Minnesota's shorelines are being developed at a record pace. Buildings and lawns that replace natural shores have adverse impacts on wildlife and water quality. A natural shoreline is more than an aesthetic buffer for the lake; it is a complex ecosystem that provides habitat for a diversity of wildlife and protects water quality for the entire lake.
The following research summaries highlight the value of natural shorelines for fish, wildlife, and water quality:
When a lakeshore becomes developed:
- There is a 30% reduction in native tree and shrub canopy
- There is a 66% reduction in shoreline vegetation
Statewide, Minnesota has lost 20-28% of its emergent and floating-leaf vegetation in our lakes.
Elias and Meyer. WETLANDS 23:4 (2003)
Radomski and Goeman, MNDNR 2001
Songbirds
Surveys show just as many birds on developed lake shores as undeveloped shore. But what kind of birds are they? Uncommon songbirds, like warblers (photo left) and vireos, were primarily found along undeveloped lakes. Many of these songbirds winter in the tropics, and some are considered "species of special concern" because of declining numbers. Common birds, like English sparrows and blue jays (photo below), were more abundant on developed lakes. Research indicates that continued lake shore habitat changes will place uncommon songbirds at greater risk.
Lindsay et al. Biological Conservation 107 (2002) 1-11
Frogs
A Wisconsin survey of green frogs found the more homes per mile the fewer the green frogs.
If you are interested in frogs and toads consider volunteering for the Minnesota Frog & Toad Calling Survey to learn where, when, and how these citizen surveys take place.
Meyer et al. 1997, Wisconsin DNR
Fish
Research in Minnesota lakes has demonstrated that Black Crappie and Largemouth Bass may be affected by shoreline development. Crappies and bass both prefer to spawn near undeveloped shoreline, particularly if hardstem bulrush is present.
Reed, J. R. and D.L Pereira. Relationships between shoreline development and nest site selection by black crappie and largemouth bass. North American Journal of Fisheries Management (2009). Volume: 29, Issue: Table 1, Pages: 943-948
Water quality
Our lakes, wetlands, and streams need healthy shoreline buffers to reduce and filter rainwater runoff that degrade water quality.
Some facts about runoff from a manicured lake lot lawn:
- Runoff can be 5 to 10 times higher than natural shorelines
- Up to 9 times more phosphorus is carried into the lake than from natural shorelines
- Sediment inputs to the lake increase 18 times more than natural shorelines
- Water flowing over lawns also picks up more soil, toxic chemicals/pesticides, pet waste, and other pollutants than natural shorelines
Therefore, it is critical to protect existing natural shoreline as well as restore buffer areas on developed lands.
Margin of Error? Human Influence on Wisconsin Shores, A Production of the Wisconsin Lakes Partnership © 1999 University of Wisconsin
