BIRDS OF THE ST. CROIX RIVER VALLEY 



39 



This release met with limited success because the first brood was not ob- 

 served until 1974. In the prairie wetlands of southern Polk and central St. 

 Croix counties, gadwalls occur as a rare nesting species in a narrow band be- 

 tween Roberts (St. Croix County) and Alden Township (Polk County), 



Winter: One bird was recorded on the Afton CBC in St. Croix County on 

 1 January 1973. 



Habitat: Nesting gadwalls at Crex Meadows are generally associated with 

 man-made potholes constructed to resemble natural basin wetlands. In St. 

 Croix and southern Polk counties, breeding pairs are typically associated 

 with seasonally and semipermanently flooded wetlands. Vegetation of these 

 wetlands is composed of cattail, bulrushes, and various other emergent 

 species. 



Pintail (Anas acuta) 



Status: Regular migrant and nesting species, one winter record. 



Migration: Fairly common spring migrant in the Western Upland and 

 Central Plain, uncommon and local in the Northern Highland. Pintails are 

 among the first dabbling ducks to arrive in the region, usually 5-15 March. 

 Peak spring populations occur 10-20 April, and depart by 15 May. Goddard 

 (1975) found that pintails made up 0.9% of the spring migrant waterfowl in 

 St. Croix County and 2.8% of the migrant dabbling duck population. 



Fall migrants arrive in late August. During the fall, pintails are fairly com- 

 mon at Crex Meadows, Burnett County, in central St. Croix, and eastern 

 Washington counties, and in southern Polk County. They are rare and local 

 in other regions during this period. Peak fall populations occur 25 Septem- 

 ber to 10 October and departure occurs by 15 November. Largest fall popu- 

 lations at Crex Meadows have been 400 birds reported on 4 October 1956, 

 29 September 1964, and 27 September 1973. 



Nesting Season Distribution: Uncommon and local nesting species with rec- 

 ords from Washington (Green and Janssen 1975), St. Croix, Polk, and Bur- 

 nett counties. In central St. Croix and southern Polk counties, pintails made 

 up 0.8% of the breeding duck population (Peterson 1978). At Crex Meadows, 

 waterfowl pair counts indicated that pintails constituted about 1% of the 

 yearly breeding population from 1957-78 (WDNR files). 



Winter: One pintail was observed on the St. Croix River, Burnett County, on 

 12 and 13 January 1949 (Robbins 1949). Afton CBC data include single pin- 

 tails on 1 January 1972 and 1973, and two birds on 1 January 1974, 1976, 

 and 1978. 



Habitat: Nesting pintails are typically associated with seasonally and semi- 

 permanently flooded wetlands that support a lush growth of emergent 

 aquatic vegetation. 



Green- winged Teal {Anas crecca) 



Status: Regular migrant and nesting species, two winter records. 



