CONFLICTS BETWEEN LARGE MARINE PREDATORS AND HUMANS: THE GENESIS AND MANAGEMENT OF PROBLEM INDIVIDUALS – ETHO-PREDATOR

We have chosen two taxa that are potentially «problematic« (with an anthropocentric approach to which we do not necessarily subscribe) in relation to people: the shark and the killer whale. Our first aim is to demonstrate the existence of personalities in these two taxa, by characterizing divergent individual behaviors that are constant over time and across situations, and by demonstrating the heritability of these behaviors. The shark component is taking place in Fiji (Central West Pacific), where the behavior of bull sharks Carcharhinus leucas in artificial feeding situations is being studied, at the same time as biopsies are being taken for genetic analysis. The Orcinus orca component takes place in the Crozet archipelago (Sub-Antarctic), where the differential behavior of the animals is detected in the context of their depredation on industrial toothfish fishing. The animals are also biopsied. The creation of pedigrees for both taxa should enable us to test the hypothesis of intergenerational heritability of personality traits such as boldness and risk-taking.

The issue of the existence of personalities in large marine vertebrates is almost unexplored to date and ETHO-PREDATOR is probably the first major international project to address this issue at this scale, in close connection with evolutionary and conservation biology. Beyond this central subject, the scientific issues at stake include the genetic mechanisms on which these personalities are based (at least their exploration) and the subject of conflicts with humans. These are very transversal themes that will have an undeniable scientific echo.

Concerning shark risk management, a better understanding of the genesis of 'problem Inndividuals' (PIs) (responsible for fatal bites on humans with a food motivation) will be a major asset in improving management approaches. A major consequence could be the abandonment of non-selective culling campaigns, based on the (unproven) density-dependence hypothesis, in favor of selective removal of PIs. In this respect, this ANR is expected to provide insights into the technical choices (and communication strategy) to be made in a shark risk management project that will start in the Caribbean concurrently with ETHO-PREDATOR (see Tab. 2 - ONE-SHARK 2021-2023 'proof of concept' project). On a larger scale, these advances will be of interest to other decision-makers and managers who have to deal with shark risk, whether in the Indian Ocean (Reunion and South Africa) or the Eastern Pacific Ocean (Australia and New Caledonia). The US network of managers of terrestrial predator attacks on humans (http://wildlifeattack.com/) has shown great interest in disseminating technical knowledge in link with the marine realm, including both sharks and killer whales. For killer whales, and to a greater extent, for all marine mammal species involved in the depredation conflict with fisheries, the project is expected to provide crucial information on the short- and long-term risks of these interactions on populations. Specifically, by highlighting the existence of PIs, and demonstrating that bold individuals towards fisheries are the ones most exposed to lethal retaliation practices by fishers, the study will shine a light on the threats and the selection pressures currently faced by many other cetacean populations depredating on fishery catches worldwide. The long–term Crozet Killer whale dataset and monitoring as well as observations opportunities of individuals involved both in fishery interactions and natural predation behaviours provide to our knowledge an opportunity without equivalent to address this question.

By aggregating very complementary and internationally recognized competences, in particular through the members of the Monitoring committee, this project should lead to several A rank articles (preferably in open access journals) touching on ethology, genetics, evolutionary and conservation biology, socio-anthropology, without forgetting more applied subjects inherent to risk management. Several students will be at the heart of the project and will gain experience and skills that will be very important for their careers.

Conflicts between humans and large marine predators are increasing around the world, often resulting in excess mortality of animals without satisfactory results in terms of effectiveness (to reduce risk) and respect for conservation issues (regarding threatened species). The risk management response in aquatic environments often consists of non-selective removal of animals, such as for sharks after human fatalities, based on the assumption that the risk is correlated with their density. In our study, we propose to test an alternative hypothesis based on the existence of problem individuals (PIs) -demonstrated in terrestrial environments- in two species (a toothed cetacean and a shark) in which parental guidance diverges significantly. This hypothesis of PIs is based on the existence of divergent temperaments and personality traits such as boldness-shyness (management of novelty) and risk-taking-avoidance (management of danger) which would be transmitted from one generation to another. With an ethological approach, the existence of these behavioural traits will be tested on killer whales in Antarctica and on two behaviours: i) the hunting technique of voluntary stranding on beaches to predate elephant seal juveniles and ii) the depredation of hooked fish in the context of commercial longline fisheries. In parallel, two populations of bull sharks will be studied in Fiji in the framework of observation dives based on artificial feeding; the behaviours studied will be i) the attitude towards artificial food (novelty), ii) towards divers (danger) and between conspecifics (sociability and agressiveness). The observations will take place over two years in order to be able to i) discriminate individual divergent behaviours (Work package - WP1) and show ii) that they are consistant in time and iii) according to various situations (WP2). This fieldwork will be accompanied by DNA sampling of monitored animals. WP3 will consist in demonstrating the heritability of personalities between generations in the bull shark (RAdseq analyses on n=60 individuals) and in killer whales (pedigree with n=30 individuals); we will also try to explore the molecular mechanisms on which this heritability could rely. WP4 will synthesize the results concerning the genesis of PIs (influence of genetics vs learning processes) within the two taxa and will conduct a socio-anthropological study on the perception by the various stakeholders of the human-large marine predator conflicts. These approaches should allow us to better understand the evolutional and survival issues for both taxa (fundamental science), but also to address societal issues (applied science), in terms of proposing improved risk and conservation management. The research consortium will be composed of four institutional partners, namely CRIOBE (EPHE-CNRS), CEBC (CNRS-ULR), MARBEC (IRD) and SENS (IRD), providing three research directors, three research fellows and two PhD students (not funded by ANR - sex-ratio F 33%) directly involved in the WPs. The project will be co-coordinated by two of the senior researchers with solid experience in managing international scientific projects. They will be supported by an external monitoring committee composed of four senior researchers with international expertise in shark ecology (Univ. of Hawaii), vertebrate ethology (Univ. Quebec in Montreal), genetics (CRIOBE) and human-wildlife conflict management (Norwegian Institute for Nature Research). The project plans to recruit two PhD students to work respectively on the collection of ethological data on killer whales in Antarctica and sharks in Fiji, an 18-month post-doc to support the genetic component and five Master2 students. A grant of 750 k€ is requested, 46% of which is allocated to the recruitment of students, 33% to the collection of data in Antarctica and Fiji and the rest (9% excluding management fees) essentially for genetic analyses, anthropological study, communication and publication costs.