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In the dive tourism industry, shark provisioning has become increasingly popular in many places around the world. It is therefore important to determine the impacts that provisioning may have on shark behaviour. In this study, eight adult whitetip reef sharks Triaenodon obesus were tagged with time-depth recorders at Osprey Reef in the Coral Sea, Australia. Tags collected time and depth data every 30 s. The absolute change in depth over 5-min blocks was considered as a proxy for vertical activity level. Daily variations in vertical activity levels were analysed to determine the effects of time of day on whitetip reef shark behaviour. This was done for days when dive boats were absent from the area, and for days when dive boats were present, conducting shark provisioning. Vertical activity levels varied between day and night, and with the presence of boats. In natural conditions (no boats present), sharks remained at more constant depths during the day, while at night animals continuously moved up and down the water column, showing that whitetip reef sharks are nocturnally active. When boats were present, however, there were also long periods of vertical activity during the day. If resting periods during the day are important for energy budgets, then shark provisioning may affect their health. So, if this behaviour alteration occurs frequently, e.g., daily, this has the potential to have significant negative effects on the animals’ metabolic rates, net energy gain and overall health, reproduction and fitness.

Item Type:	Refereed Article
Keywords:	Triaenodon obesus, ecotourism, shark feeds, depth use, disturbance, behavioural response, provisioning, sharks
Research Division:	Agricultural and Veterinary Sciences
Research Group:	Fisheries Sciences
Research Field:	Fisheries Management
Objective Division:	Environment
Objective Group:	Ecosystem Assessment and Management
Objective Field:	Ecosystem Assessment and Management of Coastal and Estuarine Environments
Author:	Barnett, A (Dr Adam Barnett)
ID Code:	76324
Year Published:	2011
Web of Science® Times Cited:	58
Deposited By:	Sustainable Marine Research Collaboration
Deposited On:	2012-03-05
Last Modified:	2012-10-11
Downloads:	24 View Download Statistics