5 research outputs found

    Population connectivity of the highly migratory shortfin mako (Isurus oxyrinchus Rafinesque 1810) and implications for management in the Southern Hemisphere

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    Published: 20 November 2018In this paper we combine analyses of satellite telemetry and molecular data to investigate spatial connectivity and genetic structure among populations of shortfin mako (Isurus oxyrinchus) in and around Australian waters, where this species is taken in recreational and commercial fisheries. Mitochondrial DNA data suggest matrilineal substructure across hemispheres, while nuclear DNA data indicate shortfin mako may constitute a globally panmictic population. There was generally high genetic connectivity within Australian waters. Assessing genetic connectivity across the Indian Ocean basin, as well as the extent that shortfin mako exhibit sex biases in dispersal patterns would benefit from future improved sampling of adult size classes, particularly of individuals from the eastern Indian Ocean. Telemetry data indicated that Australasian mako are indeed highly migratory and frequently make long-distance movements. However, individuals also exhibit fidelity to relatively small geographic areas for extended periods. Together these patterns suggest that shortfin mako populations may be genetically homogenous across large geographical areas as a consequence of few reproductively active migrants, although spatial partitioning exists. Given that connectivity appears to occur at different scales, management at both the national and regional levels seems most appropriate.Shannon Corrigan, Andrew D. Lowther, Luciano B. Beheregaray, Barry D. Bruce, Geremy Cliff, Clinton A. Duffy, Alan Foulis, Malcolm P. Francis, Simon D. Goldsworthy, John R. Hyde, Rima W. Jabado, Dovi Kacev, Lindsay Marshall, Gonzalo R. Mucientes, Gavin J. P. Naylor, Julian G. Pepperell, Nuno Queiroz, William T. White, Sabine P. Wintner and Paul J. Roger

    Following the chain to elusive anglers

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    Obtaining reliable estimates of important parameters from recreational fisheries is problematic but critical for stock assessment and effective resource management. Sampling methodologies based on traditional design-based sampling theory, is inadequate in obtaining representative catch and effort data, social or demographical characterization, or fisher behaviour from small hard-to-reach components within recreational fisheries (e.g. specialized sport fisheries) that may account for the majority of the catch for some species. A model-based approach to sampling is necessary. Researchers in other disciplines including epidemiology and social sciences routinely survey rare or 'hidden' populations within the general community by penetration of social networks rather than by interception of individuals. We encourage fisheries researchers to rethink survey designs and consider the social elements of recreational fishing. Employing chain-referral methods, such as respondent-driven sampling (RDS), may be a statistically robust and cost-effective option for sampling elusive sub-elements within recreational fisheries. Chain-referral sampling methodology is outlined and an example of a complemented 'RDS-recapture' survey design is introduced as a cost-effective application to estimating total catch in recreational fisheries

    Global spatial risk assessment of sharks under the footprint of fisheries

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    Brucellosis is a highly contagious zoonosis affecting humans and a wide range of domesticated and wild animal species. An important element for effective disease containment is to improve knowledge, attitudes and practices (KAP) of afflicted communities. This study aimed to assess the KAP related to brucellosis at the human–animal interface in an endemic area of Egypt and to identify the risk factors for human infection. A matched case–control study was conducted at the central fever hospitals located in six governorates in northern Egypt. Face‐to‐face interviews with cases and controls were conducted using a structured questionnaire. In total, 40.7% of the participants owned farm animals in their households. The overall mean practice score regarding animal husbandry, processing and consumption of milk and dairy products were significantly lower among cases compared with controls (−12.7 ± 18.1 vs. 0.68 ± 14.2, respectively; p < .001). Perceived barriers for notification of animal infection/abortion were predominate among cases and positively correlated with participants’ education. The predictors of having brucellosis infection were consumption of unpasteurized milk or raw dairy products and practicing animal husbandry. Applying protective measures against infection significantly reduced its risk. A model predicting risk factors for brucellosis among those who own animal showed that frequent abortions per animal increased the chance for brucellosis infection among human cases by 50‐fold (95% CI: 8.8–276.9), whereas the use of protective measures in animal care reduced the odds (OR = 0.11 [95% CI: 0.03–0.45]). In conclusion, consumption of unprocessed dairy products was equally important as contact with infected/aborted animals as major risk factors for Brucella spp. infection among humans in Egypt. There is poor knowledge, negative attitudes and risky behaviours among villagers which can perpetuate the risk of brucellosis transmission at the human–animal interface. This supports the need for integrating health education into the national brucellosis control programme

    Overview of the JET preparation for deuterium–tritium operation with the ITER like-wall

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