Size and composition of the wild reindeer Rangifer tarandus platyrhynchus population in the Southeast Svalbard Nature Reserve

Alendal, E., de Bie, S. and van Wieren, S. E. 1979. Size and composition of the wild reindeer Rangifer tarandus platyrhynchus population in the Southeast Svalbard Nature Reserve. Holarct. Ecol. 2: 101-107. In the summer of 1977 we studied the reindeer population on the islands Barentsøya and Edgeøya in the eastern part of the Svalbard archipelago. A total of 1374 reindeer were observed: 326 animals in the western parts of Barentsøya and 1048 animals on Edgeøya. Considering those parts of Edgeøya which were not visited, the total number of reindeer on Edgeøya was estimated at 1300 animals. The total number of reindeer was lower than in previous years. The decline probably was due to severe winter conditions in 1975/1976 and 1976/1977 confirmed by the fact that many carcasses and few yearlings were observed. Nearly all reindeer occurred on the coastal plains and in the valleys. These areas have the relatively richest vegetation. The average recruitment of the total population (counted) was 15.9%. The adult sex ratio was in favour of females: 59% females versus 41% males. There were differences both in the recruitment and in the adult sex ratio between three distinct areas on Edgeøya and between two on Barentsøya. These differences may be due to dissimilarities in food quality and feeding conditions caused by climate, and by small exchange of reindeer between the areas. The high frequency of shed male antlers on Frankenhalvøya and Talaveraflya, north and south coast of Barentsøya respectively, indicates that these areas belong to the wintering grounds of reindeer on this island. Concentrations of shed female antlers on Barentsøya were less pronounced. The highest frequency was in the areas Sjodalen and Kvistdalen-Talaveraflya in the northwest and south respectively. Females may use these areas as late wintering grounds and possibly as calving areas. The average group size was 2.2 and the aggregation index 3.1. Seventytwo per cent of all groups, containing 48% of all reindeer, fell into group size 1 and 2. Males mostly were observed alone or together with one other animal. Females with calves most frequently occurred in groups of 2 and 4 animals.