Latest Scientific Research Publications

Impact of shark-feeding tourism on surrounding fish populations off Moorea Islan
Matthias Vignon, Pierre Sasal, Ryan L. Johnson and Renéé Galzin (in press) Impact of shark-feeding tourism on surrounding fish populations off Moorea Island (French Polynesia). Journal of Marine Freshwater research.
Coastal swimming patterns of white sharks at Mossel Bay
Johnson, R., Bester, M.N., Dudley, S.F.J., Oosthuizen, W.H., Meÿer, M.A., Hancke, S. & Gennari, E. (2009) Coastal swimming patterns of white sharks (Carcharodon carcharias) at Mossel Bay, South Africa. Environmental Biology of Fishes, 85(3):189-200.
Concordance of genetic and fin photo identification in the great white shark of Mossel Bay
Gubili, C., Johnson, R., Gennari, E., Oosthuizen, w.H., Kotze, P.G.H., Meÿer, M.A., Sims, D.W., Jones, C.S. & Noble, L.R. (2009) Concordance of genetic and fin photo identification in the great white shark, Carcharodon carcharias, of Mossel Bay, South Africa. Marine Biology Published on-line first.
Encounters between white sharks and Cape fur seals in a shallow channel
R. Johnson, T. Keswick, M.N. Bester and W.H. Oosthuizen (2008) Encounters between white sharks and Cape fur seals in a shallow channel. Journal of the Marine Biological Association - Biodiversity Records, Published on-line.
White shark abundance: not a causative factor in numbers of shark bite incidents
Kock A., Johnson, R.L., Bester M.N., Compagno L., Cliff G., Dudley S., Gennari E., Griffiths C.L., Kotze D., Laroche K., Meyer M.A., Oosthuizen W.H. and Swanson, S. (2006). White shark abundance: not a causative factor in numbers of shark bite incidents. In: Nel D.C. & Peschak T.P. (eds.): Finding a balance: white shark conservation and recreational safety in the inshore waters of Cape Town, South Africa - proceedings of a specialist workshop. WWF South Africa Report Series - 2006/Marine/001: 1-19.

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Contact Marine Explorer Ryan Johnson

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Great White Sharks bite strength

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About the Project

In 2005 I began to investigate the power of a white sharks bite using a bite force meter custom designed by National Geographic, and kindly donated to me by Dr. Brady Barr. Brady had been using it for a series to measure the strongest bites in nature, however, I wanted to study how dexterous a great whites mouth (and bite) is. I fully believe that the survival of many humans following been bitten by a great white is due to it giving a ‘comparatively’ light, investigatory type bite. The bite meter confirmed this theory, with sharks been able to modify their bite force by a factor of five!