Wetlands & Wildlife Corridors

Shoreline, Septic & Stormwater

How wetlands keep lakes clear and how land connections let wildlife move safely—plus simple steps property owners and communities can take.

Why Wetlands Matter to Your Lake

Wetland Types (Plain Language)

Bogs/Fens

Peat-forming, slow-changing; store carbon and release very clear, low-nutrient water

Marshes

Emergent plants (cattails, sedges); great for nutrient uptake and waterfowl

Swamps

Shrub/tree-dominated; provide shade, woody debris, and flood storage

Shallow Open Water

Pond-like zones that connect to streams or lakes

Wildlife Corridors—What and Why

Definition

Strips or networks of habitat that let animals move between feeding, nesting, and wintering areas

Why It Matters

Movement keeps populations healthy, spreads pollination, and lets species adjust to drought, heat, and high water

Signs of Corridors on Your Property

  • Natural lines: Stream edges, wetland fringes, hedgerows, and treed fencelines
  • Travel evidence: Tracks on sand/mud, well-worn paths, crossing points along culverts/bridges
  • Seasonal use: Spring amphibian migrations, fall bird flights, and summer pollinator routes

Practical Actions for Landowners

  • Keep a vegetated buffer (10–35 ft or more) around wetlands and ditches
  • Leave downed wood where safe; it builds structure for amphibians and birds
  • Dim and direct lights: Use warm-tone, fully shielded fixtures; reduce light spill into corridors
  • Fence smart: Avoid continuous solid fencing across stream edges; leave wildlife-friendly gaps where safe
  • Pets & timing: Keep dogs leashed near wetlands in spring when nests and metamorphs are vulnerable

Road, Driveway & Trail Crossings

  • Right-Sized Culverts

    Match natural channel width; set slightly below bed grade to keep a natural bottom

  • Aquatic Organism Passage

    Use arched/box culverts or embedded round culverts with natural substrate

  • Hydraulic Checks

    Ensure capacity for big storms; add overflow relief and stable inlets/outlets

  • Avoid Barriers

    High outlet drops and perched culverts block fish and amphibians

Beavers: Neighbors & Water Managers

Benefits

Raise local water tables, expand wetlands, trap sediment, and create habitat

Conflicts & Options

Use flow devices ("beaver deceivers") to control levels at problem culverts; trap/remove only when devices fail and rules allow

Cold-Climate & Seasonal Notes

  • Spring thaw: Wetlands take the brunt of meltwater—keep plowed snow and sand piles out of wetland edges
  • Summer drought: Corridors concentrate wildlife near remaining water; avoid heavy work in riparian areas
  • Fall drawdown: Natural low levels expose soils; avoid rutting and compaction

Restoration & Enhancement (Right-Sized Steps)

  • Un-ditch where feasible: Break up straight ditches with meanders and shallow shelves
  • Plug small cuts that drain wetlands (with approvals); encourage shallow pools
  • Re-plant native edges: Sedges, rushes, shrubs, and trees matched to moisture zone
  • Remove fill and invasives selectively; re-establish hydric soils and microtopography

Permits & Coordination

Activities in or near wetlands often need permits. Sketch your idea, note distances to water, and check early with local and state programs.

Coordinate with road authorities on crossing upgrades; combine projects to share costs.

Monitoring & Stewardship (Simple)

  • Seasonal photo points: Spring high water, mid-summer, fall
  • Track crossings: Note blocked culverts, perched outlets, or erosion; report issues
  • Wildlife notes: First frog calls, turtle nesting dates, common tracks; consistent notes reveal patterns

Myths—And Better Takes

  • "Wetlands are just swamps to drain"

    Better take: They are the lake's filter and floodplain—draining shifts problems downstream

  • "Culverts only need to pass baseflow"

    Better take: Undersized pipes cause road washouts and fish barriers

  • "Thick shrubs mean neglect"

    Better take: Shrub swamps stabilize banks and host nesting birds

Quick Worksheet (Plan & Protect)

Wetland/corridor areas on property: _________________________________
Buffer width today → target: ______ ft → ______ ft
Crossings needing attention: _________________________________
Lighting fixes (fixtures/aim/timer): _________________________________
Native plants to add (by zone): _________________________________

Bottom Line

Wetlands and the green connections between them keep lakes clear and wildlife thriving. Protect buffers, fix crossings, and plan projects with water and movement in mind.

Related Topics

Key Takeaways

  • Wetlands filter nutrients and slow floods
  • Wildlife corridors keep populations healthy
  • Maintain 10-35 ft vegetated buffers
  • Size culverts to natural channel width
  • Beavers can be managed with flow devices
  • Most wetland work requires permits

Buffer Width Guide

Minimum (10 ft):
Better than nothing; catches some runoff
Good (25 ft):
Effective for most properties
Excellent (35+ ft):
Maximum water quality and habitat benefits

Culvert Checklist

  • ☐ Matches natural channel width
  • ☐ Set below bed grade
  • ☐ Natural substrate inside
  • ☐ No perched outlet
  • ☐ Sized for peak storm flows

Wildlife Timing

Sensitive periods:

  • Spring: Amphibian migration & nesting
  • Summer: Fledgling birds learning to fly
  • Fall: Migration corridors active

Need Wetland Guidance?

Contact your local conservation district, DNR wetland specialist, or Soil & Water Conservation District for site-specific advice and permit requirements.

Find Resources