|Peregrine Falcon Research At Rankin Inlet: History and Future Outlook
Research on the ecology and toxicology of tundra peregrine falcons (Falco peregrinus tundrius) was conducted at Rankin Inlet, Nunavut between 1980 and 2000; less intensive work involving monitoring of population size and productivity has been conducted since 2000 (summary by Setterington 2003). This research was motivated initially by the need to understand processes responsible for a worldwide decline in peregrine falcon populations, most notably those caused by widespread DDT contamination (Cade et al. 1988). The population at Rankin Inlet provided a unique opportunity for studying trends in toxic chemical pollutants in this predator and also enabled investigation of the basic biology of the species. Rankin Inlet is ideal for this type research as the peregrine nesting density is particularly high (up to 30 pairs/450km2), nest sites are relatively accessible, and field logistics are relatively simple and inexpensive.
In 1995, the United States Fish and Wildlife Service down-listed F.p. tundrius from the U.S. Endangered Species List because of perceptions of improving pesticide conditions in these northern falcons. The Committee on the Status of Endangered Wildlife in Canada (COSEWIC) downgraded the status of the northern subspecies to Species of Special Concern in 1992, also as a result of perceptions of improvement in pesticide loads in these birds. However, work by Johnstone et al. 1996 at Rankin Inlet found little improvement in such conditions as measured a decade earlier in the same population. Moreover, Johnstone concluded that while peregrines were still accumulating organochlorine pesticides on their wintering grounds, significant residues were also being accumulated by consuming aquatic prey species that range only within North America. Recent discovery of high levels of brominated diphenyl ethers (BDEs), (compounds released to the environments in brominated fire retardants) in the tissues of peregrine falcons in Sweden has led to speculation that summit predators, like falcons, may now face threats from yet another group of anthropogenic pollutants.
Opportunity currently exists to re-sample pollutant loads in the Rankin Inlet peregrine population and to investigate new toxicological threats. This would result in accruing data in a third and consecutive decade, the first to be undertaken post de-listing, and would constitute the longest ongoing study of organochlorine trends in a population of peregrine falcons anywhere in the world. At present, we have a post-doctoral student who is interested in taking advantage of this research opportunity who has applied to the Natural Sciences and Engineering Research Council (NSERC) for a Post-doctoral Award. This applicant has sought the position at the University of Calgary. It is planned that toxicological work would be done in collaboration with researchers at Agriculture Canada, in Saskatoon, the same collaborators (and same lab) in earlier work (Court et al. 1990, Johnstone et al. 1996).
Primary Research Objectives 2004-2006:
The primary objective of this study is to broaden the toxicological analysis of peregrines at Rankin Inlet using field sampling procedures and toxicological measures developed by Court et al. 1988 and later employed by Johnstone et al (1996) in the early 1990s. The research would focus on comparing existing data on organochlorine residues in peregrine egg contents, peregrine blood plasma, and prey species (early 1980s, early 1990s) with that from similar samples taken since 2000 and through 2006. Although such work would investigate the hypothesis that banning the use of ‘high profile’ organochlorines (e.g. DDT) in industrial nations predicts decadal declines in contamination levels in the study population, there also exists the potential to detect trends in BDEs in the tissues of peregrines from the Rankin Inlet study population.
Additional Research Opportunities 2004-2006
Earlier research at Rankin Inlet established demographic parameters (Court et al. 1989, Johnstone 1996) essential to the construction of population projection models. Long-term data from Rankin Inlet have been instrumental in demonstrating the effects of climatic conditions and food supply on reproductive performance (Johnstone 1996, Bradley et al. 1997). Using these data, we hope to develop stochastic population projection model to simulate population trends under varying scenarios. Our final objective is to record morphometric information on adult tundra peregrine of both sexes and compare these data to the extensive data-bases of anatum peregrines and pealei peregrines compiled by researchers in other parts of North America. A meta-analysis of this form should result in sufficient statistical power to shed new light on morphological differences between the 3 North American sub-species, something that is now necessary considering efforts to continue to classify and manage these three populations as separate entities.
(and Additional Publications
On Peregrine Research at Rankin Inlet)
Bradley, D.M. 1989. Factors affecting the reproductive success of peregrine falcons in Rankin Inlet,
N.W.T. M.Sc. Thesis. University of Saskatchewan, Saskatoon.
Bradley, D.M., Johnstone, R.M., Court, G.S. and T. Duncan. 1997. Influence of weather on
breeding success of Peregrine Falcons in the Arctic. Auk 114:786-791.
Bradley, D.M. and L.W. Oliphant. 1991. The diet of peregrine falcons at Rankin Inlet,
Northwest Territories: an unusually high proportion of mammalian prey. Condor 48: 101-116.
Cade, T.J., Enderson, J.H., Thelander, C.G. and White, C.M. (eds.) 1988. Peregrine Falcon populations:
their management and recovery. Proceedings of the International Peregrine Conference, Sacramento, l985. Braun–Brumfeld, San Francisco. pp. 729–739.
Court, G.S. 1986. Some Aspects of the Reproductive Biology of Tundra Peregrine Falcons.
(Falco peregrinus tundrius). M.Sc. 1986. University of Alberta, Edmonton.
Court, G.S., Gates, C.C., Boag, D.A., MacNeil, J.D., Bradley, D.M., Fesser, A.C.,
Patterson, J.R., Stenhouse, G.B., and Oliphant, L.W. 1990. A toxicological assessment of
peregrine falcons (Falco peregrinus tundrius) breeding in the Keewatin District of
the Northwest Territories, Canada. Canadian Field–Naturalist 104(2):255–272.
Court, G.S., Bradley, D.M., Gates, C.C., and Boag, D.A. 1989. Turnover and recruitment in a
tundra population of peregrine falcons Falco peregrinus. Ibis 131:487–496.
Court, G.S., Bradley, D.M., Gates, C.C., and Boag, D.A. 1988. The population biology of
peregrine falcons in the Keewatin District of the Northwest Territories, Canada.
In: Peregrine Falcon populations: their management and recovery.
Proceedings of the International Peregrine Conference, Sacramento, l985.
Cade, T.J., Enderson, J.H., Thelander, C.G. and White, C.M. (eds.)
Braun–Brumfeld, San Francisco. pp. 729–739.
Court, G.S., Gates, C.C., and Boag, D.A. 1988. Natural history of the peregrine falcon in the
Keewatin District of the Northwest Territories. Arctic 41: 17–30.
Duncan, T.A. 1993. Diet of peregrine falcons during the nestling stage: a comparison of diet
sampling techniques. M.Sc. Thesis. University of Saskatchewan, Saskatoon.
Johnstone, R.M. 1997. Aspects of the population biology of tundra peregrine falcons
(Falco peregrinus tundrius). Ph.D. Thesis. University of Saskatchewan, Saskatoon.
Johnstone, R.M., Court, G.S., Fesser, A.C, Bradley, D.M., Oliphant, L.W., and J.D. MacNeil.
1996. Long-term trends and sources of organochlorine contamination in Canadian
tundra peregrine falcons, Falco peregrinus tundrius. Environmental Pollution 93:109-120.
Johnstone, R.M., Wetton, J.H., Bradley, D.M., Court, G.S., Parkin, D.T., and Oliphant, L.W.
In press. Parentage of peregrine falcon broods as determined by minisatellite
and microsatellite DNA profiling. Journal of Behavioural Ecology and Sociobiology.
Millsap, B.A., Kennedy, P.L., Byrd, M.A., Court, G.S., Enderson, J.H., and R.N. Rosenfield. 1998.
Review of the proposal to de-list the American peregrine falcon. Wildlife Society