The investigations of reindeer were conducted in cooperation with J. Kumpula of the Finnish Institute for Wildlife and Fish Research (Kaamanen), A. Colpaert from the Institute of Geography
of the University of Oulu, and R. Schulte from the Institute for Air and Space Flight of the TU Berlin.
Methods and Goals
Reindeer have in the past as well as in the present played an important role in the lives of the Samen people living in the north of Finnland. The reindeer
have long since been domesticated, with only few wild ones remaining. The reindeer graze freely for the entire year, and are normally only herded together during the few days in fall or in spring to brand
young animals or for slaughtering. Fig. 1 shows reindeer in the corrals in the investigation area.Herethe animals were selected and provided with transmission collars.
Fig. 1: Reindeer during selection in the corrals, November 1997
During the year the reindeer wander long distances in search of good pasture. In the summer the
animals migrate to windy mountain areas above the treeline to flee biting insects. The population of reindeer in northern Finnland has increased in recent years so that the danger of overgrazing is
prevalent. As these northern ecosystems are very sensitive and take a long time to regenerate from adverse changes, a detailed knowledge of the seasonal habitat utilization of the reindeer is imperative.
The investigations were conducted in a mountainous region, usually above timberline in northwest Finnland in the vicinity of the Norwegian border (Figs. 1 and 2).
Fig. 2: Location of the investigation area in Finnland (red symbol)
Goal of the presented investigation was to determine the seasonal utilzation of pasture among the
reindeer. For this purpose their locations throughout the year were to be determined and monitored with the aid of satellite telemetryand analyzed as part of a geographical information system using
Landsat-5 photographs of the vegetation cover. In 1997for the first time 4 male and 6 female reindeer were outfitted with GPS collars which were to determine their locations 3-8 times per day (Fig. 3).
Fig. 3: Reindeer in the corrals, with GPS-TUBSAT collar Photo: Jouko Kumpula
Three of the GPS collars were constructed in such a way that the position data of these reindeer
could be transmitted directly via the experimental satellite TUBSAT-A to the ground station in Berlin
(see Nr. 2 The Beginnings: Pilot studies of red deer). The GPS collars were also provided with a radio transmitter so that the animals could be localized in Finnland.
The GPS collars determined 3994 localizations of the reindeer, the functional periodvaried between
22 and 227 days. Based on the number of possible localizations, the actual rate of localization was 0.79, which was neither dependent on the vegetation cover nor on the season. The male animals
mainly migrated in early winter to graze in bare, lichen covered mountain areas with a thin snow blanket. Fig. 4 shows the migrations of two reindeer.
Fig. 4. Position points of reindeer Nrs. 48 and 49, Permission Nr.116/MYY/99, Finnish Land Survey
W it h in cr e a si n g snow cover in winter the male reindeer decreased their wanderings, concentrating in ever smaller
areas. In late winter when the snow cover turned harsh they moved to mountain birch forests where the snow was softer, and browsed lichens and buds from the trees. In May the animals were
frequentlyto be found in heathlands.
The longest migrations took place during the summer months. From August until September they travelled to various pastures depending upon the available browse supply.
The satellite telemetry proved to be an effective method to monitor the migrations of the reindeer.
However, various technical problems were encountered in the use of the GPS collars: Though the transmission of position data via TUBSAT-A was successful, the collars having a weight of 1.5 kg.
were too heavy. Also water seeped into some of the instruments which later proved to be due to a non-suitable composition of the casing material. Finally the shape of the case housing the
electronics and batteries was inappropriate and needs to be improved since snow accumulated on some of the cases while the animals were grazing, further increasing the weight of the collars.
These problems were solved in subsequent years, and VECTRONIC-Aerospace designed new GPS collars specially for reindeer, which were tested with good results in actual studies by the Finnish
Institute of Wildlife and Fish Research.