LIFE SPAN AND SURVIVORSHIP 18 



CAUSES OF MORTALITY 19 



Causes of death 19 



Exposure and predation 20 



RANGE 20 



Dispersal from natal stream 20 



Fidelity to natal stream 20 



Adult fidelity to breeding stream 20 



POPULATION STATUS 20 



Estimates or counts of density 20 



Numbers 21 



Trends 22 



POPULATION REGULATION 23 



CONSERVATION AND MANAGEMENT 23 



EFFECTS OF HUMAN ACTIVITY ON HARLEQUIN DUCK POPULATIONS, 



REPRODUCTION, AND BEHAVIOR 23 



Disturbance on the breeding grounds 23 



Noise 25 



Collecting and trapping 25 



Shooting 25 



Fishing 25 



Pesticides and other contaminants/toxics 25 



Degradation of habitat: breeding and wintering 26 



MANAGEMENT 26 



Federal 26 



States/Heritage Programs 26 



Other legal status 26 



Mitigation procedures 26 



PRIORITIES FOR FUTURE RESEARCH 27 



REFERENCES 29 



Appendices 41 



Appendix A. Data Forms 42 



Appendix B. Harlequin Streams in Montana: Actual, Possible, and Potential 48 



Appendix C. Montana Harlequin Duck surveys: 1995 56 



Appendix D. List of Harlequin Ducks observed on surveys in 1995 60 



Appendix E. Miscellaneous reports of Harlequin Ducks during 1995 64 



Appendix F. Harlequin Duck numbers in each occurrence for Montana 68 



Appendix G. Streams surx'eyed for Harlequin Ducks in Montana during 1987-94 71 



VI 



