136 NORTH AMERICAN FAUNA 73 



Habitat: Most observations of orange-crowned warblers have been in decid- 

 uous woods of various early successional stages. Occasional individuals 

 have been observed foraging at the edge of cattail marshes, primarily during 

 spring migration. 



Nashville Warbler [Vermivora ruficapilla) 

 Status: Regular migrant and nesting species. 



Migration: Common migrant throughout the Valley, locally abundant in 

 coniferous habitats of the Northern Highland. Spring migrants begin to 

 arrive in the Western Upland about 1 May. reaching the Northern Highland 

 10-15 May. Peak spring migration occurs 10-20 May and departure of non- 

 breeders by 30 May. FaU migration begins with family dispersal in early 

 August; however, the first obvious migratory movements occur after 

 10 August. The first fall migrants reach the Western Upland about 

 20 August (earUest — 14 August 1963. St. Croix County). Peak fall migration 

 occurs 1-15 September and departure by 5 October (latest— 19 October 

 1968, Pine County). 



Nesting Season Distribution: Common breeding bird throughout the North- 

 ern Highland; less common and more locahzed in the Central Plain. No 

 breeding records exist for the Western Upland. Jackson (1943) referred to 

 the Nashville Warbler as "one of the most plentiful Warblers in summer in 

 most of the region" in 1919. Breeding Bird Survey data (Table 6) demon- 

 strate the rapid increase in relative abundance moving northward from the 

 Central Plain. 



Habitat: Breeding Nashville warblers have been recorded in a variety of 

 deciduous and coniferous habitats. Greatest use appears to be in coniferous 

 habitats and of these Black Spruce-Tamarack Bogs are probably the most 

 important. 



Northern Parula [Parula americana) 

 Status: Regular migrant and summer resident. 



Migration: Rare and local migrant in the Western Upland and Central Plain, 

 uncommon in the Northern Highland. Spring migrants arrive 5-10 May in 

 the Western Upland, reaching the Northern Highland 10-15 May. Because 

 of the low^ numbers recorded, no peak dates have been determined. De- 

 parture from the southern regions occurs by 20 May. Fall migration is 

 diffuse as very few birds were recorded each year. Available data suggest 

 that the main period of migration extends from 20 August to 20 September. 



Nesting Season Distribution: Rare and local summer resident of the North- 

 ern Highland. Available records suggest the main part of their breeding 

 range hes north of the St. Croix River in Douglas and Pine counties. The 

 only Breeding Bird Survey route in the Valley that has recorded this species 

 is the Minong route in Douglas County. 



Habitat: Although confirmed nest records are lacking, this species un- 



