Northeast Wisconsin Important Bird Areas

Bay Beach Wildlife Sanctuary - Green Bay

Bay Beach Wildlife Sanctuary - Green Bay

Bay Beach Wildlife Sanctuary - Green Bay

Canada Warbler.  Bay Beach Wildlife Sanctuary during May migration.  Photo: Kari Hagenow.

The Bay Beach Wildlife Sanctuary is a 600+ acre urban wildlife refuge featuring live animal exhibits, educational displays, miles of hiking/skiing trails and various wildlife viewing opportunities.    To bird the Sanctuary is to experience a premiere “bird funnel.” The adjacent bay sweeps significant concentrations of landbirds through the property each spring and fall. Over 260 species have been documented at the Sanctuary, including thirty-three species of warblers.


Due to diverse habitats, Bay Beach can add a wide variety of bird species to your list in a relatively short visit in any season. Egrets, herons, pelicans, nesting Bald Eagles, Osprey, owls, and waterfowl are just part of the active wildlife community.  Most birds can be observed from the hard-surfaced trails and floating boardwalk in and around the main buildings. More adventurous birders can walk the six miles of trails. 

Point Beach State Forest - Two Rivers

Bay Beach Wildlife Sanctuary - Green Bay

Bay Beach Wildlife Sanctuary - Green Bay

Point Beach State Forest.  Photo: Kari Hagenow.

This site harbors ridge-and-swale topography and a variety of nature communities.  Deciduous forest, hardwood swamp, lowland conifer forest, open dunes with rare dune plants, sand beach, shoals and open water can all be found here.  


Point Beach State Forest contains a large block of undeveloped Lake Michigan shoreline and provides important nesting and migration habitat for a variety of birds.  Eastern wood-pewee, wood thrush, hooded warbler, ovenbird, and American redstart all breed here, as do small numbers of northern species such as Blackburnian warbler and Canada warbler.  Large numbers of diving ducks, loons, and grebes congregate in the offshore waters, especially in the fall, and tens of thousands of landbirds and raptors use the area during both spring and fall migration.

Mink River Estuary & Newport State Park - Ellison Bay

Green Bay West Shore Wetlands - Brown, Oconto & Marinette Counties

Green Bay West Shore Wetlands - Brown, Oconto & Marinette Counties

Interior marsh at the Mink River State Natural Area.  Photo: Kari Hagenow

Extensive, undeveloped shorelines and a variety of habitats characteristic of the shores of Lake Michigan make this an ecologically rich and important site.  Habitats include open waters, sand and cobblestone beach, dunes, coastal wetlands composed of sedges, cattail, and bur-reed, and swamp conifer, mesic, and boreal forests.  


Many priority wetland birds breed here including osprey, American bittern, Virginia rail, sedge wren, and the rare yellow rail.  Forest breeders include at least 13 species of warblers and other passerines, some, like golden-crowned kinglet and Cape May warbler, at or near the southern limit of their ranges in the state.  The terrestrial habitats at this site also provide important stopover habitat for migrating birds, and large flocks of diving ducks utilize the open waters of Lake Michigan in the winter.  The  Mink River Estuary is owned and managed by The Nature Conservancy and Newport State Park by the Wisconsin Department of Natural Resources.

Green Bay West Shore Wetlands - Brown, Oconto & Marinette Counties

Green Bay West Shore Wetlands - Brown, Oconto & Marinette Counties

Green Bay West Shore Wetlands - Brown, Oconto & Marinette Counties

Sensiba marsh, part of the Green Bay West Shore Wetlands.  Photo: Kari Hagenow.

This Important Bird Area consists of a series of sites along the west shore of Green Bay, including the County Line Swamp south of Peshtigo, owned by Marinette and Oconto County Forests; nine units of the Green Bay West Shores State Wildlife Area; a DOT mitigation site; a State Natural Area; a Brown County park; and a City of Green Bay park.  These areas contain significant tracts of both open and forested wetlands, including emergent marsh, sedge meadow, shrub swamp, and lowland and upland hardwood forest.   


This is a significant wetland site for both migrating and breeding birds.  High priority breeders include osprey, red-shouldered hawk, American black duck, American bittern, American woodcock, black-billed cuckoo, sedge wren, and golden-winged warbler.  Waterfowl, shorebirds, and landbirds use the site extensively during migration.  Waterbirds including Caspian, common, and Forster’s terns and American white pelicans, use this site for foraging.

Door-Kewaunee Lakeshore Migration Corridor

Woodland Dunes Nature Preserve - Two Rivers

Woodland Dunes Nature Preserve - Two Rivers

Kewaunee harbor and lighthouse.  Photo: Kari Hagenow.

This Important Bird Area encompasses the open waters of Lake Michigan, up to ten miles out from the shore, and extends from the southern edge of Whitefish Dunes-Shivering Sands Important Bird Area in Door County, south through Kewaunee County to the northern border of Point Beach State Forest Important Bird Area in Manitowoc County.  


Beneath the waters are structures such as reefs, underwater sandbars, and bedrock shelves used by diving ducks during foraging.  Large numbers of wintering ducks utilize these offshore waters.  Recent aerial surveys have documented particularly large concentrations of Long-tailed Duck, Red-breasted Merganser, and Bufflehead within the area.

Woodland Dunes Nature Preserve - Two Rivers

Woodland Dunes Nature Preserve - Two Rivers

Woodland Dunes Nature Preserve - Two Rivers

Yellow warbler at Woodland Dunes Nature Center.  Photo: Kari Hagenow.

This 1,500 acre preserve is part of a ridge-and-swale complex adjacent to Lake Michigan between Manitowoc and Two Rivers.  It contains a diversity of high-quality habitats that include upland and lowland hardwood and coniferous forest, shrub swamp, sedge meadows, cattail marsh, and wet and dry meadows.  Facilities include hiking trails, boardwalk, observation platforms, and an interpretive center.  


With its high-quality habitats adjacent to the Lake Michigan flyway, Woodland Dunes attracts thousands of migrating birds.  

Many species stay to breed here including osprey, black-billed cuckoo, marsh wren, veery, ovenbird, and mourning warbler, as well as species that are typically found much further north such as black-throated green warblers, Magnolia warbler, and black-and-white warbler.  

Whitefish Dunes-Shivering Sands - Door County

Toft Point-Ridges Sanctuary-Mud Lake - Baileys Harbor

Toft Point-Ridges Sanctuary-Mud Lake - Baileys Harbor

Shivering Sands Preserve.  Photo: Kari Hagenow

This site on the Door Peninsula encompasses Whitefish Dunes State Park, Cave Point County Park, and lands owned by The Nature Conservancy in their Shivering Sands Preserve.  A variety of habitats are present here, ranging from a high-quality beach and dune complex to cedar swamps and upland deciduous mixed forests.  It also includes the open waters of Lake Michigan.  


The site provides breeding habitat for a number of species, including Black-throated Blue Warbler, Blackburnian Warbler, and Canada Warbler.  More than 110 species of birds ahve been documented to breed here.  It also receives heavy use as a stopover site for neotropical migrants, raptors, and short-distance migrants moving along the Lake Michigan shoreline and flyway.  Large flocks of diving ducks utilize the open waters of Lake Michigan in the winter.

Toft Point-Ridges Sanctuary-Mud Lake - Baileys Harbor

Toft Point-Ridges Sanctuary-Mud Lake - Baileys Harbor

Toft Point-Ridges Sanctuary-Mud Lake - Baileys Harbor

Toft Point State Natural Area.  Photo: Kari Hagenow

This site includes Toft Point State Natural Area, The Ridges Sanctuary, and Mud Lake State Wildlife Area.  It features unique dune-swale topography and a variety of high-quality, habitats including boreal forest, mixed conifer-hardwood forest, alder thicket, coastal wetlands and bays, and open waters of Lake Michigan.  The Ridges Sanctuary is a good starting point for birding this area as it offers  ADA-accessible and interpretive trails, a nature center, and information about the local area.


Osprey, Bald Eagle, American Bittern, Yellow-bellied Flycatcher, Blue-headed Vireo, and seventeen species of warblers have been documented breeding here.  Caspian and common terns forage along the shorelines and waterfowl and landbirds use the site during migration.  Large flocks of diving ducks also utilize the open waters of Lake Michigan in the winter months.

Lower Green Bay Islands

Lower Wolf River Bottoms - Shawano, Outagamie, Waupaca, & Winnebago Counties

Lower Wolf River Bottoms - Shawano, Outagamie, Waupaca, & Winnebago Counties

Birding the Cat Island Chain within Lower Green Bay.  Photo: Kari Hagenow

Lower Green Bay Islands and the Bay Beach Wildlife Sanctuary comprise one Important Bird Area, however are separated on this site fore reasons of accessibility.  The Lower Green Bay Islands include those islands that are in the southernmost portion of the Bay, including Cat Island and Lone Tree Island.  The islands are mostly gravel with sparse, scattered trees and shrubs.  Access to Cat Island is limited and access beyond gates must be requested from the Cat Island Advisory Committee.  


The islands provide nesting habitat for colonial waterbirds including American White Pelican, Double-crested Cormorant, and the only great egret colony in Green Bay on Cat Island.  Common terns and snowy egrets have also nested here in the past.  The restored Cat Island is also a host to nesting Piping Plovers - starting with the first pair to breed in Green Bay in 75 years and growing.  

Lower Wolf River Bottoms - Shawano, Outagamie, Waupaca, & Winnebago Counties

Lower Wolf River Bottoms - Shawano, Outagamie, Waupaca, & Winnebago Counties

Lower Wolf River Bottoms - Shawano, Outagamie, Waupaca, & Winnebago Counties

Floodplain forests of the Lower Wolf River Bottoms.  Photo: Wisconsin DNR (dnr.wi.gov)

The site encompasses the ~100 miles of the Wolf River below the Shawano dam as it flows south to Lake Poygan.  Numerous state properties are located within this IBA.  It is a vast area of open and forested wetlands, sometimes occurring in extensive tracts, both along the Wolf and its mail tributaries (the Embarass, Shioc, Little Wolf, Waupaca, and Rat Rivers).  The floodplain forests here are the largest and most intact in all of eastern Wisconsin.  A wealth of other habitat types are found here including sedge meadow, open bog, restored prairie, and more.


This IBA provides breeding habitat for many priority species including Red-shouldered Hawk, Northern Harrier, Least and American Bitterns, Yellow-crowned Night-heron, Virginia Rail, Black Tern, Black-billed Cuckoo, Yellow-billed Cuckoo, Least Flycatcher, Prothonotary Warbler, Cerulean Warbler and more.  Tens of thousands of Tundra Swans, Canada Geese, and waterfowl, as well as 20 species of shorebirds, use the wetlands and flooded fields here during migration.

Waupee Lake - Oconto County

Lower Peshtigo River - Marinette and Oconto Counties

Lower Peshtigo River - Marinette and Oconto Counties

Waupee Lake Swamp State Natural Area.  Photo: Joshua Mayer (flickr)

This site on the Chequamegon-Nicolet National Forest features a mosaic of forest, shrub, and wetland habitats.  There are upland forests of pine, oaks, northern hardwoods, and mixed coniferous-deciduous species, substantial areas of shrubby edges and semi-open woodland, swamp hardwoods and conifers, shrub swamps, emergent wetlands, and small lakes.


A diverse group of birds breeds here including shrub species such as the Black-billed Cuckoo, Alder Flycatcher, Brown Thrasher, Golden-winged Warbler, Mourning Warbler, and Field Sparrow.  Upland deciduous forest species like Red-shouldered Hawk, Least Flycatcher, and Wood Thrush, and birds of lowland forests, including Olive-sided Flycatcher, Yellow-bellied Flycatcher, and Canada Warbler can also be found breeding here.

Lower Peshtigo River - Marinette and Oconto Counties

Lower Peshtigo River - Marinette and Oconto Counties

Lower Peshtigo River - Marinette and Oconto Counties

Peshtigo River State Forest.  Photo: Wisconsin DNR (dnr.wi.gov)

This Important Bird Area encompasses state-owned lands along the Peshtigo River below the Town of Peshtigo, including the Peshtigo Harbor Unit of the Green Bay West Shores State Wildlife Area, Bloch Oxbow and Pines State Natural Area, and others.  The site contains some of the most significant riparian and wetland habitats in the Green Bay ecosystem, including extensive floodplain forest, sedge meadow, emergent marsh, and sandy uplands featuring northern-dry mesic forest and semi-open grasslands.


A long list of priority breeding birds occur here including red-shouldered Hawk, osprey, northern harrier, american bittern, Forster's tern, golden-winged warbler, grasshopper sparrow, field sparrow, bobolink, and eastern meadowlark.  Yellow rails have been documented here.  Colonial waterbirds such as Caspian tern and great egret often forage here as well.