south (Bellrose 1976). For further details on the migration of Lesser Scaup see 

 Bellrose (1976) and Palmer (1976b); their interpretation of migratory routes may 

 vary in detail. 



HABITAT 



Nesting Lesser Scaup nest near ponds, lakes, potholes, sloughs, marshes, 

 in river deltas, on seasonally flooded flats, and on islands (Bellrose 1976, 

 Palmer 1976b). They often nest semi-colonially, with the largest nesting con- 

 centrations in hardstem bulrush ( Scirpus acutus ) marshes along lakes with an 

 abundant food supply (Palmer 1976b). This species preferred to nest in sedges 

 in Lousana, Alberta, and in the Saskatchewan Delta; in the latter area most of 

 the nests were on floating or semi-floating plants. In another part of Alberta 

 juncus beds were preferred over mixed prairie (authors cited Jji Bellrose 1976). 

 Studies cited by Bellrose (1976) indicate considerable variation in the proxim- 

 ity of the nest to water. Average distances listed in one pothole area with 

 strongly fluctuating water levels ranged from 7 to 125 ft (2.1 to 38.1 m) over 

 a period of four breeding seasons. 



Feeding Lesser Scaup feed in a wide variety of habitats, often in immense 

 rafts. Bellrose (1976) saw thera foraging in roadside and farm ponds and on 

 flooded fields only a few feet deep, as well as in water 10-40 ft (3- 12 m) 

 deep that were 5-10 mi (8-16 km) offshore in the Gulf of Mexico. He stated 

 that this species feeds more commonly in water 10-25 ft (3-8 m) deep. Palmer 

 (1976b) indicated that Lesser Scaup preferred to feed in water 1-3 m (3-10 ft) 

 deep. 



Winter and Offshore Winter habitat of the Lesser Scaup consists of bays 

 and estuarine waters, flooded coastal marshes, and open fresh water both inland 

 and along the coast (Palmer 1976b). This scaup prefers more sheltered waters 

 than the Greater Scaup (Bellrose 1976), but compact flocks of dozens to thou- 

 sands of resting birds may be found well offshore (Palmer 1976b). Bellrose 

 (1976) remarked that Lesser Scaup feed in deeper water than other diving ducks 

 (except for the sea ducks, e.g., Oldsquaw) . 



FOOD AND FEEDING BEHAVIOR 



Lesser Scaup feed principally by diving from the surface using the feet 

 for propulsion; they will also "tip-up" in shallower water (Palmer 1976b). They 

 tended to dive obliquely on ponds in Manitoba (Siegfried 1976b). Palmer (1976b) 

 described diving behavior in more detail. 



Palmer (1976b) suggested that Lesser Scaup in tidewater areas vary their 

 times of feeding with the tide and remarked that they feed nearer shore at high 

 tide. Males and females dove for mean periods of 10.3 and 13.2 sec, respective- 

 ly, while foraging on ponds in Manitoba (Siegfried 1976b). On coastal impound- 

 ments in South Carolina, diving times varied from 6.3 sec in water 1.5 m (4.9 ft) 

 deep to 16.6 sec in water 0.5 m (1.6 ft) deep (Alexander and Hair 1979). At 

 these coastal impoundments Lesser Scaup fed by themselves or in loosely associ- 

 ated pairs. They fed at a mean rate of 5.1 dives per second; Alexander and 



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