11 research outputs found

    Mark-recapture validates the use of photo-identification for the widely distributed blue-spotted ribbontail ray, Taeniura lymma

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    The ability to identify individual animals can provide valuable insights into the behaviour, life history, survivorship, and demographics of wild populations. Photo-identification (photo-ID) uses unique natural markings to identify individuals and can be effective for scalable and non-invasive research on marine fauna. The successful application of photo-ID requires that chosen distinguishing markings are unique to individuals and persist over time. In this study, we validate the use of dorsal spot patterns for identifying individual blue-spotted ribbontail rays (Taeniura lymma) in conjunction with traditional tagging methods. Spot patterns were unique among T. lymma with 90.3% of individuals correctly identified using I3S photo-matching software from images taken up to 496 days apart. In comparison, traditional physical tagging methods showed a tag loss rate of 27% and a maximum tag retention period of only 356 days. Our findings demonstrate the effectiveness of photo-ID as a tool to monitor populations and better understand the ecology of the blue-spotted ribbontail ray without the need for physical tagging. The validation of photo-ID for this widespread species is important as it enables behavioural and demographic changes to be easily tracked in relation to coastal threats such as human development and habitat degradation.</p

    Neotype designation and re-description of Forsskål’s reticulate whipray Himantura uarnak

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    International audienceA continuing impediment to the taxonomy of the reticulate whipray Himantura spp. species complex is the absence of a type specimen for H. uarnak (Gmelin [ex Forsskål], 1789). Here, reticulate whipray specimens were sampled from the Jeddah region in the Red Sea, the assumed type locality of H. uarnak, and characterized genetically at the cytochrome-oxidase subunit 1 (CO1) locus. One of these specimens now in the fish collection of the California Academy of Sciences was designated as neotype. The maximum-likelihood phylogeny of all available CO1 gene sequences from the genus Himantura had the following topology: ((H. leoparda, H. uarnak), (H. undulata, (Himantura sp. 2, (H. australis + Himantura sp. 1))), H. tutul), where H. uarnak haplotypes formed a distinct lineage sister to H. leoparda. Based on these CO1 gene sequences, the geographic distribution of H. uarnak includes the eastern Mediterranean, the Red Sea, the East African coast, and the Arabian Sea. At least one lineage in the reticulate whipray species complex remains to be named

    Neotype designation and re-description of Forsskål’s reticulate whipray Himantura uarnak

    No full text
    International audienceA continuing impediment to the taxonomy of the reticulate whipray Himantura spp. species complex is the absence of a type specimen for H. uarnak (Gmelin [ex Forsskål], 1789). Here, reticulate whipray specimens were sampled from the Jeddah region in the Red Sea, the assumed type locality of H. uarnak, and characterized genetically at the cytochrome-oxidase subunit 1 (CO1) locus. One of these specimens now in the fish collection of the California Academy of Sciences was designated as neotype. The maximum-likelihood phylogeny of all available CO1 gene sequences from the genus Himantura had the following topology: ((H. leoparda, H. uarnak), (H. undulata, (Himantura sp. 2, (H. australis + Himantura sp. 1))), H. tutul), where H. uarnak haplotypes formed a distinct lineage sister to H. leoparda. Based on these CO1 gene sequences, the geographic distribution of H. uarnak includes the eastern Mediterranean, the Red Sea, the East African coast, and the Arabian Sea. At least one lineage in the reticulate whipray species complex remains to be named

    Neotype designation and re-description of Forsskal's reticulate whipray Himantura uarnak

    No full text
    A continuing impediment to the taxonomy of the reticulate whipray Himantura spp. species complex is the absence of a type specimen for H. uarnak (Gmelin [ex Forsskal], 1789). Here, reticulate whipray specimens were sampled from the Jeddah region in the Red Sea, the assumed type locality of H. uarnak, and characterized genetically at the cytochrome-oxidase subunit 1 (CO1) locus. One of these specimens now in the fish collection of the California Academy of Sciences was designated as neotype. The maximum-likelihood phylogeny of all available CO1 gene sequences from the genus Himantura had the following topology: ((H. leoparda, H. uarnak), (H. undulata, (Himantura sp. 2, (H. australis + Himantura sp. 1))), H. tutul), where H. uarnak haplotypes formed a distinct lineage sister to H. leoparda. Based on these CO1 gene sequences, the geographic distribution of H. uarnak includes the eastern Mediterranean, the Red Sea, the East African coast, and the Arabian Sea. At least one lineage in the reticulate whipray species complex remains to be named

    Low diversity and abundance of predatory fishes in a peripheral coral reef ecosystem

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    Abstract Semi‐enclosed seas are often associated with elevated local threats and distinct biogeographic patterns among marine fishes, but our understanding of how fish assemblage dynamics vary in relation to relatively small semi‐enclosed seas (e.g., the Gulf of Aqaba) remains limited. Baited remote underwater video surveys (n = 111) were conducted across ~300 km of coral reef habitats in the Gulf of Aqaba and the northern Red Sea. A total of 55 predatory fish species were detected, with less than half of all species (n = 23) observed in both basins. Relative abundance patterns between the Gulf of Aqaba and the northern Red Sea were variable among taxa, but nearly twice as many predatory fish were observed per unit of effort in the northern Red Sea. In general, assemblages in both basins were dominated by three taxa (Epinephelinae, Carangidae, and Lethrinidae). Large‐bodied and threatened species were recorded at very low abundances. Multivariate analysis revealed distinct assemblage structuring of coral reef predators between the Gulf of Aqaba and the northern Red Sea. Most of the species driving these differences were recorded in both basins, but occurred at varying levels of abundance. Environmental factors were largely unsuccessful in explaining variation in assemblage structuring. These findings indicate that biological assemblages in the Gulf of Aqaba are more distinct than previously reported and that reef fish assemblage structuring can occur even within a relatively small semi‐enclosed sea. Despite inter‐basin assemblage structuring, the overall low abundance of vulnerable fish species is suggestive of overexploitation in both the Gulf of Aqaba and the northern Red Sea of Saudi Arabia. As the region surveyed is currently undergoing large‐scale coastal development, the results presented herein aim to guide spatial management and recovery plans for these coral reef systems in relation to this development

    Measuring mental wellbeing among adolescents : a systematic review of instruments

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    Globally, promoting mental wellbeing among adolescents is of great public health and social significance. However, less is known about advances in measures of mental wellbeing, relevant for use in mental health interventions, which are age-appropriate and acceptable for use among adolescents. Comprehensive assessment includes multiple aspects of mental wellbeing, as well as positive indicators of feeling and functioning. This review used systematic review methods, guided by PRISMA, to identify and assess comprehensive instruments in terms of their content, conceptual relevance for youth, and responsiveness to change. Ryan and Deci’s framework for mental wellbeing, grounded in hedonic and eudaimonic perspectives, was applied to assess the preponderance of feeling and functioning items for each instrument. The review identified 11 instruments that fit specified inclusion criteria. Only four of the scales were developed for adolescents. Though the scales varied in their preponderance of items, all scales encompassed at least one indicator of both feeling and functioning. Findings emphasize the importance of validating adult-developed instruments for youth and ensuring the instrument’s cultural and conceptual relevance within groups of adolescents. As promoting mental wellbeing becomes critical to the field of practice, practitioners need access to relevant and acceptable measures

    Cellulose nanomaterials review: structure, properties and nanocomposites

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    This critical review provides a processing-structure-property perspective on recent advances in cellulose nanoparticles and composites produced from them. It summarizes cellulose nanoparticles in terms of particle morphology, crystal structure, and properties. Also described are the self-assembly and rheological properties of cellulose nanoparticle suspensions. The methodology of composite processing and resulting properties are fully covered, with an emphasis on neat and high fraction cellulose composites. Additionally, advances in predictive modeling from molecular dynamic simulations of crystalline cellulose to the continuum modeling of composites made with such particles are reviewed (392 references)
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