HABITAT 



Nesting North American White-winged Scoters breed along inland lakes and 

 streams, on islands and islets in inland waters, and inland in treeless or fair- 

 ly open country (Palmer 1976b). Nests are commonly found near water (Palmer 

 1976b) but are sometimes found as much as a half-mile (a quarter kilometer) 

 away, where they are usually situated in dense cover (authors cited _in Bellrose 

 1976). In a recent study conducted in Saskatchewan and Alberta, Brown and Brown 

 (1981) found that most nests were in dense cover at least 50 m (160 ft) from 

 the nearest shoreline. Redshoot gooseberry ( Ribes setosum ) was the primary 

 cover for almost all the nests found at Redberry Lake, Saskatchewan. At Jessie 

 Lake, Alberta, gooseberry, western snowberry ( Syraphoricarpos occidentalis ) , 

 roses ( Rosa spp.), and raspberry ( Rubus spp.) were all important cover plants. 



Cramp et al. (1977) reported that White-winged Scoters in the Old World 

 generally breed nearer fresh or brackish waters than does the Black Scoter. 

 Nests are well concealed and usually within 100 m (330 ft) of water, although 

 some may be found 2-3 km (1.2-1.9 mi) away. 



Feeding Palmer (1976b) indicated that roosting and foraging birds prefer 

 sheltered waters in shallow bays and to the lee of islands. Cramp et al. (1977) 

 added that Velvet Scoters (= White-winged Scoters) were more likely to feed in 

 broken water among rocks and islands than Black Scoters. 



White-winged Scoters usually forage in waters less than 25 ft (7.6 m) deep 

 but dives of as much as 60 ft (18 m) have been reported (Johnsgard 1975). 

 Cramp et al . (1977) stated that the normal foraging depth was ca. 5 m (16 ft). 



Winter and Offshore Wintering and non-breeding White-winged Scoters are 

 usually found in brackish and marine coastal waters; in these areas, they prefer 

 shallow water over shellfish beds that have sandy or gravelly bottoms (Palmer 

 1976b). Johnsgard (1975) described this habitat as the "littoral zone of the 

 ocean, just beyond the breakers and within a mile of shore." Habitats reported 

 for wintering birds in the Old World are similar (Cramp et al . 1977). 



White-winged Scoters tend to form flocks of about 10-15 birds when large 

 numbers are present on saltwater bays (Palmer 1976b). Cramp et al . (1977) 

 pointed out that this species usually occurs in smaller flocks than does the 

 Black Scoter. 



FOOD AND FEEDING BEHAVIOR 



White-winged Scoters feed by diving from the surface. They use their feet 

 for propulsion and dive with partially opened wings (Palmer 1976b, Cramp et al. 

 1977). They make repeated short dives, with about twice as much time spent 

 underwater as at the surface (Palmer 1976b), and they may exhibit synchronized 

 diving (Cramp et al. 1977). In summarizing reports from various areas, Cramp 

 et al. (1977) reported that these ducks usually submerged for 20-40 sec in 

 southwest Finland, and they cited extremely long dives of 56 and 65 sec. 



Aside from diving for food, White-winged Scoters also occasionally dabble 



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