BIRDS OF THE ST. CROIX RIVER VALLEY 



65 



populations are reduced because of farming practices that eliminated most 

 of their habitat. Urban expansion has not impacted this species to nearly the 

 extent that agricultural production has. Green and Janssen (1975) stated 

 that the largest populations remaining in Minnesota exist in the Twin Cities 

 metropolitan area. 



Habitat: The ring-necked pheasant is a species of agricultural areas, pri- 

 marily edge habitats including field margins, fencerows, retired cropland. 

 Old Field Communities, and heavily vegetated wetlands. Ring-necked pheas- 

 ants in the Central Plain have shown an encouraging response to Managed 

 Grasslands that are maintained for duck production. 



Gray Partridge {Perdix perdix) 

 Status: Introduced permanent resident. 



Distribution: Rare resident of the Western Upland. The small population 

 that exists in the Valley is largely restricted to a small area of central St. 

 Croix County. The largest population occurs near the village of Roberts in T. 

 29 N., R. 18 W.; T. 29 N., R. 17 W.; and T. 30 N., R. 17 W. Distribution of 

 the population in the Minnesota counties is poorly known, although Mettler 

 (1977) showed that the species range included southern Washington County. 

 McCabe and Hawkins (1946) reported a population density of 0.6 coveys per 

 62 km in St. Croix County. 



Habitat: The gray partridge is primarily a species of croplands and adjoin- 

 ing edge habitat. Preferred habitats include corn and oats fields, weedy 

 edges of summer fallow, and remnant patches of native prairie along railroad 

 rights-of-way that border agricultural fields. 



FAMILY GRUIDAE: Cranes 



Sandhill Crane {Grus canadensis) 

 Status: Regular migrant and nesting species. 



Migration: Rare migrant throughout the Valley, locally common at Crex 

 Meadows, Burnett County. Sandhill cranes have been observed in Wash- 

 ington County on four occasions: 31 March 1967, 9 April 1970 and 1971, and 

 20 November 1970. Three records exist for St. Croix County: 17 April 1947, 

 4 May 1974, and 30 October 1977. There is one record (29 April 1950) for 

 Polk County. 



The most reliable data on migration is from Crex Meadows, where the 

 average date of spring arrival is 4 April (earUest— 25 March 1976). Peak 

 spring concentration occurs about 20 April. During fall migration, the first 

 migrants arrive in early September and peak abundance is 15 October to 

 1 November. During this period, concentrations of 150 to 200 individuals 

 commonly occur on the refuge portion of Crex Meadows; high counts were 

 350 on 19 October 1975 and 420 on 30 October 1977. Departure of fall mi- 

 grants occurs soon after freeze-up; the latest was on 18 November 1962. 



