Archives at the Institute for Fisheries Research (IFR) hold records of thousands of lake surveys from the University of Michigan and Michigan Department of Natural Resources. The records contained in this dataset are jpeg images of the index card records from the IFR surveys. Images include the front of the card and when available, the back of a card. and
Bottom Food Summary Cards report the samples from the bottom of the lake taken to look for possible food sources for fishes. This information includes the station number, area sampled, depth sampled, bottom substrate type, vegetation, and the organisms per sample. Organisms include round worms, flat worms, gastropods, molluscs, amphipods, water mites, and macroinvertebrates.