The PEG-model of seasonal succession of planktonic events in fresh waters

The 2002 alewife year class would have exerted high predation pressure on zooplankton by fall of 2002 because biomass and consumption rate of age-0 fish typically peak in summer and fall of their first year of life.

“This year class would have exerted high predation pressure on zooplankton by fall of 2002 because the biomass and consumption rate of age-0 fish typically peak in summer and fall of their first year of life (Sommer et al. 1986).”

The timing and extent of the spring clear water phase correlates with peak Daphnia abundance.

“In particular, the timing and extent of the spring clear water phase cor-relates with peak Daphnia abundance (Lampert et al. 1986, Sommer et al. 1986, Rudstam et al. 1993, Meijer et al. 1999).”

The spring clear water phase ends as predation on Daphnia by planktivorous fish and invertebrates increases through spring and early summer, causing Daphnia populations to decline and phytoplankton biomass to increase.

“This clear water phase ends as predation on Daphnia by planktivorous fish and invertebrates increase through spring and early summer, causing Daphnia populations to decline and phytoplankton biomass to increase (Sommer et al. 1986).”

The trophic cascade is more relevant to the spring and early summer when phytoplankton are more often strongly regulated by zooplankton grazing than in the summer.

“The trophic cascade is more relevant to the spring and early summer when phytoplankton are more often strongly regulated by zooplankton grazing than in the summer (Sommer et al. 1986, Rudstam et al. 1993).”