Effects of provisioning ecotourism activity on the behaviour of white sharks Carcharodon carcharias

Abstract

Ecotourism operations which provide food to large predators have the potential to negatively affect their target species, by conditioning them to associate humans with food, or by generally altering their behavioural patterns. This latter effect could have potentially detrimental consequences for the ecosystem inhabited by the predator, because any behavioural changes could affect the species with which they interact. We present the results of an experimental study conducted from June to October 2004, which examined the effects of provisioning ecotourism on the behaviour of white sharks around a seal colony on a small island in South Africa. Although ecotourism activity had an effect on the behaviour of some sharks, this was relatively minor, and the majority of sharks showed little interest in the food rewards on offer. It is unlikely that conditioning would occur from the amount of ecotourism activity tested, because even those sharks identified supplying most of the data presented here (which may be more strongly predisposed towards conditioning, as their persistence around the boat is what allowed them to be identified) showed a nearly ubiquitous trend of decreasing response with time. Furthermore, even the sharks frequently acquiring food rewards typically stopped responding after several interactions. Consequently, moderate levels of ecotourism probably have only a minor impact on the behaviour of white sharks, and are therefore unlikely to create behavioural effects at the ecosystem level.

Reef-use and residency patterns of a baited population of silky sharks, Carcharhinus falciformis, in the Red Sea

“…1) and procedures were similar to previous studies that avoided hooking individuals (e.g. Laroche et al 2007). The transmitters (tags) were attached via a short wire tether to a small plastic umbrella dart (Domeier et al 2005), placed adjacent to the base of the dorsal fin.…”

Hand feeding can periodically fuel a major portion of bull shark energy requirements at a provisioning site in Fiji

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Diver ecotourism and disturbance to reef fish spawning aggregations: It is better to be disturbed than to be dead

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