Inventering av varg vintern 2019–2020

• Main Authors: Wabakken, Petter, Svensson, Linn, Maartmann, Erling, Nordli, K., Flagstad, Öystein, Åkesson, Mikael
• Format: Report
• Language: English; Swedish
• Published: 2020
• Subjects: Ecology; Norway; Northern Sweden
• Online Access: https://pub.epsilon.slu.se/22134/; https://pub.epsilon.slu.se/22134/1/waabakken_p_et_al_210205.pdf

Monitoring goals and methods: Wolves in Sweden and Norway are members of a joint cross-boundary Scandinavian wolf population. In both countries, the wolf population is being monitored each winter. The Swedish Environmental Protection Agency and the Norwegian Environment Agency have joint Scandinavian guidelines and instructions for monitoring of wolves; these guidelines have been used since winter 2014-2015. Numbers, distribution and trends in the wolf population in Scandinavia are primarily determined through a survey of family groups, scent-marking pairs and reproductions during 1 October - 31 March. The survey of wolves is done mainly through snow-tracking and DNA-analyses of scats, urine and hair. Information from GPS-collars, other research data and dead wolves are used when available. The County Administrative Boards in Sweden and the Norwegian Nature Inspectorate (SNO) together with Inland Norway University of Applied Sciences in Norway are responsible for collecting field data. They also confirm reports of tracks and other observations by the public. For the wolf monitoring, contributions from the public are very important. Number of family groups and scent-marking pairs: During winter 2019-2020, 45 family groups were documented in Scandinavia; 34 within Sweden, five across the Norwegian-Swedish border and six within Norway. 26 territorial pairs were confirmed; 17 within Sweden, four across the border and five within Norway. Population size: Using the same method as last winter and based on the number of reproductions (the number of reproductions is multiplied by 10), Scandinavian wolf numbers were estimated to 450 (95% CI = 356-585). The Swedish sub-population was estimated to 365 wolves (95% CI = 289-474), including half of the cross-boundry wolves. The calculation includes both alive and dead wolves during the monitoring period. In the smaller Norwegian sub-population, 80-81 wolves were counted directly in the field, including half of the 47-50 cross-boundary wolves and 56 wolves confirmed only in Norway. Genetics: One previously known Finnish-Russian female wolf was still resident within the populations breeding range (Örebro County), where she raised a F1-litter of pups born in 2019. Another previously known Finnish-Russian male was observed in northern Sweden, outside the breeding range. In addition, three new Finnish-Russian immigrant wolves were confirmed in Scandinavia, all roaming males, but one was captured, collared and translocated to the south in Norway. He later settled as part of a territorial pair in Norway. In addition, 14 older F1 offspring from three known Finnish-Russian immigrants were confirmed in Scandinavia, including eight F1 as scent-marking adults in family groups or pairs. The estimated average inbreeding coefficient in family groups was 0.24 (0.09 SD) this winter, a slight decrease compared to last years monitoring season (0.25 ± 0.09 SD).