Goose Lake Swamp IBA encompasses a linear complex of wetlands (emergent marsh, rich fen, and wet meadow) and wet prairie sandwiched between roughly parallel beach ridges. Goose Lake proper is a relatively small area of open water and marsh. Uplands adjoining the swamp have aspen parkland vegetation (tallgrass prairie and wet prairie with scattered aspen groves), along with planted upland grass (extensive old fields/CRP) and some agricultural lands. This IBA provides important habitat for sedge/wet prairie obligate birds, particularly Yellow Rail, Wilson?s Phalarope, and Nelson?s Sparrow. Other wetland and grassland species present on the IBA include American Bittern, Upland Sandpiper, Marbled Godwit, Greater Prairie-Chicken, Sharp-tailed Grouse, Sandhill Crane.
The Goose Lake Swamp IBA lies within the Aspen Parkland region, approximately 300 miles northwest of the Twin Cities. The IBA is located along the border between Pennington and Polk counties, with a small portion in Red Lake County. The historic Pembina Trail, an old oxcart route, runs through the IBA. The largest cities nearby are Thief River Falls, approximately 12 miles to the east, and Red Lake Falls, roughly 11 miles to the southeast. Several small towns near the IBA include St. Hilaire to the east, Euclid and Angus to the west, and Dorothy to the south.
The Aspen Parkland region, extending from northwestern Minnesota through the Canadian Prairie Provinces, is a unique transition zone between the prairie and coniferous forest biomes. Most of the IBA lies on the lakebed of Glacial Lake Agassiz, which covered northwestern Minnesota, eastern North Dakota, and large portions of Ontario and Manitoba at the end of the last Wisconsin glacial period. The topography of this IBA is level to gently rolling, with the only relief provided by ancient beach ridges rising above the otherwise flat terrain.
Historically, fire played an important role in maintaining the open character of the vegetation in this landscape. The dominant trees in the region are quaking aspen and bur oak, typically rather small in stature, occurring in groves interspersed with prairies and wetlands. Fire suppression has allowed many of these areas to develop into dense forests of larger trees. Much of the native prairie is categorized as ?brush prairie? due to a significant short shrub component. Dry prairie, wet prairie, and sedge habitats are also important in this region.
Pembina Wildlife Management Area (WMA), owned and managed by the Minnesota Department of Natural Resources (DNR) Section of Wildlife, comprises 30% (6,239 acres) of the IBA. Approximately 1,508 acres are owned by the DNR Division of Forestry in the north unit. Current (2007) Conservation Reserve Program (CRP) enrollment amounts to 8,400 acres, and 139 acres of land are under Reinvest in Minnesota (RIM) easements.
Outside of public lands, most of the grasslands within the IBA are in CRP or RIM. The semi-natural state of these intervening areas provide important connections between many of the large blocks of aspen parkland vegetation, and provided important habitat for open country bird species.
Goose Lake Swamp IBA lies within the Aspen Parkland Physiographic Area which harbors the highest number of breeding species of any physiographic area on the continent. The IBA is of particular importance because it encompasses an extensive, linear wetland of sedges, marsh, and native prairie, in an otherwise intensively-cultivated area. Like other IBAs in the Aspen Parkland Region, Goose Lake Swamp is relatively far from major urban centers and therefore is infrequently visited by most birders. Surveys for breeding birds, particularly nongame species, have been very limited and most information on numbers of birds is based on surveys by the Minnesota Department of Natural Resources- Minnesota County Biological Survey conducted between 1992 - 1995. The maximum numbers listed represent the number of survey locations (point counts, species lists, or incidental records) at which a species was detected. However, many areas were not surveyed, so actual numbers of breeding pairs are undoubtedly higher than indicated.
During the breeding season this area supports a substantial number state-listed species (% of state records in parenthesis), including Yellow Rails (4%) Wilson's Phalaropes (3%), Nelson's Sparrows (5%) Greater Prairie-chickens, and Marbled Godwits. Goose Lake Swamp is the 5th-ranked area statewide for numbers of Yellow Rails and Nelson's Sparrow.
Ten non-listed species of concern have been documented on the IBA, five of which are frequent. At least four species probably meet the threshold required to meet this criteria: Sharp-tailed Grouse (5+ dancing grounds), American Bittern (12+ records), Le Conte's Sparrow (12+ records), Bobolink (33+ records). Note that the numbers listed represent the number of individuals documented during surveys of a relatively small portion of the IBA, so actual populations are probably significantly higher because of the amount of suitable habitat present that has not been surveyed for birds. Several other species of conservation concern probably occur in the IBA in significant densities, particularly American Woodcock and Black-billed Cuckoo. The woodcock is largely nocturnal/ crepuscular, and is not well-documented by MCBS survey methodology.
Historically, frequent fire was an important natural process essential in maintaining the open character of the aspen parkland landscape that dominates much of this IBA. In the absence of fire, open grassland and sedge habitats often become overgrown with undesirable levels of woody vegetation. Minnesota DNR Wildlife Management Areas are typically managed through prescribed burning in an effort to maintain and/or enhance the open character of the aspen parkland landscape. This is an ongoing effort, often contingent on available funds for management activities.
Ditching in the Aspen Parkland Region has already resulted in the drainage of vast areas, which in turn has allowed cultivation of areas that otherwise would be unsuitable for agriculture. Goose Lake Swamp?s shallow wetlands, particularly sedge wetlands and wet prairie, and species dependent on these habitats (e.g., Yellow Rail, Wilson?s Phalarope, and Nelson?s Sparrow), are very sensitive to even small drops in water levels. Continued or increased drainage would further impact or destroy shallow wetland and wet prairie habitats. Flood control projects, or other impoundments, if proposed, could negatively impact or eliminate sensitive wetland habitats.
Changes to the amount of agricultural land enrolled in the Conservation Reserve Program (CRP), or other set-aside programs, could greatly influence the amount of grassland habitat in this IBA. Gravel pits are currently somewhat limited in this area, but continue to be a threat ? particularly on beach ridges. Expansion of gravel mining would certainly have detrimental effects on native birds and their habitats in the IBA.