highly dynamic ecosystems, aesthetic marvels

As part of American Wetlands MonthMI Environment presents a history of the state of the Great Lakes report.

The Great Lakes are loved by many and in many ways define the quality of life for Michigan residents. Michigan is the only state nestled in the center of a freshwater ecosystem that accounts for 20% of the planet’s surface freshwater.

Boaters, swimmers, hunters, anglers, artists, bird watchers, and people from all walks of life come to the shores of these lakes to add value to their lives in many ways. The coastal marshes, dune and swale complexes, lake plain meadows and fens that dot the shores of these wondrous lakes are havens for fish and wildlife, as well as the many people who love to enjoy the serenity of these unique systems.

What is a coastal wetland?

Wetlands are areas where water covers the ground or is present at or near the surface of the ground all year round or for varying periods during the year. Commonly known as bogs, swamps or marshes, wetlands are home to certain types of vegetation or aquatic life. Coastal wetlands, found along the shores of the Great Lakes region, are biological sanctuaries, unique and highly dynamic ecosystems, and aesthetic wonders. They are essential to the health of the Great Lakes.

Benefits of coastal wetlands

Wetlands are considered valuable because they purify water, recharge water supplies, reduce the risk of flooding, and provide habitat for fish and wildlife. In addition, wetlands provide recreational opportunities, aesthetic benefits, and benefits for commercial fishing. Extremely biologically productive, they serve as spawning and nesting habitat for many of Michigan’s fish, wildlife, migratory birds, and waterfowl. Marsh and wetland vegetation anchors sandy shorelines during periods of high water, protecting the shoreline from the erosive effects of Great Lakes waves and ice.

How coastal wetlands are changing

Coastal wetlands are constantly changing, reacting each year to changes in water levels, weather conditions and impacts on the surrounding landscape. Great Lakes water levels fluctuate as part of a natural cycle over time, and coastal wetlands respond to water level changes in several ways. During periods of high water, many coastal wetlands become sparsely vegetated or submerged water beds. During periods of low water, many coastal wetlands change to densely vegetated wet grasslands and emergent communities, often expanding to cover large sections of exposed lake bottoms.

Threats to coastal wetlands

Threats to coastal wetlands include climate change, invasive species, shoreline hardening, development, inputs of nutrients and pollutants from runoff and others. Despite their highly adaptable characteristics, the quality of coastal wetlands continues to deteriorate due to these factors.

Loss of Great Lakes Coastal Wetlands

Michigan has over 275,000 acres of Great Lakes coastal wetlands, but has lost about 50% of the coastal wetlands that existed before European settlement. In some parts of the state, losses can reach 90%.

Great Lakes Coastal Wetlands Monitoring Program

The Great Lakes Coastal Wetlands Monitoring Program (GLCP) began in 2011 and continues a successful basin-wide Great Lakes coastal wetland monitoring program using a scientifically validated sampling plan for plants, invertebrates, fish, amphibians, birds and water quality. The CWMP is a long-standing partnership of 15 Great Lakes Basin organizations, led by Central Michigan University and funded by the United States Environmental Protection Agency. Field teams from research organizations sample approximately 1,000 coastal wetlands every five years, providing a large and continuous data set for coastal wetlands over a rolling period. The results of this project are also being used to inform the planning and evaluation of wetland restoration projects throughout the Great Lakes region.

Legend: Coastal wetland in Delta County on Lake Michigan where black tern nest monitoring takes place. Pictured is Joe Kaplan of Common Coast Research. (Photo courtesy of MNR.)