South Fox Island mapped-dune, forest, vegetation, wetland, and wildlife evidence

Why this matters

This closes the largest current ecology gap in the Fox Islands. EGLE’s mapped dune complex 75 encompasses the entirety of South Fox Island and documents a large, connected dune–forest–wetland system rather than treating the island as an undifferentiated wildlife-table entry.

The complex covers approximately 3,430 acres, reaches a maximum dune height of 365.9 feet, has 11.6 miles of shore, and received a 100 percent dune-health score. The report identifies eight natural-community occurrences: three open dunes, an interdunal wetland, boreal forest, mesic northern forest, sand and gravel beach, and clay bluff. It also records eight rare-plant and seven rare-animal element occurrences.

Geology and coastal processes

South Fox contains high west-facing parabolic barrier dunes, lower eastern dunes and beach ridges, perched dunes, steep clay bluffs, blowouts, ghost forests, and interdunal depressions. The report describes much of the western shore as one of the world’s strongest examples of a perched-dune system. Natural processes include erosion, seepage, landslides, sand burial, blowout formation, accretion, and large-scale dune movement. The interior dunes are largely stabilized by forest succession while remaining morphologically intact.

Forest composition and tree history

The boreal forest occurrence is dominated by uneven-aged northern white-cedar on steep bluffs, blowouts, and parabolic dunes. Mountain maple, balsam fir, round-leaved dogwood, choke cherry, and red elderberry form a dense subcanopy. Several western cedars were estimated at more than 400 years old; a younger cedar cohort near northern landslides included trees around 130 years old. Windthrow, senescence, dune erosion, snags, and coarse woody debris structure the forest. Historic selective logging is visible, and introduced deer have caused localized browse-related reduction in the flora.

The mesic northern forest occurs in five sections on gentler inland dune slopes. Sugar maple dominates a mature to old-growth canopy with American beech, white-cedar, paper birch, basswood, red oak, beaked hazelnut, alternate-leaved dogwood, red elderberry, ironwood, and white ash. The 2021 survey notes a robust herbaceous layer with 34 documented herbs. Emerald ash borer and beech bark disease have altered canopy composition, while coarse woody debris, windthrow, and senescence remain important structural processes.

Vegetation, wetlands, and shoreline

The principal western open-dune occurrence includes marram grass, sand reed grass, Gillman’s goldenrod, hairy puccoon, white camas, beach pea, wheat grass, bearberry, sand cherry, creeping juniper, white-cedar, and soapberry. A dead white-cedar in an old blowout was aged at 300 years, documenting the long-term movement of the boreal/open-dune boundary.

The eastern open-dune occurrence supports marram grass, sand reed grass, starry false Solomon-seal, sand coreopsis, Gillman’s goldenrod, sand cherry, creeping juniper, wild rose, white-cedar, paper birch, red-osier, balsam fir, and soapberry. Monarchs were observed during the 2021 survey.

The interdunal wetland occurrence occupies shallow depressions on the southern tip and eastern dunes. It includes Baltic rush, Juncus brachycaudatus, Juncus dudleyi, beak-rush, golden-seeded spike-rush, native reed, Carex viridula, sand cherry, and white-cedar. All wetlands held standing water during the August 2021 survey. The assemblage suggests calcareous conditions, and wetland size varies with Great Lakes water levels. Narrow- leaved cattail, off-road vehicles, and horse recreation are documented management concerns.

The sand and gravel beach is a dynamic Lake Michigan shoreline community with variegated scouring rush, sand reed grass, wild wormwood, white-cedar, soapberry, and paper birch. High-water years left vegetation sparse. The clay bluff supports Gillman’s goldenrod, sand reed grass, wheat grass, white camas, sand coreopsis, paper birch, soapberry, creeping juniper, and bearberry in sparse cover shaped by seepage, erosion, and landslides.

Animals and birds

The EGLE descriptions identify South Fox’s dune, beach, bluff, forest, and wetland mosaic as habitat for Fowler’s toad, eastern hognose snake, spider wasps, wolf spiders, antlions, dragonflies, damselflies, midges, shorebirds, waterfowl, neotropical migrant songbirds, and bats. Dense animal tracks and abundant toads were recorded at the interdunal wetlands, and monarchs were observed in the eastern open dunes.

These are habitat-function statements and survey observations, not a complete South Fox fauna inventory. They should remain separate from the GBIF public observation index and the MDNR distribution-table records.

Mapping and evidence limits

The generated GeoJSON contains nine representative occurrence points printed in the report. It does not represent natural-community boundaries. The layer should be used with the seven-island NLCD land-cover and tree-canopy rasters, the soil and geology layers, the North Fox mapped-dune index, and the Fox Island historical corpus.

The source was not a 2025 field survey, and its ownership/access statements should not replace current parcel records. The next useful refinement is to obtain or reconstruct the underlying MNFI occurrence polygons and connect the rare-element counts to public records without exposing sensitive locations.

Added 3 August 2026. Recent changes