20201207 13530200 1.0 TRUE Aquatic ecological units We identified and mapped 77 aquatic ecological units (AEUs) that depict unique 14 combinations of depth, thermal regime, hydraulic, and landscape classifiers. Those 77 AEU types were distributed across 1,997 polygons (patches) ranging from 1 km2 to > 48,000 km2 in area and were most diverse in the nearshore (35 types), followed by the coastal margin (26), and then the offshore (16). Our classification and mapping of ecological units captures gradients that characterize types of aquatic systems in the Great Lakes and provides a geospatial accounting framework for resource inventory, status and trend assessment, research for ecosystem questions, and management and policy-making. Access the journal publication at https://doi.org/10.1139/cjfas-2017-0242 The Great Lakes Aquatic Habitat Framework (GLAHF) project has been funded by the Great Lakes Fishery Trust and led by Dr. Catherine Riseng, PI at the University of Michigan School for Environment and Sustainability, with partners from Michigan Department of Natural Resources-Institute for Fisheries Research, NOAA Great Lakes Environmental Research Laboratory, International Joint Commission, Michigan State University, The Nature Conservancy, Ontario Ministry of Natural Resources, University of Minnesota-Duluth, U.S. Fish & Wildlife Service, U.S. Geological Survey and many collaborating partners in both the USA and Canada. More information about this project can be found at https://www.glahf.org/.