GPS tracking of red foxes in Varanger Peninsula
1 Purpose
Red foxes have shown a dramatic northward shift in their distribution during the last century, and have increased in abundance on the low arctic tundra. There, they threaten essential ecosystem processes through competition and predation on arctic-adapted species like arctic foxes and ground nesting birds. In order to conserve this unique ecosystem we must understand the mechanisms leading to the survival and expansion of red fox populations in tundra habitats.
In this research we aim to track the movements of red foxes on Varanger Peninsula, Northern Norway, using GPS collars. This will inform us about the habitats and resources that red foxes use.
2 Distress
We will trap red foxes in baited wooden box traps and foot snares that are remotely observed with automatic cameras. Upon warning from the automatic camera, trapped foxes will usually be handled within 1 hour (maximum time 13 hours). An additional capture method is by use of a large fishing net from a snowmobile. Captured foxes restrained and equipped with a 170 gram GPS collar (<4.5% bodyweight), and coloured ear tags within 15 minutes. Anaesthesia will not be used during this procedure, which will therefore only cause short-term mild pain, suffering or distress. Once foxes are released, the lightweight permanent GPS collar is expected to cause minimal weakening of the animals and we expect no change in activity and behaviour over a multi-year period. Ear tags will have no long-term effect on the health or behaviour of the foxes.
3 Expected benefit
This research will help management efforts to understand the anthropogenic, environmental, and climatic factors driving the northward expansion of red foxes. More specifically, it will provide us with valuable information regarding the mechanisms underlying the establishment of red foxes in tundra habitats of Northern Fennoscandia. This knowledge is needed to effectively control red fox populations and to understand the effects that red foxes can have on the ecosystem in which they establish. Ultimately this will help to conserve the unique low-Arctic tundra in northernmost Norway.
4 Number of animals, and what kind
A total of 40 red foxes will be trapped and equipped with a GPS collar and ear tags for life.
5 How to adhere to 3R
Replacement: Our research questions can only be answered by gaining insight into fine-scale spatiotemporal movement behaviour of red foxes in the wild.
Refinement: By using a GPS-collar below 4.5% of bodyweight of the smallest fox (3% for the average fox), we will minimise any potential negative effects on the foxes.
Reduction: We will use a reliable GPS collar system that is being used with success on arctic and red foxes by colleagues in Russia. We therefore expect a low rate of technical failure, allowing us to reduce our sample size. A drop-off function is not used since premature drop-off would require a larger sample size. Furthermore, combining the telemetry study with a mark-recapture study using camera traps allows us to answer additional research questions with the same sample of foxes.
Red foxes have shown a dramatic northward shift in their distribution during the last century, and have increased in abundance on the low arctic tundra. There, they threaten essential ecosystem processes through competition and predation on arctic-adapted species like arctic foxes and ground nesting birds. In order to conserve this unique ecosystem we must understand the mechanisms leading to the survival and expansion of red fox populations in tundra habitats.
In this research we aim to track the movements of red foxes on Varanger Peninsula, Northern Norway, using GPS collars. This will inform us about the habitats and resources that red foxes use.
2 Distress
We will trap red foxes in baited wooden box traps and foot snares that are remotely observed with automatic cameras. Upon warning from the automatic camera, trapped foxes will usually be handled within 1 hour (maximum time 13 hours). An additional capture method is by use of a large fishing net from a snowmobile. Captured foxes restrained and equipped with a 170 gram GPS collar (<4.5% bodyweight), and coloured ear tags within 15 minutes. Anaesthesia will not be used during this procedure, which will therefore only cause short-term mild pain, suffering or distress. Once foxes are released, the lightweight permanent GPS collar is expected to cause minimal weakening of the animals and we expect no change in activity and behaviour over a multi-year period. Ear tags will have no long-term effect on the health or behaviour of the foxes.
3 Expected benefit
This research will help management efforts to understand the anthropogenic, environmental, and climatic factors driving the northward expansion of red foxes. More specifically, it will provide us with valuable information regarding the mechanisms underlying the establishment of red foxes in tundra habitats of Northern Fennoscandia. This knowledge is needed to effectively control red fox populations and to understand the effects that red foxes can have on the ecosystem in which they establish. Ultimately this will help to conserve the unique low-Arctic tundra in northernmost Norway.
4 Number of animals, and what kind
A total of 40 red foxes will be trapped and equipped with a GPS collar and ear tags for life.
5 How to adhere to 3R
Replacement: Our research questions can only be answered by gaining insight into fine-scale spatiotemporal movement behaviour of red foxes in the wild.
Refinement: By using a GPS-collar below 4.5% of bodyweight of the smallest fox (3% for the average fox), we will minimise any potential negative effects on the foxes.
Reduction: We will use a reliable GPS collar system that is being used with success on arctic and red foxes by colleagues in Russia. We therefore expect a low rate of technical failure, allowing us to reduce our sample size. A drop-off function is not used since premature drop-off would require a larger sample size. Furthermore, combining the telemetry study with a mark-recapture study using camera traps allows us to answer additional research questions with the same sample of foxes.