Wolves (Canis lupus) are on the endangered species list in several states. This long-term study uses Very High Frequency (VHF) and Global Positioning Satellite (GPS) radio collars to elucidate several aspects of wolf ecology and behavior. The backbone of the project is the monitoring of the wolf population trajectory over the long term. Members of 8–12 wolf packs in a standard study area are located weekly by GPS and/or aerial VHF tracking, and each year in winter the numbers in each pack are aerially counted. After peaking in 2009, the population declined by 60% by 2015, probably as a result of a major decline in the numbers of moose and deer, which comprise a major portion of the wolf diet.