Broseth, H. & Pedersen, H.C. Hunting effort and game vulnerability studies on a small scale: a new technique combining radio-telemetry, GPS and GIS. Journal of Applied Ecology 37, 182-190 (2000).

This study combined the use of GPS devices and GIS mapping to look at the effects of hunting on Willow Ptarmigan in Norway.  The novel approach in this study was that in addition to the birds being tracked with radio-collars, the hunters were also tracked via GPS units given to them by the researchers.  The study collected about 50 days of data from the hunters and combined this in a GIS with the locations of radio tagged birds in the hunting area as well as their probable mortality based on radio-tagged birds that were collected by hunters.  This technique was modified from the use of satellites tracking fishing vessels to deduce the impact commercial fishing has on fish populations and inform decisions about fisheries management.  Garmin GPS recivers aere mounted on the hunters backpacks at the beginning of each hunt and were programmed to automatically create a way-point at 1-minute intervals; the hunters also took waypoints at each site of a ptarmigan kill.  These tracks were integrated into a gridded map of the study site and buffered to trepresent the path of a hunter and dog.  The whole area was overlayed with polygos representing individual home-ranges for radio tagged birds, and these intersections were clipped in ArcGIS, allowing a visual representation of the expended effort of a hunter to kill one bird.  The GPS tracks of the hunters were also used to create maps in ArcGIS that display the spatial distribution of hunting pressure for the study area.  This study was a very clever way to link GPS data from two different sources with GIS and take advantage of GIS tools to associate these in a meaningful way.  I will also be looking for the overlap of disparate features that may be influencing what areas of an island that birds use for breeding.