For those of us lucky enough to call Lake Leelanau's shore home, the lake isn't just a backdrop; it’s a living, breathing neighbor. The tangled reeds, weathered wood, and sturdy wildflowers do far more than just look beautiful. These wild edges we love are a fragile ribbon of life that protects our water and our memories alike. If we want to keep the serenity in our summers and the clarity in our coves, we have to understand and protect the secret world happening right at the water’s edge.
What is a lakeshore ecosystem?
An ecosystem is a natural unit consisting of all biotic (living plant, animal, and microorganism) factors in a specified area, functioning together with all the abiotic (nonliving physical features such as water, rocks, gravel, sand, soil) factors of the environment. The lake ecosystem has well-defined boundaries---the shoreline, the sides of the lake basin, the surface of the water, and the bottom sediment. Within these boundaries, the lake ecosystem is divided into several zones which are determined by the amount of light able to penetrate through the water. The shoreline zone in which the water is shallow enough for light to reach the bottom is more specifically known as the littoral zone. A healthy littoral zone provides important functions, or "ecosystem services," for the lake. For example, in a healthy littoral zone, water quality is maintained because sediments and pollutants are trapped before entering the lake and the energy of wave action is absorbed or dissipated minimizing erosion.
Lakeshore (Littoral Zone) Plant Life
Characteristically, the littoral zone is occupied by rooted plants such as water lilies, rushes, and sedges. Plants and animals found here vary with water depth. Pond lilies colonize the deeper water while emergent plants such as pickerelweed, arrowheads, bulrushes, and cattails grow in shallow water. Within the sheltering beds of emergent plants, animal life is abundant. The aquatic plants growing in the littoral zones play an important role in maintaining water quality by absorbing phosphorus, nitrogen, and other nutrients in the water that could otherwise cause nuisance or harmful algal blooms. Furthermore, this diversity of plant life, along with the microhabitats provided by sand, gravel, rock, and organic substates are essential for all lake-dwelling species, especially invertebrates such as insects, crustaceans, mollusks, and snails. Invertebrate larvae and adults inhabit the littoral zone sediments, vegetations, and surface films. These organisms provide the platform for the aquatic food chains in the lake.
This relatively shallow water area is the interface between the adjacent uplands and the open waters of the lake, and as such, contributes significantly to the productivity and overall metabolism of the lake. Michigan's inland lakes support 65 species of fish, 24 species of amphibians, 25 species of reptiles, 87 species of birds, and 19 species of mammals.
In one way or another, the following animals are supported by habitat found in the littoral and nearshore areas of lakes:
- Fish: Aquatic plants provide crucial habitats at different life stages of many fish species. They serve as substrates for eggs and refuges for juvenile fish, as well as provide habitat for species that require plants for their existence.
- Amphibians and Reptiles: They breed and lay their eggs in the shallow, vegetated water. Amphibians and reptiles use shoreline basking sites and terrestrial buffers for feeding and overwintering.
- Birds:
- Shorebirds forage in shallow water for insects, crustaceans, and small fish
- Waterfowl use emergent vegetation for nesting and brood cover, feed on seeds, tubers, and submerged plants
- Raptors hunt from shoreline perches for fish and water birds, and nest in tall trees of snags near water
- Songbirds nest in shrub and tree belts, exploit insect outbreaks, and use shoreline corridors during migration
Loss of natural vegetation threatens Michigan lakes
-Michigan Natural Shoreline Partnership
50% of Michigan inland lakes have poor nearshore habitat
- National Lake Assessment Study
63% of Lake Leelanau properties have poor nearshore habitat
- 2017 Aerial Drone Shoreline Survey Analysis by Freshwater Solutions
Lakeshores are biodiversity hotspots where a mosaic of physical features and biological communities converge. From tiny invertebrates living in sediment to raptors scanning open water, countless species rely on the shoreline’s varied habitats for life-cycle needs.
Protecting and restoring shoreline processes and habitats preserves these essential functions---benefiting wildlife, water quality, and people who depend on healthy lakes. According to the National Lake Assessment study, poor lake shore habitat is the biggest problem facing our nation’s lakes. Lakeshore homeowners can have huge impacts on the lake shore ecosystem and therefore have a huge responsibility to protect it.
Embrace Your Lakeshore Ecosystem
Everyone can do their part to protect Lake Leelanau from their shoreline, and the Lake Leelanau Lake Association is here to help you. If you want to protect our lake and do something to improve your lakefront property but don’t know where to start, sign up for a complimentary shoreline consultation with our trained Shoreline Ambassadors.
Schedule a Shoreline Consultation
Learn more about the program here, or click below to schedule your own shoreline consultation.
Cover photo courtesy of Mark Bugnaski Photography.
Resources
LLLA's Guide to Native Vegetation for Shorelines (and where to buy native plants)
Michigan Natural Shoreline Partnership Native Plant Guide
Reducing Runoff and Erosion from your Waterfront Property
Native Plant Nurseries
Zimmerman Landscaping - Traverse City
Four Seasons Nursery - Traverse City
Black Cap Nursery - Onekema
Graystone Nursery - Honor
Prairie Nursery Catalog - Wisconsin - they have a great selection, ships on your schedule and the catalog is a wealth of information.
References
Understanding lakeshore ecosystems Part I, Part II, and Part III by Dixie Sandborn
Natural Shoreline Landscapes for Michigan Inland Lakes-A Property Owner's Guide $25