The Arctic fox is heading for a good year, from Sylane to Saltfjellet. The populations in the far north and south of our long and narrow country have struggled to reproduce. The access to lemmings and rodents is essential for this critically endangered mammal.
As of 19th August, the national surveillance programme for Arctic foxes has registered 34 litters, distributed from Finse in the south to the inner part of Troms in the north. In total the litters consist of a minimum of 178 puppies. Two thirds of the litters have been born in North Trøndelag (11) and Nordland (12), and 116 puppies have been documented in these counties.
"The Arctic fox subsists in the main on lemmings and rodents. A combination of good access to these types of prey and additional feeding over several years explains why the Arctic fox has been successful in rearing puppies in these counties. In total, 2015 therefore looks to be a productive year for the Arctic fox," says Department Manager Yngve Svarte of the Norwegian Environment Agency.
When there are lots of lemmings and rodents the Arctic fox has large litters (8-16), and similarly few or no litters when access to this source of nutrition is poor. This year the stocks of prey have been low or non-existent in most of the mountain areas of Southern Norway, and from Dovre southward only 5 litters have been registered so far. Despite relatively many rodents in Troms and Finnmark, there are only two litters of Arctic foxes registered in the inner area of Troms and none in Finnmark.
"The situation in Troms and Finnmark is a cause for concern. There have been very few litters in these areas in recent years. This is linked to low stocks of Arctic foxes in these two counties, and at the same time small numbers of lemmings in these areas this year," says Svarte.
The number of Arctic foxes in Norway fell dramatically around 1900 due to hunting. The Arctic fox became a protected species in 1930, but the population did not increase. The reason is complex, but the climatic change appears to influence the cycles of lemming and rodent stocks in several mountain areas. Small and sporadic animal stocks are vulnerable in cases of unstable access to food, and in addition the red fox has been observed further into the high mountains than previously.
In an attempt to rescue the Arctic fox, the breeding programme for Arctic foxes was established, including a breeding station at Oppdal. Through this breeding programme, puppies were released over several years at Dovrefjell, Finse and in the southern area of Hardengervidda, where the Arctic fox was extinct. Along with additional feeding, this has lead to the Arctic fox establishing itself again in these areas.
This year it is only Finse that has produced well in the south, even though the litters are small. This is due to a local increase of rodents and lemmings in this area. Arctic foxes have also been released in Junkeren in the municipality of Rana, including the provision of automatic feeding stations over several years. This has led to a strengthening of the animal stocks at Saltfjell.
"We observe larger and more litters at Saltfjell, and the population has gone from being critically low to becoming more robust during the last few years. This shows that feeding is a very important supplement to ensure that the puppies and adult animals survive during years with low or moderate numbers of lemming and rodents, " says Svarte.
Through the Interreg project Felles Fjellrev (Shared Arctic Foxes), the feeding of Arctic foxes and culling of red foxes commenced in central Norway and Sweden, in order to re-establish the stocks of Arctic foxes in these areas. Combined with good access to rodents and lemmings, these measures have resulted in record levels of litters in many places this year. Tydal and Lierne are good examples.
The Norwegian Environment Agency's goal is to ensure the survival of the Arctic fox in the long term. This means we wish to generate a viable animal population, where there is a regular exchange of Arctic foxes between the different mountain areas.
"The breeding programme for Arctic foxes and the Interreg project Felles Fjellrev, as well as the measures that are carried out through these projects, are essential in order to reach our goal. It will be natural to stop the measures in areas where the Arctic fox has been re-established and to start other measures in other areas, until the population in Norway is viable," says Yngve Svarte.
Carrying out the surveillance programme for Arctic foxes and measures to increase the population demands an extensive apparatus. It consists of the Norwegian Environment Agency field apparatus, the Directorate for Nature Management (SNO) and the Norwegian Institute for Nature Research (NINA), together with community owned common land administration, local administration committees for user rights and the land use management authorities. The efforts of these are essential in following-up the individual measures and the project.
Jan Paul Bolstadsenior adviser at the wildlife divisionphone no.: +47 950 60 608