4 April 1970 on the Middle Fork Flathead River (Kuchel 1977:32). Pairs begin to arrive in late 

 April and most are present by early May (Kuchel 1977, Ashley 1994). Two-year-old females may 

 arrive later than older females (Ashley 1994; Kuchel 1977:32). Males begin leaving Montana by 

 late-May, and are typically gone by late June (Kuchel 1977, Reichel and Center 1993, Ashley 

 1994). Females may leave by early July if breeding is unsuccessful, and by mid-late July if 

 successful; they often leave prior to their young fledging (Reichel and Center 1996). Young birds 

 leave last, beginning in early August, and nearly all birds are gone by the beginning of September 

 (Ashley 1994). 



In Washington, birds amve on breeding streams m late March or early April (Schirato 1993). 

 In Oregon, birds arrive on the breeding streams in late April, although some have been reported as 

 early as late February (Latta 1993). 



Of 249 Harlequins banded in Montana from 1991-1995, a minimum of 24 have been reported 

 from Oregon (2), Washington (1), and southern British Columbia (21) including Vancouver Island 

 and Hornby Island (Ashley 1995, Reichel and Center 1996). Sexes and ages at banding show the 

 following numbers and percentages observed: adult female (6, 1 1%), aduh males (2, 5%), juvenile 

 females (9, 7%), and juvenile males (7, 5%) (Ashley 1995, Reichel and Center 1996). Two 

 females radio-marked in Idaho were located in the San Juan and Culf Islands of Washington and 

 British Columbia, while one banded bird was reported from northwestern Washington (Cassirer 

 and Croves 1994) 



There are few records of birds between their breeding areas and wintering areas. A single 

 marked bird has been observed en route between the breeding and wintering grounds (Cassirer 

 and Croves 1991, Wallen 1993). She was originally marked in Wyoming and observed on the 

 way back to the breeding stream on Crooked Creek, South Fork Clearwater drainage, in central 

 Idaho (Cassirer and Croves 1991). She was seen about a week later in Crand Teton National 

 Park and had nested successfully. The only known wintering bird marked m Wyoming was 

 observed off San Juan Island in Washington m August 1989; he returned to Crand Teton National 

 Park as an unpaired male in 1990 (Cassirer and Croves 1991, Wallen 1993). 



Migratory behavior It is believed that nearly all one-year-old birds, and some (perhaps most) 

 two-year-old birds remain in coastal water, not moving to breeding streams until they are 2-4 

 years of age. 



HABITAT PARAMETERS 



BREEDINC RANCH TERRESTRIAL 



Throughout their range. Harlequin Ducks use a wide variety of habitat types during the breeding 

 season. Typically they are found on swift, clear streams in a variety of habitats ranging from old 

 growth to second growth to arctic tundra (Philips 1925, Salomonsen 1950, Bengtson 1966, 

 Dement'ev and Caldkov 1967, Inglis et al. 1989, Cassirer and Croves 1991, Diamond and 

 Finnegan 1993, Cassirer and Croves 1994, Ashley 1994). They also apparently breed in coastal 

 estuaries of British Columbia (Breault 1993), Alaska, and Russia (Portenko 1981). though this 

 phenomenon is poorly studied or understood. 



Overstory In Idaho, Harlequins were strongly associated with mature to old-growth western 

 red cedar/western hemlock {Thuja plicatalTsiiga heterophylla) forest (Cassirer and Croves 



