Stream flow vol\imes estimated with Robins and Crawford method (1954) 



LIMITING FACTORS 



Speculation on natural limiting factors affecting potential harleguin 

 duck reproduction on the Kootenai NF could include: stream flow 

 volumes (1989 spring runoff was more "normal" than previous drought 

 years); adequate stream habitat components; gradient levels; aquatic 

 insect populations; eind direct/indirect competition for brood 

 rearing habitat with the common merganser. Other factors which may 

 influence harlequin production would include: private landowner 

 activities; fishing pressure (i.e. Graves Creek); timber hai-vest / 

 road building affecting riparian zone and water quality; and 

 potential hard rock mining activities. 



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