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The Mistaken Identity Hypothesis (MIH) interprets shark bites on surfers, swimmers and snorkelers as 'mistakes' stemming primarily from similarities in the visual appearance of ocean users and the sharks typical prey. MIH is now widely accepted as fact by the general public and some sections of the scientific community despite remaining unproven. This hypothesis assumes that 'mistaken' shark bites on humans result primarily from confusing visual cues and ignores the important role of other senses (e.g. hearing) in discriminating potential prey. A far simpler 'natural exploration' hypothesis can reasonably explain not only shark bites that have been characterized as 'mistaken identity' events but also those that cannot be reasonably explained by MIH (e.g. shark bites that occur in very clear water). Simply stated, sharks don't make 'mistakes' but instead continually explore their environments and routinely investigate novel objects as potential prey by biting them. [ABSTRACT FROM AUTHOR]

Although many animal species demonstrate individual personalities, studying these traits in wild sharks has proven challenging. Past research focused mainly on captive or juvenile sharks. Our ethological study of 31 wild adult bull sharks (Carcharhinus leucas) utilized an artificial provisioning site, amassing 2813 observations over 651 dives from October 2015 to January 2018 (27 months). Behavioural traits, including boldness-shyness and aggressiveness-placidity, were assessed using an ad hoc ethogram and an influencing factors table. This innovative approach not only allowed us to characterize individual shark behaviours but also to quantify their changes over time. Our findings suggest that adult bull sharks likely possess distinct personalities, spanning from extreme shyness to pronounced boldness, with varying levels of plasticity among individuals. Further exploration of shark personalities holds promise for advancing our comprehension of human–shark interactions and refining the management of potential aggressive behaviours exhibited by large shark species toward humans. [ABSTRACT FROM AUTHOR]

In this review of the behavioural patterns of chondrichthyan fishes, we have strived to produce a comprehensive catalogue of events and states and develop standardized terminology. Hence, actions that are slightly different, will be pooled under inclusive titles. Those used by different investigators are included in quotations within the textual descriptions of the motor patterns. This standardized ethogram will ideally lead to an increase in inter-observer reliability, giving researchers more confidence when reading colleagues' papers that report behaviours that appear similar to theirs despite being described for different species. The descriptions are presented under the following categories: (1) maintenance (2) courtship (3) filter feeding (4) scavenging (5) predation (6) sociality (7) aggression and (8) defence. The many actions are illustrated by line drawings and photographs in composite figures with an attempt to provide an example of each action for a chimaera, shark, and ray. The diversity of patterns is evident from this ethogram, consistent with observation that the brain-to-body mass ratios of cartilaginous fishes are greater than a third of the bird species and greater than those for some mammalian species. The major impetus for assembling this ethogram is to demonstrate the diversity of behaviours exhibited by members of the Chondrichthyes and to dispel the apocryphal belief that members of this taxon are 'simple feeding machines'. [ABSTRACT FROM AUTHOR]

Shark-based ecotourism has been recently expanding around the world. Provisioning sharks, however, is not without risk and accidental bites on humans are regularly reported. Such events may jeopardise the shark ecotourism industry and local economies. Through a case study from French Polynesia, I investigated whether changes in feeding practices of lemon sharks between the early 1990s and 2013 are related to recent accidental bites of divers. Hand-feeding, ‘smelling’ and surface feeding facilitated the development of agonistic behaviour in sharks, which resulted in accidental bites. The level of interaction between sharks and humans appears to be the most important driver for analysing bite-risk. This paper presents the very first framework for risk-analysis and will allow managers to better manage the risk associated with current practices in shark-feeding around the world. The paper also provides technical guidelines for the design of adequate legal frameworks that will support any sustainable shark feeding operation. [ABSTRACT FROM AUTHOR]

Selective removal of problem individuals following shark bite incidents would be consistent with current management practices for terrestrial predators, and would be more effective and more environmentally responsible than current mass-culling programs. In parallel, and in addition to traditional forensics analysis, we recommend the routine collection of shark DNA from wounds or devices following shark bite incidents in order to genetically identify the individual responsible. This approach would require creating an extensive database of shark identities in high-risk areas against which to compare DNA forensically recovered from shark bite incidents. At a local and regional scale, we propose utilizing existing shark tagging programs and artificial shark aggregation sites to collect DNA, behavioural and morphological data for the database, and to facilitate removal of problem individuals. In several places around the world, selective removal of problem individuals would not be significantly more expensive and definitely less environmentally-destructive than traditional approaches and would also help reconcile people and sharks by underlining individuality in shark behaviour. • Indirect proofs suggest that fatal bites on humans are linked to problem individuals rather than environmental factors or shark densities. • Instead of unselective mass fishing campaigns, we recommend the selective removal of sharks that have already perpetrated an attack. • Problem individuals would be identified through a two-fold genetic approach. • On one side, an individual DNA profile (fingerprinting) of the shark would be obtained from the victims' wounds or bitten devices. • On another side, extensive databases would allow to gather individual DNA profiles, visual cues or tag identities to identify and remove the sharks. [ABSTRACT FROM AUTHOR]