to leave slightly earlier than the paired drakes. Unpaired 

 females remain at nesting grounds for 3-5 weeks before 

 returning to the coastal waters. Hens with broods remain for 

 approximately 4 months, departing with or slightly before their 

 broods (Kuchel 1977, Wallen 1987, Wallen and Groves 1989, Miller 

 1988 and 1989) . 



Breeding Biology 



Harlequin females begin breeding when 2 years old (Bellrose 

 1980) . Brood size varies from 1-9 individuals with the most 

 successful broods occurring in areas with low human disturbance 

 (Kuchel 1977, Wallen 1987, Wallen and Groves 1989, S. Diamond 

 pers.comm. 1990) . Harlequins exhibit a strong nest site 

 tenacity, often returning to their same nesting area yearly 

 (Bengston 1966, Wallen 1987, Kuchel 1977, Dzinbal 1982, Wallen 

 and Groves 1989) . Additionally, the offspring exhibit natal 

 fidelity, often returning to the areas where they were hatched 

 and raised (Kuchel 1977, Wallen 1987). 



Wallen and Groves (1989) estimated incubation of eggs in 

 Idaho to begin mid-May and hatching to occur 30 days after. 

 Miller (1989) observed similar findings in western Montana. 

 Incubation and hatching dates of broods in Grand Teton National 

 Park were observed to occur 1 month later than that of the Idaho 

 population; with nesting times initiating in mid-June and 

 hatching in mid-July (Wallen 1987, Wallen and Groves 1989). It 

 appears that both the nesting and hatching times and the arrival 



