Rare animals
Find rare and non-game animals.
Rare plants
Learn about plants on the Natural Heritage Working List.
Rare lichens
Discover Wisconsin's lichens.
Natural communities
Explore Wisconsin's natural communities.
Other features
Discover unique resources.
Contact information
For information on Wisconsin's natural communities, contact:
Ryan O'Connor
Natural Heritage Inventory Ecologist

Lake Superior


General natural community overview

Lake Superior is a unique and vast resource of fresh water covering 31,700 square miles. It is the largest freshwater lake in the world by surface area and has 156 miles of coastline in Wisconsin. The lake is primarily cold water with summer maximum water temperatures below 22 degrees Celsius (72 degrees Fahrenheit). Lake Superior is relatively infertile with a historic fish fauna that consisted primarily of lake trout, ciscoes/whitefishes, and sculpins. Warmer and more fertile harbors and bays (e.g., Chequamegon) had a more diverse assemblage of cool and warmwater fishes, especially in the Perch family. Now the biota is dominated by introduced or invasive non-native species. Due to extirpations in other lakes, Lake Superior supports the last remaining Great Lakes population of two whitefish relatives - kiyi and shortjaw cisco.

Lake Superior has not experienced the same levels of development, urbanization, and pollution as the other Great Lakes. Although Lake Superior is the cleanest and most healthy of all the Great Lakes, it is still threatened by toxic pollutants that bioaccumulate in the food chain and persist in the environment. These substances can be transported long distances in the atmosphere and end up in the lake. Local sources contribute pollutants to air and water, adding to the pollutant load entering Lake Superior. Because of its long retention time (191 years), pollutants entering Lake Superior can remain in the lake for over a century before draining to the lower Great Lakes.

Rare animals

Species of Greatest Conservation Need

Wisconsin Wildlife Action Plan graphic

The following Species of Greatest Conservation Need are listed according to their level of association with the natural community type, based on the findings in Wisconsin's 2015 Wildlife Action Plan.

Scores: 3 = high association, 2 = moderate association, and 1 = low association. See the key to association scores for complete definitions.

A Hydroporus Diving BeetleHeterosternuta pulchra2
A Predaceous Diving BeetleIlybius subaeneus2
Hairy-necked Tiger BeetleCicindela hirticollis rhodensis2

Caspian TernHydroprogne caspia3
Common TernSterna hirundo3
Common GoldeneyeBucephala clangula2
Forster's TernSterna forsteri1

Dragonflies and damselfliesScore
Alkali BluetEnallagma clausum3
Zigzag DarnerAeshna sitchensis1

Lake SturgeonAcipenser fulvescens3
Shortjaw CiscoCoregonus zenithicus3
American EelAnguilla rostrata1

Grasshoppers and alliesScore
Lake Huron LocustTrimerotropis huroniana1

Leafhoppers and true bugsScore
A BackswimmerNotonecta borealis2

Big Brown BatEptesicus fuscus1
Little Brown BatMyotis lucifugus1

Mussels and clamsScore
Eastern ElliptioElliptio complanata2

Please see Section 2. Approach and Methods of the Wildlife Action Plan to learn how this information was developed.

Rare plants

The Natural Heritage Inventory has developed scores indicating the degree to which each of Wisconsin's rare plant species is associated with a particular natural community or ecological landscape. This information is similar to that found in the Wildlife Action Plan for animals. As this is a work in progress, we welcome your suggestions and feedback.

Scores: 3 = "significantly associated," 2 = "moderately associated," and 1 = "minimally associated."
Scientific Name Common Name Score
Nuphar microphylla Small Yellow Pond Lily 2


The following Ecological Landscapes have the best opportunities to manage for , based on the Ecological Landscapes of Wisconsin Handbook.

Ecological LandscapeOpportunity
North Central ForestMajor
Superior Coastal PlainMajor

Major (3 on map)
A major opportunity for sustaining the natural community in the Ecological Landscape exists, either because many significant occurrences of the natural community have been recorded in the landscape or major restoration activities are likely to be successful maintaining the community's composition, structure, and ecological function over a longer period of time.

Important (2 on map)
Although the natural community does not occur extensively or commonly in the Ecological Landscape, one to several occurrences do occur and are important in sustaining the community in the state. In some cases, important opportunities may exist because the natural community may be restricted to just one or a few Ecological Landscapes within the state and there may be a lack of opportunities elsewhere.

Present (1 on map)
The natural community occurs in the Ecological Landscape, but better management opportunities appear to exist in other parts of the state.


Wisconsin Wildlife Action Plan graphic

What are conservation actions?

Conservation actions respond to issues or threats, which adversely affect species of greatest conservation need (SGCN) or their habitats. Besides actions such as restoring wetlands or planting resilient tree species in northern communities, research, surveys and monitoring are also among conservation actions described in the WWAP because lack of information can threaten our ability to successfully preserve and care for natural resources.

Threats/issues and conservations actions for natural communities




1996 aerial view of Big Bay Madeline Island looking inland from Lake Superior shows pine-clad barrier beach wetland and inland beach ridge.

Photo by Eric Epstein.


Excellent freshwater estuaries are concentrated along the SW Lake Superior coast. Wetlands associated with these drowned river mouths include marsh, meadow, fens, others.

Photo by Eric Epstein.


Lake Superior estuary, Ashland County.

Photo by Eric Epstein.


Moist, partially shaded sandstone cliff along Lake Superior. Squaw Bay Cliffs, Apostle Islands National Lakeshore.

Photo by Emmet Judziewicz.

Note: photos are provided to illustrate various examples of natural community types. A single photograph cannot represent the range of variability inherent in a given community type. Some of these photos explicitly illustrate unusual and distinctive community variants. The community photo galleries are a work in progress that we will expand and improve in the future.

Last revised: Wednesday, June 16, 2021