Willow Slough Fish and Wildlife Area is located in rural northwestern Indiana adjacent to the state?s border with Illinois. Encompassing almost 10,000 acres, the property is one of the largest owned and managed by Indiana?s Fish and Wildlife Division.
The area was greatly altered by drainage and agriculture in the 1800s and early 1900s before being purchased by IDNR in 1949 for wildlife conservation. An 18-acre remnant of the former slough still exists on the property, although the 1500-acre J. C. Murphey Lake and adjacent Pogue Marsh are the more productive areas for migrant and nesting birds now. The property also comprises several natural habitats typical of the sandy conditions found within Newton County, including savanna and pin oak flats.
A significant feature of the Willow Slough FWA is its proximity to other Important Bird Areas. The property is immediately bordered by the Nature Conservancy?s Kankakee Sands Project to the north and Illinois? Iroquois State Wildlife Area to west. These three IBAs combined encompass nearly 20,000 acres of critical bird habitat within the Grand Prairie Natural Region for nesting grassland, savanna, and marsh land species.
Because of the property?s large size and the mosaic of habitats which its boundaries encompass, Willow Slough FWA supports some of the most diverse nesting and migratory avian populations of any Indiana Important Bird Area.
One of the main components of Willow Slough?s fecundity for migratory birds is the 1500-acre J. C. Murphey Lake and its associated marshland habitats. During late March and early April, these areas support some of the most abundant waterfowl populations in the state. Peak daily counts of Aythya and Anas species alone often total over 2,000 individuals during these weeks. The marshes and periphery vegetation of the lake also attract flocks of Rusty Blackbirds during early spring, which is a passerine declining at a hazardous rate throughout North America.
Located on the north side of J. C. Murphey Lake, Pogue?s Marsh is an important locale for nesting and migrant marsh birds. At least five species listed as endangered in Indiana are suspected of breeding within this section of Willow Slough over the last few years ? Least Bittern, Common Moorhen, Virginia Rail, Sandhill Crane, and Marsh Wren.
Also, to the north of J. C. Murphey Lake and its marshes, several hundred acres of upland habitat is maintained as early successional and shrubland habitat. These areas have become a critical location in northwestern Indiana for several WatchList and state-endangered species. Willow Flycatcher and Bell?s Vireo breed in such brushy habitats, and, in years following prescribed fire treatments, Sedge Wren is also a nester within some plots.
The southern portion of Willow Slough comprises oak savanna and pin oaks flats, as well as smaller areas of sand prairie and sedge meadow. Conservation-priority species such as Whip-poor-will, Red-headed Woodpecker, and Wood Thrush are common within the wooded habitats and edges. Interestingly, these areas have also attracted more southerly nesting species, including Yellow-throated Warbler, Kentucky Warbler, and Summer Tanager, during recent years.