Owing to the enormity and complexity of the Laurentian Great Lakes, an ecosystem classification is needed to better understand, protect, and manage this largest freshwater ecosystem in the world. Using a combination of statistical analyses, published knowledge, and expert opinion, we identified key driving variables and their ecologically relevant thresholds and delineated and mapped aquatic systems for the entire Great Lakes. We identified and mapped 77 aquatic ecological units (AEUs) that depict unique combinations of depth, thermal regime, hydraulic, and landscape classifiers. Those 77 AEU types were distributed across 1997 polygons (patches) ranging from 1 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.
|Original language||English (US)|
|Number of pages||20|
|Journal||Canadian Journal of Fisheries and Aquatic Sciences|
|State||Published - Jan 1 2018|
Bibliographical noteFunding Information:
The Great Lakes Aquatic Habitat Framework (GLAHF) project has been funded by the Great Lakes Fishery Trust (22016.1678); continuing support and development has been funded by the State Wildlife Grant T-10-T-7 through the Michigan Department of Natural Resources Fisheries Division, the University of Michigan Water Center (N015421), the Great Lakes Basin Fish Habitat Partnership (3003.8, USFWS-Coastal), and the International Joint Commission (P1500170). Partial support for development of habitat data layers was provided by grants from the Environmental Protection Agency Great Lakes Restoration Initiative and NOAA Center for Sponsored Coastal Ocean Research: NA09NOS4780192, NA10NOS4780218. Numerous people have contributed to the classification and mapping effort, including D. Forsyth, P. Urista, J. Kelly, P. Seelbach, D. Brenner, J. Anderson, J. McKenna, and P. Zuzek. We are grateful to the staff and scientists of the Great Lakes Science Center for the use of their extensive fish collection data from Lake Ontario. We are indebted to all of the people who contributed to make the GLAHF classification project a success. We thank the reviewers for their efforts to improve this paper. This is publication No. 621 of the Natural Resources Research Institute, University of Minnesota Duluth, and contribution 1859 of NOAA Great Lakes Environmental Research Laboratory. The views expressed in this paper are those of the authors and do not necessarily reflect the views or policies of the US Environmental Protection Agency.