Forest adds to current information of harlequin duck habitat and 

 breeding biology in Montana. 



First observations of harlequin ducks were on 6 May 1990, 

 the first day of surveys. Kuchel (1977) found harlequins on 

 McDonald Creek in nearby Glacier National Park in late April and 

 Wallen & Groves (1989) determined that most harlequins arrived in 

 Idaho by the first week of May. They speculated that harlequins 

 may arrive in late April in Idaho and remain unnoticed due to the 

 isolated nature of the habitat. My observation should not be 

 construed as an arrival date. 



Breeding Biology 



Estimated hatching dates of broods observed, (table 3) , are 

 consistent with the range of hatching dates for harlequins in 

 Glacier National Park (Kuchel 1977) . These dates are later than 

 the average hatching date of 6 June found in Idaho (Wallen & 

 Groves 1989) . 



DATE LOCATION BROOD AGE HATCHING DATE 

 ; SIZE CLASSIFICATION (+/• 3 davs\ 



7/30/90 Sullivan Creek 4 lla 7/12/90 



8/7/90 Trail Creek 4 Fledged 6/26/90 



8/7/90 Trail Creek 2 III 6/29/90 



7/12/90 Middle Fork Flathead River 4 ? ? 



Table 3. Location, age, and classification of harlequin duck 

 broods observed on the Flathead National Forest, 1990. 



The average size of broods was 3.5 (n=4) with a range of 2 

 to 4. This is the same average brood size Wallen & Groves (1989) 



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