Mixotrophy in Heterocapsa rotundata: A mechanism for dominating the winter phytoplankton

Heterocapsa rotundata is a mixotrophic dinoflagellate that can ingest picoplankton, including bacteria, and is known to form large blooms in temperate estuaries during wet winters, particularly when grazing pressure on phytoplankton is low. We hypothesized that phagotrophy gives H. rotundata an advantage over other phytoplankton species during low light conditions. We used laboratory and field experiments to investigate changes in phagotrophy by...