2,718 research outputs found

    A decade of monitoring Atlantic cod Gadus morhua spawning aggregations in Massachusetts Bay using passive acoustics

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    © The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Caiger, P. E., Dean, M. J., DeAngelis, A. I., Hatch, L. T., Rice, A. N., Stanley, J. A., Tholke, C., Zemeckis, D. R., & Van Parijs, S. M. A decade of monitoring Atlantic cod Gadus morhua spawning aggregations in Massachusetts Bay using passive acoustics. Marine Ecology Progress Series, 635, (2020): 89-103, doi:10.3354/meps13219.Atlantic cod Gadus morhua populations in the northeast USA have failed to recover since major declines in the 1970s and 1990s. To rebuild these stocks, managers need reliable information on spawning dynamics in order to design and implement control measures; discovering cost-effective and non-invasive monitoring techniques is also favorable. Atlantic cod form dense, site-fidelic spawning aggregations during which they vocalize, permitting acoustic detection of their presence at such times. The objective of this study was to detect spawning activity of Atlantic cod using multiple fixed-station passive acoustic recorders to sample across Massachusetts Bay during the winter spawning period. A generalized linear modeling approach was used to investigate spatio-temporal trends of cod vocalizing over 10 consecutive winter spawning seasons (2007-2016), the longest such timeline of any passive acoustic monitoring of a fish species. The vocal activity of Atlantic cod was associated with diel, lunar, and seasonal cycles, with a higher probability of occurrence at night, during the full moon, and near the end of November. Following 2009 and 2010, there was a general decline in acoustic activity. Furthermore, the northwest corner of Stellwagen Bank was identified as an important spawning location. This project demonstrated the utility of passive acoustic monitoring in determining the presence of an acoustically active fish species, and provides valuable data for informing the management of this commercially, culturally, and ecologically important species.Thanks to Eli Bonnell, Genevieve Davis, Julianne Bonell, Samara Haver, and Eric Matzen for assistance in MARU deployments, Dana Gerlach and Heather Heenehan for help in passive acoustic data analysis, and the NEFSC passive acoustics group for useful discussions. Funding for 2007−2012 passive acoustic surveys was provided by Excelerate Energy and Neptune LNG to Cornell University. Fieldwork for 2013−2015 was funded through the 2013−2014 NOAA Saltonstall-Kennedy grant program (Award No. NA14NMF4270027), and jointly funded by The Nature Conservancy, Massachusetts Division of Marine Fisheries, and the Cabot Family Charitable Foundation. Funding for 2016 SoundTrap data was provided by NOAA’s Ocean Acoustics Program (4 Sanctuaries Project)

    Is youth unemployment really the major worry? (AOM)

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    Youth unemployment is neither the only nor the basic problem of the European labour market. The comparative analysis of unemployment data demonstrates that the unemployment of older people is even more serious. The article proves that the weight of young people in total unemployment has as a tendency been declining in the “inner periphery” of the EU, among them in Central and Eastern European member states (CEECs). The trend is just the opposite in the developed or “core” countries of the Union where youngsters took a higher share in total unemployment in 2012 than 10-12 years ago. In Europe there are millions of young people beyond the active unemployed who do not want to work or think they cannot find a job that fulfils their expectations and refuse to take part in any kind of education or training (NEETs-“Not in Employment, Education or Training”). By estimating the rate of NEETs in the adult population the article claims that the NEETs-phenomenon is not the differentia specifica of the youth. At the end the article details two suggestions for the mitigation of the problem. It concludes that the joblessness in Europe is an old and tendencially worsening problem that cannot be solved by particular policies

    Near real-time detection of low-frequency baleen whale calls from an autonomous surface vehicle: implementation, evaluation, and remaining challenges

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    © The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Baumgartner, M. F., Ball, K., Partan, J., Pelletier, L., Bonnell, J., Hotchkin, C., Corkeron, P. J., & Van Parijs, S. M. Near real-time detection of low-frequency baleen whale calls from an autonomous surface vehicle: implementation, evaluation, and remaining challenges. Journal of the Acoustical Society of America, 149(5), (2021): 2950-2962, https://doi.org/10.1121/10.0004817.Mitigation of threats posed to marine mammals by human activities can be greatly improved with a better understanding of animal occurrence in real time. Recent advancements have enabled low-power passive acoustic systems to be integrated into long-endurance autonomous platforms for persistent near real-time monitoring of marine mammals via the sounds they produce. Here, the integration of a passive acoustic instrument capable of real-time detection and classification of low-frequency (LF) tonal sounds with a Liquid Robotics wave glider is reported. The goal of the integration was to enable monitoring of LF calls produced by baleen whales over periods of several months. Mechanical noises produced by the platform were significantly reduced by lubricating moving parts with polytetrafluoroethylene, incorporating rubber and springs to decelerate moving parts and shock mounting hydrophones. Flow noise was reduced with the development of a 21-element hydrophone array. Surface noise produced by breaking waves was not mitigated despite experimentation with baffles. Compared to a well-characterized moored passive acoustic monitoring buoy, the system greatly underestimated the occurrence of sei, fin, and North Atlantic right whales during a 37-d deployment, and therefore is not suitable in its current configuration for use in scientific or management applications for these species at this time.Funding for this project was provided by the Environmental Security Technology Certification Program of the U.S. Department of Defense and the U.S. Navy's Living Marine Resources Program

    The ethical challenge of Touraine's 'living together'

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    In Can We Live Together? Alain Touraine combines a consummate analysis of crucial social tensions in contemporary societies with a strong normative appeal for a new emancipatory 'Subject' capable of overcoming the twin threats of atomisation or authoritarianism. He calls for a move from 'politics to ethics' and then from ethics back to politics to enable the new Subject to make a reality out of the goals of democracy and solidarity. However, he has little to say about the nature of such an ethics. This article argues that this lacuna could usefully be filled by adopting a form of radical humanism found in the work of Erich Fromm. It defies convention in the social sciences by operating from an explicit view of the 'is' and the 'ought' of common human nature, specifying reason, love and productive work as the qualities to be realised if we are to move closer to human solidarity. Although there remain significant philosophical and political differences between the two positions, particularly on the role to be played by 'the nation', their juxtaposition opens new lines of inquiry in the field of cosmopolitan ethics

    A double-edged sword: the merits and the policy implications of Google Translate in higher education

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    Machine translation, specifically Google Translate is freely available on a number of devices, and is improving in its ability to provide grammatically accurate translations. This development has the potential to provoke a major transformation in the internationalisation process at universities, since students may be, in the future, able to use technology to circumvent traditional language learning processes. While this is a potentially empowering move that may facilitate academic exchange and the diversification of the learner and researcher community at an international level, it is also a potentially problematic issue in two main respects. Firstly, the technology is at present unable to align to the socio-linguistic aspects of university level writing and may be misunderstood as a remedy to lack of writer language proficiency – a role it is not able to fulfil. Secondly, it introduces a new dimension to the production of academic work that may clash with Higher Education policy and, thus, requires legislation, in particular in light issues such as plagiarism and academic misconduct. This paper considers these issues against the background of English as a Global Lingua Franca, and argues two points. First of these is that HEIs need to develop an understanding and code of practice for the use of this technology. Secondly, three strands of potential future research will be presente

    Denying reciprocity

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    When individuals receive benefits as a result of the burdens assumed by other people, they are expected to make a return in similar form. To do otherwise is considered as a failure to treat those other people with appropriate respect. It is this which justifies the expectation that individuals share in the labour that is necessary to preserve just institutions and productive practices that characterise complex schemes of social cooperation. In this paper, I argue that where benefits do not meet thresholds specifying the expected function and efficacy of those benefits, this does not simply issue in a ‘downward adjustment’ in the work expectations and reciprocal demands that are made of people. Rather, it legitimates refusal to engage in productive labour even where limited benefits are still being received. Other costs and obligations emerge that contribute to the creation of disruptive political, economic and social associations. These not only replace the demands of reciprocity but actively target and disrupt the practices and exchanges that give form to reciprocity
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