Large predatory coral trout species unlikely to meet increasing energetic demands in a warming ocean

Increased ocean temperature due to climate change is raising metabolic demands and energy requirements of marine ectotherms. If productivity of marine systems and fisheries are to persist, individual species must compensate for this demand through increasing energy acquisition or decreasing energy expenditure. Here we reveal that the most important coral reef fishery species in the Indo-west Pacific, the large predatory coral trout Plectropomus leopardus (Serranidae), can behaviourally adjust food intake to maintain body-condition under elevated temperatures, and acclimate over time to consume larger meals. However, these increased energetic demands are unlikely to be met by adequate production at lower trophic levels, as smaller prey species are often the first to decline in response to climate-induced loss of live coral and structural complexity. Consequently, ubiquitous increases in energy consumption due to climate change will increase top-down competition for a dwindling biomass of prey, potentially distorting entire food webs and associated fisheries

Effects of climate change on reproduction,larval development, and adult health of coral trout (Plectropomus spp.)

Climate change is emerging as the single greatest threat to coral-reef ecosystems.The most immediate impacts will be a loss of diversity and changes to fish community composition and may lead to eventual declines in abundance and productivity of key fisheries species. A key component of this research is to assess effects of projected changes in environmental conditions (temperature and ocean acidity) due to climate change on reproduction, growth and development of coral trout (Plectropomus leopardis).Ultimately, this research will fill key knowledge gaps about climate change impacts on larger fishes, which are fundamental to optimizing resilience-based management, and in turn improve the adaptive capacity of industries and communities along the Great Barrier Reef

Recent advances in understanding the effects of climate change on coral reefs

Climate change is one of the greatest threats to the persistence of coral reefs. Sustained and ongoing increases in ocean temperatures and acidification are altering the structure and function of reefs globally. Here, we summarise recent advances in our understanding of the effects of climate change on scleractinian corals and reef fish. Although there is considerable among-species variability in responses to increasing temperature and seawater chemistry, changing temperature regimes are likely to have the greatest influence on the structure of coral and fish assemblages, at least over short–medium timeframes. Recent evidence of increases in coral bleaching thresholds, local genetic adaptation and inheritance of heat tolerance suggest that coral populations may have some capacity to respond to warming, although the extent to which these changes can keep pace with changing environmental conditions is unknown. For coral reef fishes, current evidence indicates increasing seawater temperature will be a major determinant of future assemblages, through both habitat degradation and direct effects on physiology and behaviour. The effects of climate change are, however, being compounded by a range of anthropogenic disturbances, which may undermine the capacity of coral reef organisms to acclimate and/or adapt to specific changes in environmental conditions

Known predators of crown-of-thorns starfish (Acanthaster spp.) and their role in mitigating, if not preventing, population outbreaks

Predatory release has long been considered a potential contributor to population outbreaks of crown-of-thorns starfish (CoTS; Acanthaster spp.). This has initiated extensive searches for potentially important predators that can consume large numbers of CoTS at high rates, which are also vulnerable to over-fishing or reef degradation. Herein, we review reported predators of CoTS and assess the potential for these organisms to exert significant mortality, and thereby prevent and/or moderate CoTS outbreaks. In all, 80 species of coral reef organisms (including fishes, and motile and sessile invertebrates) are reported to predate on CoTS gametes (three species), larvae (17 species), juveniles (15 species), adults (18 species) and/or opportunistically feed on injured (10 species) or moribund (42 species) individuals within reef habitats. It is clear however, that predation on early life-history stages has been understudied, and there are likely to be many more species of reef fishes and/or sessile invertebrates that readily consume CoTS gametes and/or larvae. Given the number and diversity of coral reef species that consume Acanthaster spp., most of which (e.g., Arothron pufferfishes) are not explicitly targeted by reef-based fisheries, links between overfishing and CoTS outbreaks remain equivocal. There is also no single species that appears to have a disproportionate role in regulating CoTS populations. Rather, the collective consumption of CoTS by multiple different species and at different life-history stages is likely to suppress the local abundance of CoTS, and thereby mediate the severity of outbreaks. It is possible therefore, that general degradation of reef ecosystems and corresponding declines in biodiversity and productivity, may contribute to increasing incidence or severity of outbreaks of Acanthaster spp. However, it seems unlikely that predatory release in and of itself could account for initial onset of CoTS outbreaks. In conclusion, reducing anthropogenic stressors that reduce the abundance and/or diversity of potential predatory species represents a “no regrets” management strategy, but will need to be used in conjunction with other management strategies to prevent, or reduce the occurrence, of CoTS outbreaks

Wheat yield and quality as influenced by reduced tillage in organic farming

Organic farmers are interested in soil conservation by reduced tillage, techniques well known in conventional agriculture to protect soil quality and limit labor time and energy costs. However, organic farming and reduced tillage can modify weeds, soil structure, and thus soil nitrogen (N) mineralization which strongly influences wheat yield and quality. The main objectives of this study were to analyze how reduced tillage applied to organic wheat influenced (1) grain yield, protein concentration, and weed infestation; (2) deoxynivalenol (DON) contamination on grain; (3) technological quality parameters such as dry gluten, zeleny index, falling number, and gluten index; (4) protein composition (F1, F2, F3, F4, and F5 fractions, and UPP, gliadin/glutenin ratio); and (5) baking test. For this purpose, we analyzed five site-years of data from winter wheat crops where mouldboard ploughing and reduced tillage were compared in three experimental trials (two in France and one in Switzerland). Main results concern wheat yields: the effect of reduced tillage on wheat yield was influenced by several factors such as weed competition. No significant increase in mycotoxin content (DON) due to reduced tillage was detected. Contamination with DON was always below the European threshold for human consumption. The technological quality parameters were less affected by the tillage treatments than grain yield: protein content, gluten index, zeleny index, and falling number showed on average no significant difference between treatments although the protein composition was slightly different. The main results of this study are that the effect of reduced tillage on grain yield depends very much on soil type, weather conditions, and time after conversion, whereas there is only minor impact on wheat quality. This is in contrast to the hypothesis that reduced tillage under organic farming will cause problems in baking quality

Améliorer la qualité technologique, nutritionnelle et sanitaire du bléiologique. Principaux leviers agronomiques et technologiques

Communication lors du colloque "DinABio 2013", 13 et 14 novembre 2013 à Tours (Fance)The organic bread wheat market has been diversified over time through the emergence of different sale channels. Processors require organic bread wheat of higher quality and safety in order to meet the consumers’ demand. The overall objective of the AGTEC-Org project was to identify agronomical and technological ways to improve the performance of organic wheat and flour. The findings would contribute to enhanced baking quality and nutritional value of organic flour, as well as prevention of mycotoxin contamination. The project involved 9 research centers or universities from 5 European countries for a total budget of about 1.5 million €. More than 400 experimental treatments were analyzed from 23 agronomic trials and 4 lab-experiments on food technology. Choice of cultivar is an efficient way to obtain higher grain quality. Intercropping legumes (grain or forage) improves weed control and N availability for wheat crop or succeeding crop. Green manure can be an effective alternative to farmyard manure. Fertilization with organic fertilizers improves yield and quality when water is available. Reduced tillage affects soil fertility and wheat yield but has little effects on grain quality. Milling process strongly influences flour characteristics. Stone milling improves the nutritive value and flour characteristics remain very stable independently of the milling yield. However, stone milling slightly raises DON levels. Characteristics of flour produced by means of roller milling appear very dependent on milling yield, instead. Increasing milling yield with the aim of enriching nutritional quality has a detrimental effect on either safety (DON) or bread-making quality (bread volume). Debranning before milling has a very positive impact on flour safety by reducing its DON content by 50 %.Les acteurs de la filière blé biologique panifiable font face à divers enjeux complémentaires voire parfois contradictoires. Les agriculteurs et transformateurs souhaitent augmenter les niveaux de production tout en satisfaisant prioritairement les attentes des consommateurs pour une alimentation de meilleure qualité nutritionnelle et sanitaire, plus durable et plus respectueuse de l’environnement. Le projet européen AGTEC-Org a eu pour objectif d’identifier les leviers agronomiques et technologiques permettant d’améliorer conjointement la productivité et la qualité des blés et des farines biologiques. Il a réuni agronomes, technologues et économistes issus de 9 centres de recherche et universités européennes pour un budget total de 1,5 M€. Plus de 400 traitements expérimentaux ont été analysés à partir de 23 expérimentations agronomiques et 4 expérimentations technologiques. Le choix de la variété est un moyen efficace pour obtenir une qualité de grain supérieure. L’insertion de légumineuses (grain ou fourrage) dans le blé améliore la compétition avec les adventices et la nutrition azotée du blé et/ou de la culture de printemps suivante. L’utilisation régulière d’engrais vert peut être une alternative pour compenser l’absence de fumiers sur l’exploitation. La fertilisation organique améliore le rendement et la qualité des blés lorsque la nutrition hydrique est assurée. La suppression du labour peut affecter la fertilité du sol et le rendement du blé alors qu’elle n’intervient pas sur la qualité du grain. Le mode de broyage (meule de pierre vs cylindres) influence fortement les caractéristiques technologiques, la sécurité sanitaire et la valeur nutritionnelle de la farine. Le broyage sur meule améliore la composition nutritionnelle mais augmente aussi la présence de certains contaminants. Les caractéristiques de la farine broyée sur meule de pierre sont moins influencées par le rendement en mouture. Au contraire, les caractéristiques de la farine obtenue par cylindre apparaissent très dépendantes du rendement en mouture. Augmenter le rendement en farine dans l’objectif d’enrichir la qualité nutritionnelle réduit aussi bien la sécurité sanitaire (DON) que la qualité boulangère (volume du pain). Le décorticage des grains avant broyage diminue les risques sanitaires en réduisant le taux de mycotoxines (DON) de 50%

Improving baking quality, nutritional value and safety of organic winter wheat / Améliorer la qualité technologique, nutritionnelle et sanitaire du blé biologique, Principaux leviers agronomiques et technologiques

The organic bread wheat market has been diversified over time through the emergence of different sale channels. Processors require organic bread wheat of higher quality and safety in order to meet the consumers’ demand. The overall objective of the AGTEC-Org project was to identify agronomical and technological ways to improve the performance of organic wheat and flour. The findings would contribute to enhanced baking quality and nutritional value of organic flour, as well as prevention of mycotoxin contamination. The project involved 9 research centers or universities from 5 European countries for a total budget of about 1.5 million €. More than 400 experimental treatments were analyzed from 23 agronomic trials and 4 lab-experiments on food technology. Choice of cultivar is an efficient way to obtain higher grain quality. Intercropping legumes (grain or forage) improves weed control and N availability for wheat crop or succeeding crop. Green manure can be an effective alternative to farmyard manure. Fertilization with organic fertilizers improves yield and quality when water is available. Reduced tillage affects soil fertility and wheat yield but has little effects on grain quality. Milling process strongly influences flour characteristics. Stone milling improves the nutritive value and flour characteristics remain very stable independently of the milling yield. However, stone milling slightly raises DON levels. Characteristics of flour produced by means of roller milling appear very dependent on milling yield, instead. Increasing milling yield with the aim of enriching nutritional quality has a detrimental effect on either safety (DON) or bread-making quality (bread volume). Debranning before milling has a very positive impact on flour safety by reducing its DON content by 50 %

Neuromuscular Blockade with Rocuronium Bromide Increases the Tolerance of Acute Normovolemic Anemia in Anesthetized Pigs

Background: The patient's individual anemia tolerance is pivotal when blood transfusions become necessary, but are not feasible for some reason. To date, the effects of neuromuscular blockade (NMB) on anemia tolerance have not been investigated. Methods: 14 anesthetized and mechanically ventilated pigs were randomly assigned to the Roc group (3.78 mg/kg rocuronium bromide followed by continuous infusion of 1 mg/kg/min, n = 7) or to the Sal group (administration of the corresponding volume of normal saline, n = 7). Subsequently, acute normovolemic anemia was induced by simultaneous exchange of whole blood for a 6% hydroxyethyl starch solution (130/0.4) until a sudden decrease of total body O-2 consumption (VO2) indicated a critical limitation of O-2 transport capacity. The Hb concentration quantified at this time point (Hb(crit)) was the primary end-point of the protocol. Secondary endpoints were parameters of hemodynamics, O-2 transport and tissue oxygenation. Results: Hb(crit) was significantly lower in the Roc group (2.4 +/- 0.5 vs. 3.2 +/- 0.7 g/dl) reflecting increased anemia tolerance. NMB with rocuronium bromide reduced skeletal muscular VO2 and total body O-2 extraction rate. As the cardiac index increased simultaneously, total body VO2 only decreased marginally in the Roc group (change of VO2 relative to baseline -1.7 +/- 0.8 vs. 3.2 +/- 1.9% in the Sal group, p < 0.05). Conclusion: Deep NMB with rocuronium bromide increases the tolerance of acute normovolemic anemia. The underlying mechanism most likely involves a reduction of skeletal muscular VO2. During acellular treatment of an acute blood loss, NMB might play an adjuvant role in situations where profound stages of normovolemic anemia have to be tolerated (e.g. bridging an unexpected blood loss until blood products become available for transfusion). Copyright (C) 2011 S. Karger AG, Base

Larval fish dispersal in a coral-reef seascape

Free to read at publisher's site. Larval dispersal is a critical yet enigmatic process in the persistence and productivity of marine metapopulations. Empirical data on larval dispersal remain scarce, hindering the use of spatial management tools in efforts to sustain ocean biodiversity and fisheries. Here we document dispersal among subpopulations of clownfish (Amphiprion percula) and butterflyfish (Chaetodon vagabundus) from eight sites across a large seascape (10,000 km(2)) in Papua New Guinea across 2 years. Dispersal of clownfish was consistent between years, with mean observed dispersal distances of 15 km and 10 km in 2009 and 2011, respectively. A Laplacian statistical distribution (the dispersal kernel) predicted a mean dispersal distance of 13-19 km, with 90% of settlement occurring within 31-43 km. Mean dispersal distances were considerably greater (43-64 km) for butterfly-fish, with kernels declining only gradually from spawning locations. We demonstrate that dispersal can be measured on spatial scales sufficient to inform the design of and test the performance of marine reserve networks