Global shark attack hotspots: Identifying underlying factors behind increased unprovoked shark bite incidence

Abstract Unprovoked shark bite remains a rare, unlikely occurrence; however, shark bite incidence is increasing world-wide. In an effort to understand why shark bite incidence is increasing, we examine recent trends in unprovoked shark bite statistics and other media from the six global shark bite “hotspots”, the United States, South Africa, Australia, Brazil, Reunion Island and the Bahamas, and review recent literature that identifies potential causative factors that may contribute to rising shark bite incidence. Increases in shark bite incidence are likely attributable to rises in human population, as well as other causative factors, including habitat destruction/modification, water quality, climate change and anomalous weather patterns and the distribution/abundance of prey. Our analysis shows that increases are likely the result of a set of conditions that disrupts the natural balance of an area at a local or regional level and increases the probability of shark-human interaction. We also present recommendations for future management of shark-human interaction.

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