1. Faculty of Environmental Sciences and Natural Resource Management Norwegian University of Life Sciences Box 5003 Ås 1432 Norway
2. Geo‐Ecology Research Group, Natural History Museum University of Oslo P.O. Box 1172 Oslo NO‐0318 Norway
3. Division of Survey and Statistics Norwegian Institute of Bioeconomy Research (NIBIO) P.O. Box 115 Ås NO‐1431 Norway