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High degree of uniformity over lake.  Biomass levels lower than lower lakes, intermediate between Superior and Michigan.  Not huge difference between spring and summer.
Main points: Productivity between Superior and Michigan.  Doesn’t have the time lag in community development of Superior, but overall productivity lower than Michigan Species composition more similar to Superior than to Michigan
In oligotrophic lakes, majority of production can occur below epilimnion.  This is because particulates in water column (i.e. algae) sparse enough to permit light penetration to depth, nutrients higher at depth.  Can have potential consequences for depth distribution of zooplankton.
High degree of heterogeneity in profiles.  Unusual for upper lake.  Seems to be north/south differentiation.
Community in spring dominated by calanoid copepods In summer, community biomass larger, dominated by Cladocerans (one species - D galeata mendotae), and both calanoid and cyclopoid copepods Community extremely similar to Lake Michigan (in spite of differences in phytoplankton) No large gradients in community composition - perhaps slight increase in biomass in the south?
Zooplankton communities with mean lengths above 0.8 mm indicative of high piscivore/planktivore ratio (Mills et al).  All upper lakes above this line, lower lakes mostly below this line.  This theory has not been tested much.
No evidence that biomass higher at depth, but nutrient status improved, which could make for better grazing for zooplankton
Dominated by diatoms in spring - surprising percentage of pennates.  Still large percentage of diatoms in summer, which makes it more similar to Superior.  Also, high percentage of chrysophytes.  These are ‘zooplankton friendly’ groups, but also indicative of low productivity.  Chrysophytes are classic ‘clean water’ group.
As with lengths, most individuals are small, but most community biomass is concentrated in larger individuals.  In this graph, cumulative biomass doesn’t quite reach total biomass at site (41.2 mg/m3) because to include it would have extended scale of X axis way out to accommodate a few huge individuals. Since there isn’t a strict relationship between length and biomass (it’s species specific), some individuals in dark orange rectangle are less than 1 mm, some are more than 1mm.