The behavioural response of lactating Weddell seals (Leptonychotes weddellii) to over-snow vehicles: a case study

Over-snow vehicles are used extensively at Antarctic scientific research stations. Adult female Weddell seals (Leptonychotes weddellii (Lesson, 1826)) also utilise the fast-ice and are therefore often exposed to vehicular activity, with the potential of affecting their behaviour. Guidelines for vehicular travel have been developed to minimise disturbance to Antarctic wildlife; however, these guidelines have not yet been scientifically tested. To examine the efficiency and sensitivity of existing guidelines used within the Australian Antarctic Territory (AAT), we conducted drive-by experiments of two types of over-snow vehicles. The results of these experiments showed that the probability of a lactating Weddell seal looking at the vehicles and the duration of the seals' looking at the vehicles were dependent on the distance between vehicles and seals, the position of the pups in relation to its mother, and the distance the adult female was from the water. Although the seals apparently perceived the vehicles to be a threat, no seals fled in response to vehicle activity. We propose that the existing guidelines used in the AAT could be amended to increase separation distances between vehicles and breeding Weddell seals if the goal of management is to ensure that Weddell seal behaviour is unaffected by vehicle travel. © 2007 NRC.