CONSERVATION STRATEGY 



Introduction 



The intent of this Conservation Strategy is to prevent declines in current population levels of 

 the harlequin duck ( Histrionicus histrionicus - ) in the Rocky Mountain breeding range of Idaho, 

 Montana, and Wyoming. The primary goal is to maintain viable populations along with protection and 

 maintenance of critical habitats to ensure that listing is not warranted, in accordance with the 

 Endangered Species Act (ESA) of 1973 as amended. Establishment of management guidelines is 

 complicated by a limited knowledge base and by the fact that harlequin ducks exhibit significant 

 variation in some aspects of breeding ecology and behavior throughout their range. A monitoring 

 program should be developed for all occupied areas affected by proposed management activities and 

 this strategy should be updated as necessary to reflect current knowledge. 



This Conservation Strategy focuses on the harlequin duck, but will also benefit other riparian 

 and aquatic-dependent species, including Federal and State special status species such as bull trout 

 ( Salvelinus confluentus ) and westslope cutthroat ( Oncorhyncus clarki lewisi ). Likewise, management 

 for these fish species will benefit harlequin ducks. 



Standards and guidelines 



Standards and guidelines apply to habitat along occupied harlequin duck breeding streams, 

 including breeding streams, probable breeding streams, and streams of unknown breeding status 

 (Appendix A,B,C, Tables 1 and 2 ). Management guidelines are intended to protect habitat 

 components (security, cover, food), necessary for harlequin ducks to complete their life cycle. The 

 following standards and guidelines should be followed unless cumulative effects watershed analysis and 

 site specific analyses by a qualified biologist addressing harlequin duck habitat parameters indicate that 

 habitat function can be maintained using alternative methods. 



Timber management 



Timber management guidelines are specifically intended to: avoid disturbance of breeding birds, (TM- 

 1) and maintain security cover and nesting habitat (TM-2, TM-3). The goal of timber management 

 guideline TM-4 is to avoid increasing spring and summer stream flows which can reduce harlequin 

 duck productivity by washing away nests and/or ducklings. Finally, guidelines TM-3 and TM-5 are 

 intended to prevent increases in sedimentation which could impact the harlequin duck's food supply 

 (aquatic insects) and foraging ability. 



TM-1. Active logging and road construction activities (such as harvest, skidding, grading, blasting, 

 excavation, etc.) within 2 sight distances' of riparian zones should be conducted outside the 



1 Sight distance is a measure of hiding cover often defined as the distance at which 90% or 

 more of an adult animal is hidden from view (Thomas et al. 1976, Lyon and Christenson 1992). In 

 this conservation strategy sight distance is defined as the distance at which the green line 

 vegetation or riparian area is obscured from view prior to leafout. Two sight distances is double 

 this distance. 



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