Behavioural Responses of the Australian Fur Seal (Arctocephalus pusillus doriferus) to Vessel Traffic and Presence of Swimmers in Port Phillip Bay, Victoria, Australia

Abstract

A largely unregulated seal-swim industry exists in Port Phillip Bay, Victoria, Australia. This study has documented four fur seal behaviours in response to vessel traffic and presence of swimmers in order to determine the impact of tourism activities on Australian fur seals (Arctocephalus pusillus doriferus). Behavioural responses of fur seals to the presence of a total of 135 vessels (tour = 61 and recreational = 74) were collected on 42 research trips over the peak austral summer tourist period (November 2007 to February 2008). After considering all studied variables, vessel distance, the number of swimmers undertaking sealswim activities, and the number of recreational vessels were found to influence seal behaviour. Aggressive behaviour displays by fur seals were influenced by the presence of recreational vessels within close proximity to the study site (< 200 m); haul-out events initially increased as a result of the presence of swimmers undertaking seal-swim activities; and occurrences of fur seals entering the water increased in response to the distance of approaching tourism vessels to the study site. Statistical analyses found no clear indicator influencing the number of threat postures displayed by fur seals. While a weak linear relationship was identified between the indicators (i.e., presence of recreational vessels, presence of swimmers, and the distance of tour vessels) and the three behaviours displayed by fur seals, post hoc tests failed to achieve significantly different means for each of the indicators. This preliminary research into the impact of swim-with tourism upon A. pusillus doriferus will provide valuable baseline data for the future. The long-term research into the effects of this particular tourism industry on fur seal behaviour may ensure wildlife managers develop appropriate regulations for seal tourism interactions that promote a sustainable marine tourism industry within Port Phillip Bay.