343 research outputs found

    Measuring the effect of whalewatching boats on minke whale behavioural budget using a multivariate hidden Markov model

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    Human disturbances of wildlife, such as tourism, can alter the activities of targeted individuals. Repeated behavioural disruptions can have long-term consequences on individual's vital rates. To manage these sub-lethal impacts, we need to understand how activity disruptions can influence variation in individual's vital rates. This study informs the mechanistic links between whalewatching boat exposure and behavioural variation and vital rates for Mysticetes. We compared Minke whale Balaenoptera acutorostrata behaviour on a feeding ground in the presence and absence of whalewatching boats in Iceland, using individual focal follows. Activity states were inferred from movement metric data and multi-state models were used to estimate the relative proportion of different activity states. Spatially explicit mark-recapture models were used to estimate the seasonal exposure rate of individual whales to whalewatching activities. Whalewatching interactions disrupted the foraging behaviour of Minke whales, causing a decrease in proportion of time whales spent foraging. The cumulative exposure was sufficiently large to cause changes in the animal's seasonal behavioural budget. Minke whales are capital breeders, so a decrease in foraging success on feeding grounds due to whalewatching could lead to a decrease in energy available for lactation on breeding grounds, which could have negative effects on calf survival

    Parallels of human language in the behavior of bottlenose dolphins

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    A short review of similarities between dolphins and humans with the help of quantitative linguistics and information theory

    Understanding the ecological effects of whale-watching on cetaceans

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    Whale-watching is a potentially sustainable use of cetaceans and an economically viable alternative to whaling and has become a major contributor to the tourism sector of many countries (Hoyt, 2001; O’Connor et al., 2009). Whale-watching also has the potential to improve people's attitude toward the marine environment, and promote public awareness and support for the conservation issues that targeted species face (Duffus & Dearden, 1993). However, whale-watching can put cetaceans at risk of being harassed and injured by an unknown number of unpredictable impacts which can pose a risk to the viability of the targeted population, as well as the whale-watching industry itself. Reported effects of human disturbance on ceta-ceans cover a range of taxa, including many odontocete species and several species of mysticetes (see Chapter 16). Even though many studies have shown that whale-watching can cause both short- (Nowacek et al., 2001; Williams et al., 2002b; Lusseau, 2003a; Christiansen et al., 2010) and long-term negative effects on cetaceans (Bejder et al., 2006; Fortuna, 2006; Lusseau et al., 2006b), few studies have focused on explaining the underlying cause, or ecological and evolutionary mechanisms for these effects (Frid & Dill, 2002). Understanding how human interactions affect wildlife is crucial for the sustainable management of any nature-based tourism activity. This chapter address-es the ecological foundations of whale-watching disturbance on cetaceans. It gives an overview of the documented impacts of whale-watching on cetaceans and compares this to observations of natural predation. It then tries to explain how whale-watching is perceived by the animals to understand the underlying ecological and evolutionary basis for these responses. It goes on to discuss different factors that are likely to influence the response of animals to whale-watching. We then discuss the long-term effects of whale-watching on cetaceans by following the mechanistic link between behavioural effects and vital rates within an energetic framework. Ecological and biological constraints to the ability of cetaceans to cope with disturbance are discussed as well as their implication for long-term vital rates

    Managing whale-watching as a non-lethal consumptive activity

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    Marine tourism is a new frontier of late-capitalist transformation, generating more global revenue than aquaculture and fisheries combined. This transformation created whale-watching, a commercial tourism form that, despite recent critiques, has been accepted as non-consumptive activity. This paper uses four academic discourses to critique whale-watching as a form of capitalist exploitation: (1) commercial whale-watching and global capitalist transformation, (2) global capitalist politics and the promoted belief that whale-watching is non-consumptive, (3) the inherent contradictions of non-consumptive capitalist exploitation, and (4) whale-watching as a common-pool resource. These discourses lead us to critique whale-watching practices in relation to the common capitalist sequence of resource diversification, exploitation, depletion and collapse. Using specific impact studies, we conclude that a sustainability paradigm shift is required, whereby whale-watching (and other forms of wildlife tourism) is recognized as a form of non-lethal consumptive exploitation, understood in terms of sub-lethal anthropogenic stress and energetic impacts. We argue the need for a paradigm shift in the regulation and management of commercial whale-watching, and present the case for a unified, international framework for managing the negative externalities of whale-watching. The relevance of the issues raised about neoliberal policy-making extends beyond whale-watching to all forms of wildlife and nature-based tourism

    Clones in Graphs

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    Finding structural similarities in graph data, like social networks, is a far-ranging task in data mining and knowledge discovery. A (conceptually) simple reduction would be to compute the automorphism group of a graph. However, this approach is ineffective in data mining since real world data does not exhibit enough structural regularity. Here we step in with a novel approach based on mappings that preserve the maximal cliques. For this we exploit the well known correspondence between bipartite graphs and the data structure formal context (G,M,I)(G,M,I) from Formal Concept Analysis. From there we utilize the notion of clone items. The investigation of these is still an open problem to which we add new insights with this work. Furthermore, we produce a substantial experimental investigation of real world data. We conclude with demonstrating the generalization of clone items to permutations.Comment: 11 pages, 2 figures, 1 tabl

    Effects of vessel traffic on relative abundance and behaviour of cetaceans : the case of the bottlenose dolphins in the Archipelago de La Maddalena, north-western Mediterranean sea

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    Acknowledgements This study was part of the Tursiops Project of the Dolphin Research Centre of Caprera, La Maddalena. Financial and logistical support was provided by the Centro Turistico Studentesco (CTS) and by the National Park of the Archipelago de La Maddalena. We thank the Natural Reserve of Bocche di Bonifacio for the support provided during data collection. The authors thank the numerous volunteers of the Caprera Dolphin Research Centre and especially Marco Ferraro, Mirko Ugo, Angela Pira and Maurizio Piras whose assistance during field observation and skills as a boat driver were invaluable.Peer reviewedPostprin

    Influence of body condition on the population dynamics of Atlantic salmon with consideration of the potential impact of sea lice

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    We thank Marine Scotland Science (MSS) for providing the studentship for this work. We are grateful to Alexander G Murray from MSS Aberdeen for providing data for model parameterization. We also want to thank Gordon Smith and Ian Simpson from MSS Montrose, as well as the owner and staff of the net fishery at North Esk for enabling data collection. We thank Peerage of Science and two anonymous referees for constructive comments and critique points which considerably improved earlier drafts.Peer reviewedPublisher PD

    The effects of graded levels of calorie restriction : VIII. impact of short term calorie and protein restriction on basal metabolic rate in the C57BL/6 mouse

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    We are grateful to the animal house staff for looking after the animals. The work was supported by the UK Biotechnology and Biological Sciences Research Council BBSRC (grants BB/G009953/1 and BB/J020028/1) to JRS and SEM. DD was supported by a studentship from the Centre for Genome Enabled Biology and Medicine, Aberdeen, UK, and CG was supported by a BBSRC EastBio studentship. Joint meetings were funded by a BBSRC China partnering award (BB/JO20028/1).Peer reviewedPublisher PD
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