Natural Resources Institute Finland (LUKE) has followed the movements and habitat selection of wild forest reindeer using GPS collars since 2006. During this 10-year monitoring period more than 200 wild forest reindeer does have been fitted with collars. Only does are collared because stags’ necks swell up during the rut, i.e. when they are in heat, which prevents the safe use of collars.

The number of collared individuals will be increased during the WildForestReindeerLIFE project. The aim is to collar nearly eighty wild forest reindeer does during the project (2016–2023). Collaring will be performed in both Kainuu and Suomenselkä. A few individuals belonging to the Ähtäri subpopulation will also be fitted with monitoring collars.

In addition to wild individuals, certain does relocated to the on-site enclosures during autumn 2017 have also been collared. Positioning information from the collars can be used to follow the spatial utilization of wild forest reindeer in the on-site enclosures, and track them in the unlikely event that they manage to escape despite all our precautionary measures. At a later date collars will also be fitted on individuals released from the enclosures. In this way we can follow how the wild forest reindeer are settling into their new habitats.

The monitoring collars provide valuable new information on wild forest reindeer behavior. Following the habitat selection of collared animals provides us with information that can be utilized e.g. when choosing peatland sites for restoration. In a similar manner, monitoring collared individuals helps in identifying their most important winter pastures. In this way lichen-conserving silvicultural measures can be targeted in the right areas.

Collar monitoring also provides information on wild forest reindeer mortality rates and factors. Predation by wolves is the most notable cause of death for collared does. Monitoring has also showed that most wild forest reindeer does in Kainuu do calve, but the calves do not survive as far as autumn.

The GPS collars are uncovering information that otherwise would probably have remained unnoticed for a long time. For example, the seasonal migration distances of the Suomenselkä wild forest reindeer population have increased in recent years, and they now migrate up to Lake Oulujärvi, bringing them close to the reindeer herding area. This change in migration patterns would have gone unobserved without the help of technology. Now we can search for solutions to the increasing risk of wild forest reindeer hybridizing with reindeer, which is made possible by their lengthening migration route.

Collared individuals also aid in wild forest reindeer population size estimation. Wild forest reindeer form herds during winter. When the location of collared individuals is known, aerial counts can be directed to the correct areas. This saves precious flight hours and increases counting certainty.

Information concerning the movements of collared animals can also be used to prevent wild forest reindeer traffic collisions. Once their seasonal migrations begin, road users can be warned more effectively of the increased collision risk. Also, if the winter pasture of a herd lies near a heavily trafficked road, collared individuals can be used to gather information on road-crossing routes. This information can be passed on to warn road users.

Picture: Collar monitoring produces information e.g. on the calving success and calf survival of wild forest reindeer. (Photography: Pekka Kilpeläinen)

Info Box

Wild forest reindeer

Scientific name: Rangifer tarandus fennicus

Range and numbers:

In Finland, 800 individuals in Kainuu, 2000 individuals in Suomenselkä and about 20 individuals in Seitseminen and Lauhanvuori National Parks (reintroduced populations).

In Russian Karelia up to 2,400. See range map.

Conservation status in Finland (2019): Near Threatened (NT)