496 research outputs found

    Management of Antarctic baleen whales amid past exploitation, current threats and complex marine ecosystems

    Get PDF
    As baleen whales recover from severe exploitation, they are probably subject to a wide variety of threats within the Antarctic marine ecosystem, including directed take. Here we review both the management and current status of Antarctic baleen whales and consider those threats likely to impact on them. Threats range from global problems - marine pollution and climate change - to localized issues including shipping, habitat disturbance, unregulated wildlife tourism and fishery activities. We identify the most pressing anthropogenic threats to baleen whales including scientific whaling and climate change. It is unclear whether current management approaches will be able to effectively encompass all these threats while also accounting both for the differing levels of scientific understanding and for the differing recovery rates of the whale species. For management we recommend the following: 1) incorporation of both ecosystem considerations and the suite of identified threats not limited to direct take, 2) identification of measurable indicators of changes in whales that allow more certainty in monitoring of populations and the environment, and 3) recognition of significant relationships between baleen whales and habitat features to provide information on distribution and use

    Feasibility study to investigate caking in washing powder formulations using a Freeman FT4 powder rheometer

    Get PDF
    Because of legislation and environmental concerns, washing powder manufacturers have phased out phosphate builders in favour of substitutes such as sodium carbonate. This has meant that the new formulations have a greater tendency towards unwanted agglomeration (caking), based on moisture uptake and migration. This study examines the feasibility of using a Freeman FT4 powder rheometer to examine the effect of moisture migration, using the Basic Flow Energy (BFE) value to compare formulations of sodium carbonate content 27-37% and sodium sulphate content 10-20% by mass after 7 days exposure to 80% relative humidity at 20Ā°C. The results showed that 31% and 33% sodium carbonate formulations were the most resistant to caking, with 27% and 37% being the most susceptible under the test conditions. Using the method of Brockbank et al. (2015), the FT4 was also used to detect the presence of a hard crust; under the test conditions, no hard crust was found. However, the presence of soft caking was detected in the force-height profile, showing a less abrupt transition

    Odontocetes of the Southern Ocean sanctuary

    Get PDF
    Twenty-eight odontocete species were identified as occupying sub-Antarctic and Antarctic habitat covered by the 1994 IWC established Southern Ocean Sanctuary. Toothed whales evidently play an important part in the Antarctic polar ecosystem. Twenty-two species are autochthonous in showing a regular, apparently year-round, presence in the Sanctuary: Physeter macrocephalus, Kogia breviceps, Orcinus orca, Globicephala melas edwardii, Pseudorca crassidens, Lagenorhynchus cruciger, Lagenorhynchus obscurus, Lissodelphis peronii, Cephalorhynchus commersonii, Cephalorhynchus hectori, Tursiops truncatus, Delphinus delphis, Phocoena dioptrica, Hyperoodon planifrons, Berardius arnuxii, Ziphius cavirostris, Tasmacetus shepherdi, Mesoplodon layardii, Mesoplodon traversii, Mesoplodon grayi, Mesoplodon bowdoini and Mesoplodon hectori. Six species are considered vagrants into the Sanctuary: Kogia sima, Grampus griseus, Steno bredanensis, Mesoplodon peruvianus, Mesoplodon densirostris and Mesoplodon mirus. However, vagrant status of these three mesoplodonts is only provisionally assigned, considering that improved knowledge of diagnostic features of beaked whales should, as in recent years, continue to facilitate at sea identification. Two species are considered as having a ā€˜contiguousā€™ range (records less than 2Ā° north of Sanctuary boundaries): Mesoplodon ginkgodens (at 39Ā°S) and Mesoplodon mirus (at 38Ā°24ā€™S). The habitual southern range of at least four odontocetes extends significantly farther poleward than expected. G. melas edwardii is regularly encountered south of the Antarctic Polar Front, much like M. grayi which is known to reach the Ross Sea ice edge (ca. 67Ā°S). Z. cavirostris and L. obscurus cross the Polar Front occasionally. The distribution of M. peruvianus and M. traversii and their relation to SST are unclear. Their southernmost records, 42Ā°31ā€™S and 44Ā°17ā€™S respectively, may either be extralimital or, more likely, reflect ordinary austral range. Temporally non-aligned distribution patterns of Hyperoodon planifrons in Antarctic and South African waters may suggest stock segregation

    Using historical data to detect temporal changes in the abundances of intertidal species on Irish shores

    Get PDF
    An historical data set, collected in 1958 by Southward and Crisp, was used as a baseline for detecting change in the abundances of species in the rocky intertidal of Ireland. In 2003, the abundances of each of 27 species was assessed using the same methodologies (ACFOR [which stands for the categories: abundant, common, frequent, occasional and rare] abundance scales) at 63 shores examined in the historical study. Comparison of the ACFOR data over a 45-year period, between the historical survey and re-survey, showed statistically significant changes in the abundances of 12 of the 27 species examined. Two species (one classed as northern and one introduced) increased significantly in abundance while ten species (five classed as northern, one classed as southern and four broadly distributed) decreased in abundance. The possible reasons for the changes in species abundances were assessed not only in the context of anthropogenic effects, such as climate change and commercial exploitation, but also of operator error. The error or differences recorded among operators (i.e. research scientists) when assessing species abundance using ACFOR categories was quantified on four shores. Significant change detected in three of the 12 species fell within the margin of operator error. This effect of operator may have also contributed to the results of no change in the other 15 species between the two census periods. It was not possible to determine the effect of operator on our results, which can increase the occurrence of a false positive (Type 1) or of a false negative (Type 2) outcom

    Effect of processing variables and bulk composition on the surface composition of spray dried powders of a model food system

    Get PDF
    Abstract The surface compositions of food powders created from spray drying solutions containing various ratios of sodium caseinate, maltodextrin and soya oil have been analysed by Electron Spectroscopy for Chemical Analysis. The results show significant enrichment of oil at the surface of particles compared to the bulk phase and, when the non-oil components only are considered, a significant surface enrichment of sodium caseinate also. The degree of surface enrichment of both oil and sodium caseinate was found to increase with decreasing bulk levels of the respective components. Surface enrichment of oil was also affected by processing conditions (emulsion drop size and drying temperature), but surface enrichment of sodium caseinate was relatively insensitive to these. The presence of "pock marks" on the particle surfaces strongly suggests that the surface oil was caused by rupturing of emulsion droplets at the surface as the surrounding matrix contracts and hardens

    International Whaling Commissionā€“Southern Ocean GLOBEC/CCAMLR collaboration. Scientific Committee document SC/55/E10, International Whaling Commission, May-June 2003, Berlin, Germany

    Get PDF
    Collaboration between the International Whaling Commission, and national programs conducting multidisciplinary ecosystem research in the Antarctic under Southern Ocean Global Ecosystem Dynamics (SO GLOBEC) program and the Commission for the Convention on Antarctic Marine Living Resources (CCAMLR) occurred during five research cruises between April 2002 and April 2003. Visual survey, passive acoustic and tissue biopsy work was conducted by IWC observers and collaborating passive acoustics scientists. Reported here are the preliminary results from these cruises: mapped distribution patterns of cetaceans from visual survey sighting data; individual photo identification records; species identification and positions of animals recorded on sonobuoys; and descriptions of environmental conditions observed or recorded as part of the multidisciplinary effort
    • ā€¦
    corecore