In Dabob Bay, Washington, the annual cycles of phytoplankton standing stock and production rate exhibit spectacular increases (phytoplankton blooms) in the spring and the autumn, indicating a lack of control by the grazer populations. Yet virtually all of the phytoplankton production is ultimately consumed by grazers. Dr. Dagg will test a conceptual model hypothesizing the identities of the micro- and macro-zooplankton grazer species and postulating a mechanism for the annual balance between phytoplankton growth and grazing. This research will field test the hypothetical model. The functional dynamics of zooplankton grazers (both micro and macrozooplankton) will be established on four extended cruises and budgets of carbon flow will be constructed. Grazing rates will be experimentally measured in the field.