Grand Marais Breakwater & Piping Plover Conservation

When the City of Grand Marais, Michigan, petitioned for a replacement breakwater to increase the safety of its harbor on Lake Superior—the only significant harbor between Munising and Sault Ste. Marie—the U.S. Fish & Wildlife Service worked to ensure the protection of piping plover habitat.

Grand Marais was historically a significant contributor of young piping plover to the endangered Great Lakes subpopulation.

RES was engaged to compare plover nesting and reproductive success to habitat configurations over time, from the 1930s to the present. In addition, RES studied lake level changes, shoreline development, shoreland pedestrian use and wildlife interactions. RES evaluated impacts on habitat due to these factors, and predicted changes in the shoreline at 5- and 30-year intervals, to evaluate different alternatives.

RES studies indicated that a sharply angled breakwater would minimally affect piping plover habitat and populations, and that it would instead create new nesting habitat, despite some impacts to young plovers due to gull predation and other factors.

Overall, the breakwater balances the need for a safe harbor with the need to maintain a healthy plover population at Grand Marais.