Marine mammal behavior: a review of conservation implications

This is the author accepted manuscript. The final version is available from Frontiers Media via the DOI in this record.The three orders which comprise the extant marine mammals exhibit a wide range of behaviors, varying social structures and differences in social information use. Human impacts on marine mammals and their environments are ubiquitous; from chemical and noise pollution, to marine debris, prey depletion and ocean acidification. As a result, no marine mammal populations remain entirely unaffected by human activities. Conservation may be hindered by an inadequate understanding of the behavioral ecology of some of these species. As a result of social structure, social information use, culture and even behavioral syndromes, marine mammal social groups and populations can be behaviorally heterogeneous. As a result responses to conservation initiatives, or exploitation, may be complex to predict. Previous commentators have highlighted the importance of incorporating behavioral data into conservation management and we review these considerations in light of the emerging science in this field for marine mammals. Since behavioral canalization may lead to vulnerability, whereas behavioral plasticity may provide opportunity for resilience, we argue that for many of these socially complex, cognitive species understanding their behavioral ecology, capacity for social learning and individual behavioral variation, may be a central tenant for their successful conservation.The lead author’s research is funded by WDC (Whale and Dolphin Conservation)

Tail walking in a bottlenose dolphin community : the rise and fall of an arbitrary cultural 'fad'

M.B. was supported by multiple grants from Whale & Dolphin Conservation (WDC).Social learning of adaptive behaviour is widespread in animal populations, but the spread of arbitrary behaviours is less common. In this paper, we describe the rise and fall of a behaviour called tail walking, where a dolphin forces the majority of its body vertically out of the water and maintains the position by vigourously pumping its tail, in a community of Indo-Pacific bottlenose dolphins (Tursiops aduncus). The behaviour was introduced into the wild following the rehabilitation of a wild female individual, Billie, who was temporarily co-housed with trained dolphins in a dolphinarium. This individual was sighted performing the behaviour seven years after her 1988 release, as was one other female dolphin named Wave. Initial production of the behaviour was rare, but following Billie's death two decades after her release, Wave began producing the behaviour at much higher rates, and several other dolphins in the community were subsequently sighted performing the behaviour. Social learning is the most likely mechanism for the introduction and spread of this unusual behaviour, which has no known adaptive function. These observations demonstrate the potential strength of the capacity for spontaneous imitation in bottlenose dolphins, and help explain the origin and spread of foraging specializations observed in multiple populations of this genus.PostprintPeer reviewe

Animal cultures matter for conservation

This is the author accepted manuscript. The final version is available from AAAS via the DOI in this record.No abstrac

Rate of exposure of a sentinel species, invasive American mink (Neovison vison) in Scotland, to anticoagulant rodenticides

Anticoagulant rodenticides (ARs) are highly toxic compounds that are exclusively used for the control of rodent pests. Despite their defined use, they are nonetheless found in a large number of non-target species indicating widespread penetration of wildlife. Attempts to quantify the scale of problem are complicated by non-random sampling of individuals tested for AR contamination. The American mink (Neovison vison) is a wide ranging, non-native, generalist predator that is subject to wide scale control efforts in the UK. Exposure to eight ARs was determined in 99 mink trapped in NE Scotland, most of which were of known age. A high percentage (79%) of the animals had detectable residues of at least one AR, and more than 50% of the positive animals had two or more ARs. The most frequently detected compound was bromadiolone (75% of all animals tested), followed by difenacoum (53% of all mink), coumatetralyl (22%) and brodifacoum (9%). The probability of mink exposure to ARs increased by 4.5% per month of life, and was 1.7 times higher for mink caught in areas with a high, as opposed to a low, density of farms. The number of AR compounds acquired also increased with age and with farm density. No evidence was found for sexual differences in the concentration and number of ARs. The wide niche and dietary overlap of mink with several native carnivore species, and the fact that American mink are culled for conservation throughout Europe, suggest that this species may act as a sentinel species, and the application of these data to other native carnivores is discussed

Animal cultures matter for conservation

Understanding the rich social lives of animals benefits international conservation efforts.PostprintPeer reviewe

Incorporating non-equilibrium dynamics into demographic history inferences of a migratory marine species

ELC was supported while writing this paper by a EU Horizon 2020 Marie Slodowska Curie Fellowship, project BEHAVIOUR-CONNECT, by a Newton Fellowship from the Royal Society of London and Bayesian statistical training was supported by National Science Foundation (award DEB- 1145200). Laboratory analyses conducted by ELC were funded by a small grant from the British Ecological Society 5076 / 6118 and Bayesian analysis was supported by training from the National Science Foundation under Grant No. DEB-1145200. OEG was supported by the Marine Alliance for Science and Technology for Scotland (MASTS) funded by the Scottish Founding Council (grant reference HR09011). Genetic data from the South African right whale samples were generated by MB and PJP with the support of UC Berkeley, University of Stockholm and University of Groningen. Computational Biology analyses were supported by the University of St Andrews Bioinformatics Unit which is funded by a Wellcome Trust ISSF award.Understanding how dispersal and gene flow link geographically separated populations over evolutionary history is challenging, particularly in migratory marine species. In southern right whales (SRWs, Eubalaena australis), patterns of genetic diversity are likely influenced by the glacial climate cycle and recent history of whaling. Here we use a dataset of mitochondrial DNA (mtDNA) sequences (n=1,327) and nuclear markers (17 microsatellite loci, n=222) from major wintering grounds to investigate circumpolar population structure, historical demography, and effective population size. Analyses of nuclear genetic variation identify two population clusters that correspond to the South Atlantic and Indo-Pacific ocean basins that have similar effective breeder estimates. In contrast, all wintering grounds show significant differentiation for mtDNA, but no sex-biased dispersal was detected using the microsatellite genotypes. An approximate Bayesian computation (ABC) approach with microsatellite markers compared scenarios with gene flow through time, or isolation and secondary contact between ocean basins, while modeling declines in abundance linked to whaling. Secondary-contact scenarios yield the highest posterior probabilities, implying that populations in different ocean basins were largely isolated and came into secondary contact within the last 25,000 years, but the role of whaling in changes in genetic diversity and gene flow over recent generations could not be resolved. We hypothesis that these findings are driven by factors that promote isolation, such as female philopatry, and factors that could promote dispersal, such oceanographic changes. These findings highlight the application of ABC approaches to infer connectivity in mobile species with complex population histories and currently low levels of differentiation.PostprintPeer reviewe

The significance of non-human culture for the conservation of cetaceans and other vertebrates

The central proposition of this thesis is that non-human cultural transmission can interface with population dynamics to generate patterns and processes which can cause population level effects and thus inform conservation science, policy and practice. Culture can provide insights for both how conservation is conducted and what managers should be aiming to conserve (the ‘unit to conserve’). In this research, available evidence was gathered and a wide collaboration with experts in this field was established. This enabled the development of a conceptual framework to help guide researchers and practitioners towards ‘future-proofing’ populations by conserving both cultural variation and the capacity for innovation and social learning to maximize the resilience of vulnerable populations. To illuminate some of the underlying processes, theoretical models were then constructed to investigate the dual dynamics of cultural transmission and population dynamics. Here it is shown that social learning can generate transient dynamics which may inform the timing of some conservation interventions. It is also demonstrated that under certain parameter regimes social learning can bring about cultural bistability, cultural hysteresis, or cultural exclusion. Further, it is shown how in a density dependent system, cultural transmission could generate chaos. These findings are considered within the context of conservation and policy. It is concluded that given the complexity of the coupled processes of population dynamics and cultural transmission - and the practical challenges associated with collecting fine scale data on how culture may influence vital rates - that conservation policy makers and practitioners should aim to conserve cultural diversity, within and between populations, as an essential source of adaptive behaviour