Vigilance and fright behaviour in the insular Svalbard reindeer (Rangifer tarandus platyrhynchus)

Abstract

The insular Svalbard reindeer ( Rangifer tarandus platyrhynchus Vrolik, 1829) provide an opportunity to study vigilance behaviour in the absence of predators and parasitizing insects. We measured vigilance and fright and flight response during summer 2006 in the Svalbard archipelago; in four areas on Nordenskiöld Land on the island Spitzbergen and in one area on the island Edgeøya. Vigilance was higher in reindeer on Edgeøya than in the four Spitzbergen areas. Males were less vigilant than lactating and barren females and vigilance decreased with increasing group size. The relaxed vigilance behaviour in Svalbard reindeer compared with wild reindeer in southern Norway demonstrates a vigilance threshold in the absence of traditional predators of Rangifer Hamilton Smith, 1827. Alert, flight initiation, and escape distances were all shorter in Adventdalen, with Longyearbyen and its considerably higher amounts of human activities and infrastructure than in the other study areas, supporting evidence of habituation towards humans. There were no systematic vigilance or differences in fright and flight responses between reindeer in Colesdalen, Reindalen, and Sassendalen, indicating that a combination of low level of human activities including hunting, recreation, and scientific activities affected the animals differently. Lower probability of assessing before fleeing in Edgeøya (63% vs. 94% in the Nordenskiöld Land areas), along with their higher vigilance, may indicate more frequent interactions with polar bears ( Ursus maritimus Phipps, 1774) in Edgeøya.