Oral Presentation Australian Society of Fish Biology and Oceania Chondrichthyan Society Conference 2016

Contextually-specific variations in white shark activity measured by 3D-acceleration logger (#114)

Charlie Huveneers 1 , Yuuki Watanabe 2 , Nicholas L Payne 2 , Jayson Semmens 3
  1. School of Biological Sciences, Flinders University, Bedford Park, SA, Australia
  2. National Institute of Polar Research, Tokyo, Japan
  3. Fisheries and Aquaculture Centre, Institute for Marine and Antarctic Studies, Hobart, Tasmania, Australia

Wildlife tourism is one of the fastest growing sectors of the tourism industry. White sharks, Carcharodon carcharias, have become a key attraction to wildlife tourism, which often occurs at important shark aggregation areas. In South Australia, the intensity of cage-diving activities more than doubled around 2007 from about 120 days of operations per annum to 265 days. Recent studies assessing the effects of such expansion showed that cage-diving operations can affect the behaviour and residency of white sharks. It is, however, unknown whether such changes are detrimental to sharks. We deployed activity packages encompassing high frequency acceleration and swim speed loggers, depth and temperature recorder, and animal-borne camera to describe the fine-scale behaviour of white sharks at the Neptune Islands and assess whether cage-diving tourism changes the energy expenditure of white sharks due to increased activity. Ten sharks were fitted with activity packages for deployment periods ranging from 30 minutes to ~40 hrs (mean 22 hrs). A range of behavioural modes were recorded and varied between and within individuals. Strong accelerations were observed throughout the day and night. Bait chasing and a natural predation were recorded by the loggers and camera allowing to allocate accelerations and swimming speed to behaviours and compare the energetic cost of activities between these behaviours.