The Huron-Erie Corridor (HEC) is the connecting channel between Lake Huron and Lake Erie, including the St. Clair River, Lake St. Clair, Detroit River, and western Lake Erie. The HEC contains the largest freshwater delta in the Great Lakes, supports over 65 species of fish, 16 of which are classified as threatened or endangered, and is one of the busiest navigation centers in the United States. Historically, the HEC supported a highly productive fishery, providing spawning and nursery habitat for 80 fishery species, including lake trout, lake sturgeon, lake whitefish, lake herring, walleye, and yellow perch. Unfortunately, over the last century, fish productivity in the HEC has been dramatically reduced due to construction of shipping channels, which severely altered fish spawning grounds and nursery habitats. The goal of this GLRI project is to enhance native fish populations through restoration of fish spawning and nursery habitats in the HEC and St. Clair and Detroit Rivers Areas of Concern (AOCs). The USGS is providing vital information to define restoration targets in AOCs, and is measuring restoration success through pre- and post-habitat construction assessments. This work is being completed as part of the greater Huron-Erie Corridor Initiative (http://huron-erie.org/), a highly collaborative initiative started in 2004 by the USGS Great Lakes Science Center and over 20 partners to restore habitats and native fish and wildlife species in the corridor, ultimately providing societal, economic, and environmental benefits to the Great Lakes region.