Hog Island mapped-dune, forest, shoreline, vegetation, and wildlife evidence

What this adds

The EGLE MDC 101 report adds a current, source-linked ecological description for the northwest side of Hog Island. The 69.5-acre complex is low relief, with a maximum height of 22.6 feet, a 100 percent dune-health score, and an 87.5 percent beach-function score. It is primarily forested, with wooded dune-and-swale topography, Great Lakes marsh, a low foredune, and limestone cobble shore.

The complex is entirely public land within the Beaver Island State Wildlife Research Area and is contiguous with Hog Island’s undeveloped landscape. The report documents zero rare-plant and three rare-animal element occurrences. Two natural-community EOs partially overlap the complex: mesic northern forest (EOID 7843) and limestone cobble shore (EOID 20447).

Forests and tree types

The mesic northern forest consists of mature to old-growth stands estimated at approximately 146–203 years old. Red oak dominates the northern canopy, with white pine, red maple, white ash, and basswood. Near the shoreline, white-cedar and paper birch become locally dominant. Canada yew and red-maple saplings dominate the understory, with mountain maple, balsam fir, red elderberry, Canadian fly honeysuckle, and wild red raspberry.

The ground layer includes star-flower, wild sarsaparilla, bluebead-lily, round-lobed hepatica, spinulose woodfern, and ostrich fern. Large-diameter trees, standing snags, coarse woody debris, pit-and-mound topography, and 80–100 percent overstory cover create important cavity-nester, interior-forest, canopy, and detritus-food-web habitat.

The source associates younger forest pockets with selective logging roughly 150 years ago and a same-cohort species mix with establishment after a stand-leveling fire. No development or immediate anthropogenic threat was identified in the surveyed forest context.

Limestone shore, soils, and hydrology

The limestone cobble shore has wave-worked cobbles, thin calcareous soils, and patchy vegetation grading into conifer-dominated forest. Characteristic plants include Baltic rush, silverweed, Ohio goldenrod, Kalm’s lobelia, bird’s-eye primrose, red-osier, Kalm’s St. John’s-wort, shrubby cinquefoil, stunted white-cedar, and tamarack.

Water-level fluctuation, storm waves, and ice shear remove fine mineral and organic sediment and continually reconfigure the shore. When inundated, it provides nearshore habitat and foraging opportunities for fish, waterfowl, and nearshore birds; exposed cobbles support invertebrates, insects, and herptiles.

Bird and wildlife connectivity

The report connects the mature coastal forest to migrating shorebirds, waterfowl, neotropical migrant songbirds, and bats. The limestone shore and woody debris add nearshore fish, bird, insect, and herptile functions. These are habitat-function statements, not a complete Hog Island species inventory; they should remain distinct from the 1999 survey, MDNR distribution table, and GBIF observation records.

Mapping limits

The generated GeoJSON contains the two representative occurrence points printed in the report. The natural-community EOs extend beyond MDC 101, so the points must not be interpreted as full boundaries. This layer should be combined with NLCD land cover, tree canopy, SSURGO soils, the 1999 Hog Island wetland observations, and the broader archipelago wildlife index.

The EGLE report did not enumerate the three sensitive rare-animal EOs in this public summary. A future step is to seek the underlying MNFI occurrence polygons or an appropriate public-safe species crosswalk without exposing sensitive locations.

Added 3 August 2026. Recent changes