The Kettle River - St. Croix IBA includes the uppermost reaches of the St. Croix River in Minnesota, along with two major tributaries of the St. Croix: the Kettle River and Lower Tamarack River. The IBA encompasses the relatively contiguous forest-wetland corridor along these important rivers, including numerous wetlands and smaller tributary streams.
Both the St. Croix and Kettle rivers are relatively undeveloped, with heavily-forested valleys. The Kettle River has been designated a State Wild & Scenic River and the St. Croix River is a National Scenic Riverway. The IBA includes approximately 75 kilometers of the St. Croix River upstream (north) of Wild River State Park, and the lower 57 kilometers of the Kettle River (river miles 0 - 36). Another important tributary of the St. Croix, the Lower Tamarack River, flows through the northeastern portion of the IBA. The Snake River enters the St. Croix River in the southern portion of the IBA. However, due to the fragmented, developed nature of much of the lower Snake River corridor, only the lower-most eight-kilometer stretch is included in this IBA.
The St. Croix River forms the border between Minnesota and Wisconsin in Pine and Chisago counties, in east-central Minnesota.The vast majority of the IBA lies within Pine County, with a small portion in northeastern Chisago County. Cities and towns in or near the IBA include Pine City, Hinckley, Sandstone, Askov, and Rutledge in Pine County, and Rush City in Chisago County.
Several large managed areas form the core of this IBA, including St. Croix State Park, Banning State Park, St. Croix State Forest, Chengwatana State Forest, Kettle River Scientific and Natural Area, and St. Croix National Scenic Riverway. Other significant lands within the IBA include the Sandstone Unit of Rice Lake National Wildlife Refuge, three state wildlife management areas (WMA), Pine County forestry lands, and several tracts of the Mille Lacs Indian Reservation.
At least 196 species of birds have been observed within this IBA, including approximately 134 regularly breeding species and another 25 species of unknown breeding regularity. Twenty species of breeding warblers occur in this IBA.
Species of conservation concern (State listed species): Ten state-listed species occur in this IBA, 6 of which probably breed regularly: Louisiana Waterthrush, Red-shouldered Hawk, Cerulean Warbler, Yellow Rail, Trumpeter Swan, Bald Eagle.
Species of conservation concern (non-listed): Forty-seven non-listed species of concern occur in this IBA (listed below). This includes 23 IBA species of concern, and 45 non-listed SGCN (21 species are shared between these categories):
Great Gray Owl
Northern Rough-winged Swallow
Cape May Warbler
Wetlands are a vital component of this IBA. Direct threats to wetlands include loss or degradation of habitat due to agricultural intensification, drainage, urbanization, and succession. Indirect threats may be equally important. Agricultural intensification, extraction industry, urbanization, and pesticides have the potential to negatively impact water quality, either through direct contamination, or increased erosion and sediment load. In particular, many aquatic invertebrates, the primary food source for Louisiana waterthrushes, are quite sensitive to water quality. Increased deposition of sediment in shallow water foraging habitat can also be detrimental to waterthrushes.
The key habitat for important forest bird species in this IBA is mature, closed-canopy deciduous forest along and adjoining rivers and streams. If done improperly, selective logging/cutting in riparian forests and/or on adjacent forested slopes has the potential to negatively impact these rare forest birds. Other priority species, such as American Woodcock, Eastern Whip-poor-will, and Golden-winged Warbler, do require early successional forest, shrubby forest-wetland, and/or forest openings. These species would benefit from forest management practices resulting in younger forest Ideally, this type of management would not occur in areas where it would negatively impact the riparian, mature forest habitat critical to this IBA?s highest priority birds.
Since the St. Croix River Valley is an important corridor for migratory birds, any cellular and wind towers built within or near the IBA have the potential to cause bird mortality.
Invasive and non-native plants/animals are a concern, although the full extent of the threat is not well known. Invasive plants such as reed canary grass, leafy spurge, purple loosestrife, spotted knapweed, buckthorn, and others, are all potential problems in the IBA. Also, oak wilt has recently been discovered in St. Croix State Park.