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Long term seasonally intensive plankton data sets are important for understanding food web dynamics and assessing resilience. To complement lake wide cruises, nutrients and lower food web parameters from one nearshore (8m) and one offshore (60m) station in western Lake Ontario were sampled from May to October beginning in 2013. The results showed that the stations were both oligotrophic. Total Phosphorus was similar at both stations at around 15 µg/l and Chlorophyll a was 2-3 µg/l. Total phytoplankton biomass was 455 µg/l at the offshore site and slightly higher at 538 µg/l at the nearshore site. Diatomeae contributed the most (35%) to total phytoplankton biomass at the offshore site followed by phytoflagellates (Chrysophyceae + Cryptophyceae + Dinophyceae). Composition at the shallow site was more variable. Mean primary productivity was similar at both sites (5-6 mg C/m3/hr) and was dominated by nanoplankton (>40%) and picoplankton (30%). The above data plus species composition changes will be presented to discuss the continued the oligotrophication of the western Lake Ontario. The necessity and utility of long term trophic data sets to supplement the routine lake wide seasonal surveys will be emphasized. [ABSTRACT FROM AUTHOR]