Assessing the number of individuals in a wolf population is based on high-quality data obtained from fieldwork and a method derived from wolf biology.

The assessment of wolf populations is based on observations reported by hunters (tracks on snow), confirmed by large carnivore contact persons and entered in the TASSU large carnivore observation system (TASSU is Finnish for ‘paw’), and on the satellite monitoring of wolves fitted with a radio collar, as well as knowledge of wolf biology and territorial behaviour. If the average size a wolf pack’s territory is known (ca. 1,100 km²) then, coupled with the fact that a wolf pair will not tolerate other individuals in its territory, this information is combined with observations and data obtained from satellite monitoring, enabling researchers to create a picture of the pack and its location.

The number of individuals in a pack can be determined by following the snow tracks it leaves behind for a sufficient length of time. This ensures that individuals are not counted twice.

Data on individual wolves is also obtained through DNA analysis. If the number of excrement samples is sufficient, DNA analyses helps to provide a more detailed picture of the number of wolf territories in a particular area, the number of packs and the number of individuals within them. The reliability of the information produced by this method depends on how comprehensive sampling has been.

A more detailed understanding of the regional size and distribution of the wolf population can be achieved by carrying out separate counts in which hunters, nature enthusiasts and researchers from the Natural Resources Institute Finland count the number of individuals in a specific area during a single day. Such counts also provide baseline information for assessing the accuracy of population counts. To date, assessments produced using the two methods have been a close match, providing a metric for assessing the reliability of population assessments.

Picture on top of the page: Ville Heikkinen/Vastavalo.fi