About the Authors

Alison V. Towner

Affiliations Dyer Island Conservation Trust, Great White House, Kleinbaai, Gansbaai, South Africa, Department of Zoology, University of Cape Town, Rondebosch, South Africa

Michelle A. Wcisel

Affiliations Dyer Island Conservation Trust, Great White House, Kleinbaai, Gansbaai, South Africa, Department of Zoology, University of Cape Town, Rondebosch, South Africa

Ryan R. Reisinger

Affiliation Mammal Research Institute, Department of Zoology and Entomology, University of Pretoria, Hatfield, South Africa

David Edwards

Affiliation Dyer Island Conservation Trust, Great White House, Kleinbaai, Gansbaai, South Africa

Oliver J. D. Jewell

oliverjewell@gmail.com

Affiliations Dyer Island Conservation Trust, Great White House, Kleinbaai, Gansbaai, South Africa, Mammal Research Institute, Department of Zoology and Entomology, University of Pretoria, Hatfield, South Africa

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

Wrote the paper: OJ MW AT RR DE. Initiated the project: AT MW OJ. Collected fin ID photographs: AT OJ MW. Determined methodology for processing fin IDs: MW. Cataloged and cropped photos in Picasa: MW DE OJ AT. Processed fin IDs in DARWIN: DE MW. Ran MARK analysis: RR. Produced figures: DE RR. Wrote the paper: OJ MW AT RR DE.