Wildlife Research Wildlife Research Society
Ecology, management and conservation in natural and modified habitats

An assessment of the audibility of sound from human transport by breeding Weddell seals (Leptonychotes weddellii)

Tamara D. van Polanen Petel A D , John M. Terhune B , Mark A. Hindell A and Melissa A. Giese C
+ Author Affiliations
- Author Affiliations

A School of Zoology, University of Tasmania, PO Box 252-05, Tas. 7001, Australia.

B Centre for Coastal Studies and Aquaculture, University of New Brunswick, PO Box 5050, Saint John, New Brunswick, E2L 4L5, Canada.

C Human Impacts Research Program, Australian Antarctic Division, Channel Highway, Tas. 7050, Australia.

D Corresponding author. Email: tdvan@postoffice.utas.edu.au

Wildlife Research 33(4) 275-291 https://doi.org/10.1071/WR05001
Submitted: 5 January 2005  Accepted: 3 February 2006   Published: 27 June 2006


Anthropogenic noise generated through travel in the Antarctic has the potential to affect the region’s wildlife. Weddell seals (Leptonychotes weddellii) in particular can be exposed to anthropogenic noise because they live under, and breed on, the fast ice on which humans travel. To investigate the potential effects of anthropogenic noise on Weddell seals we developed sound profiles for pedestrian travel, over-snow vehicles, aircraft and watercraft operating at various distances and altitudes from breeding seals. The received 1/3-octave noise levels were then related to an assumed detection threshold for the Weddell seal. We found that most noise levels generated by the pedestrian, quad (4-wheeled, all-terrain vehicle) and Hagglunds (tracked, all-terrain vehicle) were commonly categorised in the inaudible and barely audible range of detection (both in-air and underwater), while noise levels generated by the helicopter, Twin Otter aircraft and Zodiac boat were categorised more commonly in the barely audible and clearly audible range. Experimental underwater recordings of vocal behaviour of Weddell seals exposed to continuous low-amplitude over-snow vehicle noise (i.e. Hagglund operation) were also made. Weddell seals underwater did not alter individual call types in response to low-level Hagglunds noise, but they did decrease their calling rate.


We thank Sarah Brown, Kate Bodley and Marjolein van Polanen Petel and other members of the 54th and 55th ANARE expeditions to Casey Station and Davis Station. We also thank the Australian Antarctic Division for providing the geographic data for the maps used (Fig. 1). The study was conducted with permission from the Australian Antarctic Animal Ethics Committee, Australian Antarctic Division and the Animal Ethics Committee of the University of Tasmania. The Australian Antarctic Division, Sea World Research and Rescue Foundation, Natural Sciences and Engineering Research Council (NSERC) of Canada and the University of Tasmania supported fieldwork and data analysis. Additional funding was given to TDvPP from the Australian Government through an Australian Postgraduate Award and from the Sustainable Tourism Cooperative Research Centre.


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