Montana. 



4) What are the critical habitat components hmiting Harlequin Duck breeding and wintering 

 populations? 



Harlequin Ducks use a wide variety of habitats on the breeding grounds, from forests to tundra. 

 Habitat usage should be documented over a large number of study areas to identify common 

 habitat components and compare them to available habitat; there are both large and small scale 

 considerations here. See Proposals 2, 3, 4. 



5) How and why do productivity and survival change over time and among areas, and what are 

 the relative impacts of these changes on populations? 



Long term studies are needed to determine population parameters and then incorporate them into 

 population models (with information from movements on the breeding and wintering grounds). 

 These parameters include; productivity; age-related survival; recruitment; age(s) at first breeding 

 and/or successful breeding; age(s) last breeding; life expectancy; and causes and timing of 

 mortality. These can only be done with long-term studies involving marked birds on both the 

 breeding and wintering area. Currently we are in a good position to complete these studies given 

 that we already have 4 years of data and coastal populations are currently being marked and 

 studies. See Proposal 1 . 



The most difficult question is the causes of mortality, which is not tractable given current 

 technology. If and when small, long range mortality transmitters are available for ducks, this 

 should be pursued. 



6) What are the characteristics of Harlequin Duck migration? How well defined are migratory 

 staging areas and migration corridors? 



This question may not be tractable given current technology. If and when small, long range 

 mortality transmitters are available for ducks, this should be pursued. Some answers may come 

 from large scale marking of individuals such as in Proposal 1, and perhaps by relocating radioed 

 birds in Proposal 4. 



RESEARCH PROPOSALS TO ADDRESS THE MOST CRITICAL 

 DATA GAPS 



List of Attached Proposals 



1 . Harlequin Duck Population Parameters, Site Fidelity, and Movements 



2. Review of Hydrologic and Geologic Data Availability for Harlequin Duck Breeding Streams in 

 Montana. 



3. Large scale evaluation of characteristics of occupied versus unoccupied Harlequin Duck 



streams in Montana. 



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