, [email protected]
Lars Rudstam, Cornell University Bio Field Station, Dept. of Natural Resources, [email protected]

Abstract

Rotifers are among the smallest metazoans and make up a large component of the planktonic micro-zooplankton community in Lake Ontario. Rotifers are thought to occupy an important position in aquatic food webs and may be useful as trophic indicators. For these reasons biological monitoring of rotifer communities has a long history in the Laurentian Great Lakes. Epilimnetic rotifer samples were collected in 2018 as part of the Cooperative Science and Monitoring Initiative (CSMI) Lake Ontario survey. Samples were collected using a 64 micron mesh zooplankton net towed at a depth of twenty meters or two meters from the bottom at shallower sites. A total of twelve genera of rotifers were encountered from a total of 111 lakewide samples collected monthly from April to September 2018.  Dreissenid veligers and copepod nauplii were also quantified. Seasonal changes in community composition were assessed based on abundance (number of individuals/m³) and biomass (mg/m³). Overall, Synchaeta was the most abundant rotifer genus and Keratella was also numerically important. We summarized and report seasonal trends observed in the epilimnetic rotifer community of Lake Ontario.