Reproduction 



Harlequins were present this year on at least 12 streams in the 

 study area and adult females or broods were seen on 11 of those 

 streams. A minimum of 42 adult females were present. Of 42 

 potential broods, a minimum of 31 were produced for a 74% success 

 rate of broods per adult female. Mid-late August brood size 

 averaged 3.27 (n=30) . Most broods were seen in Class III or 

 fledged stages of development (Bellrose 1976:27), and we made no 

 adjustment for age of broods in our calculation of mean brood 

 size. Success rates per adult female are biased by having 

 incomplete early pair surveys for comparison on some streams, 

 resulting in high recorded success rates. However, this may have 

 been offset by some broods fledging and leaving the area prior to 

 brood survey completion on some streams such as Trail Creek and 

 the Vermillion River. 

 ^Capture and Marking 



The first year of the juvenile Harlequin Duck site fidelity and 

 survival study got off to a good start. A total of 62 juvenile 

 birds from 4 drainages were captured and marked (Table 3, 

 Appendix D & E) . Five adult males and 18 adult females were 

 marked in addition to the 4 males and 2 females marked in 1991 

 (Table 3, Appendix D & E) . 



The two females and one male marked with nasal disks on 

 Marten Creek in 1991 were recaptured in 1992. No problems with • 

 the nasal disks were apparent. The ducks appeared healthy and 

 each female successfully raised broods of 4 young during 1992. 



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