The Prairie Coteau Complex IBA consists of six separate areas lying within the Prairie Pothole and Eastern Tallgrass Prairie Bird Conservation Regions. The IBA is located in the southwest portion of the state, predominantly within Pipestone County but with portions in Yellow Medicine, Lincoln, Murray and Rock Counties. The six areas that make up the IBA while not contiguous, are ecologically similar and emphasize the remaining prairie and grassland bird habitat in a landscape that is quite fractured and dominated by agriculture. The criteria used to select these areas is based on bird data collected by the USFWS and MN DNR as well as native prairie habitat delineation work that has been done by the MN DNR and Nature Conservancy (TNC).
This IBA is accessible via I-90 on the southern end, with U.S. Hwy 75 running through or near all six sections. From the south, the first section is located near Luverne, MN and includes Blue Mounds State Park. The next section is about 8 miles north near Edgerton and Chandler, MN and can be reached from State Hwy 268. Just to the north, the third section begins and includes Holland, MN and is accessible from State Hwys 30 and 23 from Pipestone, MN. The largest section stretches about 20 miles from the South Dakota border northeast past Lake Benton and is bisected by U.S. Highways 75 and 14. The remaining two sections lie just to the north and sit on the South Dakota border.
Historically, western Minnesota was predominantly Northern Tallgrass Prairie interspersed with countless wetlands. This prairie pothole area produced mallards, teal, canvasbacks, other waterfowl and water-dependent birds by the millions. Many wetlands have since been drained and tallgrass prairie is now one of North America's rarest habitats. In this area most of this habitat is found on federally owned Wildlife Production Areas (WPAs), State owned Wildlife Management Areas (WMAs), Nature Conservancy (TNC) lands, and some private land. As a complex, this IBA contains 22 WMAs, 6 WPAs, 2 Scientific and Natural Areas, 1 State Park and 1 TNC preserve. There are also a variety of privately owned lands, some of which that are currently participating in conservation easement programs such as Reinvest in Minnesota and the Conservation Reserve Program. Wildlife Management Areas (5,501 acres):
The 22 WMAs that are scattered throughout this IBA range in size from 12 to 638 acres, with the majority ranging between 100 and 300 acres. In general these WMAs consist of native prairie remnants, restored prairie, grassland, wetlands, some woody vegetation and cultivated agriculture, which is typically used as food plots for wildlife. Hunting is allowed on most WMAs, though there are some restrictions for ecologically sensitive areas or privately owned lands within the WMA. Waterfowl Production Areas (639 acres):
There are six WPAs within this IBA which are characterized by diverse habitat types such as native prairie, wetlands, oak woodlands, and formerly farmed lands. The USFWS typically conducts prairie and wetland restorations on WPAs to improve the landscape for wildlife with a focus on migratory and grassland birds. WPAs are Federal lands and open to the public for bird watching, hunting and fishing. Scientific and Natural Areas (882 acres):
Mound Spring Prairie SNA - is a 453 acre unit located on the South Dakota border in yellow Medicine County. This SNA preserves one of the largest remaining native prairie complexes in Southwestern MN. One hundred and four bird species have been recorded at this site including 16 species of sparrow, Loggerhead Shrikes, Western Kingbirds and Horned Larks.
The Prairie Coteau SNA ? is a 329 acre site with typical glacial moraine topography with some steep slopes and valleys. The vegetation is a mix of native and restored prairie, including two rare plant communities, the southwest dry hill prairie and the dry sand-gravel prairie. On the southeast boarder as well as in the southwest corner of the unit is a large willow marsh and small stock pond. Sixty-three bird species have been recorded at the site including Northern Harriers and Swainson?s Hawks. Twelve species of sparrow were also documented at this site.
Minnesota State Park (1,826 acres):
Blue Mounds State Park is located in the Southern most portion of the IBA and is characterized by abundant rock outcroppings which prevented this area from being plowed for agriculture by early settlers. This State Park has a composite bird list of 242 species, some of which are very rare sightings such as the Lazuli Bunting and Black-headed Grosbeak which are typically more western species.
The Nature Conservancy (1,368 acres):
Hole-in-the-Mountain Preserve is situated on a steep valley along the outer edge of the Prairie Coteau. The prairie valley is the headwaters of Flandreau Creek, which runs in a southwesterly direction toward the Big Sioux River.
The Prairie Coteau Complex IBA focuses on prairie, grassland and marsh birds because the availability of quality habitats for these species are becoming less common in the southwest region of the state. This IBA hosts a number of species of conservation concern including: Henslow's Sparrow, Burrowing Owl and Chestnut-collared Longspur (endangered); Horned Grebe, Wilson's Phalarope and Loggerhead Shrike (threatened); and Marbled Godwit, Franklin's Gull, Forster's Tern, Short-eared Owl, and Nelson's Sparrow (species of special concern). In total, 251 species have been observed here including 71 Species of Greatest Conservation Need. Likewise, this IBA supports assemblages of species that represent high quality, rare habitat types such as sedge wetlands and native prairie.
MN-1e. Species Diversity
IBA criteria for species diversity calls for the site to support at least 12 species of shorebirds; at least 23 have been observed within the Prairie Coteau Complex:
MN-2a. Endangered, threatened or species of special concern
Eight federally listed species have been recorded within this IBA complex:
Data for the Forster?s Tern and Burrowing Owl are considered in a historical perspective as they were both documented prior to 1990. The Forster?s tern was recorded in the Natural Heritage Database (last record 1976). Likewise, the most recent records for Burrowing Owls were collected during research that was conducted from 1985-1987 (M. Martell 1990, Martell et. al. 2001).
MN-2b. Species of conservation concern
Thirty-nine Minnesota species of conservation concern have been observed within the Prairie Coteau IBA (Appendix 1). Three species that have been seen reliably and have consistent numbers are the Upland Sandpiper (79 in 2009), Dickcissel (69 in 2006), and Bobolink (49 in 2006, and 78 in 2009).
MN-3. Rare, threatened, or unique habitat assemblages
The Prairie Coteau IBA has 7 of the 9 species representative of sedge wetland (rich fen, poor fen, wet meadow) habitat type:
Le Conte's Sparrow
This IBA has 25 of the 28 species representative for native prairie (dry, mesic, wet prairie):
Le Conte's Sparrow
The major threat to this area, which is directly related to most of the threats on the list, is the expiration of Conservation Reserve Program lands in the 2012 Farm Bill. This introduces uncertainty as to how these lands will be managed, with the likely reality being that private lands once managed for wildlife will return to agriculture, biomass production and grazed lands. With the conversion of prairie and wetlands back into agriculture comes the drainage of marshes, increased use of pesticides and potential for over grazing, all of which negatively impact the remaining remnants of native prairie and wetland habitats.
This region was historically covered by native prairie with patches of interspersed wetlands, predominately shaped by climate, grazing and fire. Since the early 1900s the native tallgrass prairie has been converted predominately into agricultural fields. Fire suppression practices have also altered the landscape by allowing prairie succession and reducing the diversity of native grasses that once thrived here. Likewise, long duration, high intensity grazing regimes have impacted the prairie, creating grasslands that are less diverse and more susceptible to erosion and weed infestation.
Wind development is another growing industry in this area that has the potential to impact grassland birds and transform the landscape.