PhD studentship available now:
MIGRATION OF CARIBOU IN THE CANADIAN ARCTIC

Closing Date for applications is: 31 August 2001

The mechanisms responsible for migratory behaviour of large herbivores may include 1) forage availability, 2) predation by carnivores, 3) risk of parasitic infections. In the Arctic, caribou have to contend with the problem that, for most of the year, access to forage is restricted by snow and ice, while in the summer because above-ground plant biomass is typically low, caribou may trade-off forage quality for quantity. Thus migration may enhance the exploitation of patches of forage that cannot be occupied year round either because of restricted access in winter or risk of over-grazing. Also, an additional benefit of migrating to seasonally available pastures may be to reduce transmission of gastro-intestinal nematodes, which depress body condition and fitness. Finally, in some situations, for example, caribou wintering in the taiga forest and calving on the tundra, migration may reduce the risk of predation by moving beyond the feeding range of wolves concentrated close to denning sites at the tree-line.

A three-year PhD studentship is available to investigate the influence of forage quantity and quality, and risk of parasitism on caribou migrating between calving grounds on Victoria Island, Nunavut, Canada (70ºN, 110ºW), and wintering on the mainland, in the vicinity of Bathurst Inlet. The student will undertake field observations of feeding behaviour of satellite-collared caribou in summer and winter ranges, in order to relate diet selection to measures of plant species abundance and quality. Counts of nematode eggs in caribou faeces will provide indices of parasite burden calibrated against adult and larval nematode worm counts in harvested caribou, and correlated to body condition. Experiments to establish risk of parasitic infection will investigate development from nematode eggs through free-living stages to infective larvae in different plant communities in the summer and winter ranges. Knowledge of these interactions is crucial to understanding the mechanisms driving migratory behaviour.

The studentship, funded by the Government of Nunavut, Canada, will start as soon as possible in autumn 2001 and lead to a PhD from the University of Aberdeen, Scotland. It will involve fieldwork in all seasons, except November-February, and periods in Aberdeen, working within both the University of Aberdeen Department of Plant and Soil Science and the Centre for Ecology and Hydrology, Banchory. Candidates should have either a good first degree or MSc in an ecological science. Candidates must be physically fit, and able to work in arduous conditions in very remote locations. Field experience in the Arctic would be an advantage.
The closing date for applications is 31 August 2001. Individuals who responded to an earlier advert should not re-apply.

For further details, please contact:

Steve Albon
Centre for Ecology and Hydrology, Banchory, AB31 4BW, Scotland
(s.albon@ceh.ac.uk)

Sarah Woodin,
Department of Plant and Soil Sciences, University of Aberdeen, Scotland
(s.woodin@abdn.ac.uk)

Fieldwork

The amount and exact timing of periods of fieldwork will be decided as the project develops. However, we envisage that up to six months per year may be spent on fieldwork. During July and August this will involve studies of the feeding ecology of musk ox (potential competitors of caribou), including observation of foraging behaviour, identification of preferred plant species, and description of the plant communities utilised. Additional study of habitat use will be made by dung counts. During September and October when caribou overlap the range used by musk ox, these activities will be undertaken for both species. Indices of parasite abundance for both species will be assessed by counting nematode eggs in faeces, and study of larval development including overwinter survival. Winter fieldwork will involve observations of caribou feeding on windswept ridges and cratering in soft snow pack.

The successful candidate will be involved in culls of animals to assess condition and actual parasite burdens in the intestines.

Fieldwork Logistics

During summer (July-October), fieldwork will be undertaken from a field camp (possibly tents), supported and provisioned from Cambridge Bay, Victoria Island. Cambridge Bay will be up to half a days travel by quad bike/snow scooter from the camp site. Daily communication from the field camp will be by HF radio only; telephone/fax/email access are available in Cambridge Bay. Shorter periods may be spent in field camp on the mainland (Bathurst Inlet) during the winter (March/April). A research assistant/buddy will be provided for safety and help in the field.

The applicant should have proven ability to work long hours in arduous conditions in the field. They must be willing and able to drive a quad bike and snowmobile, and happy to use a gun for personal safety.

Laboratory Work in Aberdeen (November-February, May-June)

This will involve processing of animal gut samples to quantify parasite burden at a species level. There will also be basic chemical analysis of plant material from the field studies of forage selection. The study has access to satellite images of the region and daily information on the location of satellite collared caribou. The opportunity thus exists to exploit these data sources in a study of the distribution of caribou in relation to habitat type over a much wider area and time frame.