30 research outputs found

    Predicting global invasion risks: a management tool to prevent future introductions

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    Predicting regions at risk from introductions of non-native species and the subsequent invasions is a fundamental aspect of horizon scanning activities that enable the development of more effective preventative actions and planning of management measures. The Asian cyprinid fish topmouth gudgeon Pseudorasbora parva has proved highly invasive across Europe since its introduction in the 1960s. In addition to direct negative impacts on native fish populations, P. parva has potential for further damage through transmission of an emergent infectious disease, known to cause mortality in other species. To quantify its invasion risk, in regions where it has yet to be introduced, we trained 900 ecological niche models and constructed an Ensemble Model predicting suitability, then integrated a proxy for introduction likelihood. This revealed high potential for P. parva to invade regions well beyond its current invasive range. These included areas in all modelled continents, with several hotspots of climatic suitability and risk of introduction. We believe that these methods are easily adapted for a variety of other invasive species and that such risk maps could be used by policy-makers and managers in hotspots to formulate increased surveillance and early-warning systems that aim to prevent introductions and subsequent invasions

    Benthic community structure and ecosystem functions in above- and below-waterfall pools in Borneo

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    Waterfalls are geomorphic features that often partition streams into discrete zones. Our study examined aquatic communities, litter decomposition and periphyton growth rates for above- and below-waterfall pools in Ulu Temburong National Park, Brunei. We observed higher fish densities in below-waterfall pools (0.24 fish m−2 vs. 0.02 fish m−2 in above-waterfall pools) and higher shrimp abundance in above-waterfall pools (eight shrimp/pool vs. less than one shrimp/pool in below-waterfall pools). However, macroinvertebrate densities (excluding shrimp) were similar among both pool types. Ambient periphyton was higher in below-waterfall pools in 2013 (4.3 vs. 2.8 g m−2 in above-waterfall pools) and 2014 (4.8 vs. 3.4 g m−2 in above-waterfall pools), while periphyton growth rates varied from 0.05 to 0.26 g m−2 days−1 and were significantly higher in below-waterfall pools in 2014. Leaf litter decomposition rates (0.001 to 0.024 days−1) did not differ between pool types, suggesting that neither shrimp nor fish densities had consistent impacts on this ecosystem function. Regardless, this research demonstrates the varied effects of biotic and abiotic factors on community structure and ecosystem function. Our results have highlighted the importance of discontinuities, such as waterfalls, in tropical streams.</p

    Towards more efficient longline fisheries: fish feeding behaviour, bait characteristics and development of alternative baits

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    How Do They Do It? – Understanding the Success of Marine Invasive Species

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    From the depths of the oceans to the shallow estuaries and wetlands of our coasts, organisms of the marine environment are teeming with unique adaptations to cope with a multitude of varying environmental conditions. With millions of years and a vast volume of water to call their home, they have become quite adept at developing specialized and unique techniques for survival and – given increasing human mediated transport – biological invasions. A growing world human population and a global economy drives the transportation of goods across the oceans and with them invasive species via ballast water and attached to ship hulls. In any given 24-hour period, there are about 10,000 species being transported across different biogeographic regions. If any of them manage to take hold and establish a range in an exotic habitat, the implications for local ecosystems can be costly. This review on marine invasions highlights trends among successful non-indigenous species (NIS), from vectors of transport to ecological and physiological plasticity. Apart from summarizing patterns of successful invasions, it discusses the implications of how successfully established NIS impact the local environment, economy and human health. Finally, it looks to the future and discusses what questions need to be addressed and what models can tell us about what the outlook on future marine invasions is

    Prognostic role of lactate on mortality in younger and older patients with cardio-respiratory failure admitted to an acute intensive care unit

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    BACKGROUND AND AIM: Acidosis is able to induce negative changes of different organs that increase progressively with aging. At present it is not known whether the levels of lactate may differently influence the prognosis of younger and older patients. Thus, the aim of this study is to evaluate the prognostic value of lactate levels after admission of younger and older patients to an acute intensive care unit. METHODS: Younger (<65 years, n = 118) and older (≥65 years, n = 165) patients admitted to an acute intensive care unit were prospectively enrolled and classified according to diagnosis of acute heart or/and respiratory failure. For each patient, APACHE II score, time of hospitalization and mortality, blood levels of lactate were collected. RESULTS: Both in-hospital mortality and lactate >2.5 mmol/L at the admission was higher in the older than in the younger patients (42.4 vs. 20.3 %, p < 0.01 and 57.8 vs. 31.9 %, p < 0.01, respectively). Lactate level was higher in older than in the younger patients both at admission and after 24 h (3.9 ± 3.4 vs. 2.4 ± 2.2 mmol/L and 2.4 ± 2.0 vs. 1.4 ± 1.3 mmol, p < 0.01, respectively). Accordingly, multivariate analysis shows that lactate was predictive of mortality in younger (OR = 2.65, 95 % CI 1.62-5.24, p = 0.03) and even more in the older (OR = 4.74, 95 % CI 2.10-6.70, p < 0.01) patients. CONCLUSIONS: Lactate concentration increase is associated with increased mortality in younger patients but, even more so, in older patients admitted to an acute intensive care unit. These results confirm the experimental evidence showing acidosis has a greater effect of leading to organ failure and higher mortality with increasing age
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