48 research outputs found

    Habitat degradation negatively affects auditory settlement behavior of coral reef fishes

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    Coral reefs are increasingly degraded by climate-induced bleaching and storm damage. Reef recovery relies on recruitment of young fishes for the replenishment of functionally important taxa. Acoustic cues guide the orientation, habitat selection, and settlement of many fishes, but these processes may be impaired if degradation alters reef soundscapes. Here, we report spatiotemporally matched evidence of soundscapes altered by degradation from recordings taken before and after recent severe damage on Australia’s Great Barrier Reef. Postdegradation soundscapes were an average of 15 dB re 1 µPa quieter and had significantly reduced acoustic complexity, richness, and rates of invertebrate snaps compared with their predegradation equivalents. We then used these matched recordings in complementary light-trap and patch-reef experiments to assess responses of wild fish larvae under natural conditions. We show that postdegradation soundscapes were 8% less attractive to presettlement larvae and resulted in 40% less settlement of juvenile fishes than predegradation soundscapes; postdegradation soundscapes were no more attractive than open-ocean sound. However, our experimental design does not allow an estimate of how much attraction and settlement to isolated postdegradation soundscapes might change compared with isolated predegradation soundscapes. Reductions in attraction and settlement were qualitatively similar across and within all trophic guilds and taxonomic groups analyzed. These patterns may lead to declines in fish populations, exacerbating degradation. Acoustic changes might therefore trigger a feedback loop that could impair reef resilience. To understand fully the recovery potential of coral reefs, we must learn to listen

    Coral larvae move toward reef sounds

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    Free-swimming larvae of tropical corals go through a critical life-phase when they return from the open ocean to select a suitable settlement substrate. During the planktonic phase of their life cycle, the behaviours of small coral larvae (<1 mm) that influence settlement success are difficult to observe in situ and are therefore largely unknown. Here, we show that coral larvae respond to acoustic cues that may facilitate detection of habitat from large distances and from upcurrent of preferred settlement locations. Using in situ choice chambers, we found that settling coral larvae were attracted to reef sounds, produced mainly by fish and crustaceans, which we broadcast underwater using loudspeakers. Our discovery that coral larvae can detect and respond to sound is the first description of an auditory response in the invertebrate phylum Cnidaria, which includes jellyfish, anemones, and hydroids as well as corals. If, like settlement-stage reef fish and crustaceans, coral larvae use reef noise as a cue for orientation, the alleviation of noise pollution in the marine environment may gain further urgency.Mark J. A. Vermeij, Kristen L. Marhaver, Chantal M. Huijbers, Ivan Nagelkerken and Stephen D. Simpso

    Crop Updates 2010 - Crop Specific

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    This session covers twenty four papers from different authors: PLENARY 1. Challenges facing western Canadian cropping over the next 10 years, Hugh J Beckie, Research Centre, Agriculture and Agri-Food Canada, Saskatoon, Saskatchewan CROP SPECIFIC Breeding 2. The challenge of breeding canola hybrids – new opportunities for WA growers, Wallace Cowling, Research Director, Canola Breeders Western Australia Pty Ltd 3. Chickpea 2009 crop variety testing of germplasm developed by DAFWA/CLIMA/ICRISAT/COGGO alliance. Khan, TN1,3, Adhikari, K1,3, Siddique, K2, Garlinge, J1, Smith, L1, Morgan, S1 and Boyd, C1 1Department of Agriculture and Food, Western Australia (DAFWA), 2Insititute of Agriculture, The University of Western Australia (UWA), 3Centre for Legumes in Mediterranean Agriculture (CLIMA), The University of Western Australia 4. PBA Pulse Breeding Australia – 2009 Field Pea Results, Ian Pritchard1, Chris Veitch1, Colin Boyd1, Stuart Morgan1, Alan Harris1 and Tony Leonforte2, 1Department of Agriculture and Food, Western Australia, 2Department of Primary Industries, Victoria 5. PBA Pulse Breeding Australia – 2009 Chickpea Results, Ian Pritchard1, Chris Veitch1, Colin Boyd1, Murray Blyth1, Shari Dougal1 and Kristy Hobson2 1Department of Agriculture and Food, Western Australia, 2Department of Primary Industries, Victoria Decision Support 6. A tool for identifying problems in wheat paddocks, Ben Curtis and Doug Sawkins, Department of Agriculture and Food 7. DAFWA Seasonal Forecast for 2010, Stephens, D, Department of Agriculture and Food, Western Australian, Climate and Modelling Group Disease 8. Enhancement of black spot resistance in field pea, Kedar Adhikari, T Khan, S Morgan and C Boyd, Department of Agriculture and Food, 9. fungicide management of yellow spot in wheat, Ciara Beard, Kith Jayasena, Kazue Tanaka and Anne Smith, Department of Agriculture and Food 10. Resistance to infection by Beet western yellows virus in four Australian canola varieties, Brenda Coutts and Roger Jones, Department of Agriculture and Food 11. Yellow spot carryover risk from stubble in wheat-on-wheat rotations, Jean Galloway, Pip Payne and Tess Humphreys, Department of Agriculture and Food 12. Fungicides for the future: Management of Barley Powdery Mildew and Leaf Rust, Kith Jayasena, Kazue Tanaka and William MacLeod, Department of Agriculture and Food 13. 2009 canola disease survey and management options for blackleg and Sclerotinia in 2010, Ravjit Khangura, WJ MacLeod, M Aberra and H Mian, Department of Agriculture and Food 14. Impact of variety and fungicide on carryover of stubble borne inoculum and yellow spot severity in continuous wheat cropping, Geoff Thomas, Pip Payne, Tess Humphreys and Anne Smith, Department of Agriculture and Food 15. Limitations to the spread of Wheat streak mosaic virus by the Wheat curl mite in WA during 2009, Dusty Severtson, Peter Mangano, Brenda Coutts, Monica Kehoe and Roger Jones, Department of Agriculture and Food 16. Viable solutions for barley powdery mildew, Madeline A. Tucker, Australian Centre for Necrotrophic Fungal Pathogens, Murdoch University Marketing 17. The importance of varietal accreditation in a post-deregulation barley marketing environment, Neil Barker, Barley Australia 18. Can Australia wheat meet requirements for a new middle east market? Robert Loughman, Larisa Cato, Department of Agriculture and Food, and Ken Quail, BRI Australia VARIETY PERFORMANCE 19. Sowing rate and time for hybrid vs open-pollinated canola, Mohammad Amjad and Mark Seymour, Department of Agriculture and Food 20. HYOLA® National Hybrid vs OP Canola Hybrid F1 vs Retained Seed Generation Trial Results and recommendations for growers, Justin Kudnig, Mark Thompson, Anton Mannes, Michael Uttley, Chris Fletcher, Andrew Etherton, Nick Joyce and Kate Light, Pacific Seeds Australia 21. HYOLA® National Hybrid vs OP Canola Sowing Rate Trial Results and plant population recommendations for Australian growers, Justin Kudnig, Mark Thompson, Anton Mannes, Michael Uttley, Andrew Etherton, Chris Fletcher, Nick Joyce and Kate Light, Pacific Seeds Australia; Peter Hamblin, Agritech Research Young, NSW, Michael Lamond, Agrisearch, York, Western Australia 22. Desi chickpea agronomy for 2010, Alan Meldrum, Pulse Australia and Wayne Parker, Department of Agriculture and Food 23. New wheat varieties – exploit the benefits and avoid the pitfalls, Steve Penny, Sarah Ellis, Brenda Shackley, Christine Zaicou, Shahajahan Miyan, Darshan Sharma and Ben Curtis, Department of Agriculture and Food 24. The influence of genetics and environment on the level of seed alkaloid in narrow-leafed lupins, Greg Shea1, Bevan Buirchell1, David Harris2 and Bob French1, 1Department of Agriculture and Food, 2ChemCentr

    Mortality and pulmonary complications in patients undergoing surgery with perioperative SARS-CoV-2 infection: an international cohort study

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    Background: The impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on postoperative recovery needs to be understood to inform clinical decision making during and after the COVID-19 pandemic. This study reports 30-day mortality and pulmonary complication rates in patients with perioperative SARS-CoV-2 infection. Methods: This international, multicentre, cohort study at 235 hospitals in 24 countries included all patients undergoing surgery who had SARS-CoV-2 infection confirmed within 7 days before or 30 days after surgery. The primary outcome measure was 30-day postoperative mortality and was assessed in all enrolled patients. The main secondary outcome measure was pulmonary complications, defined as pneumonia, acute respiratory distress syndrome, or unexpected postoperative ventilation. Findings: This analysis includes 1128 patients who had surgery between Jan 1 and March 31, 2020, of whom 835 (74·0%) had emergency surgery and 280 (24·8%) had elective surgery. SARS-CoV-2 infection was confirmed preoperatively in 294 (26·1%) patients. 30-day mortality was 23·8% (268 of 1128). Pulmonary complications occurred in 577 (51·2%) of 1128 patients; 30-day mortality in these patients was 38·0% (219 of 577), accounting for 81·7% (219 of 268) of all deaths. In adjusted analyses, 30-day mortality was associated with male sex (odds ratio 1·75 [95% CI 1·28–2·40], p\textless0·0001), age 70 years or older versus younger than 70 years (2·30 [1·65–3·22], p\textless0·0001), American Society of Anesthesiologists grades 3–5 versus grades 1–2 (2·35 [1·57–3·53], p\textless0·0001), malignant versus benign or obstetric diagnosis (1·55 [1·01–2·39], p=0·046), emergency versus elective surgery (1·67 [1·06–2·63], p=0·026), and major versus minor surgery (1·52 [1·01–2·31], p=0·047). Interpretation: Postoperative pulmonary complications occur in half of patients with perioperative SARS-CoV-2 infection and are associated with high mortality. Thresholds for surgery during the COVID-19 pandemic should be higher than during normal practice, particularly in men aged 70 years and older. Consideration should be given for postponing non-urgent procedures and promoting non-operative treatment to delay or avoid the need for surgery. Funding: National Institute for Health Research (NIHR), Association of Coloproctology of Great Britain and Ireland, Bowel and Cancer Research, Bowel Disease Research Foundation, Association of Upper Gastrointestinal Surgeons, British Association of Surgical Oncology, British Gynaecological Cancer Society, European Society of Coloproctology, NIHR Academy, Sarcoma UK, Vascular Society for Great Britain and Ireland, and Yorkshire Cancer Research

    Acoustic surveying for beaked whales in the Coral Sea as a mitigation measure for naval exercises

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    Beaked whales have been over-represented in whale strandings that have occurred at similar times and places of some naval exercises in the northern hemisphere. Although whale strandings are common, it is unusual to find beaked whales stranded in such large numbers. Consequently, the environmental management of naval exercises requires mitigation measures to avoid potential impact on beaked whales. This requires some knowledge of beaked whale distributions and behavior, but little is known about beaked whales, less than for all other whales. Beaked whales are small whales that inhabit deep water. They are particularly elusive and rarely seen at sea. Much of what little is known about them results from the few that have been washed ashore. Visual surveying has proved to be generally ineffective. Beaked whale vocalizations are, however, sufficiently distinctive to allow passive acoustic detection and classification [1]. The sounds are sufficiently distinctive to distinguish them from those of other toothed whales, though these distinctions are subtle. All toothed whales produce echolocation clicks or pulses with a small number of cycles and most energy at ultrasonic frequencies. Beaked whale clicks can be distinguished by the frequency range, duration and number of cycles but other species have clicks that are close in one or other of the characteristics. In 2008 and 2009 we conducted two passive acoustic surveys of a naval exercise area in deep water in the Coral Sea (north east of Fraser Is.) in an attempt to determine the distributions of beaked whales in the area of about 18, 900 square km. Each survey was three weeks duration and involved acoustic and visual observations. A towed array of two hydrophones with frequency response to 150 kHz, and two drifting systems with hydrophones at 400 m depth and response to 96 kHz were used (beaked whale sounds have an upper limit of about 80 kHz). The drifting systems were tracked using a radio link suspended from a buoy that transmitted the GPS position of the buoy at regular intervals. Nothing was known about the presence of beaked whales in the area, but there are records of stranding of four species on the nearest part of the Queensland coast. Two of these species were the same as those recorded with the DTAGs. Almost 400 h of recordings were obtained using the towed array and almost 200 h from the drifting systems. Thousands of toothed whale clicks were recorded. Some of the clicks recorded were remarkably similar to those published for beaked whales [1, 2] and so were identified as beaked whales. Only a small proportion of clicks were typical of beaked whale sounds and these were recorded mainly over the steep slopes of two coral islands. The analysis is continuin

    Listening to ocean sounds: using underwater acoustics to study marine animals

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    Marine animals make extensive use of sound in an environment where vision is usually very limited but where sound travels to great distances. Their sounds can provide information about their distributions and abundance as well as providing insights into their behaviour. This requires more than just studying their vocalisations – it also requires knowledge of their acoustic environment and the way that this affects their use of sound. This paper presents some results of recent experiments illustrating these themes, including some measurements of the acoustic environment required to interpret the behavioural studies. Beaked whales are small elusive whales that are rarely seen and little is known of their distributions. Visual surveys are usually ineffective. Cruises in the Coral Sea in 2008 and 2009 trialled acoustic methods of detecting beaked whales and surveyed an area of more than 19,000 km2 which included continental shelf, slop and deep water. Large numbers of their distinctive click sounds were detected in deep water near the continental slope and the steep sides of islands. Humpback whales are very vocal and their use of sound is an important part of their behaviour. In a series of experiments, we have studied the behaviour and sound production of migrating humpback whales and tracked their movements using their sounds. As part of this we measured the transmission loss of the beach side study area to allow us to calculate the source levels (vocal outputs) of the whales from the received levels, and how these varied with behaviour and background noise. White noise of known source level, filtered in octave bands, was transmitted using an underwater loudspeaker. Measurements at various distances showed that the transmission loss for the sloping beach area was a little less than expected for free field transmission (spherical spreading)

    Ten months of temporal variation in the clinical journey of hospitalised patients with COVID-19: An observational cohort.

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    BACKGROUND: There is potentially considerable variation in the nature and duration of the care provided to hospitalised patients during an infectious disease epidemic or pandemic. Improvements in care and clinician confidence may shorten the time spent as an inpatient, or the need for admission to an intensive care unit (ICU) or high dependency unit (HDU). On the other hand, limited resources at times of high demand may lead to rationing. Nevertheless, these variables may be used as static proxies for disease severity, as outcome measures for trials, and to inform planning and logistics. METHODS: We investigate these time trends in an extremely large international cohort of 142,540 patients hospitalised with COVID-19. Investigated are: time from symptom onset to hospital admission, probability of ICU/HDU admission, time from hospital admission to ICU/HDU admission, hospital case fatality ratio (hCFR) and total length of hospital stay. RESULTS: Time from onset to admission showed a rapid decline during the first months of the pandemic followed by peaks during August/September and December 2020. ICU/HDU admission was more frequent from June to August. The hCFR was lowest from June to August. Raw numbers for overall hospital stay showed little variation, but there is clear decline in time to discharge for ICU/HDU survivors. CONCLUSIONS: Our results establish that variables of these kinds have limitations when used as outcome measures in a rapidly evolving situation. FUNDING: This work was supported by the UK Foreign, Commonwealth and Development Office and Wellcome [215091/Z/18/Z] and the Bill & Melinda Gates Foundation [OPP1209135]. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript
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