1 male 



May 22 



1 female 



May 22 



8 slightly incu- 



June 23 



bated eggs 





OLD CROW 173 



Aythya ajffinis (Eyton) 



weight 640 g. medium fat testes 8x21, 9x18 mm. 

 weight 613 g. little fat 



On May 18 the male of a pair of scaup near the village was identified 

 as A. affinis by its purple head, but some seen a few days earlier were 

 thought also to be lesser scaup. Occasionally scaup alighted in 

 pools with mingled species of ducks, but they did not join with other 

 species in organized flights. In the few days just before breakup 

 occasional small flocks and many individuals and pairs of scaup 

 were seen. Only a few individuals could be positively identified as 

 lesser scaup and the directional trend of their flights was not deter- 

 mined. By the time of breakup several pairs of lesser scaup had been 

 identified by sight among the considerable number of pairs seen in 

 the partially open water of small lakes. The two specimens were 

 flying together when they were obtained for us by Father Mouchet. 

 The testes of the male specimen were only the size of a teal's and 

 were probably immature. 



Scaup were seen paired about as early as were mallards and teal, 

 but the pairs of scaup remained longer evident as they swam on the 

 lakes, while pairs of mallards and teal did not long appear together. 

 On June 13 the last demonstration of pairing appeared when a male 

 lesser scaup rushed away from a female to attack a surf scoter which 

 had been shot nearby. On June 15 there were about ten male lesser 

 scaup scattered about on a lake with no females in view and the males 

 flew about singly as if not attached to a particular locality. The re- 

 formation of flocks of male scaup was not noticed during June. 



On June 28, 1957, Irwin Linklater found eggs in a nest on top of 

 a moss and willow hummock 50 feet from the shore of a small lake. 

 Estimating about three days of incubation, the first egg was laid on 

 June 18. 



As evidence for late nesting of scaups, of a group of 4 flightless 

 young scaup 2 which were shot on September 2, 1958 had only pin- 

 feather primaries and were about half the adult weight. 



Although Rand (1946) had found reports on lesser scaup only 

 from southern Yukon it is evident that the Mackenzie and Alaskan 

 birds are connected by continuous nesting across Yukon as far north 

 as Porcupine. 



The Indian name is Nityitin. 



