BIRDS OF THE ST. CROIX RIVER VALLEY 



15 



with the Wisconsin glacial epoch, which ended about 10,000 years ago. 

 Upland soils associated with these wetlands are highly fertile loams and silt 

 loams which are very important for agricultural production. Related to this, 

 large hectarages of Prairie Wetlands have been drained or seriously altered 

 to facilitate expanding agricultural production. 



Principal emergent and submerged aquatic vegetation associated with 

 these freshwater, low-acidity wetlands include hardstem bulrush, softstem 

 bulrush, river bulrush, cattail, cane reed, spikerush, burreed, coontail, and 

 water milfoil. Other important species dependent on water permanence and 

 the degree of acidity include arrowhead, water plantain, and reed canary 

 grass. 



Characteristic breeding birds associated with Prairie Wetlands include 

 pied-billed grebe*, American bittern*, Canada goose*, mallard*, gadwall*, 

 pintail*, green-winged teal*, blue-winged teal*, ruddy duck*, Virginia rail*, 

 sora*, American coot*, black tern*, tree swallow*, long-billed marsh wren*, 

 yellow warbler, common yellowthroat, yellow-headed blackbird*, red-winged 

 blackbird*, swamp sparrow, and song sparrow. 



Forest Bordered Wetlands 



Although similar to Prairie Wetlands in geologic origin. Forest Bordered 

 Wetlands are different in flora and fauna. This community is widespread 

 throughout the area north of the Tension Zone. Forest Bordered Wetlands 

 are usually similar in size, but much deeper than Prairie Wetlands, and the 

 interspersion of emergent and submerged aquatic vegetation is less pro- 

 nounced. Acidity of the water in Forest Bordered Wetlands is generally 

 greater than in Prairie Wetlands. Principal emergent and submerged 

 aquatic vegetation associated with this community includes cattail, wild 

 rice, iris, pickerelweed, arrowhead, water plantain, bladderwort, elodea, 

 coontail, water milfoil, white waterlily, and yellow waterlily. 



Characteristic breeding birds associated with these wetlands include com- 

 mon loon*, green heron, mallard, black duck*, wood duck, ring-necked 

 duck*, hooded merganser, Virginia rail, belted kingfisher, tree swallow, 

 long-billed marsh wren, yellow warbler, common yellowthroat, red-winged 

 blackbird, brown-headed cowbird, swamp sparrow, and song sparrow. 



Riparian Habitats 



The streams and rivers of the Valley are well known for their recreational 

 attractions. Among the important rivers are the Snake, Kettle, Willow, 

 Apple, Clam, Namekagon, and Kinnickinnic. Numerous small streams that 

 are tributaries of these larger rivers often provide excellent trout fishing. 

 Breeding birds associated with streams and rivers may also be included in 

 larger deciduous and coniferous communities. However, nesting strategies 

 of several species are closely related to certain aspects of the ecology of mov- 

 ing water. Principal among these breeding birds are the great blue heron* 

 (locally), mallard, wood duck*, hooded merganser*, spotted sandpiper*, 

 belted kingfisher*, eastern phoebe*, rough-winged swallow*, cliff swallow*, 

 American robin, yellow warbler, common yellowthroat, red-winged black- 

 bird, and song sparrow. 



