46 research outputs found

    First GPS-tracking of Cory’s shearwater in the Mediterranean Sea.

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    The behaviour and the ecology of seabirds such as albatrosses, petrels and shearwaters have been subject of numerous studies, often employing the most recent technologies to track birds during their foraging trips. Until now, however, big oceanic species have been preferred for these studies because of the dimensions and weight of the devices. New light GPS loggers (<9g) were used to track foraging trips of a medium-sized species, the Cory’s shearwater, for the first time in the Mediterranean Sea. The tracks obtained in our study showed that Mediterranean Cory’s shearwaters alternatively used one of two different fishing areas. Various explanations could account for this difference; one of these could be that the two directions have a different relevance for the birds being for chick- and self-provisioning. This study provides new hypotheses concerning the behaviour of Cory’s shearwaters in the Mediterranean Sea, which is a different environment respect to previously studied oceans

    Retail ring-fencing of banks and its implications

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    Financial stability remains a key theme globally in view of the Euro zone debt crisis. The latest strategy by Germany and France is to ring-fence the crisis among the PIIGS countries (Portugal, Greece, Ireland, Italy and Spain). In the United Kingdom, the big four major banks have all responded to the Independent Commission of Bankings interim report key recommendation: ring-fencing retail operations into a separate subsidiary of any bank that wishes to operate in the United Kingdom. The report has clearly discussed the advantages and disadvantages of various types of subsidiarisation. Retail ring-fencing is considered a compromise as full subsidiarisation is too costly and operational subsidiarisation is too minimal. The Independent Commission of Banking published its final report on 12 September 2011. They recommended ring-fencing retail banking and a 10 per cent equity baseline. This article focuses on structural reforms of UK banks. It aims to address the question of financial stability from a wider European perspective. The first question is whether cross-border retail banking in the European Economic Area (EEA) is best served by branches or subsidiaries? The second question concerns the legality of setting up subsidiaries in the European Union (EU). Although there are no legal problems for UK-based banks setting up subsidiaries for their retail activities, there might be a legal hurdle for requiring foreign banks setting up subsidiaries in the United Kingdom. The third question concerns EU cross-border banking regulation and supervision. Are the passporting system and the home country supervisory approach still applicable in this post-financial crisis era? Many factors influence the choice of setting up branches or subsidiaries. However, the general position is that branches are more suited for wholesale/investment activities because of ease of funds transfer. Subsidiaries are more suitable for retail banking because of the limited liability principle and extensive local network. Effective cross-border banking must be accompanied by effective supervision and resolution regimes. The passporting concept under EU law and home country dominance are somewhat dated post-financial crisis. Host country control should play a dominant part in financial regulation, especially in the light of the importance of subsidiaries and the limited liability principle associated with them. The Icelandic bank crisis and collapse of Lehman Brothers International Europe illustrate the importance of host country control. Finally, the author argues that requiring banks to hold its retail activities in the form of subsidiaries in another European country is necessary to achieve financial stability. © 2012 Macmillan Publishers Ltd

    Consistency of Leadership in Shoals of Mosquitofish (Gambusia holbrooki) in Novel and in Familiar Environments

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    In social animal groups, an individual's spatial position is a major determinant of both predation risk and foraging rewards. Additionally, the occupation of positions in the front of moving groups is generally assumed to correlate with the initiation of group movements. However, whether some individuals are predisposed to consistently occupy certain positions and, in some instances, to consistently lead groups over time is as yet unresolved in many species. Using the mosquitofish (Gambusia holbrooki), we examined the consistency of individuals' spatial positions within a moving group over successive trials. We found that certain individuals consistently occupied front positions in moving groups and also that it was typically these individuals that initiated group decisions. The number of individuals involved in leading the group varied according to the amount of information held by group members, with a greater number of changes in leadership in a novel compared to a relatively familiar environment. Finally, our results show that the occupation of lead positions in moving groups was not explained by characteristics such as dominance, size or sex, suggesting that certain individuals are predisposed to leadership roles. This suggests that being a leader or a follower may to some extent be an intrinsic property of the individual

    The influence of experience in orientation: GPS tracking of homing pigeons released over the sea after directional training

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    Flight experience is one of the factors that influences initial orientation of displaced homing pigeons (Columba livia). Prior studies showed a systematic dependence of initial orientation on previously flown direction. Using GPS data loggers, this study sought to examine the effect of previous directional training of 40 homing pigeons when they were released over the sea, in the absence of proximal landmarks, in a direction almost perpendicular to that of previous training flights. Our results demonstrated that previous directional training evoked a systematic and predicted deviation from the beeline over the sea that appeared as a compromise between the direction of training and the direction to the loft. Pigeons were able to efficiently correct their flight direction only once over land, where they flew significantly slower and less directly than over the sea

    Waiting time before release increases the motivation to home in homing pigeons (Columba livia)

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    When performing homing experiments with individual releases, pigeons have to wait in a transport box for a certain amount of time before being released and hence perceive the departure of companions. Quite often, the last pigeons disappear straightforward from the release site. The question is whether this reflects improved orientation because of prolonged exposure to the release place or whether it reflects increased homing motivation. By releasing pigeons from a familiar site, we investigated the effects of the time spent at the release site on homing performance, recording pigeons' flights with GPS loggers. Our results show that, despite individual peculiarities of flight patterns, the waiting time at release site had a positive effect on homing speed and time, and reduced the time spent circling around the release point. However, the overall path efficiency as derived from GPS tracking was not influenced. These results suggest that a longer waiting time before release improves homing performance and this is related not only to increased navigational abilities but also to increased homing motivation

    Long flights and age affect oxidative status of homing pigeons (Columba livia)

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    Flying is an energy demanding activity that imposes several physiological challenges on birds, such as increase in energy expenditure. Evidence from sports medicine shows that exhausting exercise may cause oxidative stress. Studies on avian flight have so far considered several blood parameters, such as uric acid, corticosteroids, or circulating free fatty acids, but only one study has analysed markers of oxidative stress in flying birds. In this study, we evaluated, for the first time, how different flight efforts affect the oxidative status using homing pigeons (Columba livia) as a model species. Two groups of pigeons flew for around 60 and 200 km, respectively. Pigeons that flew for 200 km had a 54% increase in oxidative damage as measured by serum reactive oxygen metabolites (ROMs), a 19% drop in total serum antioxidant capacity (OXY) and an 86% increase of oxidative stress (ROMs/OXYx1000). Older pigeons depleted more serum antioxidants regardless of the release distance. Among pigeons that flew the longer distance, heavier ones depleted less serum antioxidants. The results of the study suggest that long flights may cause oxidative stress, and that older individuals may experience higher physiological demands
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