Willow ptarmigans are heavily hunted in most alpine areas of Norway and the populations are known to vary in numbers through time and space. In the recent years, monitoring and density estimates of hunting areas have become an integrated part of an active management. And often used as the (only) basis of management actions like; bag-limits, closing, reduction of hunting pressure etc.  An active use of density estimates in management demand precise estimates to avoid under- or overregulation of the hunting.  In this thesis, I will use line transect survey data to estimate willow ptarmigan densities in hunting areas all over Norway. Relevant covariates to explain detection probability will be used in an attempt to increase precision in the estimates. Further the density estimates will be analyzed to se whether the known variation in density and production can be related to differences in habitats across hunting areas and if the variation in population growth is spatially correlated. Effects of habitat may suggest that hunting areas must be managed differently in different habitats (i.e. possibly treated as source or sink areas). Spatial correlation in population growth may indicate a proper scale of management actions. For future monitoring, I will test, however not on the expense of quality, different methods to reduce the effort in line transect surveys.

Project description



Kvasnes, M. A. J., Storaas, T., Pedersen, H. C., Bjork, S. and Nilsen, E. B. 2010. Spatial dynamics of Norwegian tetraonid populations. - Ecological Research25: 367-374.

Published: .