A comparison of benthic secondary producer communities and production rates among lake types

Aquatic consumers (fish) are heavily reliant on benthic secondary production (invertebrates).  However, benthic secondary production is rarely estimated for a single taxon, much less for an entire community.  This research gap is likely due to methodological difficulties and a pelagic focus in limnology.  As a case study, I examine whole-community benthic secondary production in four northern Wisconsin lakes.  These lakes vary greatly in size, substrate, landscape position, and benthic community structure.  Results suggest that benthic invertebrate biomass and production per square meter are lower in small lakes in northern Wisconsin than in large lakes.  This result may explain why, in general, benthic invertebrates are an important energy source to fish even in lakes that are dominated by large pelagic volumes.  I also address the methodological difficulties associated with estimating secondary production and provide practical guidelines for those who wish to use this valuable metric.