from one locale to another, differences in elevation, or for other 

 reasons unknown at this time (Kuchel 1977; Wallen 1987). Egg 

 incubation in Idaho begins in mid-May with hatching occurring 30 days 

 after (Wallen and Groves 1989). 



Wallen and Groves (1989) found harlequins in Idaho to occupy fast 

 running mountain streams with a dense canopy of shrubs. Aquatic 

 insects are the primary diet of harlequins in the Rocky Mountains 

 (Kuchel 1977; Wallen 1987). A number of studies documenting 

 harlequin habitat in the Rocky Mountains have taken place over the 

 past 15 years (Kuchel 1977; Wallen 1987; Wallen and Groves 1989; 

 and Fairman and Miller 1990). Based on these studies it is possible to 

 develop a list of summer habitat requirements for harlequins: 



1. a stream with good water quality and a high density of 

 aquatic insects. 



2. a low gradient perennial stream with areas of swift water. 



3. stream side cover, usually comprised of moderate to dense 

 shrubs. 



4. presence of cover and loafing areas such as logjams, debris 

 piles, mid-stream rocks, and gravel bars. 



5. presence of brood rearing areas such as beaver ponds, stream 

 braids, meanders, side channels. 



These habitat requirements may assist public land managers with 

 policies accommodating the needs of harlequin ducks. 



