Focal Species in Tundra Systems: Gyrfalcon, Willow Ptarmigan
Established: Ongoing since 1970. Database extends from mid-1950's.
Long-term data bases track changes in the population parameters of the top predator (gyrfalcon) and the keystone prey (willow ptarmigan).
Three study areas spaced north to south across the Yukon are surveyed annually. Breeding density, and productivity are the key variables along with breeding chronology. Ground search in late winter is used to survey ptarmigan, air survey to known nest sites tracks gyrfalcon numbers. Various Yukon College students assist.
Ongoing reports and publications cover significant details and trends. Currently evidence points to a disruption to normal population cycling and suggests a declining overall trophic response in the system.
2011 The overwhelming influence of ptarmigan abundance on gyrfalcon Reproductive success in the central Yukon, Canada. In: R.T. Watson, T.J. Cade, M. Fuller, G. Hunt, and E. Potapov (Eds) Gyrfalcons and Ptarmigan in a changing world. The Peregrine Fund publ.
2011 Long-term studies of willow ptarmigan and gyrfalcon in the Yukon Territory: a collapsing 10-year cycle and its apparent effect on the top predator. In: R.T. Watson, T.J. Cade, M.Fuller, g. Hunt and E. Potapov (Eds). Gyrfalcon and Ptarmigan in a Changing World. The Peregrine Fund Publ. Boise.
2008. Willow and Rock ptarmigan density estimates – Northern Yukon 1975- 2008. IPY project report (W.O.L.V.E.S.) N.Res. inst ms, Yukon College.
Department of Environment, Government of Yukon
Ministry of Environment, Government of British Columbia
Base funding from:
Parks & Conservation AND Fish and Wildlife Branch, Department of Environment, Government of Yukon
International Polar Year
As well as annual proposals made to various sources.