IVENSTIGATING THE ACTIVITY OF THE EASTERN ICELANDIC ARCTIC FOX (VULPES LAGOPUS) POPULATION AROUND SKÁLANES NATURAL HERITAGE RESERVE
By Louise McClung. This project is supervised by Dr Stewart White and Dr Ruedi Nager.
The Icelandic arctic fox (Vulpes lagopus), Iceland’s only native terrestrial mammal, is thought to have arrived at the end of the last ice age and has remained genetically isolated from mainland Europe (Mellows, 2012). The arctic fox is well adapted to living in cold weather, with a small surface area to volume ration and thick fur. In Iceland the arctic fox has a stable diet of birds throughout the year and therefore does not experience the short-term population cycles seen in similar populations in other Nordic countries where the foxes predate mostly on lemmings (Unnsteinsdóttir, 2016). Arctic foxes stay in breeding pairs and defend a territory, where they raise a litter of young each summer. Monitoring of the arctic fox population in Iceland is important as in other European countries the population has declined and has not recovered since the fur trade in the 1920s despite full legal protection. Despite heavy exploitation and hunting, along with the attempt to exterminate the population in 1958 to reduce the economic damage to eider and sheep farmers, the arctic fox population has been stable in Iceland (Hersteinsson, 1989).
For this project we will be setting up a monitoring station of arctic fox population and behaviour on the east coast of Iceland. A higher density of the arctic fox is located on the West coast, near the Hornstrandir Nature Reserve, the only area in Iceland where arctic foxes are protected from hunting and there is no permanent human settlement. The Westfjords, where Hornstrandir Nature Reserve is located, also have healthy and successful of seabird colonies. With the information about the Western populations, setting up a monitoring project with Skálanes Nature and Heritage Centre would help to bring knowledge about the populations on the East coast.
For this project we will be looking into the factors affecting the arctic fox’s activity and to find explanations to any patterns we might find, whether it be abiotic influence or prey activity. Understanding the factors that affect the arctic foxes’ activity and therefore success in hunting and rearing young are important for explanations of population change in the foxes or their prey species. Both the foxes and their prey species may be affected by changing temperatures and weather due to anthropogenic climate change; this heightens the importance of establishing baseline data for Skálanes’ arctic fox population.
Hypotheses
- The activity of the arctic foxes during the summer months will be dependent on the activity of its prey species.
- Time of day will have no significant influence on the activity of the foxes due to little change in light intensity.
- Bad weather such as heavy rain, wind, or fog will negatively influence activity and hunting successes.
Aims
- Investigate the activity of the arctic foxes based on time of day, temperature, wind speeds and other abiotic factors that could influence hunting success.
- Observation of the arctic foxes in the Skálanes area. To record the number of individuals, number in each occupied den. Take note of behaviour and family dynamics. The types and variation of prey brought back to the den or observed catching. Comment on the overall health of individuals studied (Fur quality, body condition, size).
- Collection of faecal samples for analysis of prey species.
Methodology
- Locating arctic fox dens and recording the location of occupied dens with the help of Ólafur Pétursson of Skálanes.
- The use of drones with infrared and IR cameras to locate dens further away from the centre.
- Setting up of camera traps at each den location, taking care not to disturb the den or cause unnecessary stress.
- From each den, on each visit collection of faeces or hair samples taken using protective clothing and storing of samples in tubes to be transported back to centre.
- Dens closer to the centre can be monitored more frequently. Depending on battery/memory capacity of camera traps, further away dens will be visited less frequently.
- When the dens are abandoned at the end of the summer, examination for sample collection.
Refernces
Hersteinsson, P., Angerbjörn, A., Frafjord, K. and Kaikusalo, A. (1989). The arctic fox in fennoscandia and Iceland: Management problems. Biological Conservation, 49(1), pp.67-81.
Mellows, A., Barnett, R., Dalén, L., Sandoval-Castellanos, E., Linderholm, A., McGovern, T., Church, M. and Larson, G. (2012). The impact of past climate change on genetic variation and population connectivity in the Icelandic arctic fox. Proceedings of the Royal Society B: Biological Sciences, 279(1747), pp.4568-4573.
Unnsteinsdóttir, E., Hersteinsson, P., Pálsson, S. and Angerbjörn, A. (2016). The fall and rise of the Icelandic Arctic fox (Vulpes lagopus): a 50-year demographic study on a non-cyclic Arctic fox population. Oecologia, 181(4), pp.1129-1138.