Forecasting annual cyanobacterial bloom biomass to inform management decisions in Lake Erie

Abstract Blooms of the toxic cyanobacteria, Microcystis aeruginosa , have been both a public health and ecological concern in Lake Erie for over a decade. Although models were previously developed to forecast cyanobacterial bloom severity, the recent few years of bloom severity observations indicate the need to update these empirical models. The models that best estimate the bloom biomass use the Maumee River discharge or total bioavailable phosphorus (TBP) loading from March through July. TBP is the sum of the dissolved reactive phosphorus and the proportion of particulate phosphorus that is bioavailable, corrected for loss due to settling in the river. In years when average June water temperatures were too low for Microcystis growth (