Avian botulism toxicity is a common cause of death to water and shore birds that live near or migrate through Lake Michigan. The botulism neuro-toxin type E (bontE) gene is responsible for the production of botulinum neurotoxin type E. Quantitative Polymerase Chain Reaction (qPCR) was performed using a Step One Plus Thermocycler (Applied Biosystems) and protocol described in Getchell and others, 2011, Journal of Aquatic Animal Health. The assay was used to assess microbial community DNA obtained from environmental samples that were collected by Great Lakes Science Center and by National Park Service from 2011 to 2014 for the bontE gene. Samples were obtained by ponar grab or by divers and matrices collected included sediment, Cladophora, mussels, mussel micro habitat, and invertebrates. This data set is comprised of qPCR data, reported in gene copies per gram wet weight of material for each environmental matrix assessed. Ancillary information specific to sample collection is also included in the data-set, e.g., date, year, site, substrate type, depth, SER, "other description", MIBaRL ID, core depth in centimeter, matrix, collection agency, and copies per gram wet weight as an average reported value.