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排序方式： 共有2029条查询结果，搜索用时 15 毫秒
991.
Rachel Mather Andrew Chin Cassandra Rigby Steven J. Cooke Fahmi Alifa Bintha Haque Meira Mizrahi Michael I. Grant 《水产资源保护:海洋与淡水生态系统》2024,34(1):e4039
- Globally, freshwater environments are imperilled, with freshwater vertebrate species declining at twice the rate of marine and terrestrial populations. Non-marine elasmobranchs (freshwater obligates and euryhaline generalists) remain understudied and overlooked by conservation efforts.
- This study aimed to adapt and apply a vulnerability assessment framework to understand the conservation priorities of Indo-West Pacific non-marine elasmobranch species. An exposure sensitivity adaptability (ESA) framework was used to assess vulnerability to environmental threats, and an exposure susceptibility productivity (ESP) framework was used to assess vulnerability to fisheries.
- Resulting species vulnerabilities were categorized into three conservation priority tiers. The general patterns of conservation priority tiering were as follows: (i) large-bodied euryhaline species occurring in densely populated nations had the highest ESA and ESP vulnerabilities; (ii) freshwater obligates also had high ESA vulnerability rankings, although ESP vulnerability rankings were lower as their smaller body sizes suggest increased population productivity and higher potential for resilience; and (iii) euryhaline species with large range proportions in northern Australia had moderate to low vulnerability rankings across ESA and ESP assessments, as these species benefit from reduced fisheries mortality compared with species occurring in other regions.
- The outcomes from the vulnerability assessment framework for the conservation priority rankings of species corresponded with their respective International Union for Conservation of Nature (IUCN) Red List status, whereby priority 1 and 2 species also have elevated extinction risks. Environmental threats were at high or moderate levels in all nations assessed, while Cambodia, China, Malaysia, and Myanmar face the highest pressure from inland fisheries.
- The major knowledge gaps identified included species-specific productivity estimates, population dynamics (population movements and habitat requirements), and information on mortality from the threats considered. The present ESA–ESP framework was effective for the broad and data-poor context of Indo-West Pacific non-marine elasmobranchs, and the results will be useful for guiding future conservation planning for high-priority species and nations.
992.
Ashley M. Fowler Natalie A. Dowling Jeremy M. Lyle Josep Alós Leif E. Anderson Steven J. Cooke Andy J. Danylchuk Keno Ferter Heath Folpp Clifford Hutt Kieran Hyder Daniel K. Lew Michael B. Lowry Tim P. Lynch Nicholas Meadows Estanis Mugerza Kjell Nedreaas Domingos Garrone-Neto Faith A. Ochwada-Doyle Warren Potts David Records Scott Steinback Harry V. Strehlow Sean R. Tracey Michael D. Travis Jun-ichi Tsuboi Jon Helge Vølstad Rowan C. Chick 《Fish and Fisheries》2023,24(6):1003-1019
Recreational fishing (RF) is a large yet undervalued component of fisheries globally. While progress has been made in monitoring, assessing, and managing the sector in isolation, integration of RF into the management of multi-sector fisheries has been limited, particularly relative to the commercial sector. This marginalises recreational fishers and reduces the likelihood of achieving the sector's objectives and, more broadly, achieving fisheries sustainability. We examined the nature and extent of RF inclusion in harvest strategies (HSs) for marine fisheries across 15 regions in 11 nations to define the gap in inclusion that has developed between sectors. We focused on high-income nations with a high level of RF governance and used a questionnaire to elicit expert knowledge on HSs due to the paucity of published documents. In total, 339 HSs were considered. We found that RF inclusion in HSs was more similar to the small-scale sector (i.e., artisanal, cultural, or subsistence) than the commercial sector, with explicit operational objectives, data collection, performance indicators, reference points, and management controls lacking in many regions. Where specified, RF objectives focused on sustainability, economic value and catch allocation rather than directly relating to the recreational fishing experience. Conflicts with other sectors included competition with the commercial sector for limited resources, highlighting the importance of equitable resource allocation policies alongside HSs. We propose that RF be explicitly incorporated into HSs to ensure fisheries are ecologically, economically, and socially sustainable, and we recommend that fisheries organisations urgently review HSs for marine fisheries with a recreational component to close the harvest strategy gap among sectors. 相似文献
993.
Steven J. Bograd Martin Edwards Shin-ichi Ito Janet Nye Emily Chappell 《Fisheries Oceanography》2023,32(1):3-9
The journal Fisheries Oceanography provides a global forum for fisheries scientists and oceanographers to understand how marine ecosystems, and the services they provide to society, are structured and shaped by environmental variability and climate change. With this special issue, as well as the 30th Anniversary Virtual Issue of the most influential papers from the journal's history, we commemorate 30 years of publishing leading research in the field of fisheries oceanography. These issues showcase the extent, depth and impact of the research published in Fisheries Oceanography. We also reflect on the evolution of research themes through the journal's history, and highlight key emergent themes in our field. We look forward to continuing to publish impactful research in the pages of Fisheries Oceanography in the years ahead. 相似文献
994.
Nima Farchadi;Heather Welch;Camrin D. Braun;Andrew J. Allyn;Steven J. Bograd;Stephanie Brodie;Elliott L. Hazen;Alex Kerney;Nerea Lezama-Ochoa;Katherine E. Mills;Dylan Pugh;Riley Young-Morse;Rebecca L. Lewison; 《Fish and Fisheries》2024,25(4):602-618
Marine heatwaves (MHWs) have measurable impacts on marine ecosystems and reliant fisheries and associated communities. However, how MHWs translate to changes in fishing opportunities and the displacement of fishing fleets remains poorly understood. Using fishing vessel tracking data from the automatic identification system (AIS), we developed vessel distribution models for two pelagic fisheries targeting highly migratory species, the U.S. Atlantic longline and Pacific troll fleets, to understand how MHW properties (intensity, size, and duration) influence core fishing grounds and fleet displacement. For both fleets, MHW size had the largest influence on fishing ground area with northern fishing grounds gaining and southern fishing grounds decreasing in area. However, fleet displacement in response to MHWs varied between coasts, as the Atlantic longline fleet displaced farther in southern regions whereas the most northern and southern regions of the Pacific troll fleet shifted farther. Characterizing fishing fleet responses to these anomalous conditions can help identify regional vulnerabilities under future extreme events and aid in supporting climate-readiness and resilience in pelagic fisheries. 相似文献
995.
996.
From whence will they come? - A perspective on the acute shortage of pathologists in biomedical research. 总被引：1，自引：0，他引：1
997.
Frana TS Carlson SA Rauser DC Jones BD Fergen BJ Griffith RW 《American journal of veterinary research》2004,65(12):1616-1620
OBJECTIVE: To investigate the effect of an Escherichia that produced microcin 24 (Mcc24) on shedding of of Salmonella enterica serotypeTyphimurium in swine and evaluate evidence of in vivo activation of the Mcc24-mediated, multiple-antibiotic resistance (mar) operon. ANIMALS: 36 crossbred weaned pigs. PROCEDURE: 24 pigs were allocated to 2 groups (12 pigs/group). Pigs in 1 group received daily oral administration of an Mcc24-producing E coli, whereas the other group received a non-Mcc24-producing E coli. All pigs were challenge exposed with Salmonella Typhimurium chi4232. A third group of 6 pigs received Mcc24-producing E coli and was challenge exposed with an Mcc24-sensitive, marA-deleted strain of Salmonella Typhimurium 4232. After challenge exposure, fecal samples from all pigs were cultured to detect shedding of Salmonella Typhimurium and Salmonella Typhimurium isolates were screened for resistance to ciprofloxacin. Fecal samples were collected throughout the study, and tissue samples were collected during necropsy. RESULTS: Differences in shedding of Salmonella Typhimurium were not detected between groups receiving Mcc24-producing or non-Mcc24-producing E coli. No significant differences were found in quantitative analysis between groups receiving Mcc24-producing and non-Mcc24-producing E coli. Evidence of mar activation was not detected. CONCLUSIONS AND CLINICAL RELEVANCE: Microcin-producing E coli did not exert an effect on shedding of SalmonellaTyphimurium or mar activation in pigs. It may be difficult or impractical to create the conditions required for Mcc24 to be an effective part of a food safety intervention to reduce shedding of Salmonella Typhimurium. 相似文献
998.
Mark Caulfield Jeroen C. J. Groot Steven J. Fonte Stephen Sherwood Pedro Oyarzun Ross Mary Borja Sam Dumble Pablo Tittonell 《Land Degradation u0026amp; Development》2020,31(13):1650-1661
Land degradation caused by erosion and nutrient depletion in the Andes poses serious existential threats to small‐scale farming. Although the potential of hedgerows to decrease water erosion is well recognised, their potential dual‐use as a source of organic amendments to supplement farmer inputs is much less studied. The objective of this investigation was therefore to explore locally developed options for hedgerows that address these twin challenges. Experimental plots were installed to assess water erosion control by hedgerows and the effect of organic amendments harvested from the hedgerows on soil productivity, soil moisture, and soil fertility over the course of 2 years and three crop cycles (two of barley and one of rye). The experiment was conducted in two sites within the community at distinct elevations and associated biophysical contexts. At each site, four treatments were established, comparing a control treatment versus three types of hedgerows: (a) Andean alder, (b) canary grass strips, and (c) mixed canary grass and Andean alder. Results demonstrated that hedgerows and associated organic inputs comprised canary grass, and mixed canary grass and Andean alder reduced water erosion by 50–60% and increased biomass production by up to 1.1 Mg ha−1 and grain yield by up to 0.5 Mg ha−1. We conclude that although hedgerows are unlikely to produce sufficient quantities of organic resources to satisfy all nutrient input requirements, their potential to decrease erosion and supplement existing organic matter inputs indicates that they should be strongly considered as an option for improved agricultural management within this and similar resource constrained contexts. 相似文献
999.
1000.