Sample records for cod fisheries selectivity
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Svedäng, Henrik; Hornborg, Sara
2017-08-01
Understanding how combinations of fishing effort and selectivity affect productivity is central to fisheries research. We investigate the roles of fishing regulation in comparison with ecosystem status for Baltic Sea cod stock productivity, growth performance, and population stability. This case study is interesting because three cod populations with different exploitation patterns and stock status are located in three adjacent but partially, ecologically different areas. In assessing stock status, growth, and productivity, we use survey information and rather basic stock parameters without relying on age readings. Because there is an urgent interest of better understanding of the current development of the Eastern Baltic cod stock, we argue that our approach represents partly a novel way of interpreting monitoring information together with catch data in a simplified yet more informative way. Our study reports how the Eastern and Western Baltic cod have gone toward more truncated size structures between 1991 and 2016, in particular for the Eastern Baltic cod, whereas the Öresund cod show no trend. We suggest that selective fishing may disrupt fish population dynamic stability and that lower natural productivity might amplify the effects of selective fishing. In support of earlier findings on a density-dependent growth of Eastern Baltic cod, management is advised to acknowledge that sustainable exploitation levels for Eastern Baltic cod are much more limited than perceived in regular assessments. Of more general importance, our results emphasize the need to embrace a more realistic view on what ecosystems can produce regarding tractable fish biomass to facilitate a more ecosystem-based fisheries management.
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Federal Register 2010, 2011, 2012, 2013, 2014
2011-06-28
...-AY53 Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod Allocations in the Gulf of Alaska... the uncertainty regarding the distribution of Pacific cod catch, enhance stability among the sectors... available for public review and comment. The groundfish fisheries in the exclusive economic zone of the Gulf...
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Federal Register 2010, 2011, 2012, 2013, 2014
2010-11-15
.... 0910131363-0087-02] RIN 0648-XA038 Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod in the Bering Sea and Aleutian Islands Management Area AGENCY: National Marine Fisheries Service (NMFS...: NMFS is prohibiting retention of Pacific cod in the Bering Sea and Aleutian Islands Management Area...
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Federal Register 2010, 2011, 2012, 2013, 2014
2011-11-29
... miles of shore adjacent to the Bering Sea and Aleutian Islands management area (BSAI). The affected... Cod Fishing in the Parallel Fishery in the Bering Sea and Aleutian Islands Management Area AGENCY... limits access by Federally permitted vessels to the parallel fishery for Pacific cod in three ways. First...
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Federal Register 2010, 2011, 2012, 2013, 2014
2012-06-12
... in the BSAI exclusive economic zone according to the Fishery Management Plan for Groundfish of the.... 111213751-2102-02] RIN 0648-XC064 Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod for... Management Area AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and Atmospheric...
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Jakobsdóttir, Klara B; Pardoe, Heidi; Magnússon, Árni; Björnsson, Höskuldur; Pampoulie, Christophe; Ruzzante, Daniel E; Marteinsdóttir, Guðrún
2011-01-01
The intense fishing mortality imposed on Atlantic cod in Icelandic waters during recent decades has resulted in marked changes in stock abundance, as well as in age and size composition. Using a molecular marker known to be under selection (Pan I) along with a suite of six neutral microsatellite loci, we analysed an archived data set and revealed evidence of distinct temporal changes in the frequencies of genotypes at the Pan I locus among spawning Icelandic cod, collected between 1948 and 2002, a period characterized by high fishing pressure. Concurrently, temporal stability in the composition of the microsatellite loci was established within the same data set. The frequency of the Pan IBB genotype decreased over a period of six decades, concomitant with considerable spatial and technical changes in fishing effort that resulted in the disappearance of older individuals from the fishable stock. Consequently, these changes have likely led to a change in the genotype frequencies at this locus in the spawning stock of Icelandic cod. The study highlights the value of molecular genetic approaches that combine functional and neutral markers examined in the same set of individuals for investigations of the selective effects of harvesting and reiterates the need for an evolutionary dimension to fisheries management. PMID:25568005
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50 CFR Table 5 to Part 679 - Steller Sea Lion Protection Areas Pacific Cod Fisheries Restrictions
Code of Federal Regulations, 2010 CFR
2010-10-01
... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false Steller Sea Lion Protection Areas Pacific Cod Fisheries Restrictions 5 Table 5 to Part 679 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE (CONTINUED) FISHERIES OF THE EXCLUSIVE ECONOMIC ZONE OFF ALASKA Pt....
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50 CFR Table 5 to Part 679 - Steller Sea Lion Protection Areas Pacific Cod Fisheries Restrictions
Code of Federal Regulations, 2011 CFR
2011-10-01
... 50 Wildlife and Fisheries 11 2011-10-01 2011-10-01 false Steller Sea Lion Protection Areas Pacific Cod Fisheries Restrictions 5 Table 5 to Part 679 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE (CONTINUED) FISHERIES OF THE EXCLUSIVE ECONOMIC ZONE OFF ALASKA Pt....
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50 CFR Table 5 to Part 679 - Steller Sea Lion Protection Areas Pacific Cod Fisheries Restrictions
Code of Federal Regulations, 2014 CFR
2014-10-01
... 50 Wildlife and Fisheries 13 2014-10-01 2014-10-01 false Steller Sea Lion Protection Areas Pacific Cod Fisheries Restrictions 5 Table 5 to Part 679 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE (CONTINUED) FISHERIES OF THE EXCLUSIVE ECONOMIC ZONE OFF ALASKA Pt....
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50 CFR Table 5 to Part 679 - Steller Sea Lion Protection Areas Pacific Cod Fisheries Restrictions
Code of Federal Regulations, 2012 CFR
2012-10-01
... 50 Wildlife and Fisheries 13 2012-10-01 2012-10-01 false Steller Sea Lion Protection Areas Pacific Cod Fisheries Restrictions 5 Table 5 to Part 679 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE (CONTINUED) FISHERIES OF THE EXCLUSIVE ECONOMIC ZONE OFF ALASKA Pt....
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50 CFR Table 5 to Part 679 - Steller Sea Lion Protection Areas Pacific Cod Fisheries Restrictions
Code of Federal Regulations, 2013 CFR
2013-10-01
... 50 Wildlife and Fisheries 13 2013-10-01 2013-10-01 false Steller Sea Lion Protection Areas Pacific Cod Fisheries Restrictions 5 Table 5 to Part 679 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE (CONTINUED) FISHERIES OF THE EXCLUSIVE ECONOMIC ZONE OFF ALASKA Pt....
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Federal Register 2010, 2011, 2012, 2013, 2014
2010-01-25
.... 0810141351-9087-02] RIN 0648-XT95 Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Vessels Participating in the Amendment 80 Limited Access Fishery in Bering Sea and Aleutian Islands Management Area... management area (BSAI). This action is necessary to prevent exceeding the 2010 Pacific cod total allowable...
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Federal Register 2010, 2011, 2012, 2013, 2014
2011-08-30
... Fishery; Trip Limit Decrease for the Common Pool Fishery AGENCY: National Marine Fisheries Service (NMFS... (GB) cod for Northeast (NE) multispecies common pool vessels for the 2011 fishing year (FY), through... reduce the harvest of GOM and GB cod to prevent the common pool sub-annual catch limit (sub-ACL) from...
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Federal Register 2010, 2011, 2012, 2013, 2014
2011-10-03
... Fishery; Correction to Cod Landing Limit for Handgear B Vessels in the Common Pool Fishery AGENCY... multispecies open access Handgear B permitted vessels fishing in the common pool fishery for the remainder of... landing limits for Handgear B (HB) vessels fishing under common pool regulations at Sec. 648.88(a)(1...
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Khan, Ahmed; Chuenpagdee, Ratana
2014-09-01
Rebuilding collapsed fisheries is a multifaceted problem, requiring a holistic governance approach rather than technical management fixes. Using the Northern Gulf cod case study in eastern Canada, we illustrate how a "fish chain" framework, drawn from the interactive governance perspective, is particularly helpful in analyzing rebuilding challenges. The analysis demonstrates that factors limiting rebuilding exist along the entire fish chain, i.e., the pre-harvest, harvest, and post-harvest stages. These challenges are embedded in both the ecological and social systems associated with the Northern Gulf cod fisheries, as well as in the governing systems. A comparative analysis of the pre- and post-collapse of the cod fisheries also reveals governance opportunities in rebuilding, which lie in policy interventions such as integrated and ecosystem-based management, livelihood transitional programs, and cross-scale institutional arrangements. Lessons from the Northern Gulf cod case study, especially the missed opportunities to explore alternative governing options during the transition, are valuable for rebuilding other collapsed fisheries.
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Federal Register 2010, 2011, 2012, 2013, 2014
2010-06-04
... DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration 50 CFR Part 679 [Docket No. 0910131363-0087-02] RIN 0648-XW75 Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod for American Fisheries Act Catcher Processors Using Trawl Gear in the Bering Sea and Aleutian Islands...
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Federal Register 2010, 2011, 2012, 2013, 2014
2010-02-23
... DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration 50 CFR Part 679 [Docket No. 0810141351-9087-02] RIN 0648-XU52 Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod for American Fisheries Act Catcher-Processors Using Trawl Gear in the Bering Sea and Aleutian Islands...
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Federal Register 2010, 2011, 2012, 2013, 2014
2011-08-04
... DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration 50 CFR Part 679 [Docket No. 101126521-0640-2] RIN 0648-XA616 Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod for American Fisheries Act Catcher/Processors Using Trawl Gear in the Bering Sea and Aleutian Islands...
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Federal Register 2010, 2011, 2012, 2013, 2014
2012-02-23
... DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration 50 CFR Part 679 [Docket No. 101126521-0640-02] RIN 0648-XB028 Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod for American Fisheries Act Catcher/Processors Using Trawl Gear in the Bering Sea and Aleutian Islands...
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Federal Register 2010, 2011, 2012, 2013, 2014
2010-04-06
... DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration 50 CFR Part 679 [Docket No. 0910131363-0087-02] RIN 0648-XV66 Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod for American Fisheries Act Catcher Processors Using Trawl Gear in the Bering Sea and Aleutian Islands...
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Federal Register 2010, 2011, 2012, 2013, 2014
2012-03-30
... DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration 50 CFR Part 679 [Docket No. 111213751-2102-02] RIN 0648-XB138 Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod for American Fisheries Act Catcher/Processors Using Trawl Gear in the Bering Sea and Aleutian Islands...
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Federal Register 2010, 2011, 2012, 2013, 2014
2011-03-14
... who also had significant participation in, or dependence on, the GOA Pacific cod fishery to maintain... vessels that demonstrated minimal participation in, or dependence on, the Bering Sea snow crab fishery and sufficient participation in, or dependence on, the GOA Pacific cod fishery from 1996 through 2000. Non-AFA...
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Orton, David C.; Makowiecki, Daniel; de Roo, Tessa; Johnstone, Cluny; Harland, Jennifer; Jonsson, Leif; Heinrich, Dirk; Enghoff, Inge Bødker; Lõugas, Lembi; Van Neer, Wim; Ervynck, Anton; Hufthammer, Anne Karin; Amundsen, Colin; Jones, Andrew K. G.; Locker, Alison; Hamilton-Dyer, Sheila; Pope, Peter; MacKenzie, Brian R.; Richards, Michael; O'Connell, Tamsin C.; Barrett, James H.
2011-01-01
Although recent historical ecology studies have extended quantitative knowledge of eastern Baltic cod (Gadus morhua) exploitation back as far as the 16th century, the historical origin of the modern fishery remains obscure. Widespread archaeological evidence for cod consumption around the eastern Baltic littoral emerges around the 13th century, three centuries before systematic documentation, but it is not clear whether this represents (1) development of a substantial eastern Baltic cod fishery, or (2) large-scale importation of preserved cod from elsewhere. To distinguish between these hypotheses we use stable carbon and nitrogen isotope analysis to determine likely catch regions of 74 cod vertebrae and cleithra from 19 Baltic archaeological sites dated from the 8th to the 16th centuries. δ13C and δ15N signatures for six possible catch regions were established using a larger sample of archaeological cod cranial bones (n = 249). The data strongly support the second hypothesis, revealing widespread importation of cod during the 13th to 14th centuries, most of it probably from Arctic Norway. By the 15th century, however, eastern Baltic cod dominate within our sample, indicating the development of a substantial late medieval fishery. Potential human impact on cod stocks in the eastern Baltic must thus be taken into account for at least the last 600 years. PMID:22110675
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Federal Register 2010, 2011, 2012, 2013, 2014
2010-10-21
...; Correction to Cod Landing Limit for Handgear A Vessels in the Common Pool Fishery AGENCY: National Marine... multispecies limited access Handgear A (HA) permitted vessels fishing in the common pool fishery for the... vessels fishing under common pool regulations at Sec. 648.82(b)(6) state that ``The [300 lb (136.1 kg...
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NASA Astrophysics Data System (ADS)
Adlerstein, Sara A.; Trumble, Robert J.
1998-03-01
Mortality of discarded Pacific halibut bycatch from Pacific cod fisheries in the Bering Sea leads to significant losses in the halibut setline and in the Pacific cod fisheries. The commercial halibut fishery loses yield because of catch limit reductions to compensate the resource for lost spawning potential and because halibut killed as bycatch will not be available for subsequent harvest, and the cod fisheries may lose harvest if they reach a bycatch mortality limit before reaching allowed catch. In this study, significant differences in Pacific halibut bycatch rates and associated yield losses were found among months and areas of the Bering Sea in the longline and trawl fisheries for Pacific cod in 1990-1992. Bycatch rates were usually highest in late spring and early summer and in areas close to the Unimak Pass. With the exception of 1992, yield loss in the longline fishery was around 1 kg per kg of bycatch mortality, irrespective of where or when bycatch occurred. In the trawl fishery, loss of halibut yield varied from 1 to 4 kg per kg of bycatch mortality. Highest halibut net yield losses per tonne of groundfish harvest usually coincided with highest bycatch rates. When both fisheries operated in one area, trawl bycatch often imposed higher yield losses than longline bycatch, despite lower bycatch rates. Bycatch was affected by the strong 1987 halibut year class. Highest bycatch and yield loss rates occurred in the trawl fishery in 1990 and 1991 when the population was dominated by halibut age-3 and -4, and in the longline fishery in 1992 as fish reached age-5.
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Federal Register 2010, 2011, 2012, 2013, 2014
2013-05-07
... that gillnet gear should not be included in the Western Exemption Area. The Eastern Cape Cod Spiny... dogfish permit to fish in an area east of Cape Cod, MA (Eastern Exemption Area) with gillnet and longline... Bay (Western Exemption Area) with longline gear and handgear from June through August. This action...
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Federal Register 2010, 2011, 2012, 2013, 2014
2010-09-14
.... 0910131363-0087-02] RIN 0648-XZ01 Fisheries of the Exclusive Economic Zone Off Alaska; Reallocation of Pacific cod in the Bering Sea and Aleutian Islands Management Area AGENCY: National Marine Fisheries... Sea and Aleutian Islands management area. These actions are necessary to allow the 2010 total...
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Federal Register 2010, 2011, 2012, 2013, 2014
2013-02-08
.... 111213751-2102-02] RIN 0648-XC481 Fisheries of the Exclusive Economic Zone Off Alaska; Reallocation of Pacific Cod in the Bering Sea and Aleutian Islands Management Area AGENCY: National Marine Fisheries... in the Bering Sea and Aleutian Islands management area. This action is necessary to allow the A...
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Federal Register 2010, 2011, 2012, 2013, 2014
2011-03-07
.... 101126521-0640-02] RIN 0648-XA260 Fisheries of the Exclusive Economic Zone Off Alaska; Reallocation of Pacific Cod in the Bering Sea and Aleutian Islands Management Area AGENCY: National Marine Fisheries... in the Bering Sea and Aleutian Islands management area. This action is necessary to allow the A...
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ERIC Educational Resources Information Center
Ramsey, Doug
2002-01-01
Uses lyrics and musical styles to illustrate the role of music in educating young people about ecosystem fragility and the cultural importance of rural resources. Describes the east coast fishery prior to and following the announcement of the Northern Cod fishery moratorium in 1992. (Contains 40 references.) (Author/YDS)
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Federal Register 2010, 2011, 2012, 2013, 2014
2012-03-09
... Using Jig Gear in the Central Regulatory Area of the Gulf of Alaska AGENCY: National Marine Fisheries...; closure. SUMMARY: NMFS is prohibiting directed fishing for Pacific cod by vessels using jig gear in the... season allowance of the 2012 Pacific cod total allowable catch apportioned to vessels using jig gear in...
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Federal Register 2010, 2011, 2012, 2013, 2014
2012-02-09
... Using Pot Gear in the Western Regulatory Area of the Gulf of Alaska AGENCY: National Marine Fisheries...; closure. SUMMARY: NMFS is prohibiting directed fishing for Pacific cod by vessels using pot gear in the... season allowance of the 2012 Pacific cod total allowable catch apportioned to vessels using pot gear in...
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Federal Register 2010, 2011, 2012, 2013, 2014
2012-02-14
... Using Pot Gear in the Central Regulatory Area of the Gulf of Alaska AGENCY: National Marine Fisheries...; closure. SUMMARY: NMFS is prohibiting directed fishing for Pacific cod by vessels using pot gear in the... season allowance of the 2012 Pacific cod total allowable catch apportioned to vessels using pot gear in...
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Federal Register 2010, 2011, 2012, 2013, 2014
2012-09-06
.... 111207737-2141-02] RIN 0648-XC205 Fisheries of the Exclusive Economic Zone Off Alaska; Reallocation of Pacific Cod in the Western Regulatory Area of the Gulf of Alaska Management Area AGENCY: National Marine... Alaska management area. This action is necessary to allow the 2012 total allowable catch of Pacific cod...
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Federal Register 2010, 2011, 2012, 2013, 2014
2012-04-03
... will constrain catch to the recreational sub-ACL; and reduce overfishing occurring on GOM cod in...). This interim rule implements a total GOM cod total annual catch limit (ACL) of 6,700 mt and divides... implementing interim measures: Setting a total GOM cod ACL in a 6,700 to 7,500 mt range; Modifying the...
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Cod Collapse and the Climate in the North Atlantic
NASA Astrophysics Data System (ADS)
Meng, K. C.; Oremus, K. L.; Gaines, S.
2014-12-01
Effective fisheries management requires forecasting population changes. We find a negative relationship between the North Atlantic Oscillation (NAO) index and subsequently surveyed biomass and catch of Atlantic cod, Gadus morhua, off the New England coast. A 1-unit NAO increase is associated with a 17% decrease in surveyed biomass of age-1 cod the following year. This relationship persists as the cod mature, such that observed NAO can be used to forecast future adult biomass. We also document that an NAO event lowers catch for up to 15 years afterward. In contrast to forecasts by existing stock assessment models, our NAO-driven statistical model successfully hindcasts the recent collapse of New England cod fisheries following strong NAO events in 2007 and 2008 (see figure). This finding can serve as a template for forecasting other fisheries affected by climatic conditions.
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Federal Register 2010, 2011, 2012, 2013, 2014
2013-12-06
... in the Gulf of Alaska exclusive economic zone according to the Fishery Management Plan for Groundfish.... 120918468-3111-02] RIN 0648-XC976 Fisheries of the Exclusive Economic Zone Off Alaska; Reallocation of Pacific Cod in the Central Regulatory Area of the Gulf of Alaska Management Area AGENCY: National Marine...
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Federal Register 2010, 2011, 2012, 2013, 2014
2013-09-10
... in the Gulf of Alaska exclusive economic zone according to the Fishery Management Plan for Groundfish.... 120918468-3111-02] RIN 0648-XC856 Fisheries of the Exclusive Economic Zone Off Alaska; Reallocation of Pacific Cod in the Western Regulatory Area of the Gulf of Alaska Management Area AGENCY: National Marine...
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Federal Register 2010, 2011, 2012, 2013, 2014
2013-09-30
... authorizing a designated vessel to catch and process Pacific cod in the BSAI hook-and-line fisheries to use... (MLOA) to 220 feet (67 m) on LLP licenses authorizing vessels to catch and process Pacific cod with hook... cod with hook-and-line and pot gear in the BSAI to increase the MLOA on the LLP license to 220 feet...
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Federal Register 2010, 2011, 2012, 2013, 2014
2011-03-11
... Department of Fish and Game (ADF&G) through emergency order under the authority of State regulations at 5 AAC... Pacific cod among ten fishery sectors created in Amendment 67, to better reflect the historical dependency...
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Federal Register 2010, 2011, 2012, 2013, 2014
2012-10-19
.... 120905422-2521-01] RIN 0648-BC50 Fisheries of the Northeastern United States; Northeast Multispecies Fishery; Exempted Fishery for the Cape Cod Spiny Dogfish Fishery AGENCY: National Marine Fisheries Service (NMFS... Fishery Management Plan (FMP) to allow vessels to fish with gillnet and longline gear from June through...
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Cod Collapse and Climate in the North Atlantic
NASA Astrophysics Data System (ADS)
Oremus, K. L.; Meng, K. C.; Gaines, S.
2016-02-01
Understanding the determinants of fish population dynamics is crucial to the recovery of many fisheries. Current research emphasizes the role of environmental conditions in driving fish populations, but the magnitude of and mechanisms behind these effects on crucial populations are not well established. Despite aggressive management efforts, New England cod fisheries have been in decline for several decades and have now reached unprecedented lows. We find a strong negative relationship between the North Atlantic Oscillation (NAO) and subsequent adult cod biomass and catch. In the Gulf of Maine fishery, a 1-unit NAO increase is associated with a 13% decrease in the biomass of age-1 cod the following year, a decrease that persists as the affected cohort matures. We further detect that a 1-unit NAO increase can lower commercial catch for up to 19 subsequent years, suggesting that fishing practices may be inadvertently exacerbating NAO's direct biological effects. These results imply that 18% and 32% of the overall decline in adult biomass and catch, respectively, since 1980 can be attributed to the NAO's recent multi-decadal positive phase. The Georges Bank cod fishery displays similar patterns. Because there is a delay between an NAO event and subsequent declines in adult biomass, our finding implies that already observed NAO events can be used in stock forecasts, providing lead time for adaptive policy. More broadly, our approach can inform forecasting efforts for other fisheries strongly affected by natural and anthropogenic climatic variation.
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NASA Astrophysics Data System (ADS)
Lindstrøm, Ulf; Smout, Sophie; Howell, Daniel; Bogstad, Bjarte
2009-10-01
The Barents Sea ecosystem, one of the most productive and commercially important ecosystems in the world, has experienced major fluctuations in species abundance the past five decades. Likely causes are natural variability, climate change, overfishing and predator-prey interactions. In this study, we use an age-length structured multi-species model (Gadget, Globally applicable Area-Disaggregated General Ecosystem Toolbox) to analyse the historic population dynamics of major fish and marine mammal species in the Barents Sea. The model was used to examine possible effects of a number of plausible biological and fisheries scenarios. The results suggest that changes in cod mortality from fishing or cod cannibalism levels have the largest effect on the ecosystem, while changes to the capelin fishery have had only minor effects. Alternate whale migration scenarios had only a moderate impact on the modelled ecosystem. Indirect effects are seen to be important, with cod fishing pressure, cod cannibalism and whale predation on cod having an indirect impact on capelin, emphasising the importance of multi-species modelling in understanding and managing ecosystems. Models such as the one presented here provide one step towards an ecosystem-based approach to fisheries management.
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Federal Register 2010, 2011, 2012, 2013, 2014
2011-10-26
... DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration 50 CFR Part 679 [Docket No. 101126521-0640-02] RIN 0648-XA791 Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Catcher/Processors Using Pot Gear in the Bering Sea and Aleutian Islands Management Area AGENCY: National...
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Federal Register 2010, 2011, 2012, 2013, 2014
2011-01-26
... DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration 50 CFR Part 679 [Docket No. 0910131363-0087-02] RIN 0648-XA176 Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Catcher/Processors Using Pot Gear in the Bering Sea and Aleutian Islands Management Area AGENCY: National...
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Federal Register 2010, 2011, 2012, 2013, 2014
2010-02-26
... DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration 50 CFR Part 679 [Docket No. 0810141351-9087-02] RIN 0648-XU65 Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Catcher/Processors Using Pot Gear in the Bering Sea and Aleutian Islands Management Area AGENCY: National Marine...
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Federal Register 2010, 2011, 2012, 2013, 2014
2012-01-25
... DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration 50 CFR Part 679 [Docket No. 101126521-0640-02] RIN 0648-XA955 Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Catcher/Processors Using Pot Gear in the Bering Sea and Aleutian Islands Management Area AGENCY: National...
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Federal Register 2010, 2011, 2012, 2013, 2014
2010-09-27
... DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration 50 CFR Part 679 [Docket No. 0910131363-0087-02] RIN 0648-XZ27 Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Catcher/Processors Using Pot Gear in the Bering Sea and Aleutian Islands Management Area AGENCY: National Marine...
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Federal Register 2010, 2011, 2012, 2013, 2014
2013-02-01
... DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration 50 CFR Part 679 [Docket No. 111213751-2102-02] RIN 0648-XC465 Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Catcher/Processors Using Pot Gear in the Bering Sea and Aleutian Islands Management Area AGENCY: National...
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Yakubu, Abdul-Aziz; Li, Nianpeng; Conrad, Jon M; Zeeman, Mary-Lou
2011-07-01
Overfishing, pollution and other environmental factors have greatly reduced commercially valuable stocks of fish. In a 2006 Science article, a group of ecologists and economists warned that the world may run out of seafood from natural stocks if overfishing continues at current rates. In this paper, we explore the interaction between a constant proportion harvest policy and recruitment dynamics. We examine the discrete-time constant proportion harvest policy discussed in Ang et al. (2009) and then expand the framework to include stock-recruitment functions that are compensatory and overcompensatory, both with and without the Allee effect. We focus on constant proportion policies (CPPs). CPPs have the potential to stabilize complex overcompensatory stock dynamics, with or without the Allee effect, provided the rates of harvest stay below a threshold. If that threshold is exceeded, CPPs are known to result in the sudden collapse of a fish stock when stock recruitment exhibits the Allee effect. In case studies, we analyze CPPs as they might be applied to Gulf of Alaska Pacific halibut fishery and the Georges Bank Atlantic cod fishery based on harvest rates from 1975 to 2007. The best fit models suggest that, under high fishing mortalities, the halibut fishery is vulnerable to sudden population collapse while the cod fishery is vulnerable to steady decline to zero. The models also suggest that CPP with mean harvesting levels from the last 30 years can be effective at preventing collapse in the halibut fishery, but these same policies would lead to steady decline to zero in the Atlantic cod fishery. We observe that the likelihood of collapse in both fisheries increases with increased stochasticity (for example, weather variability) as predicted by models of global climate change. Copyright © 2011 Elsevier Inc. All rights reserved.
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76 FR 2084 - North Pacific Fishery Management Council; Public Meetings
Federal Register 2010, 2011, 2012, 2013, 2014
2011-01-12
... Amendment(T). 6. Aleutian Island (AI) Pacific Cod Issues: Discussion paper on BS&AI Pacific cod Split take action as necessary; Initial review AI Pacific cod processing Sideboards; (postponed). 7. BSAI Crab.... AI Pacific Cod. 4. BSAI Crab Management. 5. Miscellaneous Groundfish. 6. Economic SAFE review. 7...
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Federal Register 2010, 2011, 2012, 2013, 2014
2011-10-27
... Octopus in the Bering Sea and Aleutian Islands Management Area AGENCY: National Marine Fisheries Service... catch of octopus by vessels using pot gear to fish for Pacific cod the BSAI. DATES: Effective 1200 hrs... and management measures prevent overfishing. The 2011 octopus overfishing level in the BSAI is 528...
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Federal Register 2010, 2011, 2012, 2013, 2014
2013-12-06
.... 120918468-3111-02] RIN 0648-XC975 Fisheries of the Exclusive Economic Zone Off Alaska; Reallocation of Pacific Cod in the Western Regulatory Area of the Gulf of Alaska Management Area AGENCY: National Marine... the Western Regulatory Area of the Gulf of Alaska management area (GOA). This action is necessary to...
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Federal Register 2010, 2011, 2012, 2013, 2014
2010-02-19
.... 0810141351-9087-02] RIN 0648-XU36 Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Catcher/Processors Using Hook-and-Line Gear in the Bering Sea and Aleutian Islands Management Area AGENCY: National... using hook-and-line gear in the Bering Sea and Aleutian Islands management area (BSAI). This action is...
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Harvesting Atlantic Cod under Climate Variability
NASA Astrophysics Data System (ADS)
Oremus, K. L.
2016-12-01
Previous literature links the growth of a fishery to climate variability. This study uses an age-structured bioeconomic model to compare optimal harvest in the Gulf of Maine Atlantic cod fishery under a variable climate versus a static climate. The optimal harvest path depends on the relationship between fishery growth and the interest rate, with higher interest rates dictating greater harvests now at the cost of long-term stock sustainability. Given the time horizon of a single generation of fishermen under assumptions of a static climate, the model finds that the economically optimal management strategy is to harvest the entire stock in the short term and allow the fishery to collapse. However, if the biological growth of the fishery is assumed to vary with climate conditions, such as the North Atlantic Oscillation, there will always be pulses of high growth in the stock. During some of these high-growth years, the growth of the stock and its economic yield can exceed the growth rate of the economy even under high interest rates. This implies that it is not economically optimal to exhaust the New England cod fishery if NAO is included in the biological growth function. This finding may have theoretical implications for the management of other renewable yet exhaustible resources whose growth rates are subject to climate variability.
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A bio-economic analysis of harvest control rules for the Northeast Arctic cod fishery.
Eikeset, Anne Maria; Richter, Andries P; Dankel, Dorothy J; Dunlop, Erin S; Heino, Mikko; Dieckmann, Ulf; Stenseth, Nils Chr
2013-05-01
Harvest control rules (HCRs) have been implemented for many fisheries worldwide. However, in most instances, those HCRs are not based on the explicit feedbacks between stock properties and economic considerations. This paper develops a bio-economic model that evaluates the HCR adopted in 2004 by the Joint Norwegian-Russian Fishery Commission to manage the world's largest cod stock, Northeast Arctic cod (NEA). The model considered here is biologically and economically detailed, and is the first to compare the performance of the stock's current HCR with that of alternative HCRs derived with optimality criteria. In particular, HCRs are optimized for economic objectives including fleet profits, economic welfare, and total yield and the emerging properties are analyzed. The performance of these optimal HCRs was compared with the currently used HCR. This paper show that the current HCR does in fact comes very close to maximizing profits. Furthermore, the results reveal that the HCR that maximizes profits is the most precautionary one among the considered HCRs. Finally, the HCR that maximizes yield leads to un-precautionary low levels of biomass. In these ways, the implementation of the HCR for NEA cod can be viewed as a success story that may provide valuable lessons for other fisheries.
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A bio-economic analysis of harvest control rules for the Northeast Arctic cod fishery
Eikeset, Anne Maria; Richter, Andries P.; Dankel, Dorothy J.; Dunlop, Erin S.; Heino, Mikko; Dieckmann, Ulf; Stenseth, Nils Chr.
2013-01-01
Harvest control rules (HCRs) have been implemented for many fisheries worldwide. However, in most instances, those HCRs are not based on the explicit feedbacks between stock properties and economic considerations. This paper develops a bio-economic model that evaluates the HCR adopted in 2004 by the Joint Norwegian–Russian Fishery Commission to manage the world's largest cod stock, Northeast Arctic cod (NEA). The model considered here is biologically and economically detailed, and is the first to compare the performance of the stock's current HCR with that of alternative HCRs derived with optimality criteria. In particular, HCRs are optimized for economic objectives including fleet profits, economic welfare, and total yield and the emerging properties are analyzed. The performance of these optimal HCRs was compared with the currently used HCR. This paper show that the current HCR does in fact comes very close to maximizing profits. Furthermore, the results reveal that the HCR that maximizes profits is the most precautionary one among the considered HCRs. Finally, the HCR that maximizes yield leads to un-precautionary low levels of biomass. In these ways, the implementation of the HCR for NEA cod can be viewed as a success story that may provide valuable lessons for other fisheries. PMID:26525860
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Federal Register 2010, 2011, 2012, 2013, 2014
2013-06-12
.... 080219213-3470-01] RIN 0648-AT31 Atlantic Coastal Fisheries Cooperative Management Act Provisions; American... lobster trap fishery in Lobster Conservation Management Area 2 (Federal nearshore waters in Southern New England; Area 2), and in the Outer Cape Cod Lobster Conservation Management Area (Federal nearshore waters...
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Eide, Arne
2017-12-01
Climate change is expected to influence spatial and temporal distributions of fish stocks. The aim of this paper is to compare climate change impact on a fishery with other factors impacting the performance of fishing fleets. The fishery in question is the Northeast Arctic cod fishery, a well-documented fishery where data on spatial and temporal distributions are available. A cellular automata model is developed for the purpose of mimicking possible distributional patterns and different management alternatives are studied under varying assumptions on the fleets' fishing aptitude. Fisheries management and fishing aptitude, also including technological development and local knowledge, turn out to have the greatest impact on the spatial distribution of the fishing effort, when comparing the IPCC's SRES A1B scenario with repeated sequences of the current environmental situation over a period of 45 years. In both cases, the highest profits in the simulation period of 45 years are obtained at low exploitation levels and moderate fishing aptitude.
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How Many Fish Need to Be Measured to Effectively Evaluate Trawl Selectivity?
Santos, Juan; Sala, Antonello
2016-01-01
The aim of this study was to provide practitioners working with trawl selectivity with general and easily understandable guidelines regarding the fish sampling effort necessary during sea trials. In particular, we focused on how many fish would need to be caught and length measured in a trawl haul in order to assess the selectivity parameters of the trawl at a designated uncertainty level. We also investigated the dependency of this uncertainty level on the experimental method used to collect data and on the potential effects of factors such as the size structure in the catch relative to the size selection of the gear. We based this study on simulated data created from two different fisheries: the Barents Sea cod (Gadus morhua) trawl fishery and the Mediterranean Sea multispecies trawl fishery represented by red mullet (Mullus barbatus). We used these two completely different fisheries to obtain results that can be used as general guidelines for other fisheries. We found that the uncertainty in the selection parameters decreased with increasing number of fish measured and that this relationship could be described by a power model. The sampling effort needed to achieve a specific uncertainty level for the selection parameters was always lower for the covered codend method compared to the paired-gear method. In many cases, the number of fish that would need to be measured to maintain a specific uncertainty level was around 10 times higher for the paired-gear method than for the covered codend method. The trends observed for the effect of sampling effort in the two fishery cases investigated were similar; therefore the guidelines presented herein should be applicable to other fisheries. PMID:27560696
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Archived DNA reveals fisheries and climate induced collapse of a major fishery.
Bonanomi, Sara; Pellissier, Loïc; Therkildsen, Nina Overgaard; Hedeholm, Rasmus Berg; Retzel, Anja; Meldrup, Dorte; Olsen, Steffen Malskær; Nielsen, Anders; Pampoulie, Christophe; Hemmer-Hansen, Jakob; Wisz, Mary Susanne; Grønkjær, Peter; Nielsen, Einar Eg
2015-10-22
Fishing and climate change impact the demography of marine fishes, but it is generally ignored that many species are made up of genetically distinct locally adapted populations that may show idiosyncratic responses to environmental and anthropogenic pressures. Here, we track 80 years of Atlantic cod (Gadus morhua) population dynamics in West Greenland using DNA from archived otoliths in combination with fish population and niche based modeling. We document how the interacting effects of climate change and high fishing pressure lead to dramatic spatiotemporal changes in the proportions and abundance of different genetic populations, and eventually drove the cod fishery to a collapse in the early 1970s. Our results highlight the relevance of fisheries management at the level of genetic populations under future scenarios of climate change.
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Archived DNA reveals fisheries and climate induced collapse of a major fishery
Bonanomi, Sara; Pellissier, Loïc; Therkildsen, Nina Overgaard; Hedeholm, Rasmus Berg; Retzel, Anja; Meldrup, Dorte; Olsen, Steffen Malskær; Nielsen, Anders; Pampoulie, Christophe; Hemmer-Hansen, Jakob; Wisz, Mary Susanne; Grønkjær, Peter; Nielsen, Einar Eg
2015-01-01
Fishing and climate change impact the demography of marine fishes, but it is generally ignored that many species are made up of genetically distinct locally adapted populations that may show idiosyncratic responses to environmental and anthropogenic pressures. Here, we track 80 years of Atlantic cod (Gadus morhua) population dynamics in West Greenland using DNA from archived otoliths in combination with fish population and niche based modeling. We document how the interacting effects of climate change and high fishing pressure lead to dramatic spatiotemporal changes in the proportions and abundance of different genetic populations, and eventually drove the cod fishery to a collapse in the early 1970s. Our results highlight the relevance of fisheries management at the level of genetic populations under future scenarios of climate change. PMID:26489934
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Archived DNA reveals fisheries and climate induced collapse of a major fishery
NASA Astrophysics Data System (ADS)
Bonanomi, Sara; Pellissier, Loïc; Therkildsen, Nina Overgaard; Hedeholm, Rasmus Berg; Retzel, Anja; Meldrup, Dorte; Olsen, Steffen Malskær; Nielsen, Anders; Pampoulie, Christophe; Hemmer-Hansen, Jakob; Wisz, Mary Susanne; Grønkjær, Peter; Nielsen, Einar Eg
2015-10-01
Fishing and climate change impact the demography of marine fishes, but it is generally ignored that many species are made up of genetically distinct locally adapted populations that may show idiosyncratic responses to environmental and anthropogenic pressures. Here, we track 80 years of Atlantic cod (Gadus morhua) population dynamics in West Greenland using DNA from archived otoliths in combination with fish population and niche based modeling. We document how the interacting effects of climate change and high fishing pressure lead to dramatic spatiotemporal changes in the proportions and abundance of different genetic populations, and eventually drove the cod fishery to a collapse in the early 1970s. Our results highlight the relevance of fisheries management at the level of genetic populations under future scenarios of climate change.
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Assessing impacts of simulated oil spills on the Northeast Arctic cod fishery.
Carroll, JoLynn; Vikebø, Frode; Howell, Daniel; Broch, Ole Jacob; Nepstad, Raymond; Augustine, Starrlight; Skeie, Geir Morten; Bast, Radovan; Juselius, Jonas
2018-01-01
We simulate oil spills of 1500 and 4500m 3 /day lasting 14, 45, and 90days in the spawning grounds of the commercial fish species, Northeast Arctic cod. Modeling the life history of individual fish eggs and larvae, we predict deviations from the historical pattern of recruitment to the adult population due to toxic oil exposures. Reductions in survival for pelagic stages of cod were 0-10%, up to a maximum of 43%. These reductions resulted in a decrease in adult cod biomass of <3% for most scenarios, up to a maximum of 12%. In all simulations, the adult population remained at full reproductive potential with a sufficient number of juveniles surviving to replenish the population. The diverse age distribution helps protect the adult cod population from reductions in a single year's recruitment after a major oil spill. These results provide insights to assist in managing oil spill impacts on fisheries. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.
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Federal Register 2010, 2011, 2012, 2013, 2014
2010-04-15
... is opening directed fishing for Pacific cod by catcher vessels less than 60 feet (18.3 meters) length... meters) length overall using hook-and-line or pot gear in the BSAI under Sec. 679.20(d)(1)(iii) on March... 400 metric tons of Pacific cod remain in the 2010 Pacific cod apportionment for catcher vessels less...
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Hutchings, Jeffrey A
2009-08-01
I examined how the fitness (r) associated with early- and late-maturing genotypes varies with fishing mortality (F) and age-/size-specific probability of capture. Life-history data on Newfoundland's northern Atlantic cod (Gadus morhua) allowed for the estimation of r for individuals maturing at 4 and 7 year in the absence of fishing. Catch selectivity data associated with four types of fishing gear (trap, gillnet, handline, otter trawl) were then incorporated to examine how r varied with gear type and with F. The resulting fitness functions were then used to estimate the F above which selection would favour early (4 year) rather than delayed (7 year) maturity. This evolutionarily-sensitive threshold, F evol, identifies a limit reference point somewhat similar to those used to define overfishing (e.g., F msy, F 0.1). Over-exploitation of northern cod resulted in fishing mortalities considerably greater than those required to effect evolutionary change. Selection for early maturity is reduced by the dome-shaped selectivities characteristic of fixed gears such as handlines (the greater the leptokurtosis, the lower the probability of a selection response) and enhanced by the knife-edged selectivities of bottom trawls. Strategies to minimize genetic change are consistent with traditional management objectives (e.g., yield maximization, population increase). Compliance with harvest control rules guided by evolutionarily-sensitive limit reference points, which may be achieved by adherence to traditional reference points such as F msy and F 0.1, should be sufficient to minimize the probability of fisheries-induced evolution for commercially exploited species.
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Walsh, Philip; Favaro, Brett
2017-01-01
Pots (also known as traps) are baited fishing gears widely used in commercial fisheries, and are being considered as a tool for harvesting Atlantic cod (Gadus morhua) in Newfoundland and Labrador, Canada. Pots produce lower environmental impacts than many other fishing gears, but they will only be a viable fishing strategy if they are efficient and selective at catching their target species. To study the behaviour of cod in and around pots, and how those behaviours affect pot efficiency, we used long-duration underwater video cameras to assess two models of cod pot deployed in the nearshore waters of Fogo Island, NL. We examined the number of cod that approached the pot, the number and proportion that successfully completed entries into the pot openings, and the number that exited, and related these factors to the direction of water movement. We observed very few entry attempts relative to the number of approaches by cod, and only 22% of all entry attempts were successful. We observed that 50% of approaches, 70% of entry attempts, and 73% of successful entrances occurred against the current, and 25% of cod were able to exit the pot following capture. Based on our observations, we suggest that future cod pots should have a greater number of entrances, or a mechanism to ensure that entrances rotate in line with the current, in order to maximize their catch efficiency for cod. PMID:28194312
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Meintzer, Phillip; Walsh, Philip; Favaro, Brett
2017-01-01
Pots (also known as traps) are baited fishing gears widely used in commercial fisheries, and are being considered as a tool for harvesting Atlantic cod ( Gadus morhua ) in Newfoundland and Labrador, Canada. Pots produce lower environmental impacts than many other fishing gears, but they will only be a viable fishing strategy if they are efficient and selective at catching their target species. To study the behaviour of cod in and around pots, and how those behaviours affect pot efficiency, we used long-duration underwater video cameras to assess two models of cod pot deployed in the nearshore waters of Fogo Island, NL. We examined the number of cod that approached the pot, the number and proportion that successfully completed entries into the pot openings, and the number that exited, and related these factors to the direction of water movement. We observed very few entry attempts relative to the number of approaches by cod, and only 22% of all entry attempts were successful. We observed that 50% of approaches, 70% of entry attempts, and 73% of successful entrances occurred against the current, and 25% of cod were able to exit the pot following capture. Based on our observations, we suggest that future cod pots should have a greater number of entrances, or a mechanism to ensure that entrances rotate in line with the current, in order to maximize their catch efficiency for cod.
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Eikeset, Anne Maria; Dunlop, Erin S; Heino, Mikko; Storvik, Geir; Stenseth, Nils C; Dieckmann, Ulf
2016-12-27
The relative roles of density dependence and life history evolution in contributing to rapid fisheries-induced trait changes remain debated. In the 1930s, northeast Arctic cod (Gadus morhua), currently the world's largest cod stock, experienced a shift from a traditional spawning-ground fishery to an industrial trawl fishery with elevated exploitation in the stock's feeding grounds. Since then, age and length at maturation have declined dramatically, a trend paralleled in other exploited stocks worldwide. These trends can be explained by demographic truncation of the population's age structure, phenotypic plasticity in maturation arising through density-dependent growth, fisheries-induced evolution favoring faster-growing or earlier-maturing fish, or a combination of these processes. Here, we use a multitrait eco-evolutionary model to assess the capacity of these processes to reproduce 74 y of historical data on age and length at maturation in northeast Arctic cod, while mimicking the stock's historical harvesting regime. Our results show that model predictions critically depend on the assumed density dependence of growth: when this is weak, life history evolution might be necessary to prevent stock collapse, whereas when a stronger density dependence estimated from recent data is used, the role of evolution in explaining fisheries-induced trait changes is diminished. Our integrative analysis of density-dependent growth, multitrait evolution, and stock-specific time series data underscores the importance of jointly considering evolutionary and ecological processes, enabling a more comprehensive perspective on empirically observed stock dynamics than previous studies could provide.
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Booman, Marije; Borza, Tudor; Feng, Charles Y; Hori, Tiago S; Higgins, Brent; Culf, Adrian; Léger, Daniel; Chute, Ian C; Belkaid, Anissa; Rise, Marlies; Gamperl, A Kurt; Hubert, Sophie; Kimball, Jennifer; Ouellette, Rodney J; Johnson, Stewart C; Bowman, Sharen; Rise, Matthew L
2011-08-01
The collapse of Atlantic cod (Gadus morhua) wild populations strongly impacted the Atlantic cod fishery and led to the development of cod aquaculture. In order to improve aquaculture and broodstock quality, we need to gain knowledge of genes and pathways involved in Atlantic cod responses to pathogens and other stressors. The Atlantic Cod Genomics and Broodstock Development Project has generated over 150,000 expressed sequence tags from 42 cDNA libraries representing various tissues, developmental stages, and stimuli. We used this resource to develop an Atlantic cod oligonucleotide microarray containing 20,000 unique probes. Selection of sequences from the full range of cDNA libraries enables application of the microarray for a broad spectrum of Atlantic cod functional genomics studies. We included sequences that were highly abundant in suppression subtractive hybridization (SSH) libraries, which were enriched for transcripts responsive to pathogens or other stressors. These sequences represent genes that potentially play an important role in stress and/or immune responses, making the microarray particularly useful for studies of Atlantic cod gene expression responses to immune stimuli and other stressors. To demonstrate its value, we used the microarray to analyze the Atlantic cod spleen response to stimulation with formalin-killed, atypical Aeromonas salmonicida, resulting in a gene expression profile that indicates a strong innate immune response. These results were further validated by quantitative PCR analysis and comparison to results from previous analysis of an SSH library. This study shows that the Atlantic cod 20K oligonucleotide microarray is a valuable new tool for Atlantic cod functional genomics research.
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Could Seals Prevent Cod Recovery in the Baltic Sea?
MacKenzie, Brian R.; Eero, Margit; Ojaveer, Henn
2011-01-01
Fish populations are increasingly affected by multiple human and natural impacts including exploitation, eutrophication, habitat alteration and climate change. As a result many collapsed populations may have to recover in ecosystems whose structure and functioning differ from those in which they were formerly productive and supported sustainable fisheries. Here we investigate how a cod (Gadus morhua) population in the Baltic Sea whose biomass was reduced due to a combination of high exploitation and deteriorating environmental conditions might recover and develop in the 21st century in an ecosystem that likely will change due to both the already started recovery of a cod predator, the grey seal Halichoerus grypus, and projected climate impacts. Simulation modelling, assuming increased seal predation, fishing levels consistent with management plan targets and stable salinity, shows that the cod population could reach high levels well above the long-term average. Scenarios with similar seal and fishing levels but with 15% lower salinity suggest that the Baltic will still be able to support a cod population which can sustain a fishery, but biomass and yields will be lower. At present knowledge of cod and seal interactions, seal predation was found to have much lower impact on cod recovery, compared to the effects of exploitation and salinity. These results suggest that dual management objectives (recovery of both seal and cod populations) are realistic but success in achieving these goals will also depend on how climate change affects cod recruitment. PMID:21573062
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Federal Register 2010, 2011, 2012, 2013, 2014
2011-12-01
... GOA Pacific cod TACs among gear and operation type, based primarily on historical dependency and catch... 83 sector allocations are based on historical dependency, each sector's retained catch history of the...
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The origins of intensive marine fishing in medieval Europe: the English evidence.
Barrett, James H; Locker, Alison M; Roberts, Callum M
2004-12-07
The catastrophic impact of fishing pressure on species such as cod and herring is well documented. However, the antiquity of their intensive exploitation has not been established. Systematic catch statistics are only available for ca.100 years, but large-scale fishing industries existed in medieval Europe and the expansion of cod fishing from the fourteenth century (first in Iceland, then in Newfoundland) played an important role in the European colonization of the Northwest Atlantic. History has demonstrated the scale of these late medieval and post-medieval fisheries, but only archaeology can illuminate earlier practices. Zooarchaeological evidence shows that the clearest changes in marine fishing in England between AD 600 and 1600 occurred rapidly around AD 1000 and involved large increases in catches of herring and cod. Surprisingly, this revolution predated the documented post-medieval expansion of England's sea fisheries and coincided with the Medieval Warm Period--when natural herring and cod productivity was probably low in the North Sea. This counterintuitive discovery can be explained by the concurrent rise of urbanism and human impacts on freshwater ecosystems. The search for 'pristine' baselines regarding marine ecosystems will thus need to employ medieval palaeoecological proxies in addition to recent fisheries data and early modern historical records.
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The origins of intensive marine fishing in medieval Europe: the English evidence.
Barrett, James H.; Locker, Alison M.; Roberts, Callum M.
2004-01-01
The catastrophic impact of fishing pressure on species such as cod and herring is well documented. However, the antiquity of their intensive exploitation has not been established. Systematic catch statistics are only available for ca.100 years, but large-scale fishing industries existed in medieval Europe and the expansion of cod fishing from the fourteenth century (first in Iceland, then in Newfoundland) played an important role in the European colonization of the Northwest Atlantic. History has demonstrated the scale of these late medieval and post-medieval fisheries, but only archaeology can illuminate earlier practices. Zooarchaeological evidence shows that the clearest changes in marine fishing in England between AD 600 and 1600 occurred rapidly around AD 1000 and involved large increases in catches of herring and cod. Surprisingly, this revolution predated the documented post-medieval expansion of England's sea fisheries and coincided with the Medieval Warm Period--when natural herring and cod productivity was probably low in the North Sea. This counterintuitive discovery can be explained by the concurrent rise of urbanism and human impacts on freshwater ecosystems. The search for 'pristine' baselines regarding marine ecosystems will thus need to employ medieval palaeoecological proxies in addition to recent fisheries data and early modern historical records. PMID:15590590
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Federal Register 2010, 2011, 2012, 2013, 2014
2013-03-25
... Catcher Vessels Greater Than or Equal to 50 Feet (15.2 Meters) Length Overall Using Hook-and-Line Gear in...: NMFS is prohibiting directed fishing for Pacific cod by catcher vessels (CVs) greater than or equal to... of the 2013 Pacific cod total allowable catch apportioned to CVs greater than or equal to 50 feet (15...
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Eikeset, Anne Maria; Dunlop, Erin S.; Heino, Mikko; Storvik, Geir; Stenseth, Nils C.; Dieckmann, Ulf
2016-01-01
The relative roles of density dependence and life history evolution in contributing to rapid fisheries-induced trait changes remain debated. In the 1930s, northeast Arctic cod (Gadus morhua), currently the world’s largest cod stock, experienced a shift from a traditional spawning-ground fishery to an industrial trawl fishery with elevated exploitation in the stock’s feeding grounds. Since then, age and length at maturation have declined dramatically, a trend paralleled in other exploited stocks worldwide. These trends can be explained by demographic truncation of the population’s age structure, phenotypic plasticity in maturation arising through density-dependent growth, fisheries-induced evolution favoring faster-growing or earlier-maturing fish, or a combination of these processes. Here, we use a multitrait eco-evolutionary model to assess the capacity of these processes to reproduce 74 y of historical data on age and length at maturation in northeast Arctic cod, while mimicking the stock’s historical harvesting regime. Our results show that model predictions critically depend on the assumed density dependence of growth: when this is weak, life history evolution might be necessary to prevent stock collapse, whereas when a stronger density dependence estimated from recent data is used, the role of evolution in explaining fisheries-induced trait changes is diminished. Our integrative analysis of density-dependent growth, multitrait evolution, and stock-specific time series data underscores the importance of jointly considering evolutionary and ecological processes, enabling a more comprehensive perspective on empirically observed stock dynamics than previous studies could provide. PMID:27940913
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Federal Register 2010, 2011, 2012, 2013, 2014
2010-04-15
... gear to catcher vessels less than 60 feet (18.3 meters) length overall (LOA) using hook-and-line or pot... vessels will not be able to harvest 400 mt of the B season apportionment of the 2010 Pacific cod TAC...)(iii)(A), NMFS apportions 400 mt of Pacific cod from the B season jig gear apportionment to catcher...
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Federal Register 2010, 2011, 2012, 2013, 2014
2010-08-26
... is opening directed fishing for Pacific cod by catcher vessels less than 60 feet (18.3 meters) length... catcher vessels less than 60 feet (18.3 meters) LOA using hook-and-line or pot gear specified for the BSAI... 679. NMFS closed directed fishing for Pacific cod by catcher vessels less than 60 feet (18.3 meters...
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Käll, Filip; Hansson, Martin; Baranova, Tatjana; Karlsson, Olle; Lundström, Karl; Neuenfeldt, Stefan; Hjelm, Joakim
2016-01-01
Investigating the factors regulating fish condition is crucial in ecology and the management of exploited fish populations. The body condition of cod (Gadus morhua) in the Baltic Sea has dramatically decreased during the past two decades, with large implications for the fishery relying on this resource. Here, we statistically investigated the potential drivers of the Baltic cod condition during the past 40 years using newly compiled fishery-independent biological data and hydrological observations. We evidenced a combination of different factors operating before and after the ecological regime shift that occurred in the Baltic Sea in the early 1990s. The changes in cod condition related to feeding opportunities, driven either by density-dependence or food limitation, along the whole period investigated and to the fivefold increase in the extent of hypoxic areas in the most recent 20 years. Hypoxic areas can act on cod condition through different mechanisms related directly to species physiology, or indirectly to behaviour and trophic interactions. Our analyses found statistical evidence for an effect of the hypoxia-induced habitat compression on cod condition possibly operating via crowding and density-dependent processes. These results furnish novel insights into the population dynamics of Baltic Sea cod that can aid the management of this currently threatened population. PMID:27853557
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Federal Register 2010, 2011, 2012, 2013, 2014
2012-10-31
... Administrator has also determined that this unharvested amount is unlikely to be harvested through the hierarchy.... Immediate notification is necessary to allow for the orderly conduct and efficient operation of this fishery...
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Federal Register 2010, 2011, 2012, 2013, 2014
2011-05-02
... catch of Pacific cod to be harvested. DATES: Effective April 30, 2011, through 2400 hrs, Alaska local... gear is 207 mt for the period 2400 hrs, A.l.t., January 1, 2011, through 1200 hrs, A.l.t., June 10...
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77 FR 19231 - New England Fishery Management Council; Public Meeting
Federal Register 2010, 2011, 2012, 2013, 2014
2012-03-30
... ABC recommendations for redfish, Georges Bank haddock, Gulf of Maine/ Georges Bank windowpane flounder... 2013 and 2014 ABC recommendations for Georges Bank cod, Gulf of Maine haddock, Cape Cod/ Gulf of Maine yellowtail flounder, American plaice, witch flounder and Georges Bank/Gulf of Maine white hake. c. Other...
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Federal Register 2010, 2011, 2012, 2013, 2014
2011-03-10
... Catcher Vessels Less Than 60 Feet (18.3 m) Length Overall Using Hook-and-Line or Pot Gear in the Bering... prohibiting directed fishing for Pacific cod by catcher vessels less than 60 feet (18.3 m) length overall (LOA...
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Federal Register 2010, 2011, 2012, 2013, 2014
2012-09-11
... closure. SUMMARY: NMFS is opening directed fishing for Pacific cod by catcher vessels less than 60 feet... Pacific cod allocated to catcher vessels less than 60 feet LOA using hook-and-line or pot gear in the BSAI... vessels less than 60 feet LOA using hook-and-line or pot gear in the BSAI under Sec. 679.20(d)(1)(iii) on...
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Federal Register 2010, 2011, 2012, 2013, 2014
2011-05-02
... closure. SUMMARY: NMFS is opening directed fishing for Pacific cod by catcher vessels less than 60 feet... Pacific cod allocated to catcher vessels less than 60 feet LOA using hook-and-line or pot gear in the BSAI... less than 60 feet LOA using hook-and-line or pot gear in the BSAI under Sec. 679.20(d)(1)(iii) on March...
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Effects of climate change on the survival of larval cod
NASA Astrophysics Data System (ADS)
Kristiansen, T.; Stock, C. A.; Drinkwater, K. F.; Curchitser, E. N.
2011-12-01
Understanding how climate change may impact important commercial fisheries is critical for developing sustainable fisheries management strategies. In this study, we used simulations from an Earth System Model (NOAA GFDL ESM2.1) coupled with an individual-based model (IBM) for larval fish to provide a first assessment of the potential importance of climate-change driven changes in primary productivity and temperature on cod recruitment in the North Atlantic to the year 2100. ESM model output was averaged for 5 regions, each with an area of 5x5 on a latitude-longitude grid, and representing the geographic boundaries of the current cod range. The physical and environmental data were incorporated into a mechanistic IBM used to simulate the critical early phases in the life of larval fish (e.g. cod) in a changing environment. Large phytoplankton production was predicted to decrease in most regions, thereby lowering the number of meso-zooplankton in the water column. Meso-zooplankton is the most important prey item for larval cod and a reduction in their numbers have strong impacts on larval cod survival. The combination of lowered prey abundance with increased energy requirement for growth and metabolism through increased temperature had a negative impact on cod recruitment in all modeled regions of the North Atlantic. The probability of survival past the larval stages was reduced with 20-30% at all five spawning grounds by the year 2100. Together, these results suggest climate change could have significant impacts on the survival of larval cod in the North Atlantic.
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75 FR 20344 - North Pacific Fishery Management Council; Public Meeting
Federal Register 2010, 2011, 2012, 2013, 2014
2010-04-19
...) groundfish plan teams will meet via teleconference May 6, 2010, 12:30 p.m. Alaska Standard Time (AST) to review proposals for models to be considered for inclusion in the GOA and BSAI Pacific cod assessments... INFORMATION: Agenda: Review proposals for models Pacific cod stock assessments. The agenda is posted on the...
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Federal Register 2010, 2011, 2012, 2013, 2014
2013-08-27
... this unharvested amount is unlikely to be harvested through the hierarchy set forth in Sec. 679.20(a)(7... orderly conduct and efficient operation of this fishery, to allow the industry to plan for the fishing...
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Federal Register 2010, 2011, 2012, 2013, 2014
2013-09-25
... harvested through the hierarchy set forth in Sec. 679.20(a)(7)(iii)(A). Therefore, in accordance with Sec... operation of this fishery, to allow the industry to plan for the fishing season, and to avoid potential...
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Commons versus Open Access: The Collapse of Canada's East Coast Fishery.
ERIC Educational Resources Information Center
Matthews, David Ralph
1995-01-01
The consequences of management espousal of the "Tragedy of the Commons" theory has been starkly illustrated by the crash in cod stocks off Canada's east coast. The voices of fishers from several different coastal communities testify to the inadequacy of Canadian government fisheries policy. (LZ)
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Federal Register 2010, 2011, 2012, 2013, 2014
2012-03-14
..., sablefish, deep-water flatfish, rex sole, Pacific ocean perch, northern rockfish, shortraker rockfish... cod, shallow-water flatfish, arrowtooth flounder, flathead sole, ``other rockfish'' in the Eastern GOA...) guideline harvest levels (GHLs) for Pacific cod so that the ABC is not exceeded. The shallow-water flatfish...
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Federal Register 2010, 2011, 2012, 2013, 2014
2011-04-20
... Catcher Vessels Using Trawl Gear in the Bering Sea and Aleutian Islands Management Area AGENCY: National... catcher vessels using trawl gear in the Bering Sea and Aleutian Islands Management Area (BSAI). This... Pacific cod allocated to catcher vessels using trawl gear in the BSAI. DATES: Effective 1200 hrs, Alaska...
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Federal Register 2010, 2011, 2012, 2013, 2014
2011-04-14
... Catcher Vessels Using Trawl Gear in the Bering Sea and Aleutian Islands Management Area AGENCY: National... catcher vessels using trawl gear in the Bering Sea and Aleutian Islands Management Area (BSAI). This... Pacific cod allocated to catcher vessels using trawl gear in the BSAI. DATES: Effective 1200 hrs, Alaska...
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Árnason, Einar
2015-01-01
Natural selection, the most important force in evolution, comes in three forms. Negative purifying selection removes deleterious variation and maintains adaptations. Positive directional selection fixes beneficial variants, producing new adaptations. Balancing selection maintains variation in a population. Important mechanisms of balancing selection include heterozygote advantage, frequency-dependent advantage of rarity, and local and fluctuating episodic selection. A rare pathogen gains an advantage because host defenses are predominantly effective against prevalent types. Similarly, a rare immune variant gives its host an advantage because the prevalent pathogens cannot escape the host’s apostatic defense. Due to the stochastic nature of evolution, neutral variation may accumulate on genealogical branches, but trans-species polymorphisms are rare under neutrality and are strong evidence for balancing selection. Balanced polymorphism maintains diversity at the major histocompatibility complex (MHC) in vertebrates. The Atlantic cod is missing genes for both MHC-II and CD4, vital parts of the adaptive immune system. Nevertheless, cod are healthy in their ecological niche, maintaining large populations that support major commercial fisheries. Innate immunity is of interest from an evolutionary perspective, particularly in taxa lacking adaptive immunity. Here, we analyze extensive amino acid and nucleotide polymorphisms of the cathelicidin gene family in Atlantic cod and closely related taxa. There are three major clusters, Cath1, Cath2, and Cath3, that we consider to be paralogous genes. There is extensive nucleotide and amino acid allelic variation between and within clusters. The major feature of the results is that the variation clusters by alleles and not by species in phylogenetic trees and discriminant analysis of principal components. Variation within the three groups shows trans-species polymorphism that is older than speciation and that is suggestive of balancing selection maintaining the variation. Using Bayesian and likelihood methods positive and negative selection is evident at sites in the conserved part of the genes and, to a larger extent, in the active part which also shows episodic diversifying selection, further supporting the argument for balancing selection. PMID:26038731
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Federal Register 2010, 2011, 2012, 2013, 2014
2012-06-15
... Fisheries Service (NMFS), National Oceanic and Atmospheric Administration (NOAA), Commerce. ACTION: Proposed... carry one observer and use a motion-compensated scale to weigh Pacific cod before it is processed. The... and catch reporting requirements that apply to catcher/processors not subject to this proposed action...
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Federal Register 2010, 2011, 2012, 2013, 2014
2011-04-18
... DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration RIN 0648-XA361 Fisheries of the Exclusive Economic Zone Off Alaska; Catch Accounting in the Longline Catcher/Processor Pacific Cod... longliners in the Bering Sea and Aleutian Islands to support different catch accounting methods for Pacific...
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Federal Register 2010, 2011, 2012, 2013, 2014
2013-02-26
... halibut PSC trawl limits between the trawl gear deep-water and the shallow-water species fishery... for pollock, sablefish, deep-water flatfish, rex sole, Pacific ocean perch, northern rockfish... less than the ABCs for Pacific cod, shallow-water flatfish, arrowtooth flounder, flathead sole, ``other...
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Federal Register 2010, 2011, 2012, 2013, 2014
2012-04-18
... Catcher Vessels Using Trawl Gear in the Bering Sea and Aleutian Islands Management Area AGENCY: National... using trawl gear in the Bering Sea and Aleutian Islands management area (BSAI). This action is necessary... fishing for Pacific cod by catcher vessels using trawl gear in the BSAI. After the effective date of this...
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Federal Register 2010, 2011, 2012, 2013, 2014
2011-03-28
... mt (1,102,311 lbs) of GOA Pacific cod from 1996 through 2000, and the vessel's catch history... submit confidential business information or otherwise sensitive or protected information. NMFS will... allocation of crab QS was based on a qualifying harvest history in a CR Program fishery. Each QS allocation...
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Federal Register 2010, 2011, 2012, 2013, 2014
2010-07-13
... Fisheries Act (AFA) trawl catcher/processor sector (otherwise known as the Amendment 80 sector... catcher/processors. Hook-and-line catcher/processors are allocated 48.7 percent of the annual BSAI Pacific... harvest of Pacific cod by hook-and-line catcher/processors, although this is one of the major groundfish...
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Federal Register 2010, 2011, 2012, 2013, 2014
2010-09-10
... require that any overage of the GB yellowtail flounder TAC specified for the common pool, individual... deduction will be divided between the annual catch limit (ACL) for common pool vessels (common pool sub-ACL... that ``any overages of the GB cod and GB haddock TACs specified for either the common pool or...
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Federal Register 2010, 2011, 2012, 2013, 2014
2010-08-11
... under common pool regulations for the 2010 fishing year (FY). This action also corrects a previously published cod trip limit for common pool vessels fishing under a limited access Handgear A permit. This... common pool (common pool sub-ACL) and underharvesting the sub-ACL for pollock during FY 2010 (May 1, 2010...
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The Impact of Subsidies on the Ecological Sustainability and Future Profits from North Sea Fisheries
Heymans, Johanna Jacomina; Mackinson, Steven; Sumaila, Ussif Rashid; Dyck, Andrew; Little, Alyson
2011-01-01
Background This study examines the impact of subsidies on the profitability and ecological stability of the North Sea fisheries over the past 20 years. It shows the negative impact that subsidies can have on both the biomass of important fish species and the possible profit from fisheries. The study includes subsidies in an ecosystem model of the North Sea and examines the possible effects of eliminating fishery subsidies. Methodology/Principal Findings Hindcast analysis between 1991 and 2003 indicates that subsidies reduced the profitability of the fishery even though gross revenue might have been high for specific fisheries sectors. Simulations seeking to maximise the total revenue between 2004 and 2010 suggest that this can be achieved by increasing the effort of Nephrops trawlers, beam trawlers, and the pelagic trawl-and-seine fleet, while reducing the effort of demersal trawlers. Simulations show that ecological stability can be realised by reducing the effort of the beam trawlers, Nephrops trawlers, pelagic- and demersal trawl-and-seine fleets. This analysis also shows that when subsidies are included, effort will always be higher for all fleets, because it effectively reduces the cost of fishing. Conclusions/Significance The study found that while removing subsidies might reduce the total catch and revenue, it increases the overall profitability of the fishery and the total biomass of commercially important species. For example, cod, haddock, herring and plaice biomass increased over the simulation when optimising for profit, and when optimising for ecological stability, the biomass for cod, plaice and sole also increased. When subsidies are eliminated, the study shows that rather than forcing those involved in the fishery into the red, fisheries become more profitable, despite a decrease in total revenue due to a loss of subsidies from the government. PMID:21637848
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Federal Register 2010, 2011, 2012, 2013, 2014
2010-08-26
... trawl catcher vessels to catcher vessels less than 60 feet (18.3 meters) length overall (LOA) using hook... cod from the C season trawl catcher vessel apportionment to catcher vessels less than 60 feet (18.3... vessels less than 60 feet (18.3 m) LOA using hook-and-line or pot gear. Classification This action...
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Federal Register 2010, 2011, 2012, 2013, 2014
2010-03-12
... TACs for 2010 and 2011 that are equal to ABCs for pollock, deep-water flatfish, rex sole, sablefish... recommended TACs for 2010 and 2011 that are less than the ABCs for Pacific cod, flathead sole, shallow-water... that the sum of all State and Federal water Pacific cod removals from the GOA not exceed ABC...
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Federal Register 2010, 2011, 2012, 2013, 2014
2012-10-15
... Vessels Using Pot Gear in the Central Regulatory Area of the Gulf of Alaska AGENCY: National Marine... gear in the Central Regulatory Area of the Gulf of Alaska (GOA). This action is necessary to prevent exceeding the 2012 Pacific cod total allowable catch apportioned to vessels using pot gear in the Central...
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Federal Register 2010, 2011, 2012, 2013, 2014
2013-03-01
.... 1801 et seq. Dated: February 26, 2013. Kara Meckley, Acting Deputy Director, Office of Sustainable... hours. This action is necessary to fully use the A season allowance of the 2013 Pacific cod total...: Effective 1200 hours, Alaska local time (A.l.t.), March 1, 2013, through 1200 hours, A.l.t., March 3, 2013...
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Kleiven, Alf Ring; Fernandez-Chacon, Albert; Nordahl, Jan-Harald; Moland, Even; Espeland, Sigurd Heiberg; Knutsen, Halvor; Olsen, Esben Moland
2016-01-01
Marine recreational fishing is a popular outdoor activity. However, knowledge about the magnitude of recreational catches relative to commercial catches in coastal fisheries is generally sparse. Coastal Atlantic cod (Gadus morhua) is a target species for recreational fishers in the North Atlantic. In Norway, recreational fishers are allowed to use a variety of traps and nets as well as long-line and rod and line when fishing for cod. From 2005 to 2013, 9729 cod (mean size: 40 cm, range: 15–93 cm) were tagged and released in coastal Skagerrak, southeast Norway. Both high-reward (NOK 500) and low-reward tags (NOK 50) were used in this study. Because some harvested fish (even those posting high-reward tags) may go unreported by fishers, reporting rates were estimated from mark-recovery models that incorporate detection parameters in their structure, in addition to survival and mortality estimates. During 2005 to 2013, a total of 1707 tagged cod were recovered and reported by fishers. We estimate the overall annual survival to be 33% (SE 1.5). Recreational rod and line fishing were responsible for 33.7% (SE 2.4) of total mortality, followed by commercial fisheries (15.1% SE 0.8) and recreational fixed gear (6.8% SE 0.4). Natural mortality was 44.4% (SE 2.5) of total mortality. Our findings suggest that recreational fishing—rod and line fishing in particular—is responsible for a substantial part of fishing mortality exerted on coastal cod in southern Norway. PMID:26959371
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Kleiven, Alf Ring; Fernandez-Chacon, Albert; Nordahl, Jan-Harald; Moland, Even; Espeland, Sigurd Heiberg; Knutsen, Halvor; Olsen, Esben Moland
2016-01-01
Marine recreational fishing is a popular outdoor activity. However, knowledge about the magnitude of recreational catches relative to commercial catches in coastal fisheries is generally sparse. Coastal Atlantic cod (Gadus morhua) is a target species for recreational fishers in the North Atlantic. In Norway, recreational fishers are allowed to use a variety of traps and nets as well as long-line and rod and line when fishing for cod. From 2005 to 2013, 9729 cod (mean size: 40 cm, range: 15-93 cm) were tagged and released in coastal Skagerrak, southeast Norway. Both high-reward (NOK 500) and low-reward tags (NOK 50) were used in this study. Because some harvested fish (even those posting high-reward tags) may go unreported by fishers, reporting rates were estimated from mark-recovery models that incorporate detection parameters in their structure, in addition to survival and mortality estimates. During 2005 to 2013, a total of 1707 tagged cod were recovered and reported by fishers. We estimate the overall annual survival to be 33% (SE 1.5). Recreational rod and line fishing were responsible for 33.7% (SE 2.4) of total mortality, followed by commercial fisheries (15.1% SE 0.8) and recreational fixed gear (6.8% SE 0.4). Natural mortality was 44.4% (SE 2.5) of total mortality. Our findings suggest that recreational fishing-rod and line fishing in particular-is responsible for a substantial part of fishing mortality exerted on coastal cod in southern Norway.
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Liu, J; Li, Y P; Huang, G H; Zeng, X T; Nie, S
2016-01-01
In this study, an interval-stochastic-based risk analysis (RSRA) method is developed for supporting river water quality management in a rural system under uncertainty (i.e., uncertainties exist in a number of system components as well as their interrelationships). The RSRA method is effective in risk management and policy analysis, particularly when the inputs (such as allowable pollutant discharge and pollutant discharge rate) are expressed as probability distributions and interval values. Moreover, decision-makers' attitudes towards system risk can be reflected using a restricted resource measure by controlling the variability of the recourse cost. The RSRA method is then applied to a real case of water quality management in the Heshui River Basin (a rural area of China), where chemical oxygen demand (COD), total nitrogen (TN), total phosphorus (TP), and soil loss are selected as major indicators to identify the water pollution control strategies. Results reveal that uncertainties and risk attitudes have significant effects on both pollutant discharge and system benefit. A high risk measure level can lead to a reduced system benefit; however, this reduction also corresponds to raised system reliability. Results also disclose that (a) agriculture is the dominant contributor to soil loss, TN, and TP loads, and abatement actions should be mainly carried out for paddy and dry farms; (b) livestock husbandry is the main COD discharger, and abatement measures should be mainly conducted for poultry farm; (c) fishery accounts for a high percentage of TN, TP, and COD discharges but a has low percentage of overall net benefit, and it may be beneficial to cease fishery activities in the basin. The findings can facilitate the local authority in identifying desired pollution control strategies with the tradeoff between socioeconomic development and environmental sustainability.
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Federal Register 2010, 2011, 2012, 2013, 2014
2011-07-26
... resources within State waters, and the Commissioner of the Alaska Department of Fish and Game (ADF&G) opens... and Game (ADF&G) toward a GHL, which limits catch in the fishery in a manner similar to management of... and operation types, based primarily on historical dependency and use by each sector, while also...
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Federal Register 2010, 2011, 2012, 2013, 2014
2010-03-16
... throughout the Western U.S./Canada Area. In addition, as of March 5, 2010, the catch of Eastern GB cod was 72...; removal of gear restrictions. SUMMARY: This action removes temporary gear restrictions in both the Eastern and Western U.S./Canada Areas for limited access Northeast (NE) multispecies vessels fishing on a NE...
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Federal Register 2010, 2011, 2012, 2013, 2014
2012-06-25
... Management Plan and Sector Annual Catch Entitlements; Updated Annual Catch Limits for Sectors and the Common... either sectors or the common pool fishery. DATES: Effective June 22, 2012, through April 30, 2013. FOR... for GOM cod on May 1, 2012 (77 FR 25623), consistent with the Council's request. The common pool and...
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Federal Register 2010, 2011, 2012, 2013, 2014
2013-01-24
... Catcher Vessels Greater Than or Equal To 60 Feet (18.3 Meters) Length Overall Using Pot Gear in the Bering... prohibiting directed fishing for Pacific cod by pot catcher vessels greater than or equal to 60 feet (18.3... allowable catch (TAC) specified for pot catcher vessels greater than or equal to 60 feet (18.3 m) LOA in the...
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Federal Register 2010, 2011, 2012, 2013, 2014
2013-08-28
... gear and catcher vessels greater than 60 feet (18.3 meters) length overall (LOA) using hook-and-line gear to catcher vessels less than 60 feet (18.3 meters) LOA using hook-and-line or pot gear in the...)(iii)(A), NMFS apportions 2,500 mt of Pacific cod to catcher vessels less than 60 feet (18.3 meters(m...
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Federal Register 2010, 2011, 2012, 2013, 2014
2013-03-25
... Catcher Vessels Less Than 50 Feet (15.2 Meters) Length Overall Using Hook-and-Line Gear in the Central... directed fishing for Pacific cod by catcher vessels (CVs) less than 50 feet (15.2 meters (m)) in length... catch apportioned to CVs less than 50 feet (15.2 m) LOA using hook-and-line gear in the Central...
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Federal Register 2010, 2011, 2012, 2013, 2014
2010-11-26
... Catcher Vessels Less Than 60 Feet (18.3 m) Length Overall Using Hook-and-Line or Pot Gear in the Bering.... SUMMARY: NMFS is prohibiting directed fishing for Pacific cod by catcher vessels less than 60 feet (18.3 m... allocated to catcher vessels less than 60 feet LOA using hook-and-line or pot gear in the BSAI. DATES...
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Federal Register 2010, 2011, 2012, 2013, 2014
2013-03-28
... Catcher Vessels Less Than 60 feet (18.3 meters) Length Overall Using Jig or Hook-and-Line Gear in the... less than 60 feet (18.3 meters (m)) length overall (LOA) using jig or hook-and-line gear in the... action is necessary to prevent exceeding the limit of Pacific cod for catcher vessels less than 60 feet...
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Federal Register 2010, 2011, 2012, 2013, 2014
2012-08-31
... gear, catcher vessels greater than 60 feet (18.3 meters) length overall (LOA) using hook-and-line gear, and catcher vessels using trawl gear to catcher vessels less than 60 feet (18.3 meters) LOA using hook... than 60 feet (18.3 meters(m)) LOA using hook-and- line or pot gear. The 2012 Pacific cod TAC specified...
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Federal Register 2010, 2011, 2012, 2013, 2014
2012-02-22
... Catcher Vessels Less Than 60 Feet (18.3 Meters) Length Overall Using Hook-and-Line or Pot Gear in the...: NMFS is prohibiting directed fishing for Pacific cod by catcher vessels less than 60 feet (18.3 meters... catch (TAC) specified for catcher vessels less than 60 feet (18.3 m) LOA using hook-and-line or pot gear...
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Federal Register 2010, 2011, 2012, 2013, 2014
2013-02-08
... Catcher Vessels Less Than 60 Feet (18.3 Meters) Length Overall Using Hook-and-Line or Pot Gear in the...: NMFS is prohibiting directed fishing for Pacific cod by catcher vessels less than 60 feet (18.3 meters... catch (TAC) specified for catcher vessels less than 60 feet (18.3 m) LOA using hook-and-line or pot gear...
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Federal Register 2010, 2011, 2012, 2013, 2014
2012-01-23
... Catcher Vessels Greater Than or Equal To 60 Feet (18.3 Meters) Length Overall Using Pot Gear in the Bering... prohibiting directed fishing for Pacific cod by pot catcher vessels greater than or equal to 60 feet (18.3... allowable catch (TAC) specified for pot catcher vessels greater than or equal to 60 feet (18.3 m) LOA in the...
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Federal Register 2010, 2011, 2012, 2013, 2014
2010-02-02
... Vessels Greater Than or Equal to 60 Feet (18.3 Meters) Length Overall Using Pot Gear in the Bering Sea and... directed fishing for Pacific cod by pot catcher vessels greater than or equal to 60 feet (18.3 meters (m...) specified for pot catcher vessels greater than or equal to 60 feet (18.3 m) LOA in the BSAI. DATES...
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Federal Register 2010, 2011, 2012, 2013, 2014
2010-05-21
... Vessels Less Than 60 feet (18.3 m) Length Overall Using Hook-and-Line or Pot Gear in the Bering Sea and... directed fishing for Pacific cod by catcher vessels less than 60 feet (18.3 m) length overall (LOA) using... exempt from review under Executive Order 12866. Authority: 16 U.S.C. 1801 et seq. Dated: May 18, 2010...
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Federal Register 2010, 2011, 2012, 2013, 2014
2011-01-24
... Catcher Vessels Greater Than or Equal to 60 Feet (18.3 Meters) Length Overall Using Pot Gear in the Bering... prohibiting directed fishing for Pacific cod by pot catcher vessels greater than or equal to 60 feet (18.3... catch (TAC) specified for pot catcher vessels greater than or equal to 60 feet (18.3 m) LOA in the BSAI...
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NASA Astrophysics Data System (ADS)
Bolle, Loes J.; Rijnsdorp, Adriaan D.; van Neer, Wim; Millner, Richard S.; van Leeuwen, Piet I.; Ervynck, Anton; Ayers, Richard; Ongenae, Ellen
2004-05-01
Fishing effort has strongly increased in the North Sea since the mid-19th century, causing a substantial reduction in the population size of exploited fish stocks. As fisheries research has developed simultaneously with the industrialisation of the fisheries, our knowledge of population dynamics at low levels of exploitations is limited. Otoliths retrieved from archaeological excavations offer a unique opportunity to study growth rates in the past. This study compares historical and present-day growth rates for four commercially important demersal fish species. A total of 2532 modern otoliths (AD 1984-1999) and 1286 historical otoliths (AD 1200-1925) obtained from archaeological excavations in Belgium and Scotland were analysed. Comparison of the growth patterns between eras revealed a major increase in growth rate of haddock, whereas growth changes were not observed in saithe and only in the smaller size classes of plaice and cod. Comparison of our results with literature data indicates that the observed growth rate changes in plaice and cod occurred within the 20th century. Apparently the onset of industrialised fisheries has not greatly affected the growth of plaice, cod and saithe populations in the North Sea. This result contradicts the expectation of density-dependent limitation of growth during the era of pre-industrialised fishing, but is in agreement with the concentration hypothesis of Beverton (Neth. J. Sea Res. 34 (1995) 1) stating that species which concentrate spatially into nursery grounds during their early life-history may 'saturate' the carrying capacity of the juvenile habitat even though the adult part of the population is not limited by the adult habitat.
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Assessing Social – Ecological Trade-Offs to Advance Ecosystem-Based Fisheries Management
Voss, Rudi; Quaas, Martin F.; Schmidt, Jörn O.; Tahvonen, Olli; Lindegren, Martin; Möllmann, Christian
2014-01-01
Modern resource management faces trade-offs in the provision of various ecosystem goods and services to humanity. For fisheries management to develop into an ecosystem-based approach, the goal is not only to maximize economic profits, but to consider equally important conservation and social equity goals. We introduce such a triple-bottom line approach to the management of multi-species fisheries using the Baltic Sea as a case study. We apply a coupled ecological-economic optimization model to address the actual fisheries management challenge of trading-off the recovery of collapsed cod stocks versus the health of ecologically important forage fish populations. Management strategies based on profit maximization would rebuild the cod stock to high levels but may cause the risk of stock collapse for forage species with low market value, such as Baltic sprat (Fig. 1A). Economically efficient conservation efforts to protect sprat would be borne almost exclusively by the forage fishery as sprat fishing effort and profits would strongly be reduced. Unless compensation is paid, this would challenge equity between fishing sectors (Fig. 1B). Optimizing equity while respecting sprat biomass precautionary levels would reduce potential profits of the overall Baltic fishery, but may offer an acceptable balance between overall profits, species conservation and social equity (Fig. 1C). Our case study shows a practical example of how an ecosystem-based fisheries management will be able to offer society options to solve common conflicts between different resource uses. Adding equity considerations to the traditional trade-off between economy and ecology will greatly enhance credibility and hence compliance to management decisions, a further footstep towards healthy fish stocks and sustainable fisheries in the world ocean. PMID:25268117
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Anders, N; Fernö, A; Humborstad, O-B; Løkkeborg, S; Rieucau, G; Utne-Palm, A C
2017-12-01
The present study tested whether the presence of already retained fishes inside baited fish pots acted as a social attraction and affected the entrance probability of Atlantic cod Gadus morhua in a fjord in northern Norway. Video analysis revealed that the probability of an entrance initially increased with the presence of low numbers of fishes inside the pot, but subsequently decreased at a critical number of caught fishes. The critical number was dependent on the size of the G. morhua attempting to enter. This demonstrates that social attraction and repulsion play a role in G. morhua pot fishing and has important implications for the capture efficiency of fisheries executed with pots. © 2017 The Fisheries Society of the British Isles.
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Hui, Tabitha C. Y.; Gryba, Rowenna; Gregr, Edward J.; Trites, Andrew W.
2015-01-01
A leading hypothesis to explain the dramatic decline of Steller sea lions (Eumetopias jubatus) in western Alaska during the latter part of the 20th century is a change in prey availability due to commercial fisheries. We tested this hypothesis by exploring the relationships between sea lion population trends, fishery catches, and the prey biomass accessible to sea lions around 33 rookeries between 2000 and 2008. We focused on three commercially important species that have dominated the sea lion diet during the population decline: walleye pollock, Pacific cod and Atka mackerel. We estimated available prey biomass by removing fishery catches from predicted prey biomass distributions in the Aleutian Islands, Bering Sea and Gulf of Alaska; and modelled the likelihood of sea lions foraging at different distances from rookeries (accessibility) using satellite telemetry locations of tracked animals. We combined this accessibility model with the prey distributions to estimate the prey biomass accessible to sea lions by rookery. For each rookery, we compared sea lion population change to accessible prey biomass. Of 304 comparisons, we found 3 statistically significant relationships, all suggesting that sea lion populations increased with increasing prey accessibility. Given that the majority of comparisons showed no significant effect, it seems unlikely that the availability of pollock, cod or Atka mackerel was limiting sea lion populations in the 2000s. PMID:25950178
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Hui, Tabitha C Y; Gryba, Rowenna; Gregr, Edward J; Trites, Andrew W
2015-01-01
A leading hypothesis to explain the dramatic decline of Steller sea lions (Eumetopias jubatus) in western Alaska during the latter part of the 20th century is a change in prey availability due to commercial fisheries. We tested this hypothesis by exploring the relationships between sea lion population trends, fishery catches, and the prey biomass accessible to sea lions around 33 rookeries between 2000 and 2008. We focused on three commercially important species that have dominated the sea lion diet during the population decline: walleye pollock, Pacific cod and Atka mackerel. We estimated available prey biomass by removing fishery catches from predicted prey biomass distributions in the Aleutian Islands, Bering Sea and Gulf of Alaska; and modelled the likelihood of sea lions foraging at different distances from rookeries (accessibility) using satellite telemetry locations of tracked animals. We combined this accessibility model with the prey distributions to estimate the prey biomass accessible to sea lions by rookery. For each rookery, we compared sea lion population change to accessible prey biomass. Of 304 comparisons, we found 3 statistically significant relationships, all suggesting that sea lion populations increased with increasing prey accessibility. Given that the majority of comparisons showed no significant effect, it seems unlikely that the availability of pollock, cod or Atka mackerel was limiting sea lion populations in the 2000s.
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Federal Register 2010, 2011, 2012, 2013, 2014
2012-09-14
... 709 West 9th Street, Room 420A, Juneau, AK. Comments must be submitted by one of the above methods to... the GOA. In 1997, NMFS increased the MRAs for pollock and Pacific cod from zero to 5 percent when... arrowtooth flounder fishery from zero to 20 percent for deep-water flatfish, rex sole, flathead sole, shallow...
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Federal Register 2010, 2011, 2012, 2013, 2014
2010-03-30
... Vessels Less Than 60 feet (18.3 m) Length Overall Using Hook-and-Line or Pot Gear in the Bering Sea and... directed fishing for Pacific cod by catcher vessels less than 60 feet (18.3 m) length overall (LOA) using... than 60 feet LOA using hook-and-line or pot gear in the BSAI. DATES: Effective 1200 hrs, Alaska local...
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Federal Register 2010, 2011, 2012, 2013, 2014
2011-08-31
... using trawl gear and catcher vessels greater than or equal to 60 feet (18.3 meters (m)) length overall (LOA) using hook-and-line gear to catcher vessels less than 60 feet (18.3 m) LOA using hook-and-line or... catcher vessels less than 60 feet (18.3 m) LOA using hook-and-line or pot gear. The 2011 Pacific cod total...
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Liboiron, Max; Liboiron, France; Wells, Emily; Richárd, Natalie; Zahara, Alexander; Mather, Charles; Bradshaw, Hillary; Murichi, Judyannet
2016-12-15
Marine microplastics are a contaminant of concern because their small size allows ingestion by a wide range of marine life. Using citizen science during the Newfoundland recreational cod fishery, we sampled 205 Atlantic cod (Gadus morhua) destined for human consumption and found that 5 had eaten plastic, an ingestion prevalence rate of 2.4%. This ingestion rate for Atlantic cod is the second lowest recorded rate in the reviewed published literature (the lowest is 1.4%), and the lowest for any fish in the North Atlantic. This is the first report for plastic ingestion in fish in Newfoundland, Canada, a province dependent on fish for sustenance and livelihoods. Copyright © 2016 Elsevier Ltd. All rights reserved.
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Federal Register 2010, 2011, 2012, 2013, 2014
2010-09-27
... the landing limits for Gulf of Maine (GOM) cod to 100 lb (45.4 kg) per days-at-sea (DAS) up to 1000 lb... to 100 lb (45.4 kg) per DAS up to 500 lb (226.8 kg) per trip; expands the trawl gear restriction in... issued a valid limited access NE multispecies permit and fishing under a NE multispecies day- at-sea (DAS...
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75 FR 20566 - North Pacific Fishery Management Council; Public Meeting
Federal Register 2010, 2011, 2012, 2013, 2014
2010-04-20
... review proposals for models to be considered for inclusion in the GOA and BSAI Pacific cod assessments... physically accessible to people with disabilities. Requests for sign language interpretation or other...
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Federal Register 2010, 2011, 2012, 2013, 2014
2013-11-20
...) LOA using hook- and-line or pot gear, American Fisheries Act (AFA) catcher/processors (C/P), Amendment 80 (A80) C/Ps, C/P vessels using pot gear, and C/P vessels using hook-and-line gear in the Bering Sea... meters) LOA using hook-and-line or pot gear, AFA C/P vessels, A80 C/P vessels, C/P vessels using pot gear...
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Konstantinidis, P; Hilton, E J; Matarese, A C
2016-08-01
Three newly discovered larval specimens of the genus Muraenolepis collected from the waters of the western Antarctic Peninsula are described. Knowledge of their natural history is sparse and information about their early life history is based on only a few larval stages. Here, the available literature on larval eel cods is reviewed, and the specimens placed in context. © 2016 The Fisheries Society of the British Isles.
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NASA Astrophysics Data System (ADS)
Pershing, A. J.; Alexander, M. A.; Hernandez, C.; Kerr, L. A.; Le Bris, A.; Mills, K.; Nye, J. A.; Record, N.; Scannell, H. A.; Scott, J. D.; Sherwood, G. D.; Thomas, A. C.
2016-02-01
Climate change is altering conditions in all marine ecosystems, but the pace of change is not uniform. Rapid changes in environmental conditions pose a challenge for resource management, especially when available tools or policies assume the environment is stationary. Between 2004 and 2013, the Gulf of Maine and northwest Atlantic Shelf warmed at a rate that few large marine ecosystems have ever experienced. This warming was associated with a northward shift in the Gulf Stream and with Atlantic Multidecadal Oscillation and Pacific Decadal Oscillation. The unprecedented warming led to reduced recruitment and enhanced mortality of Atlantic cod. Fisheries management has built-in feedbacks designed to reduce quotas as populations decline, but the management process could not keep pace with the rapid temperature-related changes in the Gulf of Maine cod stock. Future recovery of this fishery now depends on both sound management and favorable temperatures. The experience in the Gulf of Maine highlights the need to incorporate environmental factors into resource management and to build resiliency in coupled social-ecological systems. It also highlights a need for scientific and policy guidance for managing species threatened by future warming.
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Hutchinson, William F; Culling, Mark; Orton, David C; Hänfling, Bernd; Lawson Handley, Lori; Hamilton-Dyer, Sheila; O'Connell, Tamsin C; Richards, Michael P; Barrett, James H
2015-09-01
A comparison of ancient DNA (single-nucleotide polymorphisms) and carbon and nitrogen stable isotope evidence suggests that stored cod provisions recovered from the wreck of the Tudor warship Mary Rose, which sank in the Solent, southern England, in 1545, had been caught in northern and transatlantic waters such as the northern North Sea and the fishing grounds of Iceland and Newfoundland. This discovery, underpinned by control data from archaeological samples of cod bones from potential source regions, illuminates the role of naval provisioning in the early development of extensive sea fisheries, with their long-term economic and ecological impacts.
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Hutchinson, William F.; Culling, Mark; Orton, David C.; Hänfling, Bernd; Lawson Handley, Lori; Hamilton-Dyer, Sheila; O'Connell, Tamsin C.; Richards, Michael P.; Barrett, James H.
2015-01-01
A comparison of ancient DNA (single-nucleotide polymorphisms) and carbon and nitrogen stable isotope evidence suggests that stored cod provisions recovered from the wreck of the Tudor warship Mary Rose, which sank in the Solent, southern England, in 1545, had been caught in northern and transatlantic waters such as the northern North Sea and the fishing grounds of Iceland and Newfoundland. This discovery, underpinned by control data from archaeological samples of cod bones from potential source regions, illuminates the role of naval provisioning in the early development of extensive sea fisheries, with their long-term economic and ecological impacts. PMID:26473047
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Therkildsen, Nina Overgaard; Hemmer-Hansen, Jakob; Hedeholm, Rasmus Berg; Wisz, Mary S; Pampoulie, Christophe; Meldrup, Dorte; Bonanomi, Sara; Retzel, Anja; Olsen, Steffen Malskær; Nielsen, Einar Eg
2013-01-01
Accurate prediction of species distribution shifts in the face of climate change requires a sound understanding of population diversity and local adaptations. Previous modeling has suggested that global warming will lead to increased abundance of Atlantic cod (Gadus morhua) in the ocean around Greenland, but the dynamics of earlier abundance fluctuations are not well understood. We applied a retrospective spatiotemporal population genomics approach to examine the temporal stability of cod population structure in this region and to search for signatures of divergent selection over a 78-year period spanning major demographic changes. Analyzing >900 gene-associated single nucleotide polymorphisms in 847 individuals, we identified four genetically distinct groups that exhibited varying spatial distributions with considerable overlap and mixture. The genetic composition had remained stable over decades at some spawning grounds, whereas complete population replacement was evident at others. Observations of elevated differentiation in certain genomic regions are consistent with adaptive divergence between the groups, indicating that they may respond differently to environmental variation. Significantly increased temporal changes at a subset of loci also suggest that adaptation may be ongoing. These findings illustrate the power of spatiotemporal population genomics for revealing biocomplexity in both space and time and for informing future fisheries management and conservation efforts. PMID:23789034
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Therkildsen, Nina Overgaard; Hemmer-Hansen, Jakob; Hedeholm, Rasmus Berg; Wisz, Mary S; Pampoulie, Christophe; Meldrup, Dorte; Bonanomi, Sara; Retzel, Anja; Olsen, Steffen Malskær; Nielsen, Einar Eg
2013-06-01
Accurate prediction of species distribution shifts in the face of climate change requires a sound understanding of population diversity and local adaptations. Previous modeling has suggested that global warming will lead to increased abundance of Atlantic cod (Gadus morhua) in the ocean around Greenland, but the dynamics of earlier abundance fluctuations are not well understood. We applied a retrospective spatiotemporal population genomics approach to examine the temporal stability of cod population structure in this region and to search for signatures of divergent selection over a 78-year period spanning major demographic changes. Analyzing >900 gene-associated single nucleotide polymorphisms in 847 individuals, we identified four genetically distinct groups that exhibited varying spatial distributions with considerable overlap and mixture. The genetic composition had remained stable over decades at some spawning grounds, whereas complete population replacement was evident at others. Observations of elevated differentiation in certain genomic regions are consistent with adaptive divergence between the groups, indicating that they may respond differently to environmental variation. Significantly increased temporal changes at a subset of loci also suggest that adaptation may be ongoing. These findings illustrate the power of spatiotemporal population genomics for revealing biocomplexity in both space and time and for informing future fisheries management and conservation efforts.
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The use of CPR data in fisheries research [review article
NASA Astrophysics Data System (ADS)
Corten, A.; Lindley, J. A.
2003-08-01
The Continuous Plankton Recorder (CPR) survey was initiated partly to contribute to our understanding of the variability of fish stocks and as a potential method for predicting fish distributions from the abundance and composition of the plankton. The latter objective has been superseded by technological developments in fish detection, but the former has been the subject of continuing, and in recent years expanding use of the CPR data. Examples are presented of application of the data to studies on North Sea herring, cod, mackerel, blue whiting and redfish as well as more general plankton studies relevant to fisheries research. Variations in the migration patterns of herring as well as recruitment have been related to abundances and species composition of the plankton in the CPR survey. Extensive use has been made of the CPR data in relation to cod, particularly in the development and testing of the ‘match-mismatch’ hypothesis. Advection of sufficient numbers of Calanus from the core oceanic areas of its distribution into the areas where the cod stocks occur may partly determine the success of those stocks. The analysis of the distribution and abundances of mackerel larvae in the CPR survey have shown contrasting variations between the North Sea and Celtic Sea. The expansion of the horse mackerel fishery in the north-eastern North Sea since 1987 has been related to physical events and a ‘regime shift’ in the plankton, described from CPR data. The oceanic spawning areas of the blue whiting and redfish were highlighted by the expansion of the CPR survey into the north-eastern and north-western Atlantic respectively. These results helped to focus the attention of fisheries scientists on stocks that have subsequently become the targets for commercial exploitation. The results of the CPR survey, particularly those on Calanusfinmarchicus, the phytoplankton standing stock as measured by the CPR colour index, the overall patterns of trends in plankton abundance and distributions of indicator species have been used by fisheries scientists to interpret variations in fish stocks. Generally the CPR data can be used to determine whether changes in the distributions and growth rates of fish have resulted from changes in planktonic food, changes in strength of ocean currents and distribution of water masses and to identify trends in larval abundances. With the tightening regulation of fisheries to reduce overfishing, global climate change and changing anthropogenic inputs into the sea, the unique source of information on unexploited populations in the long-term time series of the CPR survey will be of increasing value to fisheries scientists in the study of natural variability.
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NASA Astrophysics Data System (ADS)
Rijnsdorp, Adriaan D.; Dekker, Willem; Heessen, Henk J. L.
We describe the career of Professor Niels Daan at the governmental Netherlands Institute for Fisheries Research (RIVO) and analyse his role in the development of fisheries science, in the Netherlands as well as in the International Council for the Exploration of the Sea (ICES). Major contributions are (i) his research on the interactions between cod and its prey; (ii) the standardization, data base development and quality control of the ICES International Bottom Trawl Survey; (iii) his role as editor-in-chief of the ICES Journal of Marine Science; (iv) his role in stimulating new approaches and critically questioning the science behind the advice; (v) his often silent support to a wide group of young fisheries scientists.
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Selective fishing induces density-dependent growth.
Svedäng, Henrik; Hornborg, Sara
2014-06-12
Over the last decades, views on fisheries management have oscillated between alarm and trust in management progress. The predominant policy for remedying the world fishing crisis aims at maximum sustainable yield (MSY) by adjusting gear selectivity and fishing effort. Here we report a case study on how striving for higher yields from the Eastern Baltic cod stock by increasing selectivity has become exceedingly detrimental for its productivity. Although there is a successive increase in numbers of undersized fish, growth potential is severely reduced, and fishing mortality in fishable size has increased. Once density-dependent growth is introduced, the process is self-enforcing as long as the recruitment remains stable. Our findings suggest that policies focusing on maximum yield while targeting greater sizes are risky and should instead prioritize catch rates over yield. Disregarding the underlying population structure may jeopardize stock productivity, with dire consequences for the fishing industry and ecosystem structure and function.
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ERIC Educational Resources Information Center
Pollack, Susan
1995-01-01
Describes the collapse of Newfoundland's once immense northern-cod fishery in 1992 from the perspective of a family fisherman who has become an environmental activist. Discusses failures in environmental management including the overfishing of shared resources encouraged by the Canadian government and hastened by international fishing fleets and…
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A method to assess social sustainability of capture fisheries: An application to a Norwegian trawler
DOE Office of Scientific and Technical Information (OSTI.GOV)
Veldhuizen, L.J.L., E-mail: linda.veldhuizen@wur.nl; Berentsen, P.B.M.; Bokkers, E.A.M.
Social sustainability assessment of capture fisheries is, both in terms of method development and measurement, not well developed. The objective of this study, therefore, was to develop a method consisting of indicators and rubrics (i.e. categories that articulate levels of performance) to assess social sustainability of capture fisheries. This method was applied to a Norwegian trawler that targets cod and haddock in the northeast Atlantic. Based on previous research, 13 social sustainability issues were selected. To measure the state of these issues, 17 process and outcome indicators were determined. To interpret indicator values, rubrics were developed for each indicator, usingmore » standards set by international conventions or data retrieved from national statistics, industry agreements or scientific publications that explore rubric scales. The indicators and rubrics were subsequently used in a social sustainability assessment of a Norwegian trawler. This assessment indicated that overall, social sustainability of this trawler is relatively high, with high rubric scores, for example, for worker safety, provisions aboard for the crew and companies' salary levels. The assessment also indicated that the trawler could improve on healthy working environment, product freshness and fish welfare during capture. This application demonstrated that our method provides insight into social sustainability at the level of the vessel and can be used to identify potential room for improvement. This method is also promising for social sustainability assessment of other capture fisheries. - Highlights: • A method was developed for social sustainability assessment of capture fisheries. • This method entailed determining outcome and process indicators for important issues. • To interpret indicator values, a rubric was developed for each indicator. • Use of this method gives insight into social sustainability and improvement options. • This method is promising for social sustainability assessment of capture fisheries.« less
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Marine mammals' influence on ecosystem processes affecting fisheries in the Barents Sea is trivial.
Corkeron, Peter J
2009-04-23
Some interpretations of ecosystem-based fishery management include culling marine mammals as an integral component. The current Norwegian policy on marine mammal management is one example. Scientific support for this policy includes the Scenario Barents Sea (SBS) models. These modelled interactions between cod, Gadus morhua, herring, Clupea harengus, capelin, Mallotus villosus and northern minke whales, Balaenoptera acutorostrata. Adding harp seals Phoca groenlandica into this top-down modelling approach resulted in unrealistic model outputs. Another set of models of the Barents Sea fish-fisheries system focused on interactions within and between the three fish populations, fisheries and climate. These model key processes of the system successfully. Continuing calls to support the SBS models despite their failure suggest a belief that marine mammal predation must be a problem for fisheries. The best available scientific evidence provides no justification for marine mammal culls as a primary component of an ecosystem-based approach to managing the fisheries of the Barents Sea.
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Spatial ecology of coastal Atlantic cod Gadus morhua associated with parasite load.
Aalvik, I M; Moland, E; Olsen, E M; Stenseth, N C
2015-08-01
Acoustic tags and receivers were used to investigate the spatial ecology of coastal Atlantic cod Gadus morhua (n = 32, mean fork length: 50 cm, range: 33-80 cm) on the Norwegian Skagerrak coast in 2012. Monthly home ranges (HR), swimming activity and depth use varied considerably among individuals and through the months of June, July and August. HR sizes for the period ranged from 0.25 to 5.20 km2 (mean = 2.30 km2. Two thirds of the tagged G. morhua were infected with black spot disease Cryptocotyle lingua parasites; these fish had larger HRs and occupied deeper water compared with non-infected fish. The infected fish also tended to be more active in terms of horizontal swimming. From an ecological and evolutionary perspective, any environmental change that modifies G. morhua behaviour may therefore also alter the parasite load of the population, and its conservation and fishery status. © 2015 The Fisheries Society of the British Isles.
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Supply and demand drive a critical transition to dysfunctional fisheries.
Fryxell, John M; Hilborn, Ray; Bieg, Carling; Turgeon, Katrine; Caskenette, Amanda; McCann, Kevin S
2017-11-14
There is growing awareness of the need for fishery management policies that are robust to changing environmental, social, and economic pressures. Here we use conventional bioeconomic theory to demonstrate that inherent biological constraints combined with nonlinear supply-demand relationships can generate threshold effects due to harvesting. As a result, increases in overall demand due to human population growth or improvement in real income would be expected to induce critical transitions from high-yield/low-price fisheries to low-yield/high-price fisheries, generating severe strains on social and economic systems as well as compromising resource conservation goals. As a proof of concept, we show that key predictions of the critical transition hypothesis are borne out in oceanic fisheries (cod and pollock) that have experienced substantial increase in fishing pressure over the past 60 y. A hump-shaped relationship between price and historical harvest returns, well demonstrated in these empirical examples, is particularly diagnostic of fishery degradation. Fortunately, the same heuristic can also be used to identify reliable targets for fishery restoration yielding optimal bioeconomic returns while safely conserving resource abundance. Copyright © 2017 the Author(s). Published by PNAS.
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Mechanistic insights into the effects of climate change on larval cod.
Kristiansen, Trond; Stock, Charles; Drinkwater, Kenneth F; Curchitser, Enrique N
2014-05-01
Understanding the biophysical mechanisms that shape variability in fisheries recruitment is critical for estimating the effects of climate change on fisheries. In this study, we used an Earth System Model (ESM) and a mechanistic individual-based model (IBM) for larval fish to analyze how climate change may impact the growth and survival of larval cod in the North Atlantic. We focused our analysis on five regions that span the current geographical range of cod and are known to contain important spawning populations. Under the SRES A2 (high emissions) scenario, the ESM-projected surface ocean temperatures are expected to increase by >1 °C for 3 of the 5 regions, and stratification is expected to increase at all sites between 1950-1999 and 2050-2099. This enhanced stratification is projected to decrease large (>5 μm ESD) phytoplankton productivity and mesozooplankton biomass at all 5 sites. Higher temperatures are projected to increase larval metabolic costs, which combined with decreased food resources will reduce larval weight, increase the probability of larvae dying from starvation and increase larval exposure to visual and invertebrate predators at most sites. If current concentrations of piscivore and invertebrate predators are maintained, larval survival is projected to decrease at all five sites by 2050-2099. In contrast to past observed responses to climate variability in which warm anomalies led to better recruitment in cold-water stocks, our simulations indicated that reduced prey availability under climate change may cause a reduction in larval survival despite higher temperatures in these regions. In the lower prey environment projected under climate change, higher metabolic costs due to higher temperatures outweigh the advantages of higher growth potential, leading to negative effects on northern cod stocks. Our results provide an important first large-scale assessment of the impacts of climate change on larval cod in the North Atlantic. © 2013 John Wiley & Sons Ltd.
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New England Cod Collapse and the Climate.
Meng, Kyle C; Oremus, Kimberly L; Gaines, Steven D
2016-01-01
To improve fishery management, there is an increasing need to understand the long-term consequences of natural and anthropogenic climate variability for ecological systems. New England's iconic cod populations have been in decline for several decades and have recently reached unprecedented lows. We find that 17% of the overall decline in Gulf of Maine cod biomass since 1980 can be attributed to positive phases of the North Atlantic Oscillation (NAO). This is a consequence of three results: i) a 1-unit increase in the NAO winter index is associated with a 17% decrease in the spring biomass of age-1 cod the following year; ii) this NAO-driven decrease persists as the affected cohort matures; iii) fishing practices appear to exacerbate NAO's direct biological effect such that, since 1913, a 1-unit increase in the NAO index lowers subsequent cod catch for up to 19 years. The Georges Bank cod stock displays similar patterns. Because we statistically detect a delay between the NAO and subsequent declines in adult biomass, our findings imply that observed current NAO conditions can be used in stock forecasts, providing lead time for adaptive policy. More broadly, our approach can inform forecasting efforts for other fish populations strongly affected by natural and anthropogenic climatic variation.
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New England Cod Collapse and the Climate
Meng, Kyle C.; Oremus, Kimberly L.; Gaines, Steven D.
2016-01-01
To improve fishery management, there is an increasing need to understand the long-term consequences of natural and anthropogenic climate variability for ecological systems. New England’s iconic cod populations have been in decline for several decades and have recently reached unprecedented lows. We find that 17% of the overall decline in Gulf of Maine cod biomass since 1980 can be attributed to positive phases of the North Atlantic Oscillation (NAO). This is a consequence of three results: i) a 1-unit increase in the NAO winter index is associated with a 17% decrease in the spring biomass of age-1 cod the following year; ii) this NAO-driven decrease persists as the affected cohort matures; iii) fishing practices appear to exacerbate NAO’s direct biological effect such that, since 1913, a 1-unit increase in the NAO index lowers subsequent cod catch for up to 19 years. The Georges Bank cod stock displays similar patterns. Because we statistically detect a delay between the NAO and subsequent declines in adult biomass, our findings imply that observed current NAO conditions can be used in stock forecasts, providing lead time for adaptive policy. More broadly, our approach can inform forecasting efforts for other fish populations strongly affected by natural and anthropogenic climatic variation. PMID:27463967
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77 FR 42278 - New England Fishery Management Council; Public Meeting
Federal Register 2010, 2011, 2012, 2013, 2014
2012-07-18
... issues that may be incorporated into the framework, such as issues related to Georges Bank yellowtail... expected to receive a preliminary report on the recent assessments of Eastern Georges Bank cod and haddock, and Georges Bank yellowtail flounder that were conducted by the Transboundary Resource Assessment...
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Federal Register 2010, 2011, 2012, 2013, 2014
2010-09-02
... increase interactions with protected species. However, if additional nets result in greater efficiency... throughout the year, thus potentially reducing interactions with protected species. Sector vessels utilizing... Port Clyde Community Groundfish Sector, the GB Cod Fixed Gear Sector and the Tri-State Sector. 2...
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NASA Astrophysics Data System (ADS)
Holsman, Kirstin K.; Ianelli, James; Aydin, Kerim; Punt, André E.; Moffitt, Elizabeth A.
2016-12-01
Multi-species statistical catch at age models (MSCAA) can quantify interacting effects of climate and fisheries harvest on species populations, and evaluate management trade-offs for fisheries that target several species in a food web. We modified an existing MSCAA model to include temperature-specific growth and predation rates and applied the modified model to three fish species, walleye pollock (Gadus chalcogrammus), Pacific cod (Gadus macrocephalus) and arrowtooth flounder (Atheresthes stomias), from the eastern Bering Sea (USA). We fit the model to data from 1979 through 2012, with and without trophic interactions and temperature effects, and use projections to derive single- and multi-species biological reference points (BRP and MBRP, respectively) for fisheries management. The multi-species model achieved a higher over-all goodness of fit to the data (i.e. lower negative log-likelihood) for pollock and Pacific cod. Variability from water temperature typically resulted in 5-15% changes in spawning, survey, and total biomasses, but did not strongly impact recruitment estimates or mortality. Despite this, inclusion of temperature in projections did have a strong effect on BRPs, including recommended yield, which were higher in single-species models for Pacific cod and arrowtooth flounder that included temperature compared to the same models without temperature effects. While the temperature-driven multi-species model resulted in higher yield MBPRs for arrowtooth flounder than the same model without temperature, we did not observe the same patterns in multi-species models for pollock and Pacific cod, where variability between harvest scenarios and predation greatly exceeded temperature-driven variability in yield MBRPs. Annual predation on juvenile pollock (primarily cannibalism) in the multi-species model was 2-5 times the annual harvest of adult fish in the system, thus predation represents a strong control on population dynamics that exceeds temperature-driven changes to growth and is attenuated through harvest-driven reductions in predator populations. Additionally, although we observed differences in spawning biomasses at the accepted biological catch (ABC) proxy between harvest scenarios and single- and multi-species models, discrepancies in spawning stock biomass estimates did not translate to large differences in yield. We found that multi-species models produced higher estimates of combined yield for aggregate maximum sustainable yield (MSY) targets than single species models, but were more conservative than single-species models when individual MSY targets were used, with the exception of scenarios where minimum biomass thresholds were imposed. Collectively our results suggest that climate and trophic drivers can interact to affect MBRPs, but for prey species with high predation rates, trophic- and management-driven changes may exceed direct effects of temperature on growth and predation. Additionally, MBRPs are not inherently more conservative than single-species BRPs. This framework provides a basis for the application of MSCAA models for tactical ecosystem-based fisheries management decisions under changing climate conditions.
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NASA Astrophysics Data System (ADS)
Misund, Ole Arve; Heggland, Kristin; Skogseth, Ragnheid; Falck, Eva; Gjøsæter, Harald; Sundet, Jan; Watne, Jens; Lønne, Ole Jørgen
2016-09-01
The Svalbard archipelago in the High Arctic is influenced by cold Arctic water masses from the north-east and the warm West Spitsbergen Current flowing northwards along its western coast. The eastern waters and the fjords are normally frozen during the winter months, while the coastal waters west of the archipelago remain open. Norwegian fishers have been harvesting from Svalbard waters for decades and detailed records of catches exists from 1980 onwards. We analyze the catch records from the Svalbard zone (approximately ICES area IIb). The large fishery for capelin in summer yielding annual catches up to 737 000 tons was closed by a Norwegian fishery regulation in the mid nineteen nineties. Demersal fisheries have been continuous, and the results clearly indicate a northward trend in landings of Northeast Arctic cod, haddock, ling and Atlantic halibut. Fisheries of Northern shrimp have been more variable and shown no clear geographic trends. A "gold rush" fishery for scallops north of Svalbard lasted for about 10 years (1986-1995) only, and ended due to low profitably. These results are discussed in relation to the possibility of further northward extension of fisheries subjected to climate change.
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Federal Register 2010, 2011, 2012, 2013, 2014
2011-03-08
... Catcher Vessels Less Than 60 Feet (18.3 m) Length Overall Using Jig or Hook-and-Line Gear in the Bogoslof... less than 60 feet (18.3 m) length overall (LOA) using jig or hook-and-line gear in the Bogoslof Pacific...
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Federal Register 2010, 2011, 2012, 2013, 2014
2010-02-26
... Vessels Less Than 60 feet (18.3 m) Length Overall Using Jig or Hook-and-Line Gear in the Bogoslof Pacific... less than 60 feet (18.3 m) length overall (LOA) using jig or hook-and-line gear in the Bogoslof Pacific...
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50 CFR 679.64 - Harvesting sideboard limits in other fisheries.
Code of Federal Regulations, 2010 CFR
2010-10-01
.../processors be calculated? Except for Aleutian Islands pollock and BSAI Pacific cod, the Regional... group in which a TAC is specified for an area or subarea of the BSAI as follows: (i) Aleutian Islands Pacific ocean perch. (A) The Aleutian Islands Pacific ocean perch harvest limit will be equal to the 1996...
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Federal Register 2010, 2011, 2012, 2013, 2014
2013-12-10
... trend for pollock, Pacific cod, deep-water flatfish, Pacific ocean perch, northern rockfish, shortraker..., shallow-water flatfish, rex sole, arrowtooth flounder, flathead sole, rougheye rockfish, demersal shelf... include the TACs for shallow-water flatfish in the West Yakutat and Southeast Outside Districts of the GOA...
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Federal Register 2010, 2011, 2012, 2013, 2014
2012-10-17
... published on September 26, 2012, modifying equipment and operational requirements for freezer longliners... Pacific cod at sea with hook-and-line gear in the Bering Sea and Aleutian Islands Management Area (BSAI... modifying equipment and operational requirements for freezer longliners published September 26, 2012, NMFS...
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NASA Astrophysics Data System (ADS)
Morissette, Lyne; Pedersen, Torstein; Nilsen, Marianne
2009-04-01
The Sørfjord, Norway, and the Gulf of St. Lawrence, Canada, are two sub-arctic ecosystems with similar trophic structure. However, in the Gulf of St. Lawrence, severe exploitation of groundfish stocks has lead to important shifts in the trophic structure. In the Sørfjord, the situation is different: fishing pressure is much lighter. Our hypothesis is that overexploitation leads to changes in the trophic structure and severely alters the resilience of ecosystems. Based on the same modelling approach ( Ecopath with Ecosim) the food web structure was compared, using different ecosystem indicators. Patterns of food web structure and trophodynamics were contrasted. Cod was the keystone species in both ecosystems, and forage fish were also important. Even after similar environmental changes in both ecosystems, and after a reduction of fishing pressure in the Gulf of St. Lawrence, there is no recovery of cod stocks in this ecosystem. In the Sørfjord, after different perturbations (but not from the fishery), the ecosystem seems to return to its equilibrium.
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Elliott, S A M; Ahti, P A; Heath, M R; Turrell, W R; Bailey, D M
2016-08-01
Stereo-video scuba transects were conducted during daylight hours from June to September 2013 within a proposed marine protected area (MPA) in the Firth of Clyde, west of Scotland. More juvenile Atlantic cod Gadus morhua of fork length (LF ) range 6-11 cm were observed in substrata containing mixed gravel, including maerl, than in boulder-cobble substrata with high algal cover, or sand with low density seagrass. Community composition was significantly different between substratum types. A decrease in G. morhua abundance was observed over the period of data collection. Over time, mean and variance in G. morhua LF increased, indicating multiple recruitment events. Protecting mixed gravel substrata could be a beneficial management measure to support the survival and recruitment of juvenile G. morhua; other substrata might be important at night given their diel migratory behaviour. Stereo-video cameras provide a useful non-destructive fisheries-independent method to monitor species abundance and length measurements. © 2016 The Authors. Journal of Fish Biology published by John Wiley & Sons Ltd on behalf of The Fisheries Society of the British Isles.
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Temporal Dynamics of Top Predators Interactions in the Barents Sea
Durant, Joël M.; Skern-Mauritzen, Mette; Krasnov, Yuri V.; Nikolaeva, Natalia G.; Lindstrøm, Ulf; Dolgov, Andrey
2014-01-01
The Barents Sea system is often depicted as a simple food web in terms of number of dominant feeding links. The most conspicuous feeding link is between the Northeast Arctic cod Gadus morhua, the world's largest cod stock which is presently at a historical high level, and capelin Mallotus villosus. The system also holds diverse seabird and marine mammal communities. Previous diet studies may suggest that these top predators (cod, bird and sea mammals) compete for food particularly with respect to pelagic fish such as capelin and juvenile herring (Clupea harengus), and krill. In this paper we explored the diet of some Barents Sea top predators (cod, Black-legged kittiwake Rissa tridactyla, Common guillemot Uria aalge, and Minke whale Balaenoptera acutorostrata). We developed a GAM modelling approach to analyse the temporal variation diet composition within and between predators, to explore intra- and inter-specific interactions. The GAM models demonstrated that the seabird diet is temperature dependent while the diet of Minke whale and cod is prey dependent; Minke whale and cod diets depend on the abundance of herring and capelin, respectively. There was significant diet overlap between cod and Minke whale, and between kittiwake and guillemot. In general, the diet overlap between predators increased with changes in herring and krill abundances. The diet overlap models developed in this study may help to identify inter-specific interactions and their dynamics that potentially affect the stocks targeted by fisheries. PMID:25365430
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Spawning stock and recruitment in North Sea cod shaped by food and climate
Olsen, Esben Moland; Ottersen, Geir; Llope, Marcos; Chan, Kung-Sik; Beaugrand, Grégory; Stenseth, Nils Chr.
2011-01-01
In order to provide better fisheries management and conservation decisions, there is a need to discern the underlying relationship between the spawning stock and recruitment of marine fishes, a relationship which is influenced by the environmental conditions. Here, we demonstrate how the environmental conditions (temperature and the food availability for fish larvae) influence the stock–recruitment relationship and indeed what kind of stock–recruitment relationship we might see under different environmental conditions. Using unique zooplankton data from the Continuous Plankton Recorder, we find that food availability (i.e. zooplankton) in essence determines which model applies for the once large North Sea cod (Gadus morhua) stock. Further, we show that recruitment is strengthened during cold years and weakened during warm years. Our combined model explained 45 per cent of the total variance in cod recruitment, while the traditional Ricker and Beverton–Holt models only explained about 10 per cent. Specifically, our approach predicts that a full recovery of the North Sea cod stock might not be expected until the environment becomes more favourable. PMID:20810442
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NASA Astrophysics Data System (ADS)
Aschan, Michaela; Ingvaldsen, Randi
2009-10-01
The shrimp spawn in autumn, and the females carry their eggs as out roe until spring when the larvae hatch. Within a period of 2 months the shrimp larvae settle to the bottom. It has been claimed that the year-class strength probably is determined during the larval phase. Today's assessment and forecast of the shrimp stock productivity and potential fishing yields are weak. This is partly due to poor knowledge on population dynamics from hatching until the shrimp are caught in the fishery at the age of 3 or 4 years. We, therefore, here identify the most important abiotic and biotic factors that affect recruitment in addition to spawning stock biomass. Since 1995, a net attached to the underbelly of the survey trawl used at the annual cruise in the Barents Sea has caught juvenile shrimp. The abundance of settled shrimp larvae varies in time and space. The recruitment to the fishery has been quite stable with the exception of the 1996 year-class, which was observed as 1-year-olds but has not been registered since. The temporal pattern of the three youngest year-classes is studied in relation to abiotic factors such as sea temperature, ice index and North Atlantic Oscillation, as well as biotic factors such as spawning stock biomass and presence of copepods, euphausiids and predating cod. Recruitment indices and factors identified by the Spearmann correlation to be significantly correlated with recruitment were used as input in a principal component analysis (PCA) and a generalized additive model (GAM) was applied. Abundance of 1-year-old shrimp is positively correlated to spawning stock biomass the previous year and to temperature of the previous winter, and negatively correlated with the number of 1-year-old cod. Two-year-old shrimp show significant correlation with temperature, whereas there is a strong negative correlation with euphausiids. Three-year-old shrimp are significantly correlated with the number of 2-year-old shrimp the previous year but negatively correlated to temperature at sampling time. This is probably due to less overlap with the main predator cod when cold. Ricker functions indicate an increased density-dependent mortality with age. When predicting the recruitment of shrimp to the fishery, the spawning stock biomass, the abundance of cod and euphausiids, as well as the temperature should be included.
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Climate change and fishing: a century of shifting distribution in North Sea cod
Engelhard, Georg H; Righton, David A; Pinnegar, John K
2014-01-01
Globally, spatial distributions of fish stocks are shifting but although the role of climate change in range shifts is increasingly appreciated, little remains known of the likely additional impact that high levels of fishing pressure might have on distribution. For North Sea cod, we show for the first time and in great spatial detail how the stock has shifted its distribution over the past 100 years. We digitized extensive historical fisheries data from paper charts in UK government archives and combined these with contemporary data to a time-series spanning 1913–2012 (excluding both World Wars). New analysis of old data revealed that the current distribution pattern of cod – mostly in the deeper, northern- and north-easternmost parts of the North Sea – is almost opposite to that during most of the Twentieth Century – mainly concentrated in the west, off England and Scotland. Statistical analysis revealed that the deepening, northward shift is likely attributable to warming; however, the eastward shift is best explained by fishing pressure, suggestive of significant depletion of the stock from its previous stronghold, off the coasts of England and Scotland. These spatial patterns were confirmed for the most recent 3½ decades by data from fisheries-independent surveys, which go back to the 1970s. Our results demonstrate the fundamental importance of both climate change and fishing pressure for our understanding of changing distributions of commercially exploited fish. PMID:24375860
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Federal Register 2010, 2011, 2012, 2013, 2014
2010-12-08
... for 2011 and 2012 that are equal to proposed ABCs for pollock, deep-water flatfish, rex sole... certain species: Pacific cod, flathead sole, shallow-water flatfish, arrowtooth flounder, and other... that the ABC is not exceeded. The flathead sole, shallow-water flatfish, and arrowtooth flounder TACs...
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Federal Register 2010, 2011, 2012, 2013, 2014
2013-01-03
... to the 2013 Bering Sea and Aleutian Islands Pollock, Atka Mackerel, and Pacific Cod Total Allowable... is adjusting the 2013 total allowable catch (TAC) amounts for the Bering Sea and Aleutian Islands....), December 28, 2012, until the effective date of the final 2013 and 2014 harvest specifications for BSAI...
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Federal Register 2010, 2011, 2012, 2013, 2014
2013-01-03
... to the 2013 Gulf of Alaska Pollock and Pacific Cod Total Allowable Catch Amounts AGENCY: National...: Temporary rule; inseason adjustment; request for comments. SUMMARY: NMFS is adjusting the 2013 total... (A.l.t.), December 28, 2012, until the effective date of the final 2013 and 2014 harvest...
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Molfese, Carlotta; Beare, Doug; Hall-Spencer, Jason M
2014-01-01
The worldwide depletion of major fish stocks through intensive industrial fishing is thought to have profoundly altered the trophic structure of marine ecosystems. Here we assess changes in the trophic structure of the English Channel marine ecosystem using a 90-year time-series (1920-2010) of commercial fishery landings. Our analysis was based on estimates of the mean trophic level (mTL) of annual landings and the Fishing-in-Balance index (FiB). Food webs of the Channel ecosystem have been altered, as shown by a significant decline in the mTL of fishery landings whilst increases in the FiB index suggest increased fishing effort and fishery expansion. Large, high trophic level species (e.g. spurdog, cod, ling) have been increasingly replaced by smaller, low trophic level fish (e.g. small spotted catsharks) and invertebrates (e.g. scallops, crabs and lobster). Declining trophic levels in fisheries catches have occurred worldwide, with fish catches progressively being replaced by invertebrates. We argue that a network of fisheries closures would help rebalance the trophic status of the Channel and allow regeneration of marine ecosystems.
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Local overfishing may be avoided by examining parameters of a spatio-temporal model
Shackell, Nancy; Mills Flemming, Joanna
2017-01-01
Spatial erosion of stock structure through local overfishing can lead to stock collapse because fish often prefer certain locations, and fisheries tend to focus on those locations. Fishery managers are challenged to maintain the integrity of the entire stock and require scientific approaches that provide them with sound advice. Here we propose a Bayesian hierarchical spatio-temporal modelling framework for fish abundance data to estimate key parameters that define spatial stock structure: persistence (similarity of spatial structure over time), connectivity (coherence of temporal pattern over space), and spatial variance (variation across the seascape). The consideration of these spatial parameters in the stock assessment process can help identify the erosion of structure and assist in preventing local overfishing. We use Atlantic cod (Gadus morhua) in eastern Canada as a case study an examine the behaviour of these parameters from the height of the fishery through its collapse. We identify clear signals in parameter behaviour under circumstances of destructive stock erosion as well as for recovery of spatial structure even when combined with a non-recovery in abundance. Further, our model reveals the spatial pattern of areas of high and low density persists over the 41 years of available data and identifies the remnant patches. Models of this sort are crucial to recovery plans if we are to identify and protect remaining sources of recolonization for Atlantic cod. Our method is immediately applicable to other exploited species. PMID:28886179
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Local overfishing may be avoided by examining parameters of a spatio-temporal model.
Carson, Stuart; Shackell, Nancy; Mills Flemming, Joanna
2017-01-01
Spatial erosion of stock structure through local overfishing can lead to stock collapse because fish often prefer certain locations, and fisheries tend to focus on those locations. Fishery managers are challenged to maintain the integrity of the entire stock and require scientific approaches that provide them with sound advice. Here we propose a Bayesian hierarchical spatio-temporal modelling framework for fish abundance data to estimate key parameters that define spatial stock structure: persistence (similarity of spatial structure over time), connectivity (coherence of temporal pattern over space), and spatial variance (variation across the seascape). The consideration of these spatial parameters in the stock assessment process can help identify the erosion of structure and assist in preventing local overfishing. We use Atlantic cod (Gadus morhua) in eastern Canada as a case study an examine the behaviour of these parameters from the height of the fishery through its collapse. We identify clear signals in parameter behaviour under circumstances of destructive stock erosion as well as for recovery of spatial structure even when combined with a non-recovery in abundance. Further, our model reveals the spatial pattern of areas of high and low density persists over the 41 years of available data and identifies the remnant patches. Models of this sort are crucial to recovery plans if we are to identify and protect remaining sources of recolonization for Atlantic cod. Our method is immediately applicable to other exploited species.
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The role of a dominant predator in shaping biodiversity over space and time in a marine ecosystem.
Ellingsen, Kari E; Anderson, Marti J; Shackell, Nancy L; Tveraa, Torkild; Yoccoz, Nigel G; Frank, Kenneth T
2015-09-01
1. Exploitation of living marine resources has resulted in major changes to populations of targeted species and functional groups of large-bodied species in the ocean. However, the effects of overfishing and collapse of large top predators on the broad-scale biodiversity of oceanic ecosystems remain largely unexplored. 2. Populations of the Atlantic cod (Gadus morhua) were overfished and several collapsed in the early 1990s across Atlantic Canada, providing a unique opportunity to study potential ecosystem-level effects of the reduction of a dominant predator on fish biodiversity, and to identify how such effects might interact with other environmental factors, such as changes in climate, over time. 3. We combined causal modelling with model selection and multimodel inference to analyse 41 years of fishery-independent survey data (1970-2010) and quantify ecosystem-level effects of overfishing and climate variation on the biodiversity of fishes across a broad area (172 000 km(2) ) of the Scotian Shelf. 4. We found that alpha and beta diversity increased with decreases in cod occurrence; fish communities were less homogeneous and more variable in systems where cod no longer dominated. These effects were most pronounced in the colder north-eastern parts of the Scotian Shelf. 5. Our results provide strong evidence that intensive harvesting (and collapse) of marine apex predators can have large impacts on biodiversity, with far-reaching consequences for ecological stability across an entire ecosystem. © 2015 The Authors. Journal of Animal Ecology published by John Wiley & Sons Ltd on behalf of British Ecological Society.
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NASA Astrophysics Data System (ADS)
Savenkoff, Claude; Castonguay, Martin; Chabot, Denis; Hammill, Mike O.; Bourdages, Hugo; Morissette, Lyne
2007-07-01
Mass-balance models have been constructed using inverse methodology for the northern Gulf of St. Lawrence for the mid-1980s, the mid-1990s, and the early 2000s to describe ecosystem structure, trophic group interactions, and the effects of fishing and predation on the ecosystem for each time period. Our analyses indicate that the ecosystem structure shifted dramatically from one previously dominated by demersal (cod, redfish) and small-bodied forage (e.g., capelin, mackerel, herring, shrimp) species to one now dominated by small-bodied forage species. Overfishing removed a functional group in the late 1980s, large piscivorous fish (primarily cod and redfish), which has not recovered 14 years after the cessation of heavy fishing. This has left only marine mammals as top predators during the mid-1990s, and marine mammals and small Greenland halibut during the early 2000s. Predation by marine mammals on fish increased from the mid-1980s to the early 2000s while predation by large fish on fish decreased. Capelin and shrimp, the main prey in each period, showed an increase in biomass over the three periods. A switch in the main predators of capelin from cod to marine mammals occurred, while Greenland halibut progressively replaced cod as shrimp predators. Overfishing influenced community structure directly through preferential removal of larger-bodied fishes and indirectly through predation release because larger-bodied fishes exerted top-down control upon other community species or competed with other species for the same prey. Our modelling estimates showed that a change in predation structure or flows at the top of the trophic system led to changes in predation at all lower trophic levels in the northern Gulf of St. Lawrence. These changes represent a case of fishery-induced regime shift.
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Federal Register 2010, 2011, 2012, 2013, 2014
2011-03-01
.... The Council recommended TACs for 2011 and 2012 that are equal to ABCs for pollock, deep-water flatfish... less than the ABCs for Pacific cod, flathead sole, shallow-water flatfish, arrowtooth flounder, other...-water flatfish, and arrowtooth flounder TACs are set to conserve the halibut PSC limit for use in other...
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Federal Register 2010, 2011, 2012, 2013, 2014
2012-04-02
... Catcher Vessels Using Trawl Gear in the Central Regulatory Area of the Gulf of Alaska AGENCY: National... (CVs) using trawl gear in the Central Regulatory Area of the Gulf of Alaska (GOA). This action is... apportioned to CVs using trawl gear in the Central Regulatory Area of the GOA. DATES: Effective 1200 hrs...
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Federal Register 2010, 2011, 2012, 2013, 2014
2011-03-30
... Vessels Using Trawl Gear in the Bering Sea and Aleutian Islands Management Area AGENCY: National Marine... using trawl gear in the Bering Sea and Aleutian Islands management area (BSAI). This action is necessary... for catcher vessels using trawl gear in the BSAI. DATES: Effective 1200 hrs, Alaska local time (A.l.t...
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Federal Register 2010, 2011, 2012, 2013, 2014
2013-02-20
... Catcher Vessels Using Trawl Gear in the Western Regulatory Area of the Gulf of Alaska AGENCY: National... (CVs) using trawl gear in the Western Regulatory Area of the Gulf of Alaska (GOA). This action is... apportioned to CVs using trawl gear in the Western Regulatory Area of the GOA. DATES: Effective 1200 hours...
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Federal Register 2010, 2011, 2012, 2013, 2014
2010-04-01
... Vessels Using Trawl Gear in the Bering Sea and Aleutian Islands Management Area AGENCY: National Marine... using trawl gear in the Bering Sea and Aleutian Islands management area (BSAI). This action is necessary... for catcher vessels using trawl gear in the BSAI. DATES: Effective 1200 hrs, Alaska local time (A.l.t...
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Federal Register 2010, 2011, 2012, 2013, 2014
2012-03-05
... Catcher Vessels Using Trawl Gear in the Bering Sea and Aleutian Islands Management Area AGENCY: National... using trawl gear in the Bering Sea and Aleutian Islands management area (BSAI). This action is necessary... vessels using trawl gear in the BSAI. After the effective date of this closure the maximum retainable...
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Federal Register 2010, 2011, 2012, 2013, 2014
2012-02-27
... Vessels Using Trawl Gear in the Western Regulatory Area of the Gulf of Alaska AGENCY: National Marine... (CVs) using trawl gear in the Western Regulatory Area of the Gulf of Alaska (GOA). This action is... apportioned to CVs using trawl gear in the Western Regulatory Area of the GOA. DATES: Effective 1200 hrs...
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Federal Register 2010, 2011, 2012, 2013, 2014
2011-04-05
... Catcher Vessels Using Trawl Gear in the Bering Sea and Aleutian Islands Management Area AGENCY: National... using trawl gear in the Bering Sea and Aleutian Islands management area (BSAI). This action is necessary... for catcher vessels using trawl gear in the BSAI. DATES: Effective 1200 hrs, Alaska local time (A.l.t...
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Federal Register 2010, 2011, 2012, 2013, 2014
2013-03-27
... Catcher Vessels Using Trawl Gear in the Central Regulatory Area of the Gulf of Alaska AGENCY: National... (CVs) using trawl gear in the Central Regulatory Area of the Gulf of Alaska (GOA). This action is... apportioned to CVs using trawl gear in the Central Regulatory Area of the GOA. DATES: Effective 1200 hrs...
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Federal Register 2010, 2011, 2012, 2013, 2014
2010-03-16
... Vessels Using Trawl Gear in the Bering Sea and Aleutian Islands Management Area AGENCY: National Marine... using trawl gear in the Bering Sea and Aleutian Islands management area (BSAI). This action is necessary... for catcher vessels using trawl gear in the BSAI. DATES: Effective 1200 hrs, Alaska local time (A.l.t...
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Federal Register 2010, 2011, 2012, 2013, 2014
2013-03-12
... Catcher Vessels Using Trawl Gear in the Bering Sea and Aleutian Islands Management Area AGENCY: National... using trawl gear in the Bering Sea and Aleutian Islands management area (BSAI). This action is necessary... catcher vessels using trawl gear in the BSAI. After the effective date of this closure the maximum...
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Behrens, J W; Seth, H; Axelsson, M; Buchmann, K
2014-05-01
The parasitic copepod Lernaeocera branchialis had a negative effect on cardiorespiratory function in Atlantic cod Gadus morhua such that it caused pronounced cardiac dysfunction with irregular rhythm and reduced stroke amplitude compared with uninfected fish. In addition, parasite infection depressed the postprandial cardiac output and oxygen consumption. © 2014 The Fisheries Society of the British Isles.
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Federal Register 2010, 2011, 2012, 2013, 2014
2010-12-23
... (GB) when fishing under a groundfish/monkfish DAS; (6) limits on the number of hooks that may be... groundfish/monkfish DAS; (7) limits on the number of hooks that may be fished; and (8) DAS Leasing Program.... 7. Limitation on the Number of Hooks That May Be Fished The GB Cod Fixed Gear Sector was granted an...
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ERIC Educational Resources Information Center
Clover, Darlene E.
2007-01-01
Due to a moratorium on the cod fishery in 1992, small, isolated coastal villages in Newfoundland suffer increasing unemployment, health problems and threats of re-location by the government. In the hopes of addressing some of these problems, the Burgeo Broadcasting System (BBS) placed video-conferencing and broad-band internet into five small…
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Climate change and fishing: a century of shifting distribution in North Sea cod.
Engelhard, Georg H; Righton, David A; Pinnegar, John K
2014-08-01
Globally, spatial distributions of fish stocks are shifting but although the role of climate change in range shifts is increasingly appreciated, little remains known of the likely additional impact that high levels of fishing pressure might have on distribution. For North Sea cod, we show for the first time and in great spatial detail how the stock has shifted its distribution over the past 100 years. We digitized extensive historical fisheries data from paper charts in UK government archives and combined these with contemporary data to a time-series spanning 1913-2012 (excluding both World Wars). New analysis of old data revealed that the current distribution pattern of cod - mostly in the deeper, northern- and north-easternmost parts of the North Sea - is almost opposite to that during most of the Twentieth Century - mainly concentrated in the west, off England and Scotland. Statistical analysis revealed that the deepening, northward shift is likely attributable to warming; however, the eastward shift is best explained by fishing pressure, suggestive of significant depletion of the stock from its previous stronghold, off the coasts of England and Scotland. These spatial patterns were confirmed for the most recent 3 1/2 decades by data from fisheries-independent surveys, which go back to the 1970s. Our results demonstrate the fundamental importance of both climate change and fishing pressure for our understanding of changing distributions of commercially exploited fish. © 2013 Crown copyright. Global Change Biology published by John Wiley & Sons Ltd. This article is published with the permission of the Controller of HMSO and the Queen's Printer for Scotland.
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NASA Astrophysics Data System (ADS)
Rijnsdorp, A. D.; Daan, N.; Dekker, W.; Poos, J. J.; Van Densen, W. L. T.
2007-02-01
Many flatfish species are caught in mixed demersal trawl fisheries and managed by Total Allowable Catch (TAC). Despite decades of fisheries management, several major stocks are severely depleted. Using the Common Fisheries Policy (CFP) as an example, the failure of mixed-fisheries management is analysed by focussing on: the management system; the role of science; the role of managers and politicians; the response of fisheries to management. Failure of the CFP management could be ascribed to: incorrect management advice owing to bias in stock assessments; the tendency of politicians to set the TAC well above the recommended level; and non-compliance of the fisheries with the management regulations. We conclude that TAC management, although apparently successful in some single-species fisheries, inevitably leads to unsustainable exploitation of stocks caught in mixed demersal fisheries as it promotes discarding of over-quota catch and misreporting of catches, thereby corrupting the basis of the scientific advice and increasing the risk of stock collapse. This failure in mixed demersal fisheries has resulted in the loss of credibility of both scientists and managers, and has undermined the support of fishermen for management regulations. An approach is developed to convert the TAC system into a system that controls the total allowable effort (TAE). The approach takes account of the differences in catch efficiency between fleets as well as seasonal changes in the distribution of the target species and can also be applied in the recovery plans for rebuilding specific components of the demersal fish community, such as plaice, cod and hake.
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NASA Astrophysics Data System (ADS)
Stige, Leif Chr.; Langangen, Øystein; Yaragina, Natalia A.; Vikebø, Frode B.; Bogstad, Bjarte; Ottersen, Geir; Stenseth, Nils Chr.; Hjermann, Dag Ø.
2015-05-01
Understanding the causes of the large interannual fluctuations in the recruitment to many marine fishes is a key challenge in fisheries ecology. We here propose that the combination of mechanistic and statistical modelling of the pelagic early life stages (ELS) prior to recruitment can be a powerful approach for improving our understanding of local-scale and population-scale dynamics. Specifically, this approach allows separating effects of ocean transport and survival, and thereby enhances the knowledge of the processes that regulate recruitment. We analyse data on the pelagic eggs, larvae and post-larvae of Northeast Arctic cod and on copepod nauplii, the main prey of the cod larvae. The data originate from two surveys, one in spring and one in summer, for 30 years. A coupled physical-biological model is used to simulate the transport, ambient temperature and development of cod ELS from spawning through spring and summer. The predictions from this model are used as input in a statistical analysis of the summer data, to investigate effects of covariates thought to be linked to growth and survival. We find significant associations between the local-scale ambient copepod nauplii concentration and temperature in spring and the local-scale occurrence of cod (post)larvae in summer, consistent with effects on survival. Moreover, years with low copepod nauplii concentrations and low temperature in spring are significantly associated with lower mean length of the cod (post)larvae in summer, likely caused in part by higher mortality leading to increased dominance of young and hence small individuals. Finally, we find that the recruitment at age 3 is strongly associated with the mean body length of the cod ELS, highlighting the biological significance of the findings.
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Stefansson, Gunnar; Rosenberg, Andrew A
2005-01-29
We consider combinations of three types of control measures for the management of fisheries when the input information for policy decisions is uncertain. The methods considered include effort controls, catch quotas and area closures. We simulated a hypothetical fishery loosely based on the Icelandic cod fishery, using a simple spatially explicit dynamic model. We compared the performance with respect to conserving the resource and economic return for each type of control measure alone and in combination. In general, combining more than one type of primary direct control on fishing provides a greater buffer to uncertainty than any single form of fishery control alone. Combining catch quota control with a large closed area is a most effective system for reducing the risk of stock collapse and maintaining both short and long-term economic performance. Effort controls can also be improved by adding closed areas to the management scheme. We recommend that multiple control methods be used wherever possible and that closed areas should be used to buffer uncertainty. To be effective, these closed areas must be large and exclude all principal gears to provide real protection from fishing mortality.
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Stefansson, Gunnar; Rosenberg, Andrew A.
2005-01-01
We consider combinations of three types of control measures for the management of fisheries when the input information for policy decisions is uncertain. The methods considered include effort controls, catch quotas and area closures. We simulated a hypothetical fishery loosely based on the Icelandic cod fishery, using a simple spatially explicit dynamic model. We compared the performance with respect to conserving the resource and economic return for each type of control measure alone and in combination. In general, combining more than one type of primary direct control on fishing provides a greater buffer to uncertainty than any single form of fishery control alone. Combining catch quota control with a large closed area is a most effective system for reducing the risk of stock collapse and maintaining both short and long-term economic performance. Effort controls can also be improved by adding closed areas to the management scheme. We recommend that multiple control methods be used wherever possible and that closed areas should be used to buffer uncertainty. To be effective, these closed areas must be large and exclude all principal gears to provide real protection from fishing mortality. PMID:15713593
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Molfese, Carlotta; Beare, Doug; Hall-Spencer, Jason M.
2014-01-01
The worldwide depletion of major fish stocks through intensive industrial fishing is thought to have profoundly altered the trophic structure of marine ecosystems. Here we assess changes in the trophic structure of the English Channel marine ecosystem using a 90-year time-series (1920–2010) of commercial fishery landings. Our analysis was based on estimates of the mean trophic level (mTL) of annual landings and the Fishing-in-Balance index (FiB). Food webs of the Channel ecosystem have been altered, as shown by a significant decline in the mTL of fishery landings whilst increases in the FiB index suggest increased fishing effort and fishery expansion. Large, high trophic level species (e.g. spurdog, cod, ling) have been increasingly replaced by smaller, low trophic level fish (e.g. small spotted catsharks) and invertebrates (e.g. scallops, crabs and lobster). Declining trophic levels in fisheries catches have occurred worldwide, with fish catches progressively being replaced by invertebrates. We argue that a network of fisheries closures would help rebalance the trophic status of the Channel and allow regeneration of marine ecosystems. PMID:25010196
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Federal Register 2010, 2011, 2012, 2013, 2014
2011-05-23
... gear to catcher vessels less than 60 feet (18.3 meters) length overall using hook-and-line or pot gear... catcher vessel apportionment to catcher vessels less than 60 feet length overall (LOA) using hook-and-line... feet LOA using hook-and-line or pot gear. Classification This action responds to the best available...
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Federal Register 2010, 2011, 2012, 2013, 2014
2012-12-05
... greater than or equal to 60 feet length overall (LOA) using pot gear to hook-and-line catcher/processors, pot catcher/processors, and catcher vessels less than 60 feet LOA using hook-and-line or pot gear in... total allowable catch (TAC) specified for catcher vessels greater than or equal to 60 feet length...
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50 CFR 622.208 - Minimum mesh size applicable to rock shrimp off Georgia and Florida.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 50 Wildlife and Fisheries 12 2013-10-01 2013-10-01 false Minimum mesh size applicable to rock... mesh size applicable to rock shrimp off Georgia and Florida. (a) The minimum mesh size for the cod end of a rock shrimp trawl net in the South Atlantic EEZ off Georgia and Florida is 17/8 inches (4.8 cm...
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50 CFR 622.208 - Minimum mesh size applicable to rock shrimp off Georgia and Florida.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 50 Wildlife and Fisheries 12 2014-10-01 2014-10-01 false Minimum mesh size applicable to rock... mesh size applicable to rock shrimp off Georgia and Florida. (a) The minimum mesh size for the cod end of a rock shrimp trawl net in the South Atlantic EEZ off Georgia and Florida is 17/8 inches (4.8 cm...
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Federal Register 2010, 2011, 2012, 2013, 2014
2012-11-13
... Vessels Using Jig Gear in the Central Regulatory Area of the Gulf of Alaska AGENCY: National Marine... vessels using jig gear in the Central Regulatory Area of the Gulf of Alaska (GOA). This action is... gear in the Central Regulatory Area of the GOA. DATES: Effective 1200 hrs, Alaska local time (A.l.t...
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Federal Register 2010, 2011, 2012, 2013, 2014
2013-01-22
.../Processors Using Trawl Gear in the Western Regulatory Area of the Gulf of Alaska AGENCY: National Marine... (C/Ps) using trawl gear in the Western Regulatory Area of the Gulf of Alaska (GOA). This action is... apportioned to C/Ps using trawl gear in the Western Regulatory Area of the GOA. DATES: Effective 1200 hours...
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Federal Register 2010, 2011, 2012, 2013, 2014
2013-02-13
... Vessels Using Pot Gear in the Central Regulatory Area of the Gulf of Alaska AGENCY: National Marine... gear in the Central Regulatory Area of the Gulf of Alaska (GOA). This action is necessary to prevent... pot gear in the Central Regulatory Area of the GOA. DATES: Effective 1200 hours, Alaska local time (A...
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Federal Register 2010, 2011, 2012, 2013, 2014
2013-02-01
... Vessels Using Pot Gear in the Western Regulatory Area of the Gulf of Alaska AGENCY: National Marine... using pot gear in the Western Regulatory Area of the Gulf of Alaska (GOA). This action is necessary to... vessels using pot gear in the Western Regulatory Area of the GOA. DATES: Effective 1200 hrs, Alaska local...
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Federal Register 2010, 2011, 2012, 2013, 2014
2013-04-23
... Catcher/Processors Using Hook-and-line Gear in the Western Regulatory Area of the Gulf of Alaska AGENCY.../processors (C/Ps) using hook-and-line gear in the Western Regulatory Area of the Gulf of Alaska (GOA). This... catch apportioned to C/Ps using hook-and-line gear in the Western Regulatory Area of the GOA. DATES...
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Federal Register 2010, 2011, 2012, 2013, 2014
2013-04-22
... Catcher/Processors Using Trawl Gear in the Central Regulatory Area of the Gulf of Alaska AGENCY: National... (C/Ps) using trawl gear in the Central Regulatory Area of the Gulf of Alaska (GOA). This action is... apportioned to C/Ps using trawl gear in the Central Regulatory Area of the GOA. DATES: Effective 1200 hours...
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Federal Register 2010, 2011, 2012, 2013, 2014
2012-02-17
.../Processors Using Trawl Gear in the Western Regulatory Area of the Gulf of Alaska AGENCY: National Marine... (C/Ps) using trawl gear in the Western Regulatory Area of the Gulf of Alaska (GOA). This action is... apportioned to C/Ps using trawl gear in the Western Regulatory Area of the GOA. DATES: Effective 1200 hrs...
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Federal Register 2010, 2011, 2012, 2013, 2014
2012-02-28
.../Processors Using Hook-and-Line Gear in the Central Regulatory Area of the Gulf of Alaska AGENCY: National... (C/Ps) using hook-and-line gear in the Central Regulatory Area of the Gulf of Alaska (GOA). This... catch apportioned to C/Ps using hook-and-line gear in the Central Regulatory Area of the GOA. DATES...
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Federal Register 2010, 2011, 2012, 2013, 2014
2012-10-30
... Vessels Using Pot Gear in the Central Regulatory Area of the Gulf of Alaska AGENCY: National Marine... vessels using pot gear in the Central Regulatory Area of the Gulf of Alaska (GOA). This action is... gear in the Central Regulatory Area of the GOA. DATES: Effective 1200 hrs, Alaska local time (A.l.t...
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Federal Register 2010, 2011, 2012, 2013, 2014
2013-09-05
... Catcher/Processors Using Trawl Gear in the Central Regulatory Area of the Gulf of Alaska AGENCY: National... (C/Ps) using trawl gear in the Central Regulatory Area of the Gulf of Alaska (GOA). This action is... gear in the Central Regulatory Area of the GOA. DATES: Effective 1200 hours, Alaska local time (A.l.t...
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ERIC Educational Resources Information Center
White, Melissa
2003-01-01
Introduces the problem of widespread worker displacement. Argues the problem is more severe in regions where the employment base centers on a single industry or resource. Considers two government programs developed to address the need resulting from closure of the Canadian northern cod fishery and decline of the mining industry in England. (CAJ)
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Federal Register 2010, 2011, 2012, 2013, 2014
2013-08-29
....S.C. 1801 et seq. Dated: August 26, 2013. Kelly Denit, Acting Deputy Director, Office of Sustainable... Islands Management Area (BSAI). This action is necessary to fully use the 2013 total allowable catch of.... DATES: Effective 1200 hrs, Alaska local time (A.l.t.), August 26, 2013, through 2400 hrs, A.l.t...
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50 CFR Table 1d to Part 660... - At-Sea Whiting Fishery Annual Set-Asides, 2011
Code of Federal Regulations, 2012 CFR
2012-10-01
... Set-Asides, 2011 Species of species complex Set-aside (mt) Lingcod 6 Pacific Cod 5 Pacific Whiting Allocation a Sablefish N. of 36° 50 Sablefish S. of 36° NA PACIFIC OCEAN PERCH Allocation a WIDOW ROCKFISH... California scorpionfish NA Cabezon (off CA only) NA Other Fish 520 Longnose Skate 5 Pacific Halibut 10 b a...
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Federal Register 2010, 2011, 2012, 2013, 2014
2011-03-03
...NMFS proposes regulations to implement measures in Framework Adjustment (FW) 45 to the NE Multispecies Fishery Management Plan (FMP). FW 45 was developed by the New England Fishery Management Council (Council) to prevent overfishing, rebuild overfished stocks, achieve optimum yield (OY), and minimize the economic impact of management measures on affected vessels, pursuant to the Magnuson- Stevens Fishery Conservation and Management Act (Magnuson-Stevens Act). This action would revise the biological reference points and stock status for pollock, update annual catch limits (ACLs) for several stocks for fishing years (FYs) 2011-2012, adjust the rebuilding program for Georges Bank (GB) yellowtail flounder, increase scallop vessel access to the Great South Channel Exemption Area, approve five new sectors, modify the existing dockside and at-sea monitoring requirements, revise several sector administrative provisions, establish a Gulf of Maine (GOM) Cod Spawning Protection Area, and refine measures affecting the catch of limited access NE multispecies Handgear A vessels. This action would disapprove the Council's proposed catch limits for GB yellowtail flounder for FY 2011, and instead propose new catch limits for this stock through emergency action authority based on new flexibility provided by the International Fisheries Agreement Clarification Act. This action is necessary to ensure that the fishery is managed on the basis of the best available science, to comply with the acceptable biological catch (ABC) control rules adopted in Amendment 16 to the FMP, and to enhance the viability of the fishery following the transition to sector management in 2010.
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Edvardsen, Rolf B; Malde, Ketil; Mittelholzer, Christian; Taranger, Geir Lasse; Nilsen, Frank
2011-03-01
The Atlantic cod, Gadus morhua, is an important species both for traditional fishery and increasingly also in fish farming. The Atlantic cod is also under potential threat from various environmental changes such as pollution and climate change, but the biological impact of such changes are not well known, in particular when it comes to sublethal effects that can be difficult to assert. Modern molecular and genomic approaches have revolutionized biological research during the last decade, and offer new avenues to study biological functions and e.g. the impact of anthropogenic activities at different life-stages for a given organism. In order to develop genomic data and genomic tools for Atlantic cod we conducted a program were we constructed 20 cDNA libraries, and produced and analyzed 44006 expressed sequence tags (ESTs) from these. Several tissues are represented in the multiple cDNA libraries, that differ in either sexual maturation or immulogical stimulation. This approach allowed us to identify genes that are expressed in particular tissues, life-stages or in response to specific stimuli, and also gives us information about potential functions of the transcripts. The ESTs were used to construct a 16k cDNA microarray to further investigate the cod transcriptome. Microarray analyses were preformed on pylorus, pituitary gland, spleen and testis of sexually maturing male cod. The four different tissues displayed tissue specific transcriptomes demonstrating that the cDNA array is working as expected and will prove to be a powerful tool in further experiments. Copyright © 2010 Elsevier Inc. All rights reserved.
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NASA Astrophysics Data System (ADS)
Drinkwater, Ken
2009-10-01
Concern about future anthropogenic warming has lead to demands for information on what might happen to fish and fisheries under various climate-change scenarios. One suggestion has been to use past events as a proxy for what will happen in the future. In this paper a comparison between the responses of Atlantic cod ( Gadus morhua) to two major warm periods in the North Atlantic during the 20th century is carried out to determine how reliable the past might be as a predictor of the future. The first warm period began during the 1920s, remained relatively warm through the 1960s, and was limited primarily to the northern regions (>60°N). The second warm period, which again covered the northern regions but also extended farther south (30°N), began in the 1990s and has continued into the present century. During the earlier warm period, the most northern of the cod stocks (West Greenland, Icelandic, and Northeast Arctic cod in the Barents Sea) increased in abundance, individual growth was high, recruitment was strong, and their distribution spread northward. Available plankton data suggest that these cod responses were driven by bottom-up processes. Fishing pressure increased during this period of high cod abundance and the northern cod stocks began to decline, as early as the 1950s in the Barents Sea but during the 1960s elsewhere. Individual growth declined as temperatures cooled and the cod distributions retracted southward. During the warming in the 1990s, the spawning stock biomass of cod in the Barents Sea again increased, recruitment rose, and the stock spread northward, but the individual growth did not improve significantly. Cod off West Greenland also have shown signs of improving recruitment and increasing biomass, albeit they are still very low in comparison to the earlier warming period. The abundance of Icelandic cod, on the other hand, has remained low through the recent warm period and spawning stock biomass and total biomass are at levels near the lowest on record. The different responses of cod to the two warm events, in particular the reduced cod production during the recent warm period, are attributed to the effects of intense fishing pressure and possibly related ecosystem changes. The implications of the results of the comparisons on the development of cod scenarios under future climate change are addressed.
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NASA Astrophysics Data System (ADS)
McCrackin, M. L.
2016-12-01
In order to better communicate relevant scientific knowledge to policy- and decision makers, Stockholm University and the Baltic Sea 2020 Foundation partnered to create Baltic Eye in 2014. Seven scientists and two communicators constitute the core team of this initiative. The team integrates communications with scientific analysis and synthesis of Baltic Sea environmental issues. In the past year, the team has focused on two main issues: fisheries management and microplastics. Baltic Sea cod stocks are in poor condition, with large numbers of small individuals. Baltic Eye recommended improvements to the European Union's multiannual fisheries plan to better align with ecosystem-based management principles: prioritization of cod stock recovery, greater consideration of natural variability of temperature and salinity (which affects cod spawning success), and inclusion of mechanisms to adjust quotas in the event of major environmental changes. Communications included policy briefs and debate articles targeted to the European Parliament, national government ministries, and non-governmental organizations. Every year, up to 40 tons of microplastics from personal care products are released in the Baltic Sea catchment. Baltic Eye raised awareness of the issue and made recommended ways to reduce microplastic emissions. Communications included a public presentation to journalists, politicians, and representatives of Swedish government ministries. A policy brief was provided Heads of Delegates of the Helsinki Commission (for protrection of the Baltic Sea environment) in advance of a meeting to develop a plan of action for marine litter. Researchers were interviewed for radio, TV, and print media in Sweden, Finland, and Germany. Next steps are to engage with multinational manufacturers about plans to voluntarily phase out microplastics in personal care products.
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NASA Astrophysics Data System (ADS)
McCrackin, M. L.
2016-02-01
In order to better communicate relevant scientific knowledge to policy- and decision makers, Stockholm University and the Baltic Sea 2020 Foundation partnered to create Baltic Eye in 2014. Seven scientists and two communicators constitute the core team of this initiative. The team integrates communications with scientific analysis and synthesis of Baltic Sea environmental issues. In the past year, the team has focused on two main issues: fisheries management and microplastics. Baltic Sea cod stocks are in poor condition, with large numbers of small individuals. Baltic Eye recommended improvements to the European Union's multiannual fisheries plan to better align with ecosystem-based management principles: prioritization of cod stock recovery, greater consideration of natural variability of temperature and salinity (which affects cod spawning success), and inclusion of mechanisms to adjust quotas in the event of major environmental changes. Communications included policy briefs and debate articles targeted to the European Parliament, national government ministries, and non-governmental organizations. Every year, up to 40 tons of microplastics from personal care products are released in the Baltic Sea catchment. Baltic Eye raised awareness of the issue and made recommended ways to reduce microplastic emissions. Communications included a public presentation to journalists, politicians, and representatives of Swedish government ministries. A policy brief was provided Heads of Delegates of the Helsinki Commission (for protrection of the Baltic Sea environment) in advance of a meeting to develop a plan of action for marine litter. Researchers were interviewed for radio, TV, and print media in Sweden, Finland, and Germany. Next steps are to engage with multinational manufacturers about plans to voluntarily phase out microplastics in personal care products.
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Preventing the collapse of the Baltic cod stock through an ecosystem-based management approach
Lindegren, Martin; Möllmann, Christian; Nielsen, Anders; Stenseth, Nils C.
2009-01-01
Worldwide a number of fish stocks have collapsed because of overfishing and climate-induced ecosystem changes. Developing ecosystem-based fisheries management (EBFM) to prevent these catastrophic events in the future requires ecological models incorporating both internal food-web dynamics and external drivers such as fishing and climate. Using a stochastic food-web model for a large marine ecosystem (i.e., the Baltic Sea) hosting a commercially important cod stock, we were able to reconstruct the history of the stock. Moreover we demonstrate that in hindsight the collapse could only have been avoidable by adapting fishing pressure to environmental conditions and food-web interactions. The modeling approach presented here represents a significant advance for EBFM, the application of which is important for sustainable resource management in the future. PMID:19706557
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Detoxification of olive mill wastewater by electrocoagulation and sedimentation processes.
Khoufi, Sonia; Feki, Firas; Sayadi, Sami
2007-04-02
Olive mill wastewater (OMW) is characterised by its high suspended solids content (SS), high turbidity (NTU), chemical oxygen demand (COD) concentration up to 100 gl(-1) and toxic phenolic compounds concentration up to 10 gl(-1). This study examined the effect of a physico-electrochemical method to detoxify olive mill wastewater prior an anaerobic biotreatment process. The proposed pre-treatment process consisted in a preliminary electrocoagulation step in which most phenolic compounds were polymerised, followed by a sedimentation step. The BOD(5)/COD ratio of the electrocoagulated OMW increased from 0.33, initial value, to 0.58. Furthermore, the sedimentation step yielded the removal of 76.2%, 75% and 71% of phenolic compounds, turbidity and suspended solid, respectively, after 3 days of plain settling. The combination of electrocoagulation and sedimentation allowed a COD reduction and decoloration of about 43% and 90%, respectively. This pre-treatment decreases the inhibition of Vibrio fisheri luminescence by 66.4%. Continuous anaerobic biomethanization experiments conducted in parallel with raw OMW and electrocoagulated OMW before and after sedimentation at a loading rate of 6g COD l(-1)day(-1), proved that the final pre-treated OMW was bioconverted into methane at high yield while raw OMW was very toxic to anaerobic microorganisms.
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A Novel Method for Predicting Anisakid Nematode Infection of Atlantic Cod Using Rough Set Theory.
Wąsikowska, Barbara; Sobecka, Ewa; Bielat, Iwona; Legierko, Monika; Więcaszek, Beata
2018-03-01
Atlantic cod ( Gadus morhua L.) is one of the most important fish species in the fisheries industries of many countries; however, these fish are often infected with parasites. The detection of pathogenic larval nematodes is usually performed in fish processing facilities by visual examination using candling or by digesting muscles in artificial digestive juices, but these methods are both time and labor intensive. This article presents an innovative approach to the analysis of cod parasites from both the Atlantic and Baltic Sea areas through the application of rough set theory, one of the methods of artificial intelligence, for the prediction of food safety in a food production chain. The parasitological examinations were performed focusing on nematode larvae pathogenic to humans, e.g., Anisakis simplex, Contracaecum osculatum, and Pseudoterranova decipiens. The analysis allowed identification of protocols with which it is possible to make preliminary estimates of the quantity and quality of parasites found in cod catches before detailed analyses are performed. The results indicate that the method used can be an effective analytical tool for these types of data. To achieve this goal, a database is needed that contains the patterns intensity of parasite infections and the conditions of commercial fish species in different localities in their distributions.
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Federal Register 2010, 2011, 2012, 2013, 2014
2013-05-03
...Through this interim final rule, NMFS announces that it partially approves Framework Adjustment 48 to the NE Multispecies Fishery Management Plan (FMP) and implements the approved measures in the regulations. Framework 48 is the first of two parallel and related actions developed by the New England Fishery Management Council (Council) to respond to updated stock status information and to adjust other management measures in the NE multispecies (groundfish) fishery beginning in fishing year (FY) 2013. This action implements new status determination criteria for Gulf of Maine (GOM) cod, Georges Bank (GB) cod, Southern New England/Mid-Atlantic (SNE/MA) yellowtail flounder, and white hake based on new benchmark assessments completed for these stocks in 2012 and 2013. NMFS is approving and implementing updated status determination criteria for white hake through this interim final rule and accepting further comment on this measure since it was not available for comment in the Framework 48 proposed rule. NMFS will publish a subsequent final rule to respond to any comments received, if necessary. Through this action, NMFS has also approved and is implementing the following Framework 48 measures: Elimination of dockside monitoring requirements for the groundfish fishery; lower minimum fish sizes for several groundfish stocks; clarified goals and performance standard for groundfish monitoring programs; revisions to the allocation of GB yellowtail flounder to the scallop fishery; and establishment of sub-annual catch limits (ACLs) of GB yellowtail flounder and SNE/MA windowpane flounder for the scallop and other non- groundfish fisheries. NMFS also approved revisions to recreational and commercial accountability measures (AMs), including amendments to existing AMs for windowpane flounder, ocean pout, and Atlantic halibut, and new ``reactive'' AMs for Atlantic wolffish and SNE/MA winter flounder, to address a remand by the U.S. District Court of Appeals. NMFS disapproved some measures in Framework 48: A provision for cost- sharing of monitoring costs between the industry and NMFS; a provision to delay industry-funded monitoring to FY 2014; finer scale discard rate strata for GB yellowtail flounder; and a provision to remove requirements for groundfish trawlers to stow their gear when transiting closed areas. Through this interim final rule, NMFS also withdraws a proposed correction to the regulations specific to monitoring of the Eastern U.S./Canada quotas, and will be accepting additional public comment on this issue. These measures are necessary to meet the requirements of the FMP and the Magnuson-Stevens Act, most notably preventing overfishing, ensuring that management measures are based on the best available science, and mitigating, to the extent practicable, potential negative economic impacts from reductions in catch limits anticipated for fishing year FY 2013.
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Federal Register 2010, 2011, 2012, 2013, 2014
2012-03-30
... under Executive Order 12866. Authority: 16 U.S.C. 1801 et seq. Dated: March 26, 2012. Emily H. Menashes... the keyword search. Locate the document you wish to comment on from the resulting list and click on... governing fishing by U.S. vessels in accordance with the FMP appear at subpart H of 50 CFR part 600 and 50...
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Federal Register 2010, 2011, 2012, 2013, 2014
2010-11-18
... Catcher Vessels Greater Than or Equal to 60 Feet (18.3 Meters) Length Overall Using Pot Gear in the Bering... to 60 feet (18.3 meters (m)) length overall (LOA) in the Bering Sea and Aleutian Islands management... (TAC) specified for pot catcher vessels greater than or equal to 60 feet (18.3 m) LOA in the BSAI...
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50 CFR Table 2d to Part 660... - At-Sea Whiting Fishery Annual Set-Asides, 2012 and beyond
Code of Federal Regulations, 2012 CFR
2012-10-01
... Annual Set-Asides, 2012 and beyond Species or species complex Set-aside (mt) Lingcod 6 Pacific Cod 5 Pacific Whiting Allocation a Sablefish N. of 36° 50 Sablefish S. of 36° NA PACIFIC OCEAN PERCH Allocation... Pacific Halibut 10 b a/ See Table 2.b., to Subpart C, for the at-sea whiting allocations for these species...
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Drira, Zaher; Kmiha-Megdiche, Salma; Sahnoun, Houda; Hammami, Ahmed; Allouche, Noureddine; Tedetti, Marc; Ayadi, Habib
2016-03-15
The coastal marine area of Sfax (Tunisia), which is well-known for its high productivity and fisheries, is also subjected to anthropogenic inputs from diverse industrial, urban and agriculture activities. We investigated the spatial distribution of physical, chemical and biogeochemical parameters in the surface waters of the southern coastal area of Sfax. Pertinent tracers of anthropogenic inputs were identified. Twenty stations were sampled during March 2013 in the vicinity of the coastal areas reserved for waste discharge. Phosphogypsum wastes dumped close to the beaches were the main source of PO4(3-), Cl(-) and SO4(2-) in seawater. The high content in total polyphenolic compounds was due to the olive oil treatment waste water released from margins. These inorganic and organic inputs in the surface waters were associated with elevated COD. The BOD5/COD (<0.5) and COD/BOD5 (>3) ratios highlighted a chemical pollution with organic load of a low biodegradability. Copyright © 2016 Elsevier Ltd. All rights reserved.
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A sampler for capturing larval and juvenile Atlantic menhaden
Hedrick, J.D.; Hedrick, L.R.; Margraf, F.J.
2005-01-01
Interest in capturing larval and juvenile Atlantic menhaden Brevoortia tyrannus for use in laboratory studies required the design and construction of a sampling device that would allow us to make collections of live fish from open-water areas. Our device for capturing 1-2.5-in larval-juvenile fish was constructed of a stainless steel frame that supported a 9.84-ft-long (3-m-long)5 cone plankton net with a 3.28-ft-diameter (1-m-diameter) opening and a 0.04-in (1-mm) mesh size. Although the plankton net was similar to that used during typical larval fish collections, the cod end was constructed of Plexiglas and was nearly watertight; this prevented impingement and injury to larval fish and provided a calm-water environment. The cod end was designed for quick release from the plankton net, and the entire cod end could be submerged into a 75-gal onboard holding tank. This design and technique obviated the netting or emerging of fish from the water until they were returned to the laboratory. ?? Copyright by the American Fisheries Society 2005.
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Daigle, Rémi M; Monaco, Cristián J; Elgin, Ashley K
2015-01-01
Around the world, governments are establishing Marine Protected Area (MPA) networks to meet their commitments to the United Nations Convention on Biological Diversity. MPAs are often used in an effort to conserve biodiversity and manage fisheries stocks. However, their efficacy and effect on fisheries yields remain unclear. We conducted a case-study on the economic impact of different MPA network design strategies on the Atlantic cod ( Gadus morhua ) fisheries in Canada. The open-source R package that we developed to analyze this case study can be customized to conduct similar analyses for other systems. We used a spatially-explicit individual-based model of population growth and dispersal coupled with a fisheries management and harvesting component. We found that MPA networks that both protect the target species' habitat and were spatially optimized to improve population connectivity had the highest net present value (i.e., were most profitable for the fishing industry). These higher profits were achieved primarily by reducing the distance travelled for fishing and reducing the probability of a moratorium event. These findings add to a growing body of knowledge demonstrating the importance of incorporating population connectivity in the MPA planning process, as well as the ability of this R package to explore ecological and economic consequences of alternative MPA network designs.
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NASA Astrophysics Data System (ADS)
Moffitt, Elizabeth A.; Punt, André E.; Holsman, Kirstin; Aydin, Kerim Y.; Ianelli, James N.; Ortiz, Ivonne
2016-12-01
Multi-species models can improve our understanding of the effects of fishing so that it is possible to make informed and transparent decisions regarding fishery impacts. Broad application of multi-species assessment models to support ecosystem-based fisheries management (EBFM) requires the development and testing of multi-species biological reference points (MBRPs) for use in harvest-control rules. We outline and contrast several possible MBRPs that range from those that can be readily used in current frameworks to those belonging to a broader EBFM context. We demonstrate each of the possible MBRPs using a simple two species model, motivated by walleye pollock (Gadus chalcogrammus) and Pacific cod (Gadus macrocephalus) in the eastern Bering Sea, to illustrate differences among methods. The MBRPs we outline each differ in how they approach the multiple, potentially conflicting management objectives and trade-offs of EBFM. These options for MBRPs allow multi-species models to be readily adapted for EBFM across a diversity of management mandates and approaches.
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Federal Register 2010, 2011, 2012, 2013, 2014
2012-02-14
... gear to catcher vessels less than 60 feet (18.3 meters) length overall using hook-and-line or pot gear... apportionment to catcher vessels less than 60 feet (18.3 meters(m)) length overall (LOA) using hook-and-line or... and 6,445 mt to catcher vessels less than 60 feet (18.3 m) LOA using hook-and-line or pot gear...
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Historical Arctic Logbooks Provide Insights into Past Diets and Climatic Responses of Cod
Townhill, Bryony L.; Maxwell, David; Engelhard, Georg H.; Simpson, Stephen D.; Pinnegar, John K.
2015-01-01
Gadus morhua (Atlantic cod) stocks in the Barents Sea are currently at levels not seen since the 1950s. Causes for the population increase last century, and understanding of whether such large numbers will be maintained in the future, are unclear. To explore this, we digitised and interrogated historical cod catch and diet datasets from the Barents Sea. Seventeen years of catch data and 12 years of prey data spanning 1930–1959 cover unexplored spatial and temporal ranges, and importantly capture the end of a previous warm period, when temperatures were similar to those currently being experienced. This study aimed to evaluate cod catch per unit effort and prey frequency in relation to spatial, temporal and environmental variables. There was substantial spatio-temporal heterogeneity in catches through the time series. The highest catches were generally in the 1930s and 1940s, although at some localities more cod were recorded late in the 1950s. Generalized Additive Models showed that environmental, spatial and temporal variables are all valuable descriptors of cod catches, with the highest occurring from 15–45°E longitude and 73–77°N latitude, at bottom temperatures between 2 and 4°C and at depths between 150 and 250 m. Cod diets were highly variable during the study period, with frequent changes in the relative frequencies of different prey species, particularly Mallotus villosus (capelin). Environmental variables were particularly good at describing the importance of capelin and Clupea harengus (herring) in the diet. These new analyses support existing knowledge about how the ecology of the region is controlled by climatic variability. When viewed in combination with more recent data, these historical relationships will be valuable in forecasting the future of Barents Sea fisheries, and in understanding how environments and ecosystems may respond. PMID:26331271
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Wilson, Robert E.; Sage, George K.; Sonsthagen, Sarah A.; Gravley, Megan C.; Menning, Damian; Talbot, Sandra L.
2017-01-01
The Arctic cod (Boreogadus saida) is an abundant marine fish that plays a vital role in the marine food web. To better understand the population genetic structure and the role of natural selection acting on the maternally-inherited mitochondrial genome (mitogenome), a molecule often associated with adaptations to temperature, we analyzed genetic data collected from 11 biparentally-inherited nuclear microsatellite DNA loci and nucleotide sequence data from from the mitochondrial DNA (mtDNA) cytochrome b (cytb) gene and, for a subset of individuals, the entire mitogenome. In addition, due to potential of species misidentification with morphologically similar Polar cod (Arctogadus glacialis), we used ddRAD-Seq data to determine the level of divergence between species and identify species-specific markers. Based on the findings presented here, Arctic cod across the Pacific Arctic (Bering, Chukchi, and Beaufort Seas) comprise a single panmictic population with high genetic diversity compared to other gadids. High genetic diversity was indicated across all 13 protein-coding genes in the mitogenome. In addition, we found moderate levels of genetic diversity in the nuclear microsatellite loci, with highest diversity found in the Chukchi Sea. Our analyses of markers from both marker classes (nuclear microsatellite fragment data and mtDNA cytb sequence data) failed to uncover a signal of microgeographic genetic structure within Arctic cod across the three regions, within the Alaskan Beaufort Sea, or between near-shore or offshore habitats. Further, data from a subset of mitogenomes revealed no genetic differentiation between Bering, Chukchi, and Beaufort seas populations for Arctic cod, Saffron cod (Eleginus gracilis), or Walleye pollock (Gadus chalcogrammus). However, we uncovered significant differences in the distribution of microsatellite alleles between the southern Chukchi and central and eastern Beaufort Sea samples of Arctic cod. Finally, using ddRAD-Seq data, we identified species-specific markers and in conjunction with mitogenome data, identified an Arctic cod x Polar cod hybrid in western Canadian Beaufort Sea. Overall, the lack of genetic structure among Arctic cod within the Bering, Chukchi and Beaufort seas of Alaska is concordant with the absence of geographic barriers to dispersal and typical among marine fishes. Arctic cod may exhibit a genetic pattern of isolation-by-distance, whereby populations in closer geographic proximity are more genetically similar than more distant populations. As this signal is only found between our two fartherest localities, data from populations elsewhere in the species’ global range are needed to determine if this is a general characteristic. Further, tests for selection suggested a limited role for natural selection acting on the mitochondrial genome of Arctic cod, but do not exclude the possibility of selection on genes involved in nuclear-mitogenome interactions. Unlike previous genetic assessment of Arctic cod sampled from the Chukchi Sea, the high levels of genetic diversity found in Arctic cod assayed in this study, across regions, suggests that the species in the Beaufort and Chukchi seas does not suffer from low levels of genetic variation, at least at neutral genetic markers. The large census size of Arctic cod may allow this species to retain high levels of genetic diversity. In addition, we discovered the presence of hybridization between Arctic and Polar cod (although low in frequency). Hybridization is expected to occur when environmental changes modify species distributions that result in contact between species that were previously separated. In such cases, hybridization may be an evolutionary mechanism that promotes an increase in genetic diversity that may provide species occupying changing environments with locally-adapted genotypes and, therefore, phenotypes. Natural selection can only act on the standing genetic variation present within a population. Therefore, given its higher levels of genetic diversity in combination with a large population size, Arctic cod may be resilient to current and future environmental change, as high genetic diversity is expected to increase opportunities for positive selection to act on genetic variants beneficial in different environments, regardless of the source of that genetic variation.
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Fishing Quotas, Induced Allee Effect, and Fluctuation-Driven Extinction.
Hastings, Harold M; Radin, Michael; Wiandt, Tamas
2017-01-01
We explore the potential of modifications to standard fishery models (for example Gordon-Schafer-Munro) to help understand events such as the collapse of the North Atlantic cod fishery. In particular we find that quota-driven and similar harvesting strategies induce an effective strong Allee effect (collapse if the population falls below a critical level). In the presence of environmental noise, fish population dynamics is similar to a random walk with (non-linear) drift. The expected survival time (first passage time to collapse) is shown to depend sensitively upon the amount of environmental noise and size of the 'safe zone' between the deterministic steady state population and the critical population level at which the system collapses; more precisely it is exponential in the cube of the size of the safe zone divided by the variance of the noise process. Similar scaling can be expected for more survival in more general systems with multiple steady states. Our calculations imply an amplification effect under which small increases in harvest yield large decreases in expected survival time, and one should be cautious in changes in harvesting, especially in fisheries with poor or limited data and fisheries affected by climate change.
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Estimating time-based instantaneous total mortality rate based on the age-structured abundance index
NASA Astrophysics Data System (ADS)
Wang, Yingbin; Jiao, Yan
2015-05-01
The instantaneous total mortality rate ( Z) of a fish population is one of the important parameters in fisheries stock assessment. The estimation of Z is crucial to fish population dynamics analysis, abundance and catch forecast, and fisheries management. A catch curve-based method for estimating time-based Z and its change trend from catch per unit effort (CPUE) data of multiple cohorts is developed. Unlike the traditional catch-curve method, the method developed here does not need the assumption of constant Z throughout the time, but the Z values in n continuous years are assumed constant, and then the Z values in different n continuous years are estimated using the age-based CPUE data within these years. The results of the simulation analyses show that the trends of the estimated time-based Z are consistent with the trends of the true Z, and the estimated rates of change from this approach are close to the true change rates (the relative differences between the change rates of the estimated Z and the true Z are smaller than 10%). Variations of both Z and recruitment can affect the estimates of Z value and the trend of Z. The most appropriate value of n can be different given the effects of different factors. Therefore, the appropriate value of n for different fisheries should be determined through a simulation analysis as we demonstrated in this study. Further analyses suggested that selectivity and age estimation are also two factors that can affect the estimated Z values if there is error in either of them, but the estimated change rates of Z are still close to the true change rates. We also applied this approach to the Atlantic cod ( Gadus morhua) fishery of eastern Newfoundland and Labrador from 1983 to 1997, and obtained reasonable estimates of time-based Z.
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Moland, Even; Olsen, Esben Moland; Knutsen, Halvor; Garrigou, Pauline; Espeland, Sigurd Heiberg; Kleiven, Alf Ring; André, Carl; Knutsen, Jan Atle
2013-01-01
Marine protected areas (MPAs) are increasingly implemented as tools to conserve and manage fisheries and target species. Because there are opportunity costs to conservation, there is a need for science-based assessment of MPAs. Here, we present one of the northernmost documentations of MPA effects to date, demonstrated by a replicated before–after control-impact (BACI) approach. In 2006, MPAs were implemented along the Norwegian Skagerrak coast offering complete protection to shellfish and partial protection to fish. By 2010, European lobster (Homarus gammarus) catch-per-unit-effort (CPUE) had increased by 245 per cent in MPAs, whereas CPUE in control areas had increased by 87 per cent. Mean size of lobsters increased by 13 per cent in MPAs, whereas increase in control areas was negligible. Furthermore, MPA-responses and population development in control areas varied significantly among regions. This illustrates the importance of a replicated BACI design for reaching robust conclusions and management decisions. Partial protection of Atlantic cod (Gadus morhua) was followed by an increase in population density and body size compared with control areas. By 2010, MPA cod were on average 5 cm longer than in any of the control areas. MPAs can be useful management tools in rebuilding and conserving portions of depleted lobster populations in northern temperate waters, and even for a mobile temperate fish species such as the Atlantic cod. PMID:23303544
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Morbidity and mortality in stranded Cook Inlet beluga whales Delphinapterus leucas.
Burek-Huntington, Kathleen A; Dushane, Jennifer L; Goertz, Caroline E C; Measures, Lena N; Romero, Carlos H; Raverty, Stephen A
2015-05-11
The endangered Cook Inlet (Alaska, USA) stock of beluga whales Delphinapterus leucas declined 47% between 1994 and 1998, from an estimated 653 whales to 347 whales, with a continued decline to approximately 312 in 2012. Between 1998 and 2013, 164 known dead strandings were reported by the National Marine Fisheries Service. Only 38 of these animals, or 23% of the known stranded carcasses, were necropsied. Carcasses were found between April and October. The majority of animals necropsied were adults (n=25), followed by juveniles (n=6), calves (n=3), and aborted fetuses (n=4). Eight of the 11 mature females were pregnant, post-partum, or lactating. Many (82%) of these belugas were in moderate to advanced autolysis, which hampered determination of a cause of death (COD). Each animal had a single primary COD assigned within a broad set of categories. The CODs were unknown (29%), trauma (18%), perinatal mortality (13%), mass stranding (13%), single stranding (11%), malnutrition (8%), or disease (8%). Other disease processes were coded as contributory or incidental to COD. Multiple animals had mild to moderate verminous pneumonia due to Stenurus arctomarinus, renal granulomas due to Crassicauda giliakiana, and ulcerative gastritis due to Anisakis sp. Each stranding affords a unique opportunity to obtain natural history data and evidence of human interactions, and, by long-term monitoring, to characterize pathologies of importance to individual and population health.
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von Dewitz, Burkhard; Tamm, Susanne; Höflich, Katharina; Voss, Rüdiger; Hinrichsen, Hans-Harald
2018-01-01
The semi-enclosed nature and estuarine characteristics, together with its strongly alternating bathymetry, make the Baltic Sea prone to much stronger interannual variations in the abiotic environment, than other spawning habitats of Atlantic cod (Gadus morhua). Processes determining salinity and oxygen conditions in the basins are influenced both by long term gradual climate change, e.g. global warming, but also by short-term meteorological variations and events. Specifically one main factor influencing cod spawning conditions, the advection of highly saline and well-oxygenated water masses from the North Sea, is observed in irregular frequencies and causes strong interannual variations in stock productivity. This study investigates the possibility to use the available hydrographic process knowledge to predict the annual spawning conditions for Eastern Baltic cod in its most important spawning ground, the Bornholm Basin, only by salinity measurements from a specific location in the western Baltic. Such a prediction could serve as an environmental early warning indicator to inform stock assessment and management. Here we used a hydrodynamic model to hindcast hydrographic property fields for the last 40+ years. High and significant correlations were found for months early in the year between the 33m salinity level in the Arkona Basin and the oxygen-dependent cod spawning environment in the Bornholm Basin. Direct prediction of the Eastern Baltic cod egg survival in the Bornholm Basin based on salinity values in the Arkona Basin at the 33 m depth level is shown to be possible for eggs spawned by mid-age and young females, which currently predominate the stock structure. We recommend to routinely perform short-term predictions of the Eastern Baltic cod spawning environment, in order to generate environmental information highly relevant for stock dynamics. Our statistical approach offers the opportunity to make best use of permanently existing infrastructure in the western Baltic to timely provide scientific knowledge on the spawning conditions of Eastern Baltic cod. Furthermore it could be a tool to assist ecosystem-based fisheries management with a cost-effective implementation by including the short term predictions as a simple indicator in the annual assessments.
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Tamm, Susanne; Höflich, Katharina; Voss, Rüdiger; Hinrichsen, Hans-Harald
2018-01-01
The semi-enclosed nature and estuarine characteristics, together with its strongly alternating bathymetry, make the Baltic Sea prone to much stronger interannual variations in the abiotic environment, than other spawning habitats of Atlantic cod (Gadus morhua). Processes determining salinity and oxygen conditions in the basins are influenced both by long term gradual climate change, e.g. global warming, but also by short-term meteorological variations and events. Specifically one main factor influencing cod spawning conditions, the advection of highly saline and well-oxygenated water masses from the North Sea, is observed in irregular frequencies and causes strong interannual variations in stock productivity. This study investigates the possibility to use the available hydrographic process knowledge to predict the annual spawning conditions for Eastern Baltic cod in its most important spawning ground, the Bornholm Basin, only by salinity measurements from a specific location in the western Baltic. Such a prediction could serve as an environmental early warning indicator to inform stock assessment and management. Here we used a hydrodynamic model to hindcast hydrographic property fields for the last 40+ years. High and significant correlations were found for months early in the year between the 33m salinity level in the Arkona Basin and the oxygen-dependent cod spawning environment in the Bornholm Basin. Direct prediction of the Eastern Baltic cod egg survival in the Bornholm Basin based on salinity values in the Arkona Basin at the 33 m depth level is shown to be possible for eggs spawned by mid-age and young females, which currently predominate the stock structure. We recommend to routinely perform short-term predictions of the Eastern Baltic cod spawning environment, in order to generate environmental information highly relevant for stock dynamics. Our statistical approach offers the opportunity to make best use of permanently existing infrastructure in the western Baltic to timely provide scientific knowledge on the spawning conditions of Eastern Baltic cod. Furthermore it could be a tool to assist ecosystem-based fisheries management with a cost-effective implementation by including the short term predictions as a simple indicator in the annual assessments. PMID:29768443
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Sexual size dimorphism in three North Sea gadoids.
Keyl, F; Kempf, A J; Sell, A F
2015-01-01
Existing biological data on whiting Merlangius merlangus, cod Gadus morhua and haddock Melanogrammus aeglefinus from a long-term international survey were analysed to address sexual size dimorphism (SSD) and its effect on their ecology and management. Results show that SSD, with larger females of the same age as males, is a result of higher growth rates in females. A direct consequence of SSD is the pronounced length-dependent female ratio that was found in all three gadoids in the North Sea. Female ratios of the three species changed from equality to female dominance at specific dominance transition lengths of c. 30, 35 and 60 cm for M. merlangus, G. morhua and M. aeglefinus, respectively. An analysis by area for M. merlangus also revealed length dependence of female ratios. SSD and length-dependent female ratios under most circumstances are inseparable. Higher overall energy demand as well as a higher energy uptake rate must result from the observed SSD and dimorphism in growth rates. Potential processes related to feeding, locomotion and physiology are proposed that could balance the increased energy investment of females. Potential consequences of SSD and length dependency of female ratios are the reduction of the reproductive potential of a stock due to size-selective fishing and biased assessment of the true size of the female spawning stock that could distort decisions in fisheries management. © 2014 The Fisheries Society of the British Isles.
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Economic repercussions of fisheries-induced evolution
Eikeset, Anne Maria; Richter, Andries; Dunlop, Erin S.; Dieckmann, Ulf; Stenseth, Nils Chr.
2013-01-01
Fish stocks experiencing high fishing mortality show a tendency to mature earlier and at a smaller size, which may have a genetic component and therefore long-lasting economic and biological effects. To date, the economic effects of such ecoevolutionary dynamics have not been empirically investigated. Using 70 y of data, we develop a bioeconomic model for Northeast Arctic cod to compare the economic yield in a model in which life-history traits can vary only through phenotypic plasticity with a model in which, in addition, genetic changes can occur. We find that evolutionary changes toward faster growth and earlier maturation occur consistently even if a stock is optimally managed. However, if a stock is managed optimally, the evolutionary changes actually increase economic yield because faster growth and earlier maturation raise the stock’s productivity. The optimal fishing mortality is almost identical for the evolutionary and nonevolutionary model and substantially lower than what it has been historically. Therefore, the costs of ignoring evolution under optimal management regimes are negligible. However, if fishing mortality is as high as it has been historically, evolutionary changes may result in economic losses, but only if the fishery is selecting for medium-sized individuals. Because evolution facilitates growth, the fish are younger and still immature when they are susceptible to getting caught, which outweighs the increase in productivity due to fish spawning at an earlier age. PMID:23836660
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NASA Astrophysics Data System (ADS)
Lilly, George R.; Nakken, Odd; Brattey, John
2013-07-01
Stocks of Atlantic cod (Gadus morhua) across the North Atlantic and adjacent seas have been fished intensively for years, and many are now severely depleted. In order to promote recovery and sustainable harvesting, it is essential to understand factors that have contributed to the declines and to variability in rates of recovery. Considerable insight may be gleaned by comparing and contrasting the histories of the Northeast Arctic (NEA) cod in the Barents Sea - Svalbard area of the northeast Atlantic and the “northern cod” on the Newfoundland and Labrador (NL) shelf in the northwest Atlantic. These two stocks, which were among the 3 largest cod stocks during the middle of the 20th century, are Arcto-boreal, and have many species of prey and predators in common. The biomass of NEA cod has varied considerably over time, and in 2009 was a little above 60% of its maximum observed level, which occurred in the late 1940s and early 1950s. In contrast, the biomass of NL cod decreased steadily from the early 1960s to the late 1970s, increased somewhat during the 1980s, and crashed during the early 1990s to an extremely low level, at which it remained for a decade before showing recent indications of improvement. Although both stocks were influenced by similar changes in harvesting strategies and environmental circumstances, both biotic and abiotic, there are two events which stand out as being particularly influential. First, crises developed in the management of both stocks in the late 1980s. For NEA cod, the crisis was environmental, caused by the collapse of capelin (Mallotus villosus), the main food for adult cod, whereas for NL cod the crisis was caused by a sudden large reduction in scientific perception of stock size. The difference in response to these crises strongly influenced subsequent stock dynamics. Catches of NEA cod were reduced considerably, preventing severe overharvesting of the cod that at that time experienced low productivity, whereas catches of NL cod were reduced only a little, contributing to escalating fishing mortality. The second event followed directly upon the first. The North Atlantic Oscillation index, which had been increasingly positive since the early 1970s, became strongly so during the early 1990s, creating favourable environmental conditions (warm water) in the Barents Sea and highly unfavourable conditions (cold water and extensive ice cover) on the Newfoundland-Labrador Shelf. The NEA stock recovered quickly, whereas the NL stock collapsed. The NEA cod has remained highly productive to this date, whereas the NL cod remained very unproductive for a decade, primarily because of high mortality, most of which appears to have been natural.
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Federal Register 2010, 2011, 2012, 2013, 2014
2010-03-12
... near future. For 2011, the model produces an ABC 15,000 mt higher than the proposed ABC. The SSC...,110,000 815,000 295,000 AI 19,000 19,000 0 19,000 19,000 0 Bogoslof 50 10 40 50 10 40 Pacific cod BSAI 168,780 193,030 -24,250 207,580 193,030 14,550 Sablefish BS 2,790 2,520 270 2,500 2,520 -20 AI 2,070 2...
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Burniol-Figols, Anna; Varrone, Cristiano; Le, Simone Balzer; Daugaard, Anders Egede; Skiadas, Ioannis V; Gavala, Hariklia N
2018-06-01
Crude glycerol is an important by-product of the biodiesel industry, which can be converted into volatile fatty acids (VFA) and/or 1,3-propanediol (1,3-PDO) by fermentation. In this study, a selective conversion of VFA to polyhydroxyalkanoates (PHA) was attained while leaving 1,3-PDO in the supernatant by means of mixed microbial consortia selection strategies. The process showed highly reproducible results in terms of PHA yield, 0.99 ± 0.07 C mol PHA/C mol S (0.84 g COD PHA/g COD S), PHA content (76 ± 3.1 g PHA/100 g TSS) and 1,3-PDO recovery (99 ± 2.1%). The combined process had an ultimate yield from crude glycerol of 0.19 g COD PHA and 0.42 g COD 1,3-PDO per g of input COD. The novel enrichment strategy applied for selectively transforming fermentation by-products into a high value product (PHA) demonstrates the significance of the enrichment process for targeting specific bio-transformations and could potentially prove valuable for other biotechnological applications as well. Copyright © 2018 Elsevier Ltd. All rights reserved.
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Chien, Yung-Ching; Masica, David L; Gray, Jeffrey J; Nguyen, Sarah; Vali, Hojatollah; McKee, Marc D
2009-08-28
Calcium oxalate dihydrate (COD) mineral and the urinary protein osteopontin/uropontin (OPN) are commonly found in kidney stones. To investigate the effects of OPN on COD growth, COD crystals were grown with phosphorylated OPN or a polyaspartic acid-rich peptide of OPN (DDLDDDDD, poly-Asp(86-93)). Crystals grown with OPN showed increased dimensions of the {110} prismatic faces attributable to selective inhibition at this crystallographic face. At high concentrations of OPN, elongated crystals with dominant {110} faces were produced, often with intergrown, interpenetrating twin crystals. Poly-Asp(86-93) dose-dependently elongated crystal morphology along the {110} faces in a manner similar to OPN. In crystal growth studies using fluorescently tagged poly-Asp(86-93) followed by imaging of crystal interiors using confocal microscopy, sectoral (compositional) zoning in COD was observed resulting from selective binding and incorporation (occlusion) of peptide exclusively into {110} crystal sectors. Computational modeling of poly-Asp(86-93) adsorption to COD {110} and {101} surfaces also suggests increased stabilization of the COD {110} surface and negligible change to the natively stable {101} surface. Ultrastructural, colloidal-gold immunolocalization of OPN by transmission electron microscopy in human stones confirmed an intracrystalline distribution of OPN. In summary, OPN and its poly-Asp(86-93) sequence similarly affect COD mineral growth; the {110} crystallographic faces become enhanced and dominant attributable to {110} face inhibition by the protein/peptide, and peptides can incorporate into the mineral phase. We, thus, conclude that the poly-Asp(86-93) domain is central to the OPN ability to interact with the {110} faces of COD, where it binds to inhibit crystal growth with subsequent intracrystalline incorporation (occlusion).
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Losing Track of Time: Is Hypoxia In Part To Blame For Baltic Cod Aging Problems?
NASA Astrophysics Data System (ADS)
Limburg, K. E.; Hussy, K.
2016-02-01
Cod, a primary fishery species in the Baltic Sea since prehistoric times, has recently experienced marked declines in size and condition. This is due to a combination of worsening water quality conditions from hypoxia intensification, reduction in prey availability even as cod densities have risen, and increased occurrence of parasites and disease. One of the net results of this has been a decrease in formation of clear annual growth rings in otoliths of Eastern Baltic Cod. Otoliths (ear-stones) are part of the hearing and balance system in fishes, and grow incrementally as a fish grows. In seasonal environments, growth bands are laid down, much like tree rings. But in Eastern Baltic cod it has become increasingly difficult to "read" otoliths and determine ages. This is a serious problem, because age is a key variable used in stock assessment for the management of exploited populations, including quota-setting. In 2014 the situation became so dire that the stock assessment was not approved for this stock. Solutions are clearly needed. We are developing new methods to assist in solving the "aging problem" using a combination of otolith microchemistry, optical imagery and direct increment counts, and dynamic models. Developing novel ratios of trace elements and isotopes that enhance seasonal signatures appears promising. We are also tracking the intensity of hypoxia with a proxy (Mn:Ca ratios) as described in Limburg et al. 2015 (J. Mar. Sys. 141: 167-178). This study explicitly links hypoxia with a metric (otolith Mn:Ca ratios) that also has a physiological basis; preliminary results suggest our approach to deal with aging fishes badly impacted by hypoxia is broadly applicable across marine to freshwater ecosystems.
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NASA Astrophysics Data System (ADS)
Arbianti, Rita; Surya Utami, Tania; Leondo, Vifki; Elisabeth; Andyah Putri, Syafira; Hermansyah, Heri
2018-03-01
Microbial Fuel Cell (MFC) provides a new alternative in the treatment of organic waste. MFC produces 50-90% less sludge to be disposed than other methods. MFC technology can utilize existing microorganisms in the waste as a catalyst to generate electricity and simultaneously also serves as a wastewater treatment unit itself. Tempeh wastewater is one of the abundant industrial wastewater which can be processed using MFC. Research using the selective mixed culture is very likely to do due to the good result on COD removals by adding mixed culture. Microorganisms in tempeh wastewater consist of bacteria gram positive and gram negative. This study focused on the aspects of waste treatment which is determined by decreased levels of COD and BOD. Variations in this study are the formation time of biofilm and the addition of selective gram. MFC operated for 50 hours. For a variation of biofilm formation, experiments were performed after incubation by replacing incubation substrates used in the formation of biofilms. Biofilm formation time in this study was 3 days, 5 days, 7 days and 14 days. Gram positive and gram negative bacteria were used in selective mixed culture experiments. Selective mixed culture added to the reactor by 1 mL and 5 mL. Selection of gram-positive or gram-negative bacteria carried by growing mixed culture on selective media. COD and BOD levels were measured in the wastewater before and after the experiment conducted in each variation. Biofilm formation optimum time is 7 days which decrease COD and BOD levels by 18.2% and 35.9%. The addition of gram negative bacteria decreases COD and BOD levels by 29.32% and 51.32%. Further research is needed in order to get a better result on decreasing levels of COD and BOD.
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Kuparinen, Anna; Stenseth, Nils Christian; Hutchings, Jeffrey A
2014-12-01
The evolution of life histories over contemporary time scales will almost certainly affect population demography. One important pathway for such eco-evolutionary interactions is the density-dependent regulation of population dynamics. Here, we investigate how fisheries-induced evolution (FIE) might alter density-dependent population-productivity relationships. To this end, we simulate the eco-evolutionary dynamics of an Atlantic cod (Gadus morhua) population under fishing, followed by a period of recovery in the absence of fishing. FIE is associated with increases in juvenile production, the ratio of juveniles to mature population biomass, and the ratio of the mature population biomass relative to the total population biomass. In contrast, net reproductive rate (R 0 ) and per capita population growth rate (r) decline concomitantly with evolution. Our findings suggest that FIE can substantially modify the fundamental population-productivity relationships that underlie density-dependent population regulation and that form the primary population-dynamical basis for fisheries stock-assessment projections. From a conservation and fisheries-rebuilding perspective, we find that FIE reduces R 0 and r, the two fundamental correlates of population recovery ability and inversely extinction probability.
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Dionisi, Davide; Majone, Mauro; Vallini, Giovanni; Gregorio, Simona Di; Beccari, Mario
2007-01-01
The effect of the length of the cycle on the enrichment and selection of mixed cultures in sequencing batch reactors (SBRs) has been studied, with the aim of biodegradable polymers (namely, polyhydroxyalkanoates (PHAs)) production from organic wastes. At a fixed feed concentration (20 gCOD/L) and organic loading rate (20 gCOD/L/day), the SBR was operated at different lengths of the cycle, in the range 1-8 h. Process performance was measured by considering the rates and yields of polymer storage and of the competing phenomenon of growth. The selected biomass was enriched with microorganisms that were able to store PHAs at high rates and yields only when the length of the cycle was 2 or 4 h, even though in these conditions the process was unstable. On the other hand, when the length of the cycle was 1 or 8 h, the dynamic response of the selected microorganisms was dominated by growth. The best process performance was characterized by storage rates in the range 500-600 mgCOD/gCOD/h and storage yields of 0.45-0.55 COD/COD. The corresponding productivity of the process was in the range 0.25-0.30 gPHA/L/h, the highest values obtained until now for mixed cultures. The microbial composition of the selected biomasses was analyzed through denaturing gradient gel electrophoresis (DGGE) and reverse-transcriptase denaturing gradient gel electrophoresis (RT-DGGE). The instability of the runs characterized by high storage rate was associated with a higher microbial heterogeneity compared to the runs with a stable growth response.
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Cyr, D G; Idler, D R; Audet, C; McLeese, J M; Eales, J G
1998-01-01
The recent collapse of the Northwestern Atlantic cod fisheries has coincided with a cooling of water temperatures. During this time the condition factor of cod has been poor. The objective of the present study was to determine the effects of long-term temperature acclimation on growth reproduction and thyroid function in laboratory held Atlantic cod (Gadus morhua). One of the key parameters used to assess thyroid function is the peripheral metabolism of L-thyroxine (T4) by microsomal deiodinase enzymes. Deiodinase function has not been described for gadid fish. T4 outer-ring deiodinating activity (apparent K(m) 1-2 nM) was confined primarily to liver. Its properties resembled those for hepatic T4ORD activity of other teleosts and the mammalian type II deiodinase. The T4ORD activity of cod liver exceeded that of salmonids and could explain the high plasma T3 levels (10-18 ng/ml), which were 2-5 times greater than T4 levels. T4 and T3 inner-ring deiodination was confined mainly to brain. In order to determine the effects of long-term temperature acclimation on cod, somatic growth, reproduction, and thyroidal status were assessed monthly in 400-900-g satiation-fed male Atlantic cod captured in June from the St. Lawrence Estuary and then acclimated from August to the following June under a natural photoperiod at 2-4 degrees C (LT) or 6-10 degrees C (HT). Reproductive status was determined from the gonadosomatic index (GSI), plasma testosterone (T) and 11-ketotestosterone (11-KT) levels, and the appearance of milt; thyroidal status was determined from plasma T4 and 3,5,3'-triiodo-L-thyronine (T3) levels and hepatic T4ORD activity to produce biologically active T3. Testis maturation (high levels of 1 and 11-KT, and milt release) occurred in April and May and was uninfluenced by acclimation temperature. LT cod grew more slowly than HT cod. Differences in body weight were particularly evident from December to February. In conclusion, (i) cod possess outer- and inner-ring deiodinase activities, predominating respectively in liver and brain, and with properties resembling those of other teleosts, (ii) T4ORD activity of liver is unusually high and may account for the high plasma T3 levels in this species, (iii) T4ORD activity tends to increase during periods of increased somatic growth, and (iv) chronic acclimation of male cod to 2-4 degrees C, as opposed to 6-10 degrees C, decreases somatic growth but does alter circulating levels of thyroid hormones and androgens and it does not change the time of sexual maturation.
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Adaptation to Low Salinity Promotes Genomic Divergence in Atlantic Cod (Gadus morhua L.)
Berg, Paul R.; Jentoft, Sissel; Star, Bastiaan; Ring, Kristoffer H.; Knutsen, Halvor; Lien, Sigbjørn; Jakobsen, Kjetill S.; André, Carl
2015-01-01
How genomic selection enables species to adapt to divergent environments is a fundamental question in ecology and evolution. We investigated the genomic signatures of local adaptation in Atlantic cod (Gadus morhua L.) along a natural salinity gradient, ranging from 35‰ in the North Sea to 7‰ within the Baltic Sea. By utilizing a 12 K SNPchip, we simultaneously assessed neutral and adaptive genetic divergence across the Atlantic cod genome. Combining outlier analyses with a landscape genomic approach, we identified a set of directionally selected loci that are strongly correlated with habitat differences in salinity, oxygen, and temperature. Our results show that discrete regions within the Atlantic cod genome are subject to directional selection and associated with adaptation to the local environmental conditions in the Baltic- and the North Sea, indicating divergence hitchhiking and the presence of genomic islands of divergence. We report a suite of outlier single nucleotide polymorphisms within or closely located to genes associated with osmoregulation, as well as genes known to play important roles in the hydration and development of oocytes. These genes are likely to have key functions within a general osmoregulatory framework and are important for the survival of eggs and larvae, contributing to the buildup of reproductive isolation between the low-salinity adapted Baltic cod and the adjacent cod populations. Hence, our data suggest that adaptive responses to the environmental conditions in the Baltic Sea may contribute to a strong and effective reproductive barrier, and that Baltic cod can be viewed as an example of ongoing speciation. PMID:25994933
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Grabowski, T.B.; Thorsteinsson, Vilhjalmur; McAdam, B.J.; Marteinsdottir, G.
2011-01-01
There is increasing recognition of intraspecific diversity and population structure within marine fish species, yet there is little direct evidence of the isolating mechanisms that maintain it or documentation of its ecological extent. We analyzed depth and temperature histories collected by electronic data storage tags retrieved from 104 Atlantic cod at liberty ???1 year to evaluate a possible isolating mechanisms maintaining population structure within the Icelandic cod stock. This stock consists of two distinct behavioral types, resident coastal cod and migratory frontal cod, each occurring within two geographically distinct populations. Despite being captured together on the same spawning grounds, we show the behavioral types seem reproductively isolated by fine-scale differences in spawning habitat selection, primarily depth. Additionally, the different groups occupied distinct seasonal thermal and bathymetric niches that generally demonstrated low levels of overlap throughout the year. Our results indicate that isolating mechanisms, such as differential habitat selection during spawning, might contribute to maintaining diversity and fine-scale population structure in broadcast-spawning marine fishes.
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Kuparinen, Anna; Kuikka, Sakari; Merilä, Juha
2009-05-01
The study of fisheries-induced evolution is a research field which is becoming recognized both as an important and interesting problem in applied evolution, as well as a practical management problem in fisheries. Much of the research in fisheries-induced evolution has focussed on quantifying and proving that an evolutionary response has taken place, but less effort has been invested on the actual processes and traits underlying capture of a fish by a fishing gear. This knowledge is not only needed to understand possible phenotypic selection associated to fishing but also to help to device sustainable fisheries and management strategies. Here, we draw attention to the existing knowledge about selectivity of fishing gears and outline the ways in which this information could be utilized in the context of fisheries-induced evolution. To these ends, we will introduce a mathematical framework commonly applied to quantify fishing gear selectivity, illustrate the link between gear selectivity and the change in the distribution of phenotypes induced by fishing, review what is known about selectivity of commonly used fishing gears, and discuss how this knowledge could be applied to improve attempts to predict evolutionary impacts of fishing.
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50 CFR Figure 1 to Part 660... - Diagram of Selective Flatfish Trawl
Code of Federal Regulations, 2014 CFR
2014-10-01
... 50 Wildlife and Fisheries 13 2014-10-01 2014-10-01 false Diagram of Selective Flatfish Trawl 1 Figure 1 to Part 660, Subpart D Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE (CONTINUED) FISHERIES OFF WEST COAST STATES...
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Berg, Paul R; Star, Bastiaan; Pampoulie, Christophe; Sodeland, Marte; Barth, Julia M I; Knutsen, Halvor; Jakobsen, Kjetill S; Jentoft, Sissel
2016-03-17
Identification of genome-wide patterns of divergence provides insight on how genomes are influenced by selection and can reveal the potential for local adaptation in spatially structured populations. In Atlantic cod - historically a major marine resource - Northeast-Arctic- and Norwegian coastal cod are recognized by fundamental differences in migratory and non-migratory behavior, respectively. However, the genomic architecture underlying such behavioral ecotypes is unclear. Here, we have analyzed more than 8.000 polymorphic SNPs distributed throughout all 23 linkage groups and show that loci putatively under selection are localized within three distinct genomic regions, each of several megabases long, covering approximately 4% of the Atlantic cod genome. These regions likely represent genomic inversions. The frequency of these distinct regions differ markedly between the ecotypes, spawning in the vicinity of each other, which contrasts with the low level of divergence in the rest of the genome. The observed patterns strongly suggest that these chromosomal rearrangements are instrumental in local adaptation and separation of Atlantic cod populations, leaving footprints of large genomic regions under selection. Our findings demonstrate the power of using genomic information in further understanding the population dynamics and defining management units in one of the world's most economically important marine resources.
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Bakke, Ingrid; Coward, Eivind; Andersen, Tom; Vadstein, Olav
2015-10-01
Marine fish larvae are immature upon hatching, and share their environment with high numbers of bacteria. The microbial communities associated with developing fish larvae might be structured by other factors than those important in developing terrestrial animals. Here, we analysed the beta (β)-diversity of the microbiota associated with developing cod larvae and compared it with the bacterial communities in water and live feed by applying pyrosequencing of bar coded v4 16S rDNA amplicons. A total of 15 phyla were observed in the cod larval microbiota. Proteobacteria was the most abundant, followed by Firmicutes, Bacteroidetes and Actinobacteria. The composition and diversity of the cod larval microbiota changed considerably with age. The temporal and spatial patterns of β-diversity could not be explained by stochastic processes, and did not coincide with changes in the rearing conditions. Furthermore, the larval microbiota was highly distinct from the water and the live feed microbiota, particularly at early developmental stages. However, the similarity between larval and water microbiota increased with age. This study suggests that strong selection in the host structures the cod larval microbiota. The changes in community structure observed with increasing age can be explained by altered selection pressure due to development of the intestinal system. © 2015 Society for Applied Microbiology and John Wiley & Sons Ltd.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Christiansen, J.S.; George, S.G.
The polar cod (Boreogadus saida) is recognized as a key species in Arctic marine food webs and it may, therefore, be important for the transfer of xenobiotics from lower trophic levels to its main predators, birds and sea mammals. The present work examines the effects of foods contaminated with 200 or 400 ppm crude oil on food selection patterns and appetite-growth relationship in polar cod using X-radiography. It is shown that sexually mature polar cod consumed mixtures of uncontaminated and oil-contaminated foods, and did not show a reduced overall appetite as compared with fish provided with uncontaminated food only. Foodmore » selection was, however, influenced by both sex and individual appetite. Male fish selected uncontaminated food when appetite was low, whereas females ingested contaminated and uncontaminated foods equally, irrespective of appetite level. The ingestion of oil-contaminated food led to a significant depression in growth performance in both male and female fish. Food contaminated with oil at a concentration of 500 ppm was completely rejected by both sexes. 6 refs., 4 figs., 2 tabs.« less
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Synergies between climate and management for Atlantic cod fisheries at high latitudes
Kjesbu, Olav Sigurd; Bogstad, Bjarte; Devine, Jennifer A.; Gjøsæter, Harald; Howell, Daniel; Ingvaldsen, Randi B.; Nash, Richard D. M.; Skjæraasen, Jon Egil
2014-01-01
The widespread depletion of commercially exploited marine living resources is often seen as a general failure of management and results in criticism of contemporary management procedures. When populations show dramatic and positive changes in population size, this invariably leads to questions about whether favorable climatic conditions or good management (or both) were responsible. The Barents Sea cod (Gadus morhua) stock has recently increased markedly and the spawning stock biomass is now at an unprecedented high. We identify the crucial social and environmental factors that made this unique growth possible. The relationship between vital rates of Barents Sea cod stock productivity (recruitment, growth, and mortality) and environment is investigated, followed by simulations of population size under different management scenarios. We show that the recent sustained reduction in fishing mortality, facilitated by the implementation of a “harvest control rule,” was essential to the increase in population size. Simulations show that a drastic reduction in fishing mortality has resulted in a doubling of the total population biomass compared with that expected under the former management regime. However, management alone was not solely responsible. We document that prevailing climate, operating through several mechanistic links, positively reinforced management actions. Heightened temperature resulted in an increase in the extent of the suitable feeding area for Barents Sea cod, likely offering a release from density-dependent effects (for example, food competition and cannibalism) through prolonged overlap with prey and improved adult stock productivity. Management and climate may thus interact to give a positive outlook for exploited high-latitude marine resources. PMID:24550465
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Synergies between climate and management for Atlantic cod fisheries at high latitudes.
Kjesbu, Olav Sigurd; Bogstad, Bjarte; Devine, Jennifer A; Gjøsæter, Harald; Howell, Daniel; Ingvaldsen, Randi B; Nash, Richard D M; Skjæraasen, Jon Egil
2014-03-04
The widespread depletion of commercially exploited marine living resources is often seen as a general failure of management and results in criticism of contemporary management procedures. When populations show dramatic and positive changes in population size, this invariably leads to questions about whether favorable climatic conditions or good management (or both) were responsible. The Barents Sea cod (Gadus morhua) stock has recently increased markedly and the spawning stock biomass is now at an unprecedented high. We identify the crucial social and environmental factors that made this unique growth possible. The relationship between vital rates of Barents Sea cod stock productivity (recruitment, growth, and mortality) and environment is investigated, followed by simulations of population size under different management scenarios. We show that the recent sustained reduction in fishing mortality, facilitated by the implementation of a "harvest control rule," was essential to the increase in population size. Simulations show that a drastic reduction in fishing mortality has resulted in a doubling of the total population biomass compared with that expected under the former management regime. However, management alone was not solely responsible. We document that prevailing climate, operating through several mechanistic links, positively reinforced management actions. Heightened temperature resulted in an increase in the extent of the suitable feeding area for Barents Sea cod, likely offering a release from density-dependent effects (for example, food competition and cannibalism) through prolonged overlap with prey and improved adult stock productivity. Management and climate may thus interact to give a positive outlook for exploited high-latitude marine resources.
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Ecosystem-based fisheries management requires a change to the selective fishing philosophy
Zhou, Shijie; Smith, Anthony D. M.; Punt, André E.; Richardson, Anthony J.; Gibbs, Mark; Fulton, Elizabeth A.; Pascoe, Sean; Bulman, Catherine; Bayliss, Peter; Sainsbury, Keith
2010-01-01
Globally, many fish species are overexploited, and many stocks have collapsed. This crisis, along with increasing concerns over flow-on effects on ecosystems, has caused a reevaluation of traditional fisheries management practices, and a new ecosystem-based fisheries management (EBFM) paradigm has emerged. As part of this approach, selective fishing is widely encouraged in the belief that nonselective fishing has many adverse impacts. In particular, incidental bycatch is seen as wasteful and a negative feature of fishing, and methods to reduce bycatch are implemented in many fisheries. However, recent advances in fishery science and ecology suggest that a selective approach may also result in undesirable impacts both to fisheries and marine ecosystems. Selective fishing applies one or more of the “6-S” selections: species, stock, size, sex, season, and space. However, selective fishing alters biodiversity, which in turn changes ecosystem functioning and may affect fisheries production, hindering rather than helping achieve the goals of EBFM. We argue here that a “balanced exploitation” approach might alleviate many of the ecological effects of fishing by avoiding intensive removal of particular components of the ecosystem, while still supporting sustainable fisheries. This concept may require reducing exploitation rates on certain target species or groups to protect vulnerable components of the ecosystem. Benefits to society could be maintained or even increased because a greater proportion of the entire suite of harvested species is used. PMID:20435916
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Ecosystem-based fisheries management requires a change to the selective fishing philosophy.
Zhou, Shijie; Smith, Anthony D M; Punt, André E; Richardson, Anthony J; Gibbs, Mark; Fulton, Elizabeth A; Pascoe, Sean; Bulman, Catherine; Bayliss, Peter; Sainsbury, Keith
2010-05-25
Globally, many fish species are overexploited, and many stocks have collapsed. This crisis, along with increasing concerns over flow-on effects on ecosystems, has caused a reevaluation of traditional fisheries management practices, and a new ecosystem-based fisheries management (EBFM) paradigm has emerged. As part of this approach, selective fishing is widely encouraged in the belief that nonselective fishing has many adverse impacts. In particular, incidental bycatch is seen as wasteful and a negative feature of fishing, and methods to reduce bycatch are implemented in many fisheries. However, recent advances in fishery science and ecology suggest that a selective approach may also result in undesirable impacts both to fisheries and marine ecosystems. Selective fishing applies one or more of the "6-S" selections: species, stock, size, sex, season, and space. However, selective fishing alters biodiversity, which in turn changes ecosystem functioning and may affect fisheries production, hindering rather than helping achieve the goals of EBFM. We argue here that a "balanced exploitation" approach might alleviate many of the ecological effects of fishing by avoiding intensive removal of particular components of the ecosystem, while still supporting sustainable fisheries. This concept may require reducing exploitation rates on certain target species or groups to protect vulnerable components of the ecosystem. Benefits to society could be maintained or even increased because a greater proportion of the entire suite of harvested species is used.
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Infant motivation in dental health: attitude without constant reinforcement.
Teixeira Alves, Fabiana Bucholdz; Kuhn, Eunice; Bordin, Danielle; Kozlowski, Vitoldo Antonio; Raggio, Daniela Procida; Fadel, Cristina Berger
2014-01-01
Social factors determine the child's behavior and motivation is an important task in the teaching-learning process. This longitudinal and cross-sectional study aimed to analyze the effectiveness of a motivational activity program for oral hygiene habits formation after motivation and without constant reinforcement. The sample was constituted of 26 children (mean 6 years old) from a Public Kindergarten School in Ponta Grossa, PR, Brazil. Data were collected applying a test-chart, with figures reporting the process of dental health/illness. Some figures were considered positive to dental health (dentist/Cod 1, toothbrush/Cod 3, dentifrice/dental floss/Cod 6, fruits/vegetables/Cod 7 and tooth without caries lesion/Cod 8) and negative on dental health (sweets/Cod 2, bacteria/Cod 4, tooth with caries lesion/Cod 5). The figures presentation occurred in three different stages: First stage - figures were presented to children without previous knowledge; second stage - following the motivational presentation, and third stage - 30 days after the first contact. On the first stage, most children select good for the figures considered harmful to their teeth (Cod 2-88%; Cod 4-77% and Cod 5-65%). On the second stage, there was a lower percentage: 23% (P < 0.0001), 8% (P < 0.0001), and 23% (P = 0.0068) related to the Cod 2, 4, and 5. On the third stage, the results showed again an association with the good choice to these figures considered harmful (Cod 2-85%, Cod 4-65% and Cod 5-54%) similar the results obtained on the first stage. The motivational programs performed without constant reinforcement does not have a positive influence in changing the child's behavior related to a better dental care.
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Ocean Acidification Effects on Atlantic Cod Larval Survival and Recruitment to the Fished Population
Stiasny, Martina H.; Mittermayer, Felix H.; Sswat, Michael; Voss, Rüdiger; Jutfelt, Fredrik; Chierici, Melissa; Puvanendran, Velmurugu; Mortensen, Atle; Reusch, Thorsten B. H.; Clemmesen, Catriona
2016-01-01
How fisheries will be impacted by climate change is far from understood. While some fish populations may be able to escape global warming via range shifts, they cannot escape ocean acidification (OA), an inevitable consequence of the dissolution of anthropogenic carbon dioxide (CO2) emissions in marine waters. How ocean acidification affects population dynamics of commercially important fish species is critical for adapting management practices of exploited fish populations. Ocean acidification has been shown to impair fish larvae’s sensory abilities, affect the morphology of otoliths, cause tissue damage and cause behavioural changes. Here, we obtain first experimental mortality estimates for Atlantic cod larvae under OA and incorporate these effects into recruitment models. End-of-century levels of ocean acidification (~1100 μatm according to the IPCC RCP 8.5) resulted in a doubling of daily mortality rates compared to present-day CO2 concentrations during the first 25 days post hatching (dph), a critical phase for population recruitment. These results were consistent under different feeding regimes, stocking densities and in two cod populations (Western Baltic and Barents Sea stock). When mortality data were included into Ricker-type stock-recruitment models, recruitment was reduced to an average of 8 and 24% of current recruitment for the two populations, respectively. Our results highlight the importance of including vulnerable early life stages when addressing effects of climate change on fish stocks. PMID:27551924
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Stiasny, Martina H; Mittermayer, Felix H; Sswat, Michael; Voss, Rüdiger; Jutfelt, Fredrik; Chierici, Melissa; Puvanendran, Velmurugu; Mortensen, Atle; Reusch, Thorsten B H; Clemmesen, Catriona
2016-01-01
How fisheries will be impacted by climate change is far from understood. While some fish populations may be able to escape global warming via range shifts, they cannot escape ocean acidification (OA), an inevitable consequence of the dissolution of anthropogenic carbon dioxide (CO2) emissions in marine waters. How ocean acidification affects population dynamics of commercially important fish species is critical for adapting management practices of exploited fish populations. Ocean acidification has been shown to impair fish larvae's sensory abilities, affect the morphology of otoliths, cause tissue damage and cause behavioural changes. Here, we obtain first experimental mortality estimates for Atlantic cod larvae under OA and incorporate these effects into recruitment models. End-of-century levels of ocean acidification (~1100 μatm according to the IPCC RCP 8.5) resulted in a doubling of daily mortality rates compared to present-day CO2 concentrations during the first 25 days post hatching (dph), a critical phase for population recruitment. These results were consistent under different feeding regimes, stocking densities and in two cod populations (Western Baltic and Barents Sea stock). When mortality data were included into Ricker-type stock-recruitment models, recruitment was reduced to an average of 8 and 24% of current recruitment for the two populations, respectively. Our results highlight the importance of including vulnerable early life stages when addressing effects of climate change on fish stocks.
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Winery wastewater treatment by combination of Cryptococcus laurentii and Fenton's reagent.
Santos, Cátia; Lucas, Marco S; Dias, Albino A; Bezerra, Rui M F; Peres, José A; Sampaio, Ana
2014-12-01
Winery wastewaters (WW) have high levels of organic matter, resulting in high COD and BOD and suspended solids. This paper studies the combination of biological and chemical processes in WW treatment. Among 10 yeast isolates, Filobasidium sp. (AGG 577) and Cryptococcus laurentii (AGG 726) were selected due to their superior performance in COD removal. During WW degradation, COD and total polyphenols (TPP) content removal of 89-90% for Filobasidium sp. and 90-93% for C. laurentii were obtained. However, despite similar degradation efficiency for both yeasts, COD kinetics and pH evolution during treatment reveals that C. laurentii presents a faster response than Filobasidium sp. The toxicity (inhibition of Vibrio fischeri luminescence) of C. laurentii treated WW decreases to an inhibition value below 2.5%. However, treated WW exceeds the legal limits, making necessary an additional treatment. In this case, the selection of Fenton's reagent as a chemical final polish step process is a good compromise between efficiency and lower practical complexity. The best results for both COD and TPP removal were obtained with H2O2 initial concentration of 39.2mM and a H2O2:Fe(2+) molar ratio of 15:1. The combined C. laurentii - Fenton's reagent treatment of WW achieved a total reduction of 98% and 96%, for COD and TPP, respectively. Copyright © 2014 Elsevier Ltd. All rights reserved.
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Recruitment Variability in North Atlantic Cod and Match-Mismatch Dynamics
Kristiansen, Trond; Drinkwater, Kenneth F.; Lough, R. Gregory; Sundby, Svein
2011-01-01
Background Fisheries exploitation, habitat destruction, and climate are important drivers of variability in recruitment success. Understanding variability in recruitment can reveal mechanisms behind widespread decline in the abundance of key species in marine and terrestrial ecosystems. For fish populations, the match-mismatch theory hypothesizes that successful recruitment is a function of the timing and duration of larval fish abundance and prey availability. However, the underlying mechanisms of match-mismatch dynamics and the factors driving spatial differences between high and low recruitment remain poorly understood. Methodology/Principal Findings We used empirical observations of larval fish abundance, a mechanistic individual-based model, and a reanalysis of ocean temperature data from 1960 to 2002 to estimate the survival of larval cod (Gadus morhua). From the model, we quantified how survival rates changed during the warmest and coldest years at four important cod spawning sites in the North Atlantic. The modeled difference in survival probability was not large for any given month between cold or warm years. However, the cumulative effect of higher growth rates and survival through the entire spawning season in warm years was substantial with 308%, 385%, 154%, and 175% increases in survival for Georges Bank, Iceland, North Sea, and Lofoten cod stocks, respectively. We also found that the importance of match-mismatch dynamics generally increased with latitude. Conclusions/Significance Our analyses indicate that a key factor for enhancing survival is the duration of the overlap between larval and prey abundance and not the actual timing of the peak abundance. During warm years, the duration of the overlap between larval fish and their prey is prolonged due to an early onset of the spring bloom. This prolonged season enhances cumulative growth and survival, leading to a greater number of large individuals with enhanced potential for survival to recruitment. PMID:21408215
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50 CFR 222.403 - Duration of selection; effective date.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 50 Wildlife and Fisheries 9 2011-10-01 2011-10-01 false Duration of selection; effective date. 222.403 Section 222.403 Wildlife and Fisheries NATIONAL MARINE FISHERIES SERVICE, NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE MARINE MAMMALS GENERAL ENDANGERED AND THREATENED MARINE...
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50 CFR 222.403 - Duration of selection; effective date.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 50 Wildlife and Fisheries 10 2012-10-01 2012-10-01 false Duration of selection; effective date. 222.403 Section 222.403 Wildlife and Fisheries NATIONAL MARINE FISHERIES SERVICE, NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE MARINE MAMMALS GENERAL ENDANGERED AND THREATENED MARINE...
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Petersen, Maria Faldborg; Steffensen, John Fleng
2003-01-01
Atlantic cod Gadus morhua has polymorphic haemoglobin, which can be separated into two homozygous types, HbI-1 and HbI-2, and one heterozygous type HbI-1/2. The geographical distribution of Atlantic cod with the different haemoglobin types varies, with the HbI(2) allele occurring at high frequency in northern regions, and the HbI(1) allele dominant in warmer areas. To determine if temperature is a selective parameter in the distribution of the haemoglobin types, the preferred temperature of the homozygous genotypes HbI-1 and HbI-2 was measured. We found that HbI-2 cod preferred a temperature of 8.2+/-1.5 degrees C while HbI-1 cod preferred 15.4+/-1.1 degrees C, and this preference was significant. The effect of hypoxia (35% oxygen saturation) on the preferred temperature was also measured. Previous studies showed that the preferred temperature of fish decreases during hypoxia, and this was the case for HbI-1 cod, which preferred 9.8+/-1.8 degrees C during hypoxia, whereas HbI-2 cod did not show this effect. The results indicate that environmental temperature changes will lead to a distributional change in the different haemoglobin types of Atlantic cod, global warming providing an advantage for HbI-1 cod. However, since HbI-1 cod prefer a low temperature under hypoxic conditions, a combination of increased water temperature and hypoxia could be unfavourable for Atlantic cod stocks.
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Prediction of biodegradability of aromatics in water using QSAR modeling.
Cvetnic, Matija; Juretic Perisic, Daria; Kovacic, Marin; Kusic, Hrvoje; Dermadi, Jasna; Horvat, Sanja; Bolanca, Tomislav; Marin, Vedrana; Karamanis, Panaghiotis; Loncaric Bozic, Ana
2017-05-01
The study was aimed at developing models for predicting the biodegradability of aromatic water pollutants. For that purpose, 36 single-benzene ring compounds, with different type, number and position of substituents, were used. The biodegradability was estimated according to the ratio of the biochemical (BOD 5 ) and chemical (COD) oxygen demand values determined for parent compounds ((BOD 5 /COD) 0 ), as well as for their reaction mixtures in half-life achieved by UV-C/H 2 O 2 process ((BOD 5 /COD) t1/2 ). The models correlating biodegradability and molecular structure characteristics of studied pollutants were derived using quantitative structure-activity relationship (QSAR) principles and tools. Upon derivation of the models and calibration on the training and subsequent testing on the test set, 3- and 5-variable models were selected as the most predictive for (BOD 5 /COD) 0 and (BOD 5 /COD) t1/2 , respectively, according to the values of statistical parameters R 2 and Q 2 . Hence, 3-variable model predicting (BOD 5 /COD) 0 possessed R 2 =0.863 and Q 2 =0.799 for training set, and R 2 =0.710 for test set, while 5-variable model predicting (BOD 5 /COD) 1/2 possessed R 2 =0.886 and Q 2 =0.788 for training set, and R 2 =0.564 for test set. The selected models are interpretable and transparent, reflecting key structural features that influence targeted biodegradability and can be correlated with the degradation mechanisms of studied compounds by UV-C/H 2 O 2 . Copyright © 2017 Elsevier Inc. All rights reserved.
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The U.S. Environmental Protection Agency (EPA) is seeking public comment on the EPA’s proposal indicating no further action is needed for multiple Training Areas on the Camp Edwards portion of Joint Base Cape Cod (JBCC).
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50 CFR Figure 1 to Subpart G of... - Diagram of Selective Flatfish Trawl
Code of Federal Regulations, 2010 CFR
2010-10-01
... Figure 1 to Subpart G of Part 660 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL.... § 660.360 Recreational fishery-management measures. (a) General. Federal recreational groundfish... recreational “other flatfish” fishery). (c) State-specific recreational fishery management measures. Federal...
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Akimova, Anna; Núñez-Riboni, Ismael; Kempf, Alexander; Taylor, Marc H.
2016-01-01
Understanding of the processes affecting recruitment of commercially important fish species is one of the major challenges in fisheries science. Towards this aim, we investigated the relation between North Sea hydrography (temperature and salinity) and fish stock variables (recruitment, spawning stock biomass and pre-recruitment survival index) for 9 commercially important fishes using spatially-resolved cross-correlation analysis. We used high-resolution (0.2° × 0.2°) hydrographic data fields matching the maximal temporal extent of the fish population assessments (1948–2013). Our approach allowed for the identification of regions in the North Sea where environmental variables seem to be more influential on the fish stocks, as well as the regions of a lesser or nil influence. Our results confirmed previously demonstrated negative correlations between temperature and recruitment of cod and plaice and identified regions of the strongest correlations (German Bight for plaice and north-western North Sea for cod). We also revealed a positive correlation between herring spawning stock biomass and temperature in the Orkney-Shetland area, as well as a negative correlation between sole pre-recruitment survival index and temperature in the German Bight. A strong positive correlation between sprat stock variables and salinity in the central North Sea was also found. To our knowledge the results concerning correlations between North Sea hydrography and stocks’ dynamics of herring, sole and sprat are novel. The new information about spatial distribution of the correlation provides an additional help to identify mechanisms underlying these correlations. As an illustration of the utility of these results for fishery management, an example is provided that incorporates the identified environmental covariates in stock-recruitment models. PMID:27584155
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Cemento-Osseous Dysplasias: Imaging Features Based on Cone Beam Computed Tomography Scans.
Cavalcanti, Paulo Henrique Pereira; Nascimento, Eduarda Helena Leandro; Pontual, Maria Luiza Dos Anjos; Pontual, Andréa Dos Anjos; Marcelos, Priscylla Gonçalves Correia Leite de; Perez, Danyel Elias da Cruz; Ramos-Perez, Flávia Maria de Moraes
2018-01-01
Imaging exams have important role in diagnosis of cemento-osseous dysplasia (COD). Cone beam computed tomography (CBCT) stands out for allowing three-dimensional image evaluation. This study aimed to assess the prevalence of cases diagnosed as COD on CBCT scans, as well identify the main imaging features related to these lesions. An analysis was performed in a database containing 22,400 radiological reports, in which all cases showing some type of COD were initially selected. These CBCT exams were reevaluated to confirm the radiographic diagnosis and determine the prevalence and distribution of the types of COD with regard to gender, age and preferred location, while describing its most common imaging aspects. Data were presented using descriptive analyses. There were 82 cases diagnosed as COD in the CBCT images (prevalence of 0.4%). The distribution of patients was 11 (13.4%) male and 71 (86.6%) female, with a mean age of 49.8 years (age-range 17-85 years). There were 47 (57.3%) cases of periapical COD, 23 (28%) of focal COD and 12 (14.6%) of florid COD. The mandible was more affected than the maxilla. In most cases, the lesions were mixed or hyperdense. All COD had well-defined limits and there were no cases of tooth displacement. In conclusion, periapical COD was the most common type and the most affected bone was the mandible. Imaging evaluation is critical for diagnosis and dentists should bear in mind all possible radiographic presentations of COD in order to prevent misleading diagnoses and consequently, inadequate treatments.
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Lewis-Alleyne, Lesley C; Bassil, Bassem S; Böttcher, Tobias; Röschenthaler, Gerd-Volker
2014-11-14
NHC(Me)SiCl4 (NHC(Me) = 1,3-dimethylimidazolidin-2-ylidene) was used to synthesise novel NHC(Me)-Pt(ii) complexes. An atypical trans-cis isomerisation process was also achieved for [(NHC(Me))2PtCl2], while the synthesis of the unique double-complex salt [(NHC(Me))Pt(cod)Cl] [(NHC(Me))PtCl3] (cod = 1,5-cyclooctadiene) revealed the first-ever N-heterocyclic carbene analogue of the Cossa's salt anion.
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On Selective Harvesting of an Inshore-Offshore Fishery: A Bioeconomic Model
ERIC Educational Resources Information Center
Purohit, D.; Chaudhuri, K. S.
2004-01-01
A bioeconomic model is developed for the selective harvesting of a single species, inshore-offshore fishery, assuming that the growth of the species is governed by the Gompertz law. The dynamical system governing the fishery is studied in depth; the local and global stability of its non-trivial steady state are examined. Existence of a bionomic…
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Ancient DNA reveals the Arctic origin of Viking Age cod from Haithabu, Germany
Star, Bastiaan; Boessenkool, Sanne; Gondek, Agata T.; Nikulina, Elena A.; Hufthammer, Anne Karin; Pampoulie, Christophe; Knutsen, Halvor; André, Carl; Nistelberger, Heidi M.; Dierking, Jan; Petereit, Christoph; Heinrich, Dirk; Jakobsen, Kjetill S.; Stenseth, Nils Chr.; Jentoft, Sissel
2017-01-01
Knowledge of the range and chronology of historic trade and long-distance transport of natural resources is essential for determining the impacts of past human activities on marine environments. However, the specific biological sources of imported fauna are often difficult to identify, in particular if species have a wide spatial distribution and lack clear osteological or isotopic differentiation between populations. Here, we report that ancient fish-bone remains, despite being porous, brittle, and light, provide an excellent source of endogenous DNA (15–46%) of sufficient quality for whole-genome reconstruction. By comparing ancient sequence data to that of modern specimens, we determine the biological origin of 15 Viking Age (800–1066 CE) and subsequent medieval (1066–1280 CE) Atlantic cod (Gadus morhua) specimens from excavation sites in Germany, Norway, and the United Kingdom. Archaeological context indicates that one of these sites was a fishing settlement for the procurement of local catches, whereas the other localities were centers of trade. Fish from the trade sites show a mixed ancestry and are statistically differentiated from local fish populations. Moreover, Viking Age samples from Haithabu, Germany, are traced back to the North East Arctic Atlantic cod population that has supported the Lofoten fisheries of Norway for centuries. Our results resolve a long-standing controversial hypothesis and indicate that the marine resources of the North Atlantic Ocean were used to sustain an international demand for protein as far back as the Viking Age. PMID:28784790
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Ancient DNA reveals the Arctic origin of Viking Age cod from Haithabu, Germany.
Star, Bastiaan; Boessenkool, Sanne; Gondek, Agata T; Nikulina, Elena A; Hufthammer, Anne Karin; Pampoulie, Christophe; Knutsen, Halvor; André, Carl; Nistelberger, Heidi M; Dierking, Jan; Petereit, Christoph; Heinrich, Dirk; Jakobsen, Kjetill S; Stenseth, Nils Chr; Jentoft, Sissel; Barrett, James H
2017-08-22
Knowledge of the range and chronology of historic trade and long-distance transport of natural resources is essential for determining the impacts of past human activities on marine environments. However, the specific biological sources of imported fauna are often difficult to identify, in particular if species have a wide spatial distribution and lack clear osteological or isotopic differentiation between populations. Here, we report that ancient fish-bone remains, despite being porous, brittle, and light, provide an excellent source of endogenous DNA (15-46%) of sufficient quality for whole-genome reconstruction. By comparing ancient sequence data to that of modern specimens, we determine the biological origin of 15 Viking Age (800-1066 CE) and subsequent medieval (1066-1280 CE) Atlantic cod ( Gadus morhua ) specimens from excavation sites in Germany, Norway, and the United Kingdom. Archaeological context indicates that one of these sites was a fishing settlement for the procurement of local catches, whereas the other localities were centers of trade. Fish from the trade sites show a mixed ancestry and are statistically differentiated from local fish populations. Moreover, Viking Age samples from Haithabu, Germany, are traced back to the North East Arctic Atlantic cod population that has supported the Lofoten fisheries of Norway for centuries. Our results resolve a long-standing controversial hypothesis and indicate that the marine resources of the North Atlantic Ocean were used to sustain an international demand for protein as far back as the Viking Age.
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Quantifying six decades of fishery selection for size and age at maturity in sockeye salmon
Kendall, Neala W; Hard, Jeffrey J; Quinn, Thomas P
2009-01-01
Life history traits of wild animals can be strongly influenced, both phenotypically and evolutionarily, by hunting and fishing. However, few studies have quantified fishery selection over long time periods. We used 57 years of catch and escapement data to document the magnitude of and trends in gillnet selection on age and size at maturity of a commercially and biologically important sockeye salmon stock. Overall, the fishery has caught larger fish than have escaped to spawn, but selection has varied over time, becoming weaker and less consistent recently. Selection patterns were strongly affected by fish age and sex, in addition to extrinsic factors including fish abundance, mesh size regulations, and fish length variability. These results revealed a more complex and changing pattern of selective harvest than the ‘larger is more vulnerable’ model, emphasizing the need for quantified, multi-year studies before conclusions can be drawn about potential evolutionary and ecological effects of fishery selection. Furthermore, the results indicate that biologically robust escapement goals and prevention of harvest of the largest individuals may help prevent negative effects of size-selective harvest. PMID:25567896
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Multi-model inference for incorporating trophic and climate uncertainty into stock assessments
NASA Astrophysics Data System (ADS)
Ianelli, James; Holsman, Kirstin K.; Punt, André E.; Aydin, Kerim
2016-12-01
Ecosystem-based fisheries management (EBFM) approaches allow a broader and more extensive consideration of objectives than is typically possible with conventional single-species approaches. Ecosystem linkages may include trophic interactions and climate change effects on productivity for the relevant species within the system. Presently, models are evolving to include a comprehensive set of fishery and ecosystem information to address these broader management considerations. The increased scope of EBFM approaches is accompanied with a greater number of plausible models to describe the systems. This can lead to harvest recommendations and biological reference points that differ considerably among models. Model selection for projections (and specific catch recommendations) often occurs through a process that tends to adopt familiar, often simpler, models without considering those that incorporate more complex ecosystem information. Multi-model inference provides a framework that resolves this dilemma by providing a means of including information from alternative, often divergent models to inform biological reference points and possible catch consequences. We apply an example of this approach to data for three species of groundfish in the Bering Sea: walleye pollock, Pacific cod, and arrowtooth flounder using three models: 1) an age-structured "conventional" single-species model, 2) an age-structured single-species model with temperature-specific weight at age, and 3) a temperature-specific multi-species stock assessment model. The latter two approaches also include consideration of alternative future climate scenarios, adding another dimension to evaluate model projection uncertainty. We show how Bayesian model-averaging methods can be used to incorporate such trophic and climate information to broaden single-species stock assessments by using an EBFM approach that may better characterize uncertainty.
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[Pollution load and the first flush effect of BOD5 and COD in urban runoff of Wenzhou City].
Wang, Jun; Bi, Chun-juan; Chen, Zhen-lou; Zhou, Dong
2013-05-01
Four typical rainfalls were monitored in two different research areas of Wenzhou Municipality. Concentrations of BOD5 and COD in six different urban runoffs were measured. In addition the event mean concentration (EMC), M (V) curve and BOD5/COD of pollutant were calculated. The results showed that concentrations of BOD5 and COD in different urban runoffs of Wenzhou ranged from ND to 69.21 mg x L(-1) and ND to 636 mg x L(-1). Concentrations of BOD5 and COD in different urban runoffs were decreasing over time, so it is greatly significant to manage the initial runoff for reducing organic pollution. Judged by EMC of BOD5 and COD in these five rainfalls, concentrations of pollutant in some urban runoffs were out of the integrated wastewater discharge standard. If these runoffs flowed into river, it would cause environmental pressure to the next level receiving water bodies. According to the M (V) curve, the first flush effect of COD in most urban runoffs was common; while the first flush effect of BOD5 was same as that of COD. The result also showed that organic pollution was serious at the beginning of runoff. The underlying surface type could affect the concentration of BOD5 and COD in urban runoff. While the results of BOD5/COD also suggested that biodegradation was considered as one of the effective ways to decrease the pollution load of organics in urban runoff, and the best management plans (BMPs) should be selected for various urban runoff types for the treatment of organic pollution.
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2011-01-01
Background The two homologous iron-binding lobes of transferrins are thought to have evolved by gene duplication of an ancestral monolobal form, but any conserved synteny between bilobal and monolobal transferrin loci remains unexplored. The important role played by transferrin in the resistance to invading pathogens makes this polymorphic gene a highly valuable candidate for studying adaptive divergence among local populations. Results The Atlantic cod genome was shown to harbour two tandem duplicated serum transferrin genes (Tf1, Tf2), a melanotransferrin gene (MTf), and a monolobal transferrin gene (Omp). Whereas Tf1 and Tf2 were differentially expressed in liver and brain, the Omp transcript was restricted to the otoliths. Fish, chicken and mammals showed highly conserved syntenic regions in which monolobal and bilobal transferrins reside, but contrasting with tetrapods, the fish transferrin genes are positioned on three different linkage groups. Sequence alignment of cod Tf1 cDNAs from Northeast (NE) and Northwest (NW) Atlantic populations revealed 22 single nucleotide polymorphisms (SNP) causing the replacement of 16 amino acids, including eight surface residues revealed by the modelled 3D-structures, that might influence the binding of pathogens for removal of iron. SNP analysis of a total of 375 individuals from 14 trans-Atlantic populations showed that the Tf1-NE variant was almost fixed in the Baltic cod and predominated in the other NE Atlantic populations, whereas the NW Atlantic populations were more heterozygous and showed high frequencies of the Tf-NW SNP alleles. Conclusions The highly conserved synteny between fish and tetrapod transferrin loci infers that the fusion of tandem duplicated Omp-like genes gave rise to the modern transferrins. The multiple nonsynonymous substitutions in cod Tf1 with putative structural effects, together with highly divergent allele frequencies among different cod populations, strongly suggest evidence for positive selection and local adaptation in trans-Atlantic cod populations. PMID:21612617
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Andersen, Øivind; De Rosa, Maria Cristina; Pirolli, Davide; Tooming-Klunderud, Ave; Petersen, Petra E; André, Carl
2011-05-25
The two homologous iron-binding lobes of transferrins are thought to have evolved by gene duplication of an ancestral monolobal form, but any conserved synteny between bilobal and monolobal transferrin loci remains unexplored. The important role played by transferrin in the resistance to invading pathogens makes this polymorphic gene a highly valuable candidate for studying adaptive divergence among local populations. The Atlantic cod genome was shown to harbour two tandem duplicated serum transferrin genes (Tf1, Tf2), a melanotransferrin gene (MTf), and a monolobal transferrin gene (Omp). Whereas Tf1 and Tf2 were differentially expressed in liver and brain, the Omp transcript was restricted to the otoliths. Fish, chicken and mammals showed highly conserved syntenic regions in which monolobal and bilobal transferrins reside, but contrasting with tetrapods, the fish transferrin genes are positioned on three different linkage groups. Sequence alignment of cod Tf1 cDNAs from Northeast (NE) and Northwest (NW) Atlantic populations revealed 22 single nucleotide polymorphisms (SNP) causing the replacement of 16 amino acids, including eight surface residues revealed by the modelled 3D-structures, that might influence the binding of pathogens for removal of iron. SNP analysis of a total of 375 individuals from 14 trans-Atlantic populations showed that the Tf1-NE variant was almost fixed in the Baltic cod and predominated in the other NE Atlantic populations, whereas the NW Atlantic populations were more heterozygous and showed high frequencies of the Tf-NW SNP alleles. The highly conserved synteny between fish and tetrapod transferrin loci infers that the fusion of tandem duplicated Omp-like genes gave rise to the modern transferrins. The multiple nonsynonymous substitutions in cod Tf1 with putative structural effects, together with highly divergent allele frequencies among different cod populations, strongly suggest evidence for positive selection and local adaptation in trans-Atlantic cod populations.
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NASA Astrophysics Data System (ADS)
Vanyushin, George
2015-04-01
Continuous long-term database (1998-2014) on the sea surface temperature (SST) comprising results of regional satellite monitoring (the Norwegian and the Barents seas) is used to resolve several applied problems. Authors have analyzed indirect influence the SST (the NOAA satellite data) on modern cod total stock biomass (abundance of the Northeast Arctic cod at age 3+). In this study, we went on the consideration of the relationship between the SST anomalies for March-April in the main spawning ground of the cod off the Lofoten islands in the Norwegian Shelf Waters and forecasting assessment of future cod generation success and its future abundance of 3 year old. Mean monthly SST and SST anomalies are computed for the selected area on the basis of the weekly SST maps which made by using the NOAA satellites data for the period 1998-2014. Comparison of the SST anomalies in the main spawning ground with abundance of the cod year class at age 3+ shows that survival of the cod generations was inhibited on the whole as negative (below -0,1C) well as positive SST anomalies (above +1,3C) during March and April. Finally, the results indicate that poor and low middle generations of cod at age 3+ (2002, 2004, 2010) occurred in years with negative or extremely high positive the SST anomalies in the spawning area. The SST anomalies in years which were close to normal significances provide conditions for appearance middle or strong generations of cod (2001-2003, 2005-2009, 2011-2013). So, the SST and SST anomalies (by the NOAA satellite data) characterize of increase in input of warm Atlantic waters which form numerous eddies along the main stream thus creating favorable conditions for spawning and development of the cod larvae and fry and provide them with food stock, finally direct influence on forming total stock biomass of cod and helping its population forecast. Key words: satellite monitoring of SST, the Northeast Arctic cod, spawning ground, forecast of the cod year class strength at age 3+.
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Climate and fishing steer ecosystem regeneration to uncertain economic futures
Blenckner, Thorsten; Llope, Marcos; Möllmann, Christian; Voss, Rudi; Quaas, Martin F.; Casini, Michele; Lindegren, Martin; Folke, Carl; Chr. Stenseth, Nils
2015-01-01
Overfishing of large predatory fish populations has resulted in lasting restructurings of entire marine food webs worldwide, with serious socio-economic consequences. Fortunately, some degraded ecosystems show signs of recovery. A key challenge for ecosystem management is to anticipate the degree to which recovery is possible. By applying a statistical food-web model, using the Baltic Sea as a case study, we show that under current temperature and salinity conditions, complete recovery of this heavily altered ecosystem will be impossible. Instead, the ecosystem regenerates towards a new ecological baseline. This new baseline is characterized by lower and more variable biomass of cod, the commercially most important fish stock in the Baltic Sea, even under very low exploitation pressure. Furthermore, a socio-economic assessment shows that this signal is amplified at the level of societal costs, owing to increased uncertainty in biomass and reduced consumer surplus. Specifically, the combined economic losses amount to approximately 120 million € per year, which equals half of today's maximum economic yield for the Baltic cod fishery. Our analyses suggest that shifts in ecological and economic baselines can lead to higher economic uncertainty and costs for exploited ecosystems, in particular, under climate change. PMID:25694626
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At-Sea Distribution and Prey Selection of Antarctic Petrels and Commercial Krill Fisheries.
Descamps, Sébastien; Tarroux, Arnaud; Cherel, Yves; Delord, Karine; Godø, Olaf Rune; Kato, Akiko; Krafft, Bjørn A; Lorentsen, Svein-Håkon; Ropert-Coudert, Yan; Skaret, Georg; Varpe, Øystein
2016-01-01
Commercial fisheries may impact marine ecosystems and affect populations of predators like seabirds. In the Southern Ocean, there is an extensive fishery for Antarctic krill Euphausia superba that is projected to increase further. Comparing distribution and prey selection of fishing operations versus predators is needed to predict fishery-related impacts on krill-dependent predators. In this context, it is important to consider not only predators breeding near the fishing grounds but also the ones breeding far away and that disperse during the non-breeding season where they may interact with fisheries. In this study, we first quantified the overlap between the distribution of the Antarctic krill fisheries and the distribution of a krill dependent seabird, the Antarctic petrel Thalassoica antarctica, during both the breeding and non-breeding season. We tracked birds from the world biggest Antarctic petrel colony (Svarthamaren, Dronning Maud Land), located >1000 km from the main fishing areas, during three consecutive seasons. The overall spatial overlap between krill fisheries and Antarctic petrels was limited but varied greatly among and within years, and was high in some periods during the non-breeding season. In a second step, we described the length frequency distribution of Antarctic krill consumed by Antarctic petrels, and compared this with results from fisheries, as well as from diet studies in other krill predators. Krill taken by Antarctic petrels did not differ in size from that taken by trawls or from krill taken by most Antarctic krill predators. Selectivity for specific Antarctic krill stages seems generally low in Antarctic predators. Overall, our results show that competition between Antarctic petrels and krill fisheries is currently likely negligible. However, if krill fisheries are to increase in the future, competition with the Antarctic petrel may occur, even with birds breeding thousands of kilometers away.
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At-Sea Distribution and Prey Selection of Antarctic Petrels and Commercial Krill Fisheries
Descamps, Sébastien; Tarroux, Arnaud; Cherel, Yves; Delord, Karine; Godø, Olaf Rune; Kato, Akiko; Krafft, Bjørn A.; Lorentsen, Svein-Håkon; Ropert-Coudert, Yan; Skaret, Georg; Varpe, Øystein
2016-01-01
Commercial fisheries may impact marine ecosystems and affect populations of predators like seabirds. In the Southern Ocean, there is an extensive fishery for Antarctic krill Euphausia superba that is projected to increase further. Comparing distribution and prey selection of fishing operations versus predators is needed to predict fishery-related impacts on krill-dependent predators. In this context, it is important to consider not only predators breeding near the fishing grounds but also the ones breeding far away and that disperse during the non-breeding season where they may interact with fisheries. In this study, we first quantified the overlap between the distribution of the Antarctic krill fisheries and the distribution of a krill dependent seabird, the Antarctic petrel Thalassoica antarctica, during both the breeding and non-breeding season. We tracked birds from the world biggest Antarctic petrel colony (Svarthamaren, Dronning Maud Land), located >1000 km from the main fishing areas, during three consecutive seasons. The overall spatial overlap between krill fisheries and Antarctic petrels was limited but varied greatly among and within years, and was high in some periods during the non-breeding season. In a second step, we described the length frequency distribution of Antarctic krill consumed by Antarctic petrels, and compared this with results from fisheries, as well as from diet studies in other krill predators. Krill taken by Antarctic petrels did not differ in size from that taken by trawls or from krill taken by most Antarctic krill predators. Selectivity for specific Antarctic krill stages seems generally low in Antarctic predators. Overall, our results show that competition between Antarctic petrels and krill fisheries is currently likely negligible. However, if krill fisheries are to increase in the future, competition with the Antarctic petrel may occur, even with birds breeding thousands of kilometers away. PMID:27533327
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Ocean acidification may aggravate social-ecological trade-offs in coastal fisheries.
Voss, Rudi; Quaas, Martin F; Schmidt, Jörn O; Kapaun, Ute
2015-01-01
Ocean Acidification (OA) will influence marine ecosystems by changing species abundance and composition. Major effects are described for calcifying organisms, which are significantly impacted by decreasing pH values. Direct effects on commercially important fish are less well studied. The early life stages of fish populations often lack internal regulatory mechanisms to withstand the effects of abnormal pH. Negative effects can be expected on growth, survival, and recruitment success. Here we study Norwegian coastal cod, one of the few stocks where such a negative effect was experimentally quantified, and develop a framework for coupling experimental data on OA effects to ecological-economic fisheries models. In this paper, we scale the observed physiological responses to the population level by using the experimentally determined mortality rates as part of the stock-recruitment relationship. We then use an ecological-economic optimization model, to explore the potential effect of rising CO2 concentration on ecological (stock size), economic (profits), consumer-related (harvest) and social (employment) indicators, with scenarios ranging from present day conditions up to extreme acidification. Under the assumptions of our model, yields and profits could largely be maintained under moderate OA by adapting future fishing mortality (and related effort) to changes owing to altered pH. This adaptation comes at the costs of reduced stock size and employment, however. Explicitly visualizing these ecological, economic and social tradeoffs will help in defining realistic future objectives. Our results can be generalized to any stressor (or stressor combination), which is decreasing recruitment success. The main findings of an aggravation of trade-offs will remain valid. This seems to be of special relevance for coastal stocks with limited options for migration to avoid unfavorable future conditions and subsequently for coastal fisheries, which are often small scale local fisheries with limited operational ranges.
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Causes of death among commercially insured multiple sclerosis patients in the United States.
Goodin, Douglas S; Corwin, Michael; Kaufman, David; Golub, Howard; Reshef, Shoshana; Rametta, Mark J; Knappertz, Volker; Cutter, Gary; Pleimes, Dirk
2014-01-01
Information on causes of death (CODs) for patients with multiple sclerosis (MS) in the United States is sparse and limited by standard categorizations of underlying and immediate CODs on death certificates. Prior research indicated that excess mortality among MS patients was largely due to greater mortality from infectious, cardiovascular, or pulmonary causes. To analyze disease categories in order to gain insight to pathways, which lead directly to death in MS patients. Commercially insured MS patients enrolled in the OptumInsight Research database between 1996 and 2009 were matched to non-MS comparators on age/residence at index year and sex. The cause most-directly leading to death from the death certificate, referred to as the "principal" COD, was determined using an algorithm to minimize the selection of either MS or cardiac/pulmonary arrest as the COD. Principal CODs were categorized into MS, cancer, cardiovascular, infectious, suicide, accidental, pulmonary, other, or unknown. Infectious, cardiovascular, and pulmonary CODs were further subcategorized. 30,402 MS patients were matched to 89,818 controls, with mortality rates of 899 and 446 deaths/100,000 person-years, respectively. Excluding MS, differences in mortality rate between MS patients and non-MS comparators were largely attributable to infections, cardiovascular causes, and pulmonary problems. Of the 95 excessive deaths (per 100,000 person-years) related to infectious causes, 41 (43.2%) were due to pulmonary infections and 45 (47.4%) were attributed to sepsis. Of the 46 excessive deaths (per 100,000 person-years) related to pulmonary causes, 27 (58.7%) were due to aspiration. No single diagnostic entity predominated for the 60 excessive deaths (per 100,000 person-years) attributable to cardiac CODs. The principal COD algorithm improved on other methods of determining COD in MS patients from death certificates. A greater awareness of the common CODs in MS patients will allow physicians to anticipate potential problems and, thereby, improve the care that they provide.
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Kastelein, Ronald A; van der Heul, Sander; van der Veen, Jan; Verboom, Willem C; Jennings, Nancy; de Haan, Dick; Reijnders, Peter J H
2007-08-01
World-wide many cetaceans drown incidentally in fishing nets. To reduce the unwanted bycatch in gillnets, pingers (acoustic alarms) have been developed that are attached to the nets. In the European Union, pingers will be made compulsory in some areas in 2005 and in others in 2007. However, pingers may effect non-target marine fauna such as fish. Therefore in this study, the effects of seven commercially-available pingers on the behaviour of five North Sea fish species in a large tank were quantified. The species tested were: sea bass (Dicentrarchus labrax), pout (Trisopterus luscus), thicklip mullet (Chelon labrosus), herring (Clupea harengus), and cod (Gadus morhua). The fish were housed as single-species schools of 9-13 individuals in a tank. The behaviour of fish in quiet periods was compared with their behaviour during periods with active pingers. The results varied both between pingers and between fish species. Sea bass decreased their speed in response to one pinger and swam closer to the surface in response to another. Thicklip mullet swam closer to the bottom in response to two pingers and increased their swimming speed in response to one pinger. Herring swam faster in response to one pinger, and pout and cod (close relatives) showed no behavioural responses to any of the pingers. Of the seven pingers tested, four elicited responses in at least one fish species, and three elicited no responses. Whether similar responses would be elicited in these fish species in the wild, and if so, whether such responses would influence the catch rate of fisheries, cannot be derived from the results of this study. However, the results indicate the need for field studies with pingers and fish. Based on the small number of fish species tested, the present study suggests that the higher the frequency of a pinger, the less likely it is to affect the behaviour of marine fish.
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Tejel, Cristina; Villarroya, B. Eva; Ciriano, Miguel A.; Oro, Luis A.; Lanfranchi, Maurizio; Tiripicchio, Antonio; Tiripicchio-Camellini, Marisa
1996-07-17
Reactions of [M(2)(&mgr;-Cl)(2)(cod)(2)] (cod = 1,5-cyclooctadiene, M = Rh, Ir) with benzimidazole-2-thiol (H(2)Bzimt) afford the mononuclear complexes [MCl(H(2)Bzimt)(cod)] (M = Rh (1), Ir (2)) for which a S-coordination of the ligand is proposed based on their spectroscopic data. The dinuclear complexes [M(2)(&mgr;-HBzimt)(2)(cod)(2)] (M = Rh (3), Ir (4)) are isolated from the reaction of [M(acac)(cod)] and benzimidazole-2-thiol. They contain the monodeprotonated ligand (HBzimt(-)) bridging the two metals in a &mgr;(2)-(1kappaN,2kappaS) coordination mode and in a relative cis,cis-HT arrangement. Complexes 3 and 4 react with the appropriate species [M(cod)(Me(2)CO)(2)](+) to afford the trinuclear cationic aggregates [M(3)(&mgr;-HBzimt)(2)(cod)(3)](+) (M = Rh (5), Ir (6)) and with the [M'(2)(&mgr;-OMe)(2)(cod)(2)] compounds to give the homo- and heterotetranuclear complexes [MM'(&mgr;-Bzimt)(cod)(2)](2) (M = M' = Rh (7), Ir (8); M = Ir, M' = Rh (9)) containing the dideprotonated ligand (Bzimt(2)(-)). The trinuclear neutral complexes [M(3)(&mgr;-Bzimt)(&mgr;-HBzimt)(cod)(3)] are intermediates detected in the synthesis of the tetranuclear complexes. Protonation of 9 with HBF(4) gives the unsymmetrical complex [Ir(2)Rh(&mgr;-HBzimt)(2)(cod)(3)]BF(4) (10). This reaction involves the protonation of the bridging ligands followed by the removal of one "Rh(cod)" moiety to give a single isomer. The molecular structure of [Rh(2)(&mgr;-Bzimt)(cod)(2)](2) (7) has been determined by X-ray diffraction methods. Crystals are monoclinic, space group P2(1)/n, a = 20.173(5) Å, b = 42.076(8) Å, c = 10.983(3) Å, beta = 93.32(2) degrees, Z = 8, 7145 reflections, R = 0.0622, and R(w) = 0.0779. The complete assignment of the resonances of the (1)H NMR spectra of the complexes 3, 4, and 7-9 was carried out by selective decoupling, NOE, and H,H-COSY experiments. The differences in the chemical shifts of the olefinic protons are discussed on the basis of steric and magnetic anisotropy effects.
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Padoley, K V; Tembhekar, P D; Saratchandra, T; Pandit, A B; Pandey, R A; Mudliar, S N
2012-09-01
This study looks at the possibility of wet air oxidation (WAO) based pretreatment of complex effluent to selectively enhance the biodegradability (without substantial COD destruction) and facilitate biogas generation potential. A lab-scale wet air oxidation reactor with biomethanated distillery wastewater (B-DWW) as a model complex effluent (COD 40,000 mg L(-1)) was used to demonstrate the proof-of-concept. The studies were conducted using a designed set of experiments and reaction temperature (150-200°C), air pressure (6-12 bar) and reaction time (15-120 min) were the main process variables of concern for WAO process optimization. WAO pretreatment of B-DWW enhanced the biodegradability of the complex wastewater by the virtue of enhancing its biodegradability index (BI) from 0.2 to 0.88, which indicate favorable Biochemical Methane Potential (BMP) for biogas generation. The kinetics of COD destruction and BI enhancement has also been reported. Copyright © 2012 Elsevier Ltd. All rights reserved.
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Damalas, Dimitrios; Maravelias, Christos D.; Osio, Giacomo C.; Maynou, Francesc; Sbrana, Mario; Sartor, Paolo
2015-01-01
We investigate long-term changes in the Mediterranean marine resources driving the trawl fisheries by analysing fishers’ perceptions (Traditional Ecological Knowledge, TEK) throughout the Mediterranean Sea during the last 80 years. To this end, we conducted an extended set of interviews with experienced fishers that enabled us to classify species (or taxa) as ‘decreasing’ or ‘increasing’ both in terms of abundance, as well as average size in the catch. The aspect that most clearly emerged in all the investigated areas over time was the notable increase of fishing capacity indicators, such as engine power and fishing depth range. Atlantic mackerel, poor cod, scorpionfishes, striped seabream, and John Dory demonstrated a decreasing trend in the fishers’ perceived abundance, while Mediterranean parrotfish, common pandora, cuttlefish, blue and red shrimp, and mullets gave indications of an increasing temporal trend. Although, as a rule, trawler captains did not report any cataclysmic changes (e.g. extinctions), when they were invited to estimate total catches, a clear decreasing pattern emerged; this being a notable finding taking into account the steep escalation of fishing efficiency during the past century. The overall deteriorating status of stocks in most Mediterranean regions calls for responsible management and design of rebuilding plans. This should include historical information accounting for past exploitation patterns that could help defining a baseline of fish abundance prior to heavy industrial fisheries exploitation. PMID:25781459
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50 CFR 86.62 - What must I do after my project has been selected?
Code of Federal Regulations, 2010 CFR
2010-10-01
... 50 Wildlife and Fisheries 6 2010-10-01 2010-10-01 false What must I do after my project has been selected? 86.62 Section 86.62 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE, DEPARTMENT OF... INFRASTRUCTURE GRANT (BIG) PROGRAM How the Service Selects Projects To Receive Grants § 86.62 What must I do...
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50 CFR 86.63 - May I appeal if my project is not selected?
Code of Federal Regulations, 2010 CFR
2010-10-01
... 50 Wildlife and Fisheries 6 2010-10-01 2010-10-01 false May I appeal if my project is not selected? 86.63 Section 86.63 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE, DEPARTMENT OF THE... GRANT (BIG) PROGRAM How the Service Selects Projects To Receive Grants § 86.63 May I appeal if my...
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Production of Spirulina sp by utilization of wastewater from the powder type energy drinks
NASA Astrophysics Data System (ADS)
Sumantri, Indro; Priyambada, Ika Bagus
2015-12-01
Wastewater of energy drink type of powder produced when the the production equipment required cleaning treatment to produce one taste to others. These equipments washed by water, so that, it produced wastewater. It contains high organic substances and classified as high degradable due to food product. The content of wastewater is high carbon and nitrogen substances. Microalgae is an autotrophic microorganism, live without carbon presence, utilized to digest the substances in wastewater especially for nitrogen substances. Spirulina sp is the type of microalgae selected to utilize the wastewater of energy drink, the selection criteria is the size of Spirulina sp is relatively large and easy to separated from its solution. The experiment conducted by cultivate the seeding microalgae with certain nutrients until the certain volume. The synthetic wastewater obtained from one of energy drink type of powder with commercial brand as Kuku Bima Ener-G, the wastewater concentration selected under the close to the real condition of wastewater as basis of COD measurement (6 sachet/L or COD of 12.480mg/L) and aqueous concentration (1 sachet/L or COD of 2080mg/L). The batch experiments with 1L volume conducted and with variable of percent volume of wastewater added in order to observe the growth of microlagae. The response of the microalgae growth obtained by increasing the optical density of the microalgae solution and continued by calculation for the growth rate of microalgae. The result of the experiments indicated that for the aqueous concentration (1 sachet/L or COD of 2080mg/L) the optimum added of wastewater is 40 % with growrate of 0.55/day while for the concentrated wastewater (6 sachet/L or COD of 12.480mg/L), the optimum condition is 25 % wastewater added with growth rate of 0.43/day.
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NASA Astrophysics Data System (ADS)
Tuukkanen, T.; Marttila, H.; Kløve, B.
2017-07-01
Organic matter and nutrient export from drained peatlands is affected by complex hydrological and biogeochemical interactions. Here partial least squares regression (PLSR) was used to relate various soil and catchment characteristics to variations in chemical oxygen demand (COD), total nitrogen (TN), and total phosphorus (TP) concentrations in runoff. Peat core samples and water quality data were collected from 15 peat extraction sites in Finland. PLSR models constructed by cross-validation and variable selection routines predicted 92, 88, and 95% of the variation in mean COD, TN, and TP concentration in runoff, respectively. The results showed that variations in COD were mainly related to net production (temperature and water-extractable dissolved organic carbon (DOC)), hydrology (topographical relief), and solubility of dissolved organic matter (peat sulfur (S) and calcium (Ca) concentrations). Negative correlations for peat S and runoff COD indicated that acidity from oxidation of organic S stored in peat may be an important mechanism suppressing organic matter leaching. Moreover, runoff COD was associated with peat aluminum (Al), P, and sodium (Na) concentrations. Hydrological controls on TN and COD were similar (i.e., related to topography), whereas degree of humification, bulk density, and water-extractable COD and Al provided additional explanations for TN concentration. Variations in runoff TP concentration were attributed to erosion of particulate P, as indicated by a positive correlation with suspended sediment concentration (SSC), and factors associated with metal-humic complexation and P adsorption (peat Al, water-extractable P, and water-extractable iron (Fe)).
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50 CFR 665.664 - Gear restrictions.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false Gear restrictions. 665.664 Section 665.664 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION... § 665.664 Gear restrictions. Only selective gear may be used to harvest coral from any precious coral...
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50 CFR 665.464 - Gear restrictions.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false Gear restrictions. 665.464 Section 665.464 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION... Gear restrictions. Only selective gear may be used to harvest coral from any precious coral permit area. ...
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[Measurement of Water COD Based on UV-Vis Spectroscopy Technology].
Wang, Xiao-ming; Zhang, Hai-liang; Luo, Wei; Liu, Xue-mei
2016-01-01
Ultraviolet/visible (UV/Vis) spectroscopy technology was used to measure water COD. A total of 135 water samples were collected from Zhejiang province. Raw spectra with 3 different pretreatment methods (Multiplicative Scatter Correction (MSC), Standard Normal Variate (SNV) and 1st Derivatives were compared to determine the optimal pretreatment method for analysis. Spectral variable selection is an important strategy in spectrum modeling analysis, because it tends to parsimonious data representation and can lead to multivariate models with better performance. In order to simply calibration models, the preprocessed spectra were then used to select sensitive wavelengths by competitive adaptive reweighted sampling (CARS), Random frog and Successive Genetic Algorithm (GA) methods. Different numbers of sensitive wavelengths were selected by different variable selection methods with SNV preprocessing method. Partial least squares (PLS) was used to build models with the full spectra, and Extreme Learning Machine (ELM) was applied to build models with the selected wavelength variables. The overall results showed that ELM model performed better than PLS model, and the ELM model with the selected wavelengths based on CARS obtained the best results with the determination coefficient (R2), RMSEP and RPD were 0.82, 14.48 and 2.34 for prediction set. The results indicated that it was feasible to use UV/Vis with characteristic wavelengths which were obtained by CARS variable selection method, combined with ELM calibration could apply for the rapid and accurate determination of COD in aquaculture water. Moreover, this study laid the foundation for further implementation of online analysis of aquaculture water and rapid determination of other water quality parameters.
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76 FR 16385 - Gulf of Mexico Fishery Management Council; Public Meetings
Federal Register 2010, 2011, 2012, 2013, 2014
2011-03-23
... INFORMATION CONTACT: Dr. Stephen Bortone, Executive Director, Gulf of Mexico Fishery Management Council...; Scientific & Statistical Committee Selection; and Reef Fish. 3:45 p.m.-4:15 p.m.--Other Business items will....--Closed Session--The Scientific & Statistical Committees Selection Committee/Full Council will meet to...
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Electrooxidation of industrial wastewater containing 1,4-dioxane in the presence of different salts.
Barndõk, H; Hermosilla, D; Cortijo, L; Torres, E; Blanco, A
2014-04-01
The treatment of 1,4-dioxane solution by electrochemical oxidation on boron-doped diamond was studied using a central composite design and the response surface methodology to investigate the use of SO4 (2-) and HCO3 (-) as supporting electrolytes considering the applied electric current, initial chemical oxygen demand (COD) value, and treatment time. Two industrial effluents containing bicarbonate alkalinity, one just carrying 1,4-dioxane (S1), and another one including 1,4-dioxane and 2-methyl-1,3-dioxolane (S2), were treated under optimized conditions and subsequently subjected to biodegradability assays with a Pseudomonas putida culture. Electrooxidation was compared with ozone oxidation (O3) and its combination with hydrogen peroxide (O3/H2O2). Regarding the experimental design, the optimal compromise for maximum COD removal at minimum energy consumption was shown at the maximum tested concentrations of SO4 (2-) and HCO3 (-) (41.6 and 32.8 mEq L(-1), respectively) and the maximum selected initial COD (750 mg L(-1)), applying a current density of 11.9 mA cm(-2) for 3.8 h. Up to 98 % of the COD was removed in the electrooxidation treatment of S1 effluent using 114 kWh per kg of removed COD and about 91 % of the COD from S2 wastewater applying 49 kWh per kg of removed COD. The optimal biodegradability enhancement was achieved after 1 h of electrooxidation treatment. In comparison with O3 and O3/H2O2 alternatives, electrochemical oxidation achieved the fastest degradation rate per oxidant consumption unit, and it also resulted to be the most economical treatment in terms of energy consumption and price per unit of removed COD.
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Seasonal Temperature Estimates From Late Holocene Barents Sea cod Otoliths: Problems and Potential
NASA Astrophysics Data System (ADS)
Andersson, C.; Folkvord, A.; Geffen, A.; Høie, H.
2008-12-01
Realistic models of climate change require accurate data of past seasonal temperature regimes. In many marine settings this is difficult to achieve using the marine sedimentary record. This study tests the feasibility to use archaeological cod otoliths to reconstruct changes in the seasonal temperature cycle in the Barents Sea. Potentially, stable oxygen isotope records from cod otoliths could be used to produce records of Holocene temperature change on a seasonal time scale. Human settlements along the coast of northern Norway have exploited the cod (Gadus morhua) population of the Barents Sea from the earliest occupation, through the middle ages, to the present day. A pilot project has been carried out in Bergen to exploit the availability of a collection of cod otoliths from archeological excavations that is housed by the Bergen Museum. Cod otoliths from archaeological excavations in northern Norway, 26 specimens from from Måsøy (Finnmark) and 17 specimens from Vanna (Troms), were selected for this study. These specimens were AMS radiocarbon dated and the ages are spanning approximately 1400 to 1780 AD. Most of the otoliths are from cod that were captured during the Little Ice Age. Seasonal growth patterns were identifiable in the archeological otoliths, comparable to those in modern otoliths. Micromilling was used to sample for stable oxygen isotopes over a 2-year growth period in each of a total of 43 fossil cod otoliths. There are large differences in the temperature ranges experienced by the fish over the 2-year period analyzed. For the Måsøy specimens the temperature range experienced by the fish is between 2.7 to 9.9 °C. The Vanna cod experienced temperature ranges between 1.7 to 7.2 °C. The maximum temperature ranges for both Vanna and Måsøy specimens are higher than the seasonal instrumental measurements for the 0-200 m depth interval in the Kola section in the Barents Sea. The cod otoliths in our study have not yet been divided into different age groups, which is necessary in order to be able to interpret the calculated temperature ranges because the annual temperature cycles experienced by fish at different ages are different. Another problem that needs to address is the annual migration of cod of northern Norway. It is known that both mature and immature cod undertake long seasonal migrations.
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50 CFR 665.264 - Gear restrictions.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false Gear restrictions. 665.264 Section 665.264..., DEPARTMENT OF COMMERCE (CONTINUED) FISHERIES IN THE WESTERN PACIFIC Hawaii Fisheries § 665.264 Gear restrictions. Only selective gear may be used to harvest coral from any precious coral permit area. ...
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50 CFR 665.164 - Gear restrictions.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false Gear restrictions. 665.164 Section 665.164..., DEPARTMENT OF COMMERCE (CONTINUED) FISHERIES IN THE WESTERN PACIFIC American Samoa Fisheries § 665.164 Gear restrictions. Only selective gear may be used to harvest coral from any precious coral permit area. ...
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NASA Technical Reports Server (NTRS)
Kemmerer, A. J.; Benigno, J. A.
1973-01-01
The author has identified the following significant results. A feasibility study to demonstrate the potential of satellites for providing fisheries significant information was conducted in the Mississippi Sound and adjacent offshore waters. Attempts were made to relate satellite acquired imagery to selected oceanographic parameters and then to relate these parameters to aircraft remotely sensed distribution patterns of resident surface schooling fishes. Initial results suggest that this approach is valid and that the satellite acquired imagery may have important fisheries resource assessment implications.
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Zhang, Zhenchao
2017-12-01
In this study, a combined process was developed that included micro-electrolysis, Fenton oxidation and coagulation to treat oilfield fracturing wastewater. Micro-electrolysis and Fenton oxidation were applied to reduce chemical oxygen demand (COD) organic load and to enhance organic components gradability, respectively. Orthogonal experiment were employed to investigate the influence factors of micro-electrolysis and Fenton oxidation on COD removal efficiency. For micro-electrolysis, the optimum conditions were: pH, 3; iron-carbon dosage, 50 mg/L; mass ratio of iron-carbon, 2:3; reaction time, 60 min. For Fenton oxidation, a total reaction time of 90 min, a H 2 O 2 dosage of 12 mg/L, with a H 2 O 2 /Fe 2+ mole ratio of 30, pH of 3 were selected to achieve optimum oxidation. The optimum conditions in coagulation process: pH, cationic polyacrylamide dosage, mixing speed and time is 4.3, 2 mg/L, 150 rpm and 30 s, respectively. In the continuous treatment process under optimized conditions, the COD of oily wastewater fell 56.95%, 46.23%, 30.67%, respectively, from last stage and the total COD removal efficiency reached 83.94% (from 4,314 to 693 mg/L). In the overall treatment process under optimized conditions, the COD of oily wastewater was reduced from 4,314 to 637 mg/L, and the COD removal efficiency reached 85.23%. The contribution of each stage is 68.45% (micro-electrolysis), 24.07% (Fenton oxidation), 7.48% (coagulation), respectively. Micro-electrolysis is the uppermost influencing process on COD removal. Compared with the COD removal efficiency of three processes on raw wastewater under optimized conditions: the COD removal efficiency of single micro-electrolysis, single Fenton oxidation, single coagulation is 58.34%, 44.88% and 39.72%, respectively. Experiments proved the effect of combined process is marvelous and the overall water quality of the final effluent could meet the class III national wastewater discharge standard of petrochemical industry of China (GB8978-1996).
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Digre, Hanne; Erikson, Ulf; Aursand, Ida G; Gallart-Jornet, Lorena; Misimi, Ekrem; Rustad, Turid
2011-01-01
The main objectives of this study were to investigate (1) whether rested harvest of farmed cod was better maintained by chilling with slurry rather than by traditional ice storage, (2) whether chilling with slurry would be a feasible chilling method to assure low core temperatures (≤0 °C) at packing of gutted fish, and (3) the effects of superchilling compared with traditional ice on selected quality parameters of cod during storage. In the experiment, seawater slurry at -2.0 ± 0.3 °C was used. Anesthetized (AQUI-S™), percussion stunned, and stressed cod chilled in slurry were compared. Cod stored on ice were used as reference group. The fish were evaluated at the day of slaughter, and after 7 and 14 d of storage according to handling stress (initial muscle pH, muscle twitches, rigor mortis), core temperatures, quality index method, microbial counts, weight changes, salt and water content, water distribution, pH, adenosine triphosphate-degradation products, K-value, water-holding capacity, fillet color, and texture. Chilling cod in slurry was more rapid than chilling in ice. Prechilling (1 d) of cod in slurry before subsequent ice storage resulted in lower quality 7 d postmortem compared with both ice and continuous slurry storage. The potential advantages of superchilling became more prominent after 14 d with lower microbiological activity, better maintenance of freshness (lower total quality index scores and lower K-values) compared with fish stored on ice. A drawback with slurry-stored fish was that cloudy eyes developed earlier, in addition to weight gain and salt uptake compared to ice-stored fish. Practical Application: Chilling is an essential operation in any fish-processing plant. This manuscript addresses different applications of slurry ice in the processing and storage of Atlantic cod. Cod quality was assessed after 7 and 14 d of iced and superchilled storage.
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Lade, Steven J; Niiranen, Susa; Hentati-Sundberg, Jonas; Blenckner, Thorsten; Boonstra, Wiebren J; Orach, Kirill; Quaas, Martin F; Österblom, Henrik; Schlüter, Maja
2015-09-01
Regime shifts triggered by human activities and environmental changes have led to significant ecological and socioeconomic consequences in marine and terrestrial ecosystems worldwide. Ecological processes and feedbacks associated with regime shifts have received considerable attention, but human individual and collective behavior is rarely treated as an integrated component of such shifts. Here, we used generalized modeling to develop a coupled social-ecological model that integrated rich social and ecological data to investigate the role of social dynamics in the 1980s Baltic Sea cod boom and collapse. We showed that psychological, economic, and regulatory aspects of fisher decision making, in addition to ecological interactions, contributed both to the temporary persistence of the cod boom and to its subsequent collapse. These features of the social-ecological system also would have limited the effectiveness of stronger fishery regulations. Our results provide quantitative, empirical evidence that incorporating social dynamics into models of natural resources is critical for understanding how resources can be managed sustainably. We also show that generalized modeling, which is well-suited to collaborative model development and does not require detailed specification of causal relationships between system variables, can help tackle the complexities involved in creating and analyzing social-ecological models.
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Lade, Steven J.; Niiranen, Susa; Hentati-Sundberg, Jonas; Blenckner, Thorsten; Boonstra, Wiebren J.; Orach, Kirill; Quaas, Martin F.; Österblom, Henrik; Schlüter, Maja
2015-01-01
Regime shifts triggered by human activities and environmental changes have led to significant ecological and socioeconomic consequences in marine and terrestrial ecosystems worldwide. Ecological processes and feedbacks associated with regime shifts have received considerable attention, but human individual and collective behavior is rarely treated as an integrated component of such shifts. Here, we used generalized modeling to develop a coupled social–ecological model that integrated rich social and ecological data to investigate the role of social dynamics in the 1980s Baltic Sea cod boom and collapse. We showed that psychological, economic, and regulatory aspects of fisher decision making, in addition to ecological interactions, contributed both to the temporary persistence of the cod boom and to its subsequent collapse. These features of the social–ecological system also would have limited the effectiveness of stronger fishery regulations. Our results provide quantitative, empirical evidence that incorporating social dynamics into models of natural resources is critical for understanding how resources can be managed sustainably. We also show that generalized modeling, which is well-suited to collaborative model development and does not require detailed specification of causal relationships between system variables, can help tackle the complexities involved in creating and analyzing social–ecological models. PMID:26283344
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Cod Gadus morhua and climate change: processes, productivity and prediction.
Brander, K M
2010-11-01
Environmental factors act on individual fishes directly and indirectly. The direct effects on rates and behaviour can be studied experimentally and in the field, particularly with the advent of ever smarter tags for tracking fishes and their environment. Indirect effects due to changes in food, predators, parasites and diseases are much more difficult to estimate and predict. Climate can affect all life-history stages through direct and indirect processes and although the consequences in terms of growth, survival and reproductive output can be monitored, it is often difficult to determine the causes. Investigation of cod Gadus morhua populations across the whole North Atlantic Ocean has shown large-scale patterns of change in productivity due to lower individual growth and condition, caused by large-scale climate forcing. If a population is being heavily exploited then a drop in productivity can push it into decline unless the level of fishing is reduced: the idea of a stable carrying capacity is a dangerous myth. Overexploitation can be avoided by keeping fishing mortality low and by monitoring and responding rapidly to changes in productivity. There are signs that this lesson has been learned and that G. morhua will continue to be a mainstay of the human diet. © 2010 The Author. Journal of Fish Biology © 2010 The Fisheries Society of the British Isles.
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76 FR 3616 - Gulf of Mexico Fishery Management Council; Public Meetings
Federal Register 2010, 2011, 2012, 2013, 2014
2011-01-20
... permits (EFPs), if any and hold an open public comment period regarding any fishery issue of concern... Policy; Habitat Protection; SEDAR Selection; AP Selection; Data Collection; Budget/Personnel; Shrimp... Essential Fish Habitat 5-year Review Report. 4:15 p.m.-4:45 p.m.--The Data Collection committee will meet to...
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Effect of Codend Circumference on the Size Selection of Square-Mesh Codends in Trawl Fisheries
De Carlo, Francesco; Lucchetti, Alessandro
2016-01-01
It is well established that increasing mesh number in the circumference of a diamond-mesh trawl codend can reduce size selection for round fish, whereas selection for flat fish species is unaffected. This effect has also been documented in Mediterranean trawl fisheries. In contrast, no information is available with regard to the effect of increasing mesh number in the circumference of square-mesh codends on the size selection of round fish and flat fish species. A field study was devised to bridge this gap and formulate proposals aimed at improving trawl fishery management. Size selection data were collected for a round fish species, red mullet (Mullus barbatus), and two flat fish species, Mediterranean scaldfish (Arnoglossus laterna) and solenette (Buglossidium luteum). Fishing trials were conducted in the Adriatic Sea (Central Mediterranean) using three square-mesh codends that differed only in mesh number around the circumference. Results demonstrated that increasing the number of meshes from 107 to 213 reduced the 50% retention length (L50) for red mullet by 2.5 cm but did not affect size selection for the two flat fish species. In some fisheries, regulatory provisions regarding the number of meshes in the circumference should therefore be carefully considered both for diamond- and square-mesh codends. PMID:27472058
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Bradshaw, Debbie; Groenewald, Pamela; Bourne, David E.; Mahomed, Hassan; Nojilana, Beatrice; Daniels, Johan; Nixon, Jo
2006-01-01
OBJECTIVE: To review the quality of the coding of the cause of death (COD) statistics and assess the mortality information needs of the City of Cape Town. METHODS: Using an action research approach, a study was set up to investigate the quality of COD information, the accuracy of COD coding and consistency of coding practices in the larger health subdistricts. Mortality information needs and the best way of presenting the statistics to assist health managers were explored. FINDINGS: Useful information was contained in 75% of death certificates, but nearly 60% had only a single cause certified; 55% of forms were coded accurately. Disagreement was mainly because routine coders coded the immediate instead of the underlying COD. An abridged classification of COD, based on causes of public health importance, prevalent causes and selected combinations of diseases was implemented with training on underlying cause. Analysis of the 2001 data identified the leading causes of death and premature mortality and illustrated striking differences in the disease burden and profile between health subdistricts. CONCLUSION: Action research is particularly useful for improving information systems and revealed the need to standardize the coding practice to identify underlying cause. The specificity of the full ICD classification is beyond the level of detail on the death certificates currently available. An abridged classification for coding provides a practical tool appropriate for local level public health surveillance. Attention to the presentation of COD statistics is important to enable the data to inform decision-makers. PMID:16583080
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Bradshaw, Debbie; Groenewald, Pamela; Bourne, David E; Mahomed, Hassan; Nojilana, Beatrice; Daniels, Johan; Nixon, Jo
2006-03-01
To review the quality of the coding of the cause of death (COD) statistics and assess the mortality information needs of the City of Cape Town. Using an action research approach, a study was set up to investigate the quality of COD information, the accuracy of COD coding and consistency of coding practices in the larger health subdistricts. Mortality information needs and the best way of presenting the statistics to assist health managers were explored. Useful information was contained in 75% of death certificates, but nearly 60% had only a single cause certified; 55% of forms were coded accurately. Disagreement was mainly because routine coders coded the immediate instead of the underlying COD. An abridged classification of COD, based on causes of public health importance, prevalent causes and selected combinations of diseases was implemented with training on underlying cause. Analysis of the 2001 data identified the leading causes of death and premature mortality and illustrated striking differences in the disease burden and profile between health subdistricts. Action research is particularly useful for improving information systems and revealed the need to standardize the coding practice to identify underlying cause. The specificity of the full ICD classification is beyond the level of detail on the death certificates currently available. An abridged classification for coding provides a practical tool appropriate for local level public health surveillance. Attention to the presentation of COD statistics is important to enable the data to inform decision-makers.
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NASA Astrophysics Data System (ADS)
Kon, Hisao; Watanabe, Masahiro
This study focuses on effluent COD concentration from wastewater treatment in regards to the reduction of pathogenic bacteria and trace substances in public waters. The main types of secondary wastewater treatment were conventional activated sludge processes. Recently, however, advance wastewater treatment processes have been developed aimed at the removal of nitrogen and phosphorus, and the effluent quality of these processes was analyzed in this study. Treatment processes for water reclamation that make effluent to meet the target water quality for reuse purposes were selected and also optimum design parameters for these processes were proposed. It was found that the treatment cost to water reclamation was greatly affected by the effluent COD of the secondary treatment. It is important to maintain low COD concentration in the secondary treated effluent. Therefore, it is considered that adequate cost benefits would be obtained by achieving target COD quality through shifting from a conventional activated sludge process to an advanced treatment process.
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Raeissi, Pouran; Sharifi, Marziye; Khosravizadeh, Omid; Heidari, Mohammad
2017-01-01
Background: Patient safety culture plays an important role in healthcare systems, especially in chemotherapy and oncology departments (CODs), and its assessment can help to improve quality of services and hospital care. Objective: This study aimed to evaluate and compare items and dimensions of patient safety culture in the CODs of selected teaching hospitals of Iran and Tehran University of Medical Sciences. Materials and Methods: This descriptive-analytical cross-sectional survey was conducted during a six-month period on 270 people from chemotherapy and oncology departments selected through a cluster sampling method. All participants answered the standard questionnaire for “Hospital Survey of Patient Safety Culture” (HSOPSC). Statistical analyses were performed using SPSS/18 software. Results: The average score for patient safety culture was three for the majority of the studied CODs. Statistically significant differences were observed for supervisor actions, teamwork within various units, feedback and communications about errors, and the level of hospital management support. (p<0.05). Relationships between studied hospitals and patient safety culture were not statistically significant (p>0.05). Conclusion: Our results showed that the overall status of patient safety culture is not good in the studied CODs. In particular, teamwork across different units and organizational learning with continuous improvement were the only two properly operating items among 12 dimensions of patient safety culture. Therefore, systematic interventions are strongly required to promote communication. PMID:29072411
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The mass balance of production and consumption: Supporting policy-makers for aquatic food security
NASA Astrophysics Data System (ADS)
Lopes, A. S.; Ferreira, J. G.; Vale, C.; Johansen, J.
2017-03-01
This work addresses divergences between data on consumption and availability for wild-caught and farmed fish, and normalisation of reported production data, to support integrated fisheries and aquaculture management. The methodologies developed, centred on improved parameterisation and on mass balance closure, were tested in two case studies: (i) the cod fishery in Europe, with particular emphasis on Iceland and the United Kingdom; and (ii) the overall balance of aquatic products for Portugal, the ICES member with the most diverse range of landed marine species. Data for consumption, Illegal, Unreported, or Unregulated (IUU) catch, and official availability statistics were used to identify discrepancies between consumption and official availability data. The identification of discrepancies between supply and demand, when coupled with source-discriminated data, showed a pattern where products with no unmet demand tend to display a considerable IUU percentage-above 9% in three cases (hake, sardine, and horse mackerel). By contrast with fished products with an over-met demand such as cod (144%) and sardine (124%), farmed species display low Optimal Consumption Level (OCL) satisfaction. Atlantic salmon, gilthead seabream, and European seabass register 45%, 58% and 44% respectively; this suggests a considerable unmet demand for these products and/or a high volume of undeclared fish reaching consumers, which may be due to the lack of landings control that exists for wild-caught fish. Improvements to production estimates using live-weight coefficients illustrate the impacts of seafood processing. Different processing methods can generate variations in live-weight estimates, leading to errors in officially reported data, and expose the limitations of the current statistical methods. As an example, the corrected per capita consumption for Portugal for 2014 (the latest FAO data) increases from 57 to 66 kg ind-1 y-1, which places the country as the second-greatest consumer in the world, well above both Malaysia and South Korea (each with 58 kg ind-1 y-1). The corrected data show that Portugal had the highest consumption rate in the world until the mid-1970's, when it was overtaken by Iceland for reasons discussed herein. The lack of detailed per-species consumption data, as well as the grouping of species by commodities, hinders a more detailed seafood consumption analysis, required by policy makers and stakeholders to effectively develop management measures to reduce illegal fishing or bycatch, and to correctly formulate strategic options for development of aquaculture and fisheries, necessary for ensuring food security over the next decades.
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Catch, bycatch and discards of the Galapagos Marine Reserve small-scale handline fishery.
Zimmerhackel, Johanna S; Schuhbauer, Anna C; Usseglio, Paolo; Heel, Lena C; Salinas-de-León, Pelayo
2015-01-01
Fisheries bycatch is a significant marine conservation issue as valuable fish are wasted and protected species harmed with potential negative ecological and socio-economic consequences. Even though there are indications that the small-scale handline fishery of the Galapagos Marine Reserve has a low selectivity, information on its bycatch has never been published. We used onboard monitoring and interview data to assess the bycatch of the Galapagos handline fishery by estimating the bycatch ratio, determining species compositions of landings and bycatch, identifying fishers' reasons for discarding certain individuals, and revealing historical trends in the bycatch ratio. The estimated bycatch ratio as a function of biomass of 0.40 and a diverse species composition of target catch and bycatch confirmed the low selectivity of this fishery. Most individuals were not landed for economic motivations, either because species (77.4%) or sizes (17.7%) are unmarketable or for regulatory reasons (5.9%). We found that bycatch contributes to growth overfishing of some target species because they are discarded or used as bait before reaching their first maturity. Moreover, over half of interviewees perceived a historical decrease in bycatch ratios that was explained by a diversification of the target catch due to the reduction in abundance of the traditionally most important target species. As some target species show signs of overfishing and to date there are no specific regulations for the finfish fishery species in place, we recommend the implementation of a series of management measures to protect critical life stages of overexploited species and to improve the selectivity of the Galapagos handline fishery.
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Catch, bycatch and discards of the Galapagos Marine Reserve small-scale handline fishery
Schuhbauer, Anna C.; Usseglio, Paolo; Heel, Lena C.; Salinas-de-León, Pelayo
2015-01-01
Fisheries bycatch is a significant marine conservation issue as valuable fish are wasted and protected species harmed with potential negative ecological and socio-economic consequences. Even though there are indications that the small-scale handline fishery of the Galapagos Marine Reserve has a low selectivity, information on its bycatch has never been published. We used onboard monitoring and interview data to assess the bycatch of the Galapagos handline fishery by estimating the bycatch ratio, determining species compositions of landings and bycatch, identifying fishers’ reasons for discarding certain individuals, and revealing historical trends in the bycatch ratio. The estimated bycatch ratio as a function of biomass of 0.40 and a diverse species composition of target catch and bycatch confirmed the low selectivity of this fishery. Most individuals were not landed for economic motivations, either because species (77.4%) or sizes (17.7%) are unmarketable or for regulatory reasons (5.9%). We found that bycatch contributes to growth overfishing of some target species because they are discarded or used as bait before reaching their first maturity. Moreover, over half of interviewees perceived a historical decrease in bycatch ratios that was explained by a diversification of the target catch due to the reduction in abundance of the traditionally most important target species. As some target species show signs of overfishing and to date there are no specific regulations for the finfish fishery species in place, we recommend the implementation of a series of management measures to protect critical life stages of overexploited species and to improve the selectivity of the Galapagos handline fishery. PMID:26082874
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ERIC Educational Resources Information Center
Menzies, Charles R.; Butler, Caroline F.
2007-01-01
The historical abundance of salmon along the west coast of North America has been significantly reduced during the last two centuries of industrial harvest. The life histories of many twentieth-century fisheries have been depressingly similar: initial coexistence with indigenous fisheries; emergence of large-scale industrial expansion followed by…
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Langford, Katherine H; Reid, Malcolm J; Fjeld, Eirik; Øxnevad, Sigurd; Thomas, Kevin V
2015-07-01
Eight organic UV filters and stabilizers were quantitatively determined in wastewater sludge and effluent, landfill leachate, sediments, and marine and freshwater biota. Crab, prawn and cod from Oslofjord, and perch, whitefish and burbot from Lake Mjøsa were selected in order to evaluate the potential for trophic accumulation. All of the cod livers analysed were contaminated with at least 1 UV filter, and a maximum concentration of almost 12 μg/g wet weight for octocrylene (OC) was measured in one individual. 80% of the cod livers contained OC, and approximately 50% of cod liver and prawn samples contained benzophenone (BP3). Lower concentrations and detection frequencies were observed in freshwater species and the data of most interest is the 4 individual whitefish that contained both BP3 and ethylhexylmethoxycinnamate (EHMC) with maximum concentrations of almost 200 ng/g wet weight. The data shows a difference in the loads of UV filters entering receiving water dependent on the extent of wastewater treatment. Primary screening alone is insufficient for the removal of selected UV filters (BP3, Padimate, EHMC, OC, UV-234, UV-327, UV-328, UV-329). Likely due in part to the hydrophobic nature of the majority of the UV filters studied, particulate loading and organic carbon content appear to be related to concentrations of UV filters in landfill leachate and an order of magnitude difference in these parameters correlates with an order of magnitude difference in the effluent concentrations of selected UV filters (Fig. 2). From the data, it is possible that under certain low flow conditions selected organic UV filters may pose a risk to surface waters but under the present conditions the risk is low, but some UV filters will potentially accumulate through the trophic food chain. Copyright © 2015. Published by Elsevier Ltd.
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Aspmo, Stein Ivar; Horn, Svein Jarle; Eijsink, Vincent G H
2005-07-01
Hydrolysates of cod viscera were tested as an alternative to commonly used complex nitrogen sources (peptones and/or extracts) for the type strains of the lactic acid bacteria Lactococcus lactis, Lactobacillus acidophilus, Lactobacillus helveticus, Lactobacillus casei, Lactobacillus sakei and Pediococcus pentosaceus. Comparative studies with MRS-like media containing different nitrogen sources showed that all the fish hydrolysates performed equally well or better than commercial extracts/peptones for all selected lactic acid bacteria.
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Gori, Riccardo; Jiang, Lu-Man; Sobhani, Reza; Rosso, Diego
2011-11-15
Most wastewater treatment plants monitor routinely carbonaceous and nitrogenous load parameters in influent and effluent streams, and often in the intermediate steps. COD fractionation discriminates the selective removal of VSS components in different operations, allowing accurate quantification of the energy requirements and mass flows for secondary treatment, sludge digestion, and sedimentation. We analysed the different effects of COD fractions on carbon and energy footprint in a wastewater treatment plant with activated sludge in nutrient removal mode and anaerobic digestion of the sludge with biogas energy recovery. After presenting a simple rational procedure for COD and solids fractions quantification, we use our carbon and energy footprint models to quantify the effects of varying fractions on carbon equivalent flows, process energy demand and recovery. A full-scale real process was modelled with this procedure and the results are reported in terms of energy and carbon footprint. For a given process, the increase of the ratio sCOD/COD increases the energy demand on the aeration reactors, the associated CO(2) direct emission from respiration, and the indirect emission for power generation. Even though it appears as if enhanced primary sedimentation is a carbon and energy footprint mitigation practice, care must be used since the nutrient removal process downstream may suffer from an excessive bCOD removal and an increased mean cell retention time for nutrient removal may be required. Copyright © 2011 Elsevier Ltd. All rights reserved.
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Eide, M; Karlsen, O A; Kryvi, H; Olsvik, P A; Goksøyr, A
2014-08-01
The Atlantic cod (Gadus morhua) is an economically important species commonly consumed by humans. The widespread distribution of cod in the North Atlantic Ocean makes it vulnerable to effluents from human activities, such as coastal industries and offshore petroleum exploration. It has been demonstrated that many effluents have adverse effects on cod reproduction and health, e.g. by disrupting endocrine signaling pathways. The liver, expressing important components of the biotransformation and the endocrine system, is one of the main target organs. Thus, reliable and reproducible in vitro systems of the liver are important for studying effects of environmental contaminants. The aim of this study was to investigate precision-cut liver slices (PCLS) as an alternative in vitro system for toxicological studies of the Atlantic cod liver. Slices of 8 mm in diameter and 250 μm thickness were prepared and cultivated from immature cod. Several analyses to measure the liver slice viability were performed: enzyme assays, histology, and morphometric analysis, all confirming cell viability for up to 72 h in culture. The liver slices were also exposed to two well-known model environmental contaminants, β-naphthoflavone (BNF) and 17α-ethynylestradiol (EE2), representing established agonists for the aryl hydrocarbon receptor (AHR) and the estrogen receptor (ER), respectively. The results showed increased transcription of the target genes cytochrome P450 1A (CYP1A) and vitellogenin (VTG), both well-established biomarkers for exposure of fish to the selected compounds. In conclusion, PCLS is a promising in vitro system for toxicological studies of cod liver cells. The liver slices are viable in culture for several days and respond to environmental contaminants in a dose- and time-specific manner. Copyright © 2013 Elsevier B.V. All rights reserved.
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Kilpeläinen, Tuomas P; Mäkinen, Tuukka; Karhunen, Pekka J; Aro, Jussi; Lahtela, Jorma; Taari, Kimmo; Talala, Kirsi; Tammela, Teuvo L J; Auvinen, Anssi
2016-12-01
Precise cause of death (CoD) ascertainment is crucial in any cancer screening trial to avoid bias from misclassification due to excessive recording of diagnosed cancer as a CoD in death certificates instead of non-cancer disease that actually caused death. We estimated whether there was bias in CoD determination between screening (SA) and control arms (CA) in a population-based prostate cancer (PCa) screening trial. Our trial is the largest component of the European Randomized Study of Screening for Prostate Cancer with more than 80,000 men. Randomly selected deaths in men with PCa (N=442/2568 cases, 17.2%) were reviewed by an independent CoD committee. Median follow-up was 16.8 years in both arms. Overdiagnosis of PCa was present in the SA as the risk ratio for PCa incidence was 1.19 (95% confidence interval (CI) 1.14-1.24). The hazard ratio (HR) for PCa mortality was 0.94 (95%CI 0.82-1.08) in favor of the SA. Agreement with official CoD registry was 94.6% (κ=0.88) in the SA and 95.4% (κ=0.91) in the CA. Altogether 14 PCa deaths were estimated as false-positive in both arms and exclusion of these resulted in HR 0.92 (95% CI 0.80-1.06). A small differential misclassification bias in ascertainment of CoD was present, most likely due to attribution bias (overdiagnosis in the SA). Maximum precision in CoD ascertainment can only be achieved with independent review of all deaths in the diseased population. However, this is cumbersome and expensive and may provide little benefit compared to random sampling. Copyright © 2016 Elsevier Ltd. All rights reserved.
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Alvarez, Pedro M; Beltrán, Fernando J; Rodríguez, Eva M
2005-01-01
Cherry stillage is a high strength organic wastewater arising from the manufacture of alcoholic products by distillation of fermented cherries. It is made up of biorefractory polyphenols in addition to readily biodegradable organic matter. An anaerobic sequencing batch reactor (AnSBR) was used to treat cherry stillage at influent COD ranging from 5 to 50 g/L. Different cycle times were selected to test biomass organic loading rates (OLR(B)), from 0.3 to 1.2 g COD/g VSS.d. COD and TOC efficiency removals higher than 80% were achieved at influent COD up to 28.5 g/L but minimum OLR(B) tested. However, as a result of the temporary inhibition of acetogens and methanogens, volatile fatty acids (VFA) noticeably accumulated and methane production came to a transient standstill when operating at influent COD higher than 10 g/L. At these conditions, the AnSBR showed signs of instability and could not operate efficiently at OLR(B) higher than 0.3 g COD/g VSS.d. A feasible explanation for this inhibition is the presence of toxic polyphenols in cherry stillage. Thus, an ozonation step prior to the AnSBR was observed to be useful, since more than 75% of polyphenols could be removed by ozone. The integrated process was shown to be a suitable treatment technology as the following advantages compared to the single AnSBR treatment were observed: greater polyphenols and color removals, higher COD and TOC removal rates thus enabling the process to effectively operate at higher OLR, higher degree of biomethanation, and good stability with less risk of acidification.
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Meylan, Cesar; McMaster, Travis; Cronin, John; Mohammad, Nur Ikhwan; Rogers, Cailyn; Deklerk, Melissa
2009-07-01
The purposes of this study were to determine the reliability of unilateral vertical, horizontal, and lateral countermovement jump assessments, the interrelationship between these tests, and their usefulness as predictors of sprint (10 m) and change-of-direction (COD) performance for 80 men and women physical education students. Jump performance was assessed on a contact mat and sprint, and COD performances were assessed using timing lights. With regard to the reliability statistics, the largest coefficient of variation (CV) was observed for the vertical jump (CV = 6.7-7.2%) of both genders, whereas the sprint and COD assessments had smallest variability (CV = 0.8 to 2.8%). All intraclass correlation coefficients (ICC) were greater than 0.85, except for the men's COD assessment with the alternate leg. The shared variance between the single-leg vertical, horizontal, and lateral jumps for men and women was less than 50%, indicating that the jumps are relatively independent of one another and represent different leg strength/power qualities. The ability of the jumps to predict sprint and COD performance was limited (R2 < 43%). It would seem that the ability to change direction with 1 leg is relatively independent of a COD with the other leg, especially in the women (R < 30%) of this study. However, if 1 jump assessment were selected to predict sprint and COD performance in a test battery, the single-leg horizontal countermovement jump would seem the logical choice, given the results of this study. Many of the findings in this study have interesting diagnostic and training implications for the strength and conditioning coach.
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NASA Astrophysics Data System (ADS)
Pörtner, H. O.; Berdal, B.; Blust, R.; Brix, O.; Colosimo, A.; De Wachter, B.; Giuliani, A.; Johansen, T.; Fischer, T.; Knust, R.; Lannig, G.; Naevdal, G.; Nedenes, A.; Nyhammer, G.; Sartoris, F. J.; Serendero, I.; Sirabella, P.; Thorkildsen, S.; Zakhartsev, M.
2001-12-01
Effects of global warming on animal distribution and performance become visible in many marine ecosystems. The present study was designed to develop a concept for a cause and effect understanding with respect to temperature changes and to explain ecological findings based on physiological processes. The concept is based on a wide comparison of invertebrate and fish species with a special focus on recent data obtained in two model species of fish. These fish species are both characterized by northern and southern distribution limits in the North Atlantic: eelpout ( Zoarces viviparus), as a typical non-migrating inhabitant of the coastal zone and the cod ( Gadus morhua), as a typical inhabitant of the continental shelf with a high importance for fisheries. Mathematical modelling demonstrates a clear significant correlation between climate induced temperature fluctuations and the recruitment of cod stocks. Growth performance in cod is optimal at temperatures close to 10°C, regardless of the population investigated in a latitudinal cline. However, temperature specific growth rates decrease at higher latitudes. Also, fecundity is less in White Sea than in North and Baltic Sea cod or eelpout populations. These findings suggest that a cold-induced shift in energy budget occurs which is unfavorable for growth performance and fecundity. Thermal tolerance limits shift depending on latitude and are characterized by oxygen limitation at both low or high temperatures. Oxygen supply to tissues is optimized at low temperature by a shift in hemoglobin isoforms and oxygen binding properties to lower affinities and higher unloading potential. Protective stimulation of heat shock protein synthesis was not observed. According to a recent model of thermal tolerance the downward shift of tolerance limits during cold adaptation is associated with rising mitochondrial densities and, thus, aerobic capacity and performance in the cold, especially in eurythermal species. At the same time the costs of mitochondrial maintenance reflected by mitochondrial proton leakage should rise leaving a lower energy fraction for growth and reproduction. The preliminary conclusion can be drawn that warming will cause a northern shift of distribution limits for both species with a rise in growth performance and fecundity larger than expected from the Q 10 effect in the north and lower growth or even extinction of the species in the south. Such a shift may heavily affect fishing activities in the North Sea.
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Reubens, Jan T; Pasotti, Francesca; Degraer, Steven; Vincx, Magda
2013-09-01
Because offshore wind energy development is fast growing in Europe it is important to investigate the changes in the marine environment and how these may influence local biodiversity and ecosystem functioning. One of the species affected by these ecosystem changes is Atlantic cod (Gadus morhua), a heavily exploited, commercially important fish species. In this research we investigated the residency, site fidelity and habitat use of Atlantic cod on a temporal scale at windmill artificial reefs in the Belgian part of the North Sea. Acoustic telemetry was used and the Vemco VR2W position system was deployed to quantify the movement behaviour. In total, 22 Atlantic cod were tagged and monitored for up to one year. Many fish were present near the artificial reefs during summer and autumn, and demonstrated strong residency and high individual detection rates. When present within the study area, Atlantic cod also showed distinct habitat selectivity. We identified aggregation near the artificial hard substrates of the wind turbines. In addition, a clear seasonal pattern in presence was observed. The high number of fish present in summer and autumn alternated with a period of very low densities during the winter period. Copyright © 2013 Elsevier Ltd. All rights reserved.
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Asadi, Abbas; Arazi, Hamid; Ramirez-Campillo, Rodrigo; Moran, Jason; Izquierdo, Mikel
2017-09-01
Asadi, A, Arazi, H, Ramirez-Campillo, R, Moran, J, and Izquierdo, M. Influence of maturation stage on agility performance gains after plyometric training: a systematic review and meta-analysis. J Strength Cond Res 31(9): 2609-2617, 2017-Although plyometric training (PT) improves change of direction (COD) ability, the influence of age on COD gains after PT is unclear. Therefore, the aim of this systematic review was to identify the age-related pattern of improvement in COD ability after PT in youths. A computerized search within 6 databases was performed, selecting studies based on specific inclusion criteria: experimental trials published in English-language journals, PT focused on the lower-body, COD ability measurements reported before and after training, and male participants aged 10 to 18 years. Sixteen articles with a total of 30 effect sizes (ESs) in the experimental groups and 13 ESs in the control groups were included. For the analyses, subjects were categorized into 3 age groups: 10-12.9 years of age (PRE), 13-15.9 years of age (MID), and 16-18 years of age (POST). Independent of age, PT improved COD ability in youths (ES = 0.86, time gains [TG = -0.61]). However, a tendency toward greater COD ability gains was observed in older subjects (MID, ES = 0.95; POST, ES = 0.99) compared with younger subjects (PRE, ES = 0.68). Pearson product-moment correlation (r) indicated that 2-weekly sessions of PT-induced meaningful COD ability gains (for ES, r = 0.436; for TG, r = -0.624). A positive relationship was found between training intensity and ES (r = 0.493). In conclusion, PT improves COD ability in youths, with meaningfully greater effects in older youths. Two PT sessions per week, with 1,400 moderate-intensity jumps for 7 weeks, seems to be an adequate dose.
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Diaz Pauli, B; Wiech, M; Heino, M; Utne-Palm, A C
2015-03-01
This study assessed whether fishing gear was selective on behavioural traits, such as boldness and activity, and how this was related with a productivity trait, growth. Female guppies Poecilia reticulata were screened for their behaviour on the shy-bold axis and activity, and then tested whether they were captured differently by passive and active fishing gear, here represented by a trap and a trawl. Both gears were selective on boldness; bold individuals were caught faster by the trap, but escaped the trawl more often. Boldness and gear vulnerability showed weak correlations with activity and growth. The results draw attention to the importance of the behavioural dimension of fishing: selective fishing on behavioural traits will change the trait composition of the population, and might eventually affect resilience and fishery productivity. © 2015 The Fisheries Society of the British Isles.
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Ozonation of Common Textile Auxiliaries
NASA Astrophysics Data System (ADS)
Iskender, Gulen; Arslan-Alaton, Idil; Koyunluoglu, Sebnem; Yilmaz, Zeynep; Germirli Babuna, Fatos
2016-10-01
The treatability of four different commonly applied textile auxiliary chemicals, namely two tannin formulations (Tannin 1: a condensation product of aryl sulphonate; Tannin 2: natural tannic acid) and two biocidal finishing agents (Biocide 1: 2,4,4’-trichloro-2’- hydroxydiphenyl ether; Biocide 2: a nonionic diphenyl alkane derivative) with ozone was investigated. Increasing the ozone dose yielded higher COD removals for the natural tannin. Optimum ozone doses of 485 and 662 mg/h were obtained at a pH of 3.5 for natural and synthetic tannin carrying textile bath discharges, respectively. When the reaction pH was increased from 3.5 to 7.0, a slight decrease in COD removal was observed for the natural tannin due to ozone selectivity towards its polyaromatic structure. The same increase in ozonation pH enhanced COD removals for the synthetic tannin as a result of enhanced ozone decomposition rendering free radical chain reactions dominant. Optimum ozone doses of 499 and 563 mg/h were established for Biocide 1 and 2, respectively. With the increase of ozonation, pH exhibited a positive influence on COD removals for both textile tannins. A substantial improvement in terms of TOC removals was observed as the reaction pH was increased from 3.5 to 7.0 for the synthetic tannin, and from 7 to 12 for both textile biocides. Higher AOX removals were evident at pH 7 than at pH 12 for Biocide 1 as a result of the higher selectivity of the dehalogenation reaction at neutral pH.
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Din, M F M; Ujang, Z; van Loosdrecht, M C M; Ahmad, A; Sairan, M F
2006-01-01
The process for the production of biodegradable plastic material (polyhydroxyalkanoates, PHAs) from microbial cells by mixed-bacterial cultivation using readily available waste (renewable resources) is the main consideration nowadays. These observations have shown impressive results typically under high carbon fraction, COD/N and COD/P (usually described as nutrient-limiting conditions) and warmest temperature (moderate condition). Therefore, the aim of this work is predominantly to select mixed cultures under high storage responded by cultivation on a substrate - non limited in a single batch reactor with shortest period for feeding and to characterize their storage response by using specific and kinetics determination. In that case, the selected-fixed temperature is 30 degrees C to establish tropical conditions. During the accumulated steady-state period, the cell growth was inhibited by high PHA content within the cells because of the carbon reserve consumption. From the experiments, there is no doubt about the PHA accumulation even at high carbon fraction ratio. Apparently, the best accumulation occurred at carbon fraction, 160 +/- 7.97 g COD/g N (PHAmean, = 44.54% of dried cells). Unfortunately, the highest PHA productivity was achieved at the high carbon fraction, 560 +/- 1.62 g COD/g N (0.152 +/- 0.17 g/l. min). Overall results showed that with high carbon fraction induced to the cultivation, the PO4 and NO3 can remove up to 20% in single cultivation.
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Al-Shiekh Khalil, Wael; Shanableh, Abdullah; Rigby, Portia; Kokot, Serge
2005-04-01
The effectiveness of hydrothermal treatment for the destruction of the organic content of sludge waste was investigated. The sludge sampled in this study contained approximately 2% solids. The experimental program consisted of hydrothermal treatment experiments conducted in a batch reactor at temperatures between 100 and 250 degrees C, with the addition of an oxidant (hydrogen peroxide) in the range of 0-150% with reference to TCOD, and reaction times of up to 60 min. The results suggested that the availability of oxidant, reaction temperature and reaction time were the determining factors for COD removal. A significant fraction of the COD remaining after treatment consisted of the dissolved COD. The results confirmed that hydrothermal treatment proceeds through hydrolysis resulting in the production of dissolved organic products followed by COD removal through oxidation. Two MCDM chemometrics methods, PROMETHEE and GAIA, were applied to process the large data matrix so as to facilitate the selection of the most suitable hydrothermal conditions for sludge destruction. Two possible scenarios were produced from this analysis-one depended on the use of high temperatures and no oxidant, while the second offered a choice of compromise solutions at lower temperatures but with the use of at least some oxidant. Thus, for the final choice of operating conditions, the decision maker needs local knowledge of the costs and available infrastructure. In principle, such information could be added as further criteria to the data matrix and new rankings obtained.
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Carlson, Carl S.; Masterson, John P.; Walter, Donald A.; Barbaro, Jeffrey R.
2017-12-21
IntroductionThe U.S. Geological Survey (USGS), in support of the Massachusetts Estuaries Project (MEP), delineated groundwater-contributing areas to various hydrologic receptors including ponds, streams, and coastal water bodies throughout southeastern Massachusetts, including portions of the Plymouth-Carver aquifer system and all of Cape Cod. These contributing areas were delineated over a 6-year period from 2003 through 2008 by using previously published regional USGS groundwater-flow models for the Plymouth-Carver region (Masterson and others, 2009), the Sagamore (western) and Monomoy (eastern) flow lenses of Cape Cod (Walter and Whealan, 2005), and lower Cape Cod (Masterson, 2004). The original USGS groundwater-contributing areas were subsequently revised in some locations by the MEP to remove modeling artifacts or to make the contributing areas more consistent with site-specific hydrologic conditions without further USGS review. This report describes the process used to create the USGS groundwater-contributing areas and provides these model results in their original format in a single, publicly accessible publication.
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Mohamed, Mona A; El-Gendy, Dalia M; Ahmed, Nashaat; Banks, Craig E; Allam, Nageh K
2018-03-15
Adenine-functionalized spongy graphene (FSG) composite, fabricated via a facile and green synthetic method, has been explored as a potential electrocatalyst toward the electroanalytical sensing of codeine phosphate (COD). The synthesized composite is characterized using Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, X-ray powder diffraction, UV-vis absorption spectroscopy, scanning electron microscopy, high resolution transmission electron microscopy (HRTEM), and thermogravimetric analysis. The FSG was electrically wired via modification upon screen-printed (macro electrode) sensors, which behave as a hybrid electrode material for the sensitive and selective codeine phosphate (COD) determination in the presence of paracetamol (PAR) and caffeine (CAF). The FSG- modified sensor showed an excellent electrocatalytic response towards the sensing of COD with a wide linear response range of 2.0 × 10 -8 -2.0 × 10 -4 M and a detection limit (LOD) of 5.8 × 10 -9 M, indicating its potential for the sensing of COD in clinical samples and pharmaceutical formulations. Copyright © 2017 Elsevier B.V. All rights reserved.
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Indiscriminate Fisheries: Understanding the Foodweb of the Great Tonle Sap Lake, Cambodia
NASA Astrophysics Data System (ADS)
Hannah, L.; Kaufman, L.
2014-12-01
Indiscriminate fisheries target multiple species with multiple gear types. In contrast to well-studied, industrialized single-species, single-gear fisheries, little theory and little but growing literature on practice exists for indiscriminate fisheries. Indiscriminate fisheries are disproportionately important in low-income countries, providing most of the animal protein intake in countries such as Cambodia and Bangladesh. Indiscriminate fisheries may be either freshwater or marine, but here we focus on what may be the largest freshwater indiscriminate fishery in the world. Cambodia's freshwater fishery stands out because it provides the majority of animal protein to over 3 million people living in poverty. The fishery of the Tonle Sap lake is one of the largest, if not the largest contributor to this freshwater fish take, and is perhaps the largest freshwater fishery in the world. In contrast to its importance, very little is known about the foodweb ecology of this system, or how community management which now governs the entire fishery, interacts with biological and physical factors such as climate change.The foodweb of the Tonle Sap has changed dramatically due to high fishing pressure. A system that once harbored giant catfish, barbs and stingrays is now dominated by fish under 20cm in length. The simplification of the system may not have reduced its productivity. Theory of indiscriminate fisheries suggests that r-selected species may be favored and that biomass available for harvest may be maximized, while being more sensitive to environmental fluctuations such as climate change due to food web simplification. The r-selection and size predictions of theory have been confirmed by observations of the Tonle Sap. Early model results suggest sensitivity to environmental stochasticity. The interaction of these ecological changes with social systems will be tested in the Tonle Sap. Fisheries management across the lake has been transferred to community management units. The capacity of the community management units to control illegal activities or set economically beneficial management objectives is unknown. Our social survey suggests that strengthening community management units could have strong benefits for incomes and biodiversity on the lake.
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Federal Register 2010, 2011, 2012, 2013, 2014
2011-10-03
...The Law Enforcement Advisory Panel (LEAP) will meet via conference call on October 20, 2011 to select nominees for a Law Enforcement Office of the Year (LEOY) Award. The Council will meet via conference call on November 2, 2011 to review the LEAP's recommendations and select a deserving law enforcement officer to receive the award. See SUPPLEMENTARY INFORMATION.
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NASA Astrophysics Data System (ADS)
Vanyushin, George; Bulatova, Tatiana; Klochkov, Dmitriy; Troshkov, Anatoliy; Kruzhalov, Michail
2013-04-01
In this study, the attempt to consider the relationship between sea surface anomalies of temperature (SST anomalies °C) in spawning area of the Norwegian Arctic cod off the Lofoten islands in coastal zone of the Norwegian Sea and modern cod total stock biomass including forecasting assessment of future cod generation success. Continuous long-term database of the sea surface temperature (SST) was created on the NOAA satellites data. Mean monthly SST and SST anomalies are computed for the selected area on the basis of the weekly SST maps for the period of 1998-2012. These maps were plotted with the satellite SST data, as well as information of vessels, byoies and coastal stations. All data were classified by spawning seasons (March-April) and years. The results indicate that poor and low middle generations of cod (2001, 2006, 2007) occurred in years with negative or extremely high positive anomalies in the spawning area. The SST anomalies in years which were close to normal or some more normal significances provide conditions for appearance strong or very strong generations of cod (1998, 2000, 2002, 2004, 2005, 2006, 2008, 2009). Temperature conditions in concrete years influence on different indexes of cod directly. So, the mean temperature in spawning seasons in years 1999-2005 was ≈5,0°C and SST anomaly - +0,35°C, by the way average year significances indexes of cod were: total stock biomass - 1425,0 th.t., total spawning biomass - 460,0 th.t., recruitment (age 3+) - 535,0 mln. units and landings - 530,0 th.t. In spawning seasons 2006-2012 years the average data were following: mean SST ≈6,0°C, SST anomaly - +1,29°C, total stock biomass - 2185,0 th.t., total spawning biomass - 1211,0 th.t., recruitment (age 3+) - 821,0 mln. units and landings - 600,0 th.t. The SST and SST anomalies (the NOAA satellite data) characterize increase of decrease in input of warm Atlantic waters which form numerous eddies along the flows of the main warm currents thus creating favorable conditions for development of the cod larvae and fry and provide them with food stock, finally, direct influence on forming total stock biomass of cod and helping its population forecast. Key words: satellite monitoring of SST, Northeast Arctic cod, spawning area, maps of SST, prognosis.
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NASA Astrophysics Data System (ADS)
Runge, Jeffrey A.; Kovach, Adrienne I.; Churchill, James H.; Kerr, Lisa A.; Morrison, John R.; Beardsley, Robert C.; Berlinsky, David L.; Chen, Changsheng; Cadrin, Steven X.; Davis, Cabell S.; Ford, Kathryn H.; Grabowski, Jonathan H.; Howell, W. Huntting; Ji, Rubao; Jones, Rebecca J.; Pershing, Andrew J.; Record, Nicholas R.; Thomas, Andrew C.; Sherwood, Graham D.; Tallack, Shelly M. L.; Townsend, David W.
2010-10-01
We put forward a combined observing and modeling strategy for evaluating effects of environmental forcing on the dynamics of spatially structured cod populations spawning in the western Gulf of Maine. Recent work indicates at least two genetically differentiated complexes in this region: a late spring spawning, coastal population centered in Ipswich Bay, and a population that spawns in winter inshore and on nearshore banks in the Gulf of Maine and off southern New England. The two populations likely differ in trophic interactions and in physiological and behavioral responses to different winter and spring environments. Coupled physical-biological modeling has advanced to the point where within-decade forecasting of environmental conditions for recruitment to each of the two populations is feasible. However, the modeling needs to be supported by hydrographic, primary production and zooplankton data collected by buoys, and by data from remote sensing and fixed station sampling. Forecasts of environmentally driven dispersal and growth of planktonic early life stages, combined with an understanding of possible population-specific predator fields, usage of coastal habitat by juveniles and adult resident and migratory patterns, can be used to develop scenarios for spatially explicit population responses to multiple forcings, including climate change, anthropogenic impacts on nearshore juvenile habitat, connectivity among populations and management interventions such as regional fisheries closures.
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Kuuliala, L; Al Hage, Y; Ioannidis, A-G; Sader, M; Kerckhof, F-M; Vanderroost, M; Boon, N; De Baets, B; De Meulenaer, B; Ragaert, P; Devlieghere, F
2018-04-01
During fish spoilage, microbial metabolism leads to the production of volatile organic compounds (VOCs), characteristic off-odors and eventual consumer rejection. The aim of the present study was to contribute to the development of intelligent packaging technologies by identifying and quantifying VOCs that indicate spoilage of raw Atlantic cod (Gadus morhua) under atmospheres (%v/v CO 2 /O 2 /N 2 ) 60/40/0, 60/5/35 and air. Spoilage was examined by microbiological, chemical and sensory analyses over storage time at 4 or 8 °C. Selected-ion flow-tube mass spectrometry (SIFT-MS) was used for quantifying selected VOCs and amplicon sequencing of the 16S rRNA gene was used for the characterization of the cod microbiota. OTUs classified within the Photobacterium genus increased in relative abundance over time under all storage conditions, suggesting that Photobacterium contributed to spoilage and VOC production. The onset of exponential VOC concentration increase and sensory rejection occurred at high total plate counts (7-7.5 log). Monitoring of early spoilage thus calls for sensitivity for low VOC concentrations. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Ghosh, Ruma; Lokman, P Mark; Lamare, Miles D; Metcalf, Victoria J; Burritt, David J; Davison, William; Hageman, Kimberly J
2013-03-15
Although polybrominated diphenyl ethers (PBDEs) have the ability to undergo long-range atmospheric transport to remote ecosystems like Antarctica, a recent study found evidence for a local source within the Antarctic. PBDEs from sewage treatment outfalls of McMurdo Station and Scott Base on Ross Island have been attributed to the high concentrations measured in emerald rock cod (Trematomus bernacchii). The potential impact of PBDEs on Antarctic fish physiology is unknown and therefore, the aim of this study was to obtain a greater understanding of physiological responses of emerald rock cod for assessing changes in ecosystem quality. A PBDE mixture (ΣPBDE 8 congeners) was administered fortnightly over 42 days and physiological changes were observed throughout this period and for a further 14 days thereafter. Changes in liver composition, molecular level changes and enzyme activities of selected detoxification-mediated and antioxidant defence markers were measured. Changes in total lipid, lipid peroxide and protein carbonyl concentrations in emerald rock cod liver were consistent with increases in nucleus surface area in the PBDE-treated groups, suggesting alterations in cellular function. Changes in the activities of selected antioxidant enzymes indirectly indicated oxidative stress, possibly resulting in the changes in liver composition. Additionally, glutathione-S-transferase (GST) activity reached its peak faster than that of ethoxyresorufin-O-deethylase (EROD), suggesting that during the early response to PBDE exposures there could be a greater involvement of GST-mediated detoxification. Thus, for at least the species examined here, protein carbonyl and lipid peroxides were useful and informative biomarkers for cellular level responses following PBDE-related exposure. Furthermore, our findings suggest that emerald rock cod exposed to PBDEs develop oxidative stress - a condition with potential consequences for fish growth, health and reproduction. Copyright © 2012 Elsevier B.V. All rights reserved.
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Sobecka, E; Szostakowska, B; MacKenzie, K; Hemmingsen, W; Prajsnar, S; Eydal, M
2012-03-01
Previous studies have shown considerable variability in morphological features and the existence of genetically distinct sibling species in the acanthocephalan Echinorhynchus gadi Zoega in Müller, 1776. The aim of the present study was to follow up and extend those earlier studies by using a combination of DNA analysis and morphometrics to investigate differences between samples of E. gadi from Atlantic cod Gadus morhua L. caught at five fishing grounds in the Baltic Sea and three in different parts of the North Atlantic. Twelve morphological features were measured in 431 specimens of E. gadi, 99 individuals were studied by polymerase chain reaction-restriction fragment length polymorphosm (PCR-RFLP), and selected PCR products were sequenced. The molecular analyses showed the nucleotide sequences of E. gadi rDNA from cod caught at all the sampling sites to be identical. The comparative morphological study, in contrast, revealed significant differences between samples of E. gadi from different sampling sites and showed the separation of E. gadi into two groups corresponding approximately to the systematic classification of cod into the two subspecies, Atlantic G. morhua morhua and Baltic G. morhua callarias. The E. gadi infrapopulation size had a significant effect on some of the morphological features. The results are discussed in relation to cod population biology, the hydrography of the study area and the history of the Baltic Sea formation.
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Tertiary treatment of landfill leachates by adsorption.
Marañón, Elena; Castrillón, Leonor; Fernández-Nava, Yoland; Fernández-Méndez, Alejandro; Fernández-Sánchez, Arcadio
2009-08-01
The leachates produced at the municipal solid waste (MSW) landfill of Asturias (Spain) were submitted to a biological treatment consisting of a pressurized nitrification-denitrification process followed by ultrafiltration. The effluent from this treatment plant has a high chemical oxygen demand : biochemical oxygen demand (COD : BOD( 5)) ratio (about 25 : 1). The COD values of the effluent are above the discharge limits permitted by current legislation and therefore require a final treatment. In the present study, adsorption was investigated as a possible post-treatment. Three activated carbons (Organosorb 10, Organosorb 10MB and Filtracarb CC65/1240) were selected and equilibrium and column data were obtained. The best results were obtained with Organosorb 10MB, although adsorption capacities obtained were low and equilibrium was unfavourable. Adsorption capacities ranged between 150 and 157 mg COD g(-1) for an activated carbon dosage of 1 mg L(-1) and between 13.3 and 18.4 mg COD g(-1) for a dosage of 20 mg L(-1). As regards colour, adsorption capacities ranged between 145 and 175 UPtCo g(-1) for the lower dosage and between 16 and 29 UPtCo g(-1) for the higher dosage. Removal efficiency increased with the dosage of activated carbon employed, obtaining maximum COD and colour removals of 63 and 45%, respectively, for a dosage of 20 mg L(-1) after 5 h contact time.
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Olsvik, Pål A; Berntssen, Marc H G; Hylland, Ketil; Eriksen, Dag Ø; Holen, Elisabeth
2012-07-01
The aim of this study was to investigate whether (226)Ra, a radionuclide present in produced water from oil platforms in the North Sea and other offshore drilling areas, could affect vulnerable early life stages of Atlantic cod (Gadus morhua). Blastula-stage embryonic cells (EC) from fertilized eggs of Atlantic cod were isolated and exposed to environmental relevant concentrations of (226)Ra and transcription of selected genes quantified. The results showed a weak, but significant up-regulation of GPx3 and HSP70 transcripts after 48 h of exposure to 2.11 Bq/L. In EC exposed to three (226)Ra concentrations (2.11, 23 and 117 Bq/L) for 12 h, metallothionein, HSP90AA, thioredoxin and caspase 8 were significantly up-regulated in cells exposed to 117 Bq/L, whereas thioredoxin was also significantly up-regulated in EC exposed to 23 Bq/L. When EC were exposed to the same (226)Ra concentrations for 48 h, only heme oxygenase was significantly up-regulated in the 23 Bq/L exposure group. The results suggest that environmentally relevant activities of (226)Ra may induce oxidative stress and apoptosis in fish ECs. Exposure of Atlantic cod EC to Cd, selected as a model toxicant, supported the ability of EC around blastula stage to respond to toxicants by altered transcription. Due to dilution, environmentally relevant concentrations of radionuclides present in produced water would be expected to pose a minor threat to early life stages of fish. Copyright © 2012 Elsevier Ltd. All rights reserved.
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Federal Register 2010, 2011, 2012, 2013, 2014
2013-01-02
...This action proposes revisions to several portions of the Pacific Coast Groundfish Fishery Trawl Rationalization Program regulations and requests comments on NMFS' preliminary conclusion that the Pacific Fishery Management Council's (Council's) selection of the no action alternative regarding the reconsideration of initial allocation of Pacific whiting (whiting) is consistent with the Magnuson-Stevens Fishery Conservation and Management Act (MSA), the Pacific Coast Groundfish Fishery Management Plan (FMP), and other applicable law.. This action is necessary to comply with a court order requiring NMFS to reconsider the initial allocation of whiting to the shorebased individual fishing quota (IFQ) fishery and the at-sea mothership fishery. These proposed regulatory changes would affect the transfer of quota share (QS) and individual bycatch quota (IBQ) between QS accounts in the shorebased IFQ fishery, and severability of catch history assignments in the mothership fishery, both of which would be allowed on specified dates with the exception of widow rockfish. Widow rockfish is no longer an overfished species and transfer of QS for this species will be reinstated pending reconsideration of the allocation of widow rockfish QS in a future action. The divestiture period for widow rockfish QS in the IFQ fishery is also proposed to be delayed indefinitely.
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Thurstan, Ruth H.; Roberts, Callum M.
2010-01-01
Background The Firth of Clyde is a large inlet of the sea that extends over 100 km into Scotland's west coast. Methods We compiled detailed fisheries landings data for this area and combined them with historical accounts to build a picture of change due to fishing activity over the last 200 years. Findings In the early 19th century, prior to the onset of industrial fishing, the Firth of Clyde supported diverse and productive fisheries for species such as herring (Clupea harengus, Clupeidae), cod (Gadus morhua, Gadidae), haddock (Melanogrammus aeglefinus, Gadidae), turbot (Psetta maxima, Scophthalmidae) and flounder (Platichthys flesus, Pleuronectidae). The 19th century saw increased demand for fish, which encouraged more indiscriminate methods of fishing such as bottom trawling. During the 1880s, fish landings began to decline, and upon the recommendation of local fishers and scientists, the Firth of Clyde was closed to large trawling vessels in 1889. This closure remained in place until 1962 when bottom trawling for Norway lobster (Nephrops norvegicus, Nephropidae) was approved in areas more than three nautical miles from the coast. During the 1960s and 1970s, landings of bottomfish increased as trawling intensified. The trawl closure within three nautical miles of the coast was repealed in 1984 under pressure from the industry. Thereafter, bottomfish landings went into terminal decline, with all species collapsing to zero or near zero landings by the early 21st century. Herring fisheries collapsed in the 1970s as more efficient mid-water trawls and fish finders were introduced, while a fishery for mid-water saithe (Pollachius virens, Gadidae) underwent a boom and bust shortly after discovery in the late 1960s. The only commercial fisheries that remain today are for Nephrops and scallops (Pecten maximus, Pectinidae). Significance The Firth of Clyde is a marine ecosystem nearing the endpoint of overfishing, a time when no species remain that are capable of sustaining commercial catches. The evidence suggests that trawl closures helped maintain productive fisheries through the mid-20th century, and their reopening precipitated collapse of bottomfish stocks. We argue that continued intensive bottom trawling for Nephrops with fine mesh nets will prevent the recovery of other species. This once diverse and highly productive environment will only be restored if trawl closures or other protected areas are re-introduced. The Firth of Clyde represents at a small scale a process that is occurring ocean-wide today, and its experience serves as a warning to others. PMID:20686614
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ENSO events in the northern Gulf of Alaska, and effects on selected marine fisheries
Bailey, K.M.; Macklin, S.A.; Reed, R.K.; Brodeur, R.D.; Ingraham, W.J.; Piatt, John F.; Shima, M.; Francis, R.C.; Anderson, P.J.; Royer, T.C.; Hollowed, A.; Somerton, D.A.; Wooster, W.S.
1995-01-01
The 1991-93 El Nino-Southern Oscillation (ENSO) event first appeared in the northern Gulf of Alaska in autumn 1991 with warm sea-surface temperatures. In winter 1992, there were pulses of increased sea level and anomalous circulation. El Nino conditions persisted at least through summer 1993. The effects of this ENSO event on major groundfish species and Pacific herring in the northern Gulf of Alaska were examined and compared with the effects of previous ENSO events. There is little evidence that the 1991-93 or 1982-83 ENSO events affected landings of walleye pollock, Pacific cod, Pacific halibut, or arrowtooth flounder. Some changes in distribution of groundfish species were observed in 1993, but the effect was similar to changes observed in non-ENSO warm years. In general, warm ocean conditions have a positive effect on recruitment of northern stocks, but ENSO events appear to have an inconsistent effect on year-class strength within species and among different species. For example, strong year classes of halibut and arrowtooth flounder sometimes, but not always, coincide with ENSO events; ENSO events are associated with moderate to weak year classes of cod and pollock. However, post-ENSO warm years often are associated with strong recruitment of many groundfish species. Major changes have occurred in the Gulf of Alaska ecosystem since 1977. The influence of the 1976 ENSO event in precipitating these changes and the role of the frequency or strength of subsequent El Nino events is presently unknown. Herring and other stocks of small pelagic fishes may be more affected by ENSO events. In particular, decreased catches, recruitment, and weight-at-age of herring are sometimes associated with ENSO events. Furthermore, a variety of seabirds which feed mostly on pelagic forage fishes or the pelagic juvenile stages of groundfish suffered widespread mortalities and breeding failures in the Gulf of Alaska during the ENSO years of 1983 and 1993. These effects on seabirds were also observed over a wider geographic range, from California to the western Bering Sea.
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Vestrum, Ragnhild I; Attramadal, Kari J K; Winge, Per; Li, Keshuai; Olsen, Yngvar; Bones, Atle M; Vadstein, Olav; Bakke, Ingrid
2018-01-01
We have previously shown that K-selection and microbial stability in the rearing water increases survival and growth of Atlantic cod ( Gadus morhua ) larvae, and that recirculating aquaculture systems (RAS) are compatible with this. Here, we have assessed how water treatment influenced the larval microbiota and host responses at the gene expression level. Cod larvae were reared with two different rearing water systems: a RAS and a flow-through system (FTS). The water microbiota was examined using a 16S rDNA PCR/DGGE strategy. RNA extracted from larvae at 8, 13, and 17 days post hatching was used for microbiota and microarray gene expression analysis. Bacterial cDNA was synthesized and used for 16S rRNA amplicon 454 pyrosequencing of larval microbiota. Both water and larval microbiota differed significantly between the systems, and the larval microbiota appeared to become more dissimilar between systems with time. In total 4 phyla were identified for all larvae: Actinobacteria, Bacteroidetes, Firmicutes, and Proteobacteria. The most profound difference in larval microbiota was a high abundance of Arcobacter (Epsilonproteobacteria) in FTS larvae (34 ± 9% of total reads). Arcobacter includes several species that are known pathogens for humans and animals. Cod larval transcriptome responses were investigated using an oligonucleotide gene expression microarray covering approximately 24,000 genes. Interestingly, FTS larvae transcriptional profiles revealed an overrepresentation of upregulated transcripts associated with responses to pathogens and infections, such as c1ql3-like , pglyrp-2-like and zg16, compared to RAS larvae. In conclusion, distinct water treatment systems induced differences in the larval microbiota. FTS larvae showed up-regulation of transcripts associated with responses to microbial stress. These results are consistent with the hypothesis that RAS promotes K-selection and microbial stability by maintaining a microbial load close to the carrying capacity of the system, and ensuring long retention times for both bacteria and water in the system.
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Vestrum, Ragnhild I.; Attramadal, Kari J. K.; Winge, Per; Li, Keshuai; Olsen, Yngvar; Bones, Atle M.; Vadstein, Olav; Bakke, Ingrid
2018-01-01
We have previously shown that K-selection and microbial stability in the rearing water increases survival and growth of Atlantic cod (Gadus morhua) larvae, and that recirculating aquaculture systems (RAS) are compatible with this. Here, we have assessed how water treatment influenced the larval microbiota and host responses at the gene expression level. Cod larvae were reared with two different rearing water systems: a RAS and a flow-through system (FTS). The water microbiota was examined using a 16S rDNA PCR/DGGE strategy. RNA extracted from larvae at 8, 13, and 17 days post hatching was used for microbiota and microarray gene expression analysis. Bacterial cDNA was synthesized and used for 16S rRNA amplicon 454 pyrosequencing of larval microbiota. Both water and larval microbiota differed significantly between the systems, and the larval microbiota appeared to become more dissimilar between systems with time. In total 4 phyla were identified for all larvae: Actinobacteria, Bacteroidetes, Firmicutes, and Proteobacteria. The most profound difference in larval microbiota was a high abundance of Arcobacter (Epsilonproteobacteria) in FTS larvae (34 ± 9% of total reads). Arcobacter includes several species that are known pathogens for humans and animals. Cod larval transcriptome responses were investigated using an oligonucleotide gene expression microarray covering approximately 24,000 genes. Interestingly, FTS larvae transcriptional profiles revealed an overrepresentation of upregulated transcripts associated with responses to pathogens and infections, such as c1ql3-like, pglyrp-2-like and zg16, compared to RAS larvae. In conclusion, distinct water treatment systems induced differences in the larval microbiota. FTS larvae showed up-regulation of transcripts associated with responses to microbial stress. These results are consistent with the hypothesis that RAS promotes K-selection and microbial stability by maintaining a microbial load close to the carrying capacity of the system, and ensuring long retention times for both bacteria and water in the system. PMID:29765364
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Pereira, Lucas A; Nimphius, Sophia; Kobal, Ronaldo; Kitamura, Katia; Turisco, Luiz A L; Orsi, Rita C; Cal Abad, César Cs; Loturco, Irineu
2018-02-22
The aims of this study were to (1) assess the relationship between selected speed-power related abilities (determined by 20-m sprint, unloaded countermovement and squat jumps [CMJ and SJ] and loaded jump squat [JS]) and performance in two distinct change of direction (COD) protocols (Zigzag and T-Test), and (2) determine the magnitude of difference between female and male Brazilian National Olympic Team handball athletes. Fifteen male and twenty-three female elite handball athletes volunteered to perform the following assessments: SJ and CMJ; Zigzag and T-Test; 20-m sprint with 5-, 10-, and 20-m splits, and mean propulsive power (MPP) in JS. Pearson product moment correlation (P< 0.05) was performed to determine the relationship between the COD tests (Zigzag and T-test) and speed-power measures (sprint, SJ, CMJ and JS). The differences between male and female performances were determined using the magnitude-based inference. Moderate to very large significant correlations were observed between both COD tests and the speed-power abilities. Further, male athletes demonstrated likely to almost certainly higher performances than female athletes in all assessed variables. The results of the current study suggest that different speed-power qualities are strongly correlated to the performance obtained in various COD assessments (r values varying from 0.38 to 0.84 and from 0.34 to 0.84 for correlations between speed and power tests with Zigzag and T-Test, respectively). However, the level of these associations can vary greatly, according to the mechanical demands of each respective COD task. Whilst COD tests may be difficult to implement during competitive seasons, due to the strong correlations presented herein, the regular use of vertical jump tests with these athletes seems to be an effective and applied alternative. Furthermore, it might be inferred that the proper development of loaded and unloaded jump abilities has potential for improving the physical qualities related to COD performance in handball athletes.
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NASA Astrophysics Data System (ADS)
Kim, Yumi; Kim, Sang-Woo; Kim, Man-Hae; Yoon, Soon-Chang
2014-03-01
This study examines cirrus cloud top and bottom heights (CTH and CBH, respectively) and the associated optical properties revealed by ground-based lidar in Seoul (SNU-L), Korea, and space-borne Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP), which were obtained during a three-year measurement period between July 2006 and June 2009. From two selected cases, we determined good agreement in CTH and CBH with cirrus cloud optical depth (COD) between ground-based lidar and space-borne CALIOP. In particular, CODs at a wavelength of 532 nm calculated from the three years of SNU-L and CALIOP measurements were 0.417 ± 0.394 and 0.425 ± 0.479, respectively. The fraction of COD lower than 0.1 was approximately 17% and 25% of the total SNU-L and CALIOP profiles, respectively, and approximately 50% of both lidar profiles were classified as sub-visual or optically thin such that COD was < 0.3. The mean depolarization ratio was estimated to be 0.30 ± 0.06 for SNU-L and 0.34 ± 0.08 for CALIOP. The monthly variation of CODs from SNU-L and CALIOP measurements was not distinct, whereas cirrus altitudes from both SNU-L and CALIOP showed distinct monthly variation. CALIOP observations showed that cirrus clouds reached the tropopause level in all months, whereas the up-looking SNU-L did not detect cirrus clouds near the tropopause in summer due to signal attenuation by underlying optically thick clouds. The cloud layer thickness (CLT) and COD showed a distinct linear relationship up to approximately 2 km of the CLT; however, the COD did not increase, but remained constant when the CLT was greater than 2.0 km. The ice crystal content, lidar signal attenuation, and the presence of multi-layered cirrus clouds may have contributed to this tendency.
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Fast and behavior-selective exploitation of a marine fish targeted by anglers
Alós, Josep; Palmer, Miquel; Rosselló, Rosario; Arlinghaus, Robert
2016-01-01
Harvesting of wild-living animals is often intensive and may selectively target heritable behavioral traits. We studied the exploitation dynamics and the vulnerability consequences of individual heterogeneity in movement-related behaviors in free-ranging pearly razorfish (Xyrichthys novacula). Using underwater-video recording, we firstly document a fast and high exploitation rate of about 60% of the adult population removed in just few days after the opening of the season. Subsequently, we tagged a sample of individuals with acoustic transmitters and studied whether behavioral traits were significant predictors of the vulnerability to angling. Tagged individuals revealed repeatable behaviors in several home range-related traits, suggesting the presence of spatial behavioral types. The individuals surviving the experimental fishery showed only localized and low-intensity movement patterns. Our study provides new insights for understanding the harvesting pressures and selective properties acting on behavioral traits of recreational fishing. Many fish stocks around the globe are today predominantly exploited by recreational fisheries. The fisheries-induced change in fish behavior described here may be therefore widespread, and has the potential to alter food-webs, profitability of the fisheries and to affect stock assessment by eroding catchability in the long-term. PMID:27922022
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Asis, Angelli Marie Jacynth M; Destura, Irma; Santos, Mudjekeewis D
2016-05-01
Milkfish fry fishery, an important industry in the Philippines, uses non-selective fishing gears and push nets in coastal areas which lead to the capture of other non-targeted juvenile aquatic species. Unfortunately, information on the amount and the identity of by-catch species is lacking thus the extent of impact of the fry fishery is not known. In this study, the species composition of milkfish fry fishery by-catch sampled from selected coastal areas that are known to be fry collection sites in the country were identified and assessed through the use of DNA barcoding. Analyses revealed that by-catch fish species of the milkfish fry industry included Black Tiger shrimp (Peneaus monodon), Tarpon (Megalops cyprinoides), Glass perchlets (Ambasis gymnocephalus and Ambasis buruensis), Ladyfish (Elops hawaiensis), Snapper (Lutjanus fulviflamma), Cardinal fishes (Apogon hyalosoma and Sphaeramia orbicularis), Whipfin siver biddy (Gerres filamentosus), Mullet (Liza sp.), Anchovy (Encrasicholina heteroloba), and Tiger perch (Terapon jarbua), almost all of which are potential marketable food fish and culture species. The results of the study provide preliminary information, as well as awareness, on the species composition of milkfish fry by-catch.
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Fast and behavior-selective exploitation of a marine fish targeted by anglers
NASA Astrophysics Data System (ADS)
Alós, Josep; Palmer, Miquel; Rosselló, Rosario; Arlinghaus, Robert
2016-12-01
Harvesting of wild-living animals is often intensive and may selectively target heritable behavioral traits. We studied the exploitation dynamics and the vulnerability consequences of individual heterogeneity in movement-related behaviors in free-ranging pearly razorfish (Xyrichthys novacula). Using underwater-video recording, we firstly document a fast and high exploitation rate of about 60% of the adult population removed in just few days after the opening of the season. Subsequently, we tagged a sample of individuals with acoustic transmitters and studied whether behavioral traits were significant predictors of the vulnerability to angling. Tagged individuals revealed repeatable behaviors in several home range-related traits, suggesting the presence of spatial behavioral types. The individuals surviving the experimental fishery showed only localized and low-intensity movement patterns. Our study provides new insights for understanding the harvesting pressures and selective properties acting on behavioral traits of recreational fishing. Many fish stocks around the globe are today predominantly exploited by recreational fisheries. The fisheries-induced change in fish behavior described here may be therefore widespread, and has the potential to alter food-webs, profitability of the fisheries and to affect stock assessment by eroding catchability in the long-term.
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First-order hydrothermal oxidation kinetics of digested sludge compared with raw sludge.
Shanableh, A; Imteaz, M
2008-09-01
This article presents an assessment of the first-order hydrothermal oxidation kinetics of a selected digested sludge at subcritical (< 374 degrees C) and supercritical (> 374 degrees C) temperatures in the range of 250-460 degrees C. Furthermore, the results were compared with reported oxidation kinetics of raw sludge treated under identical experimental conditions. In the assessment, oxidation was considered to proceed in two steps: (1) decomposition of the particulate, or non-filterable, chemical oxygen demand (PCOD); followed by (2) ultimate oxidation and removal of the total, particulate and soluble, COD. The accumulation and removal of soluble COD (SCOD) was determined from the difference between the rates of sludge decomposition and ultimate oxidation. Using results from batch and continuous-flow hydrothermal treatment experiments, the reacting organic ingredients were separated into groups according to the ease or difficulty at which they were decomposed or removed, with Arrhenius-type activation energy levels assigned to the different groups. The analysis confirmed that within the treatment range of 75% to more than 97% COD removal, the oxidation kinetics of the digested and raw sludges were nearly identical despite differences in the proportions of their original organic ingredients. The original organic ingredients were mostly removed above 75% COD removal, and the oxidation kinetics appeared to be dominated by the removal of acetic acid, an intermediate by-product which constituted 50% to more than 80% of the remaining COD. Furthermore, the oxidation kinetics of both sludge types were consistent with reported first-order oxidation kinetics of pure acetic acid solutions. The resulting kinetic models adequately represented hydrothermal oxidation of digested sludge, in terms of COD and PCOD removals, as well as accumulation and removal of the soluble SCOD.
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NASA Astrophysics Data System (ADS)
Alaoui, Abdallah; El Kacemi, K.; El Ass, K.; Kitane, S.; El Bouzidi, S.
2015-05-01
The leaching capacity of olive mill wastewater (OMW) for pyrolusite mine tailings (MnO2) was evaluated using the Box-Behnken experimental design of response surface methodology. The selected test parameters include the concentration of sulfuric acid, the OMW dosage chemical oxygen demand (COD), the solid/liquid ratio S/ L, and particle size. It was determined that the MnO2 dissolution increased with an increase in the sulfuric acid concentration and the OMW dosage, and with a decrease in the solid/liquid ratio. The particle size does not have significant influence on the manganese recovery. A quadratic polynomial model has been developed to predict the amount of manganese extraction from pyrolusite for other operating conditions that were not directly tested. The leaching ability was evaluated based on manganese recovery (Mn%) and the removal capability of chemical oxygen demand (COD%). The predicted values for the responses agreed well with experimental values; R 2 (correlation coefficient) values for Mn% and COD% were 0.9602 and 0.9687, respectively. Within the design space, the optimum conditions for the lixiviation of MnO2 in terms of manganese recovery and COD removal were established and include [H2SO4] of 3 mol L-1, OMW in range of 23 g L-1 to 25 g L-1 COD, and pulp density in range of 90 g L-1 to 100 g L-1. Under these conditions, the response values generated by the model are Mn% ˜49% and COD% >40%. These values show good agreement with those obtained in the validation test. This study has demonstrated that it is possible to use the olive mill wastewater as a reductant agent to recover manganese from a pyrolusite mining residue.
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Expected rate of fisheries-induced evolution is slow.
Andersen, Ken H; Brander, Keith
2009-07-14
Commercial fisheries exert high mortalities on the stocks they exploit, and the consequent selection pressure leads to fisheries-induced evolution of growth rate, age and size at maturation, and reproductive output. Productivity and yields may decline as a result, but little is known about the rate at which such changes are likely to occur. Fisheries-induced evolution of exploited populations has recently become a subject of concern for policy makers, fisheries managers, and the general public, with prominent calls for mitigating management action. We make a general evolutionary impact assessment of fisheries by calculating the expected rate of fisheries-induced evolution and the consequent changes in yield. Rates of evolution are expected to be approximately 0.1-0.6% per year, and the consequent reductions in fisheries yield are <0.7% per year. These rates are at least a factor of 5 lower than published values based on experiments and analyses of population time series, and we explain why the published rates may be overestimates. Dealing with evolutionary effects of fishing is less urgent than reducing the direct detrimental effects of overfishing on exploited stocks and on their marine ecosystems.
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1981-09-01
in catches made in shallow, mud- and sandflat habitats (B. Stevens, College of Fisheries , Univ. Washington, personal communication ). Considering the...DOUGLAS M. EGGERSDIrbsoUnntd - M FISHERIES RESEARCH INSTITUTE UNIVERSITY OF WASHINGTON of ArmynCrs SEPTEMBER 1981 ~~t~ ~~i; - It - ’ .-J~ . SECURITY...TASK Fisheries Research INsti tute AE OKUI UBR University of Washington Seattle, Washington 98195 j Lni’ 11. CONTROLLING OFFICE NAME AND ADDRESS
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Chen, Zhiqiang; Huang, Long; Wen, Qinxue; Zhang, Huichao; Guo, Zirui
2017-02-01
Four sequence batch reactors (SBRs) fed by fermented sugar cane wastewater were continuously operated under the aerobic dynamic feeding (ADF) mode with different configurations of sludge retention time (SRT), carbon and initial biomass concentrations to enrich polyhydroxyalkanoate (PHA) accumulating mixed microbial cultures (MMCs) from municipal activated sludge. The stability of SBRs was investigated besides the enrichment performance. The microbial community structures of the enriched MMCs were analyzed using terminal restriction fragment length polymorphism (T-RFLP). The optimum operating conditions for the enrichment process were: SRT of 5days, carbon concentration of 2.52g COD/L and initial biomass concentration of 3.65g/L. The best enrichment performance in terms of both operating stability and PHA storage ability of enriched cultures (with the maximum PHA content and PHA storage yield (Y PHA/S ) of 61.26% and 0.68mg COD/mg COD, respectively) was achieved under this condition. Effects of the SRT, carbon concentration and initial biomass concentration on the PHA accumulating MMCs selection process were discussed respectively. A new model including the segmentation of the enrichment process and the effects of SRT on each phase was proposed. Copyright © 2016. Published by Elsevier B.V.
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Potential fitness benefits from mate selection in the Atlantic cod (Gadus morhua).
Rudolfsen, G; Figenschou, L; Folstad, I; Nordeide, J T; Søreng, E
2005-01-01
Little evidence of benefits from female mate choice has been found when males provide no parental care or resources. Yet, good genes models of sexual selection suggest that elaborated male sexual characters are reliable signals of mate quality and that the offspring of males with elaborate sexual ornaments will perform better than those of males with less elaborate ornaments. We used cod (Gadus morhua L.), an externally fertilizing species where males provide nothing but sperm, to examine the potential of optimal mate selection with respect to offspring survival. By applying in vitro fertilizations, we crossed eight females with nine males in all possible combinations and reared each of the 72 sib groups. We found that offspring survival was dependent on which female was mated with which male and that optimal mate selection has the potential to increase mean offspring survival from 31.9 to 55.6% (a 74% increase). However, the size of the male sexual ornaments and sperm quality (i.e. sperm velocity and sperm density) could not predict offspring survival. Thus, even if there may be large fitness benefits of mate selection, we might not yet have identified the male characteristics generating high offspring survival.
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Understanding the individual to implement the ecosystem approach to fisheries management.
Ward, Taylor D; Algera, Dirk A; Gallagher, Austin J; Hawkins, Emily; Horodysky, Andrij; Jørgensen, Christian; Killen, Shaun S; McKenzie, David J; Metcalfe, Julian D; Peck, Myron A; Vu, Maria; Cooke, Steven J
2016-01-01
Ecosystem-based approaches to fisheries management (EAFMs) have emerged as requisite for sustainable use of fisheries resources. At the same time, however, there is a growing recognition of the degree of variation among individuals within a population, as well as the ecological consequences of this variation. Managing resources at an ecosystem level calls on practitioners to consider evolutionary processes, and ample evidence from the realm of fisheries science indicates that anthropogenic disturbance can drive changes in predominant character traits (e.g. size at maturity). Eco-evolutionary theory suggests that human-induced trait change and the modification of selective regimens might contribute to ecosystem dynamics at a similar magnitude to species extirpation, extinction and ecological dysfunction. Given the dynamic interaction between fisheries and target species via harvest and subsequent ecosystem consequences, we argue that individual diversity in genetic, physiological and behavioural traits are important considerations under EAFMs. Here, we examine the role of individual variation in a number of contexts relevant to fisheries management, including the potential ecological effects of rapid trait change. Using select examples, we highlight the extent of phenotypic diversity of individuals, as well as the ecological constraints on such diversity. We conclude that individual phenotypic diversity is a complex phenomenon that needs to be considered in EAFMs, with the ultimate realization that maintaining or increasing individual trait diversity may afford not only species, but also entire ecosystems, with enhanced resilience to environmental perturbations. Put simply, individuals are the foundation from which population- and ecosystem-level traits emerge and are therefore of central importance for the ecosystem-based approaches to fisheries management.
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Understanding the individual to implement the ecosystem approach to fisheries management
Ward, Taylor D.; Algera, Dirk A.; Gallagher, Austin J.; Hawkins, Emily; Horodysky, Andrij; Jørgensen, Christian; Killen, Shaun S.; McKenzie, David J.; Metcalfe, Julian D.; Peck, Myron A.; Vu, Maria; Cooke, Steven J.
2016-01-01
Ecosystem-based approaches to fisheries management (EAFMs) have emerged as requisite for sustainable use of fisheries resources. At the same time, however, there is a growing recognition of the degree of variation among individuals within a population, as well as the ecological consequences of this variation. Managing resources at an ecosystem level calls on practitioners to consider evolutionary processes, and ample evidence from the realm of fisheries science indicates that anthropogenic disturbance can drive changes in predominant character traits (e.g. size at maturity). Eco-evolutionary theory suggests that human-induced trait change and the modification of selective regimens might contribute to ecosystem dynamics at a similar magnitude to species extirpation, extinction and ecological dysfunction. Given the dynamic interaction between fisheries and target species via harvest and subsequent ecosystem consequences, we argue that individual diversity in genetic, physiological and behavioural traits are important considerations under EAFMs. Here, we examine the role of individual variation in a number of contexts relevant to fisheries management, including the potential ecological effects of rapid trait change. Using select examples, we highlight the extent of phenotypic diversity of individuals, as well as the ecological constraints on such diversity. We conclude that individual phenotypic diversity is a complex phenomenon that needs to be considered in EAFMs, with the ultimate realization that maintaining or increasing individual trait diversity may afford not only species, but also entire ecosystems, with enhanced resilience to environmental perturbations. Put simply, individuals are the foundation from which population- and ecosystem-level traits emerge and are therefore of central importance for the ecosystem-based approaches to fisheries management. PMID:27293757
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Fishery Resources and Threatened Coastal Habitats in the Northern Gulf of Mexico (Abstract)
We have explored relationships between selected fishery species of the northern Gulf of Mexico and important features of their habitats. The principal goal of our research is to predict the cumulative effects of habitat alterations on coastal resources and ecosystems. Pink shrimp...
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Shu, Shi; Zhu, Wei; Wang, Shengwei; Ng, Charles Wang Wai; Chen, Yunmin; Chiu, Abraham Chung Fai
2018-01-15
Groundwater pollution by leachate leakage is one of the most common environmental hazards associated with municipal solid waste (MSW) landfill sites. However, landfill leachate contains a large variety of pollutants with widely different concentrations and biotoxicity. Thus, selecting leachate pollutant indicators and levels for identifying breakthrough of barrier systems are key factors in assessing their breakthrough times. This study investigated the transport behavior of leachate pollutants through landfill barrier systems using centrifuge tests and numerical modeling. The overall objective of this study is to investigate breakthrough mechanism to facilitate the establishment of a consistent pollutant threshold concentration for use as a groundwater pollution alert. The specific objective of the study is to identify which pollutant and breakthrough threshold concentration should be used as an indicator in the transport of multiple pollutants through a landfill barrier system. The threshold concentration from the Chinese groundwater quality standards was used in the analysis of the properties of leachates from many landfill sites in China. The time for the chemical oxygen demand (COD) to reach the breakthrough threshold concentration at the bottom of a 2m compacted clay liner was 1.51years according to centrifuge tests, and 1.81years according to numerical modeling. The COD breakthrough times for single and double composite liners were within the range of 16 and 36.58years. Of all the pollutants, COD was found to consistently reach the breakthrough threshold first. Therefore, COD can be selected as the key indicator for pollution alerts and used to assess the environmental risk posed by MSW landfill sites. Copyright © 2017. Published by Elsevier B.V.
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Tang, Bin; Wei, Biao; Wu, De-Cao; Mi, De-Ling; Zhao, Jing-Xiao; Feng, Peng; Jiang, Shang-Hai; Mao, Ben-Jiang
2014-11-01
Eliminating turbidity is a direct effect spectroscopy detection of COD key technical problems. This stems from the UV-visible spectroscopy detected key quality parameters depend on an accurate and effective analysis of water quality parameters analytical model, and turbidity is an important parameter that affects the modeling. In this paper, we selected formazine turbidity solution and standard solution of potassium hydrogen phthalate to study the turbidity affect of UV--visible absorption spectroscopy detection of COD, at the characteristics wavelength of 245, 300, 360 and 560 nm wavelength point several characteristics with the turbidity change in absorbance method of least squares curve fitting, thus analyzes the variation of absorbance with turbidity. The results show, In the ultraviolet range of 240 to 380 nm, as the turbidity caused by particle produces compounds to the organics, it is relatively complicated to test the turbidity affections on the water Ultraviolet spectra; in the visible region of 380 to 780 nm, the turbidity of the spectrum weakens with wavelength increases. Based on this, this paper we study the multiplicative scatter correction method affected by the turbidity of the water sample spectra calibration test, this method can correct water samples spectral affected by turbidity. After treatment, by comparing the spectra before, the results showed that the turbidity caused by wavelength baseline shift points have been effectively corrected, and features in the ultraviolet region has not diminished. Then we make multiplicative scatter correction for the three selected UV liquid-visible absorption spectroscopy, experimental results shows that on the premise of saving the characteristic of the Ultraviolet-Visible absorption spectrum of water samples, which not only improve the quality of COD spectroscopy detection SNR, but also for providing an efficient data conditioning regimen for establishing an accurate of the chemical measurement methods.
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Chen, Baisheng; Wu, Huanan; Li, Sam Fong Yau
2014-03-01
To overcome the challenging task to select an appropriate pathlength for wastewater chemical oxygen demand (COD) monitoring with high accuracy by UV-vis spectroscopy in wastewater treatment process, a variable pathlength approach combined with partial-least squares regression (PLSR) was developed in this study. Two new strategies were proposed to extract relevant information of UV-vis spectral data from variable pathlength measurements. The first strategy was by data fusion with two data fusion levels: low-level data fusion (LLDF) and mid-level data fusion (MLDF). Predictive accuracy was found to improve, indicated by the lower root-mean-square errors of prediction (RMSEP) compared with those obtained for single pathlength measurements. Both fusion levels were found to deliver very robust PLSR models with residual predictive deviations (RPD) greater than 3 (i.e. 3.22 and 3.29, respectively). The second strategy involved calculating the slopes of absorbance against pathlength at each wavelength to generate slope-derived spectra. Without the requirement to select the optimal pathlength, the predictive accuracy (RMSEP) was improved by 20-43% as compared to single pathlength spectroscopy. Comparing to nine-factor models from fusion strategy, the PLSR model from slope-derived spectroscopy was found to be more parsimonious with only five factors and more robust with residual predictive deviation (RPD) of 3.72. It also offered excellent correlation of predicted and measured COD values with R(2) of 0.936. In sum, variable pathlength spectroscopy with the two proposed data analysis strategies proved to be successful in enhancing prediction performance of COD in wastewater and showed high potential to be applied in on-line water quality monitoring. Copyright © 2013 Elsevier B.V. All rights reserved.
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Henriquez, V P; Gonzalez, M T; Licandeo, R; Carvajal, J
2011-12-01
The composition of the metazoan parasite fauna of the rock cod Eleginops maclovinus from three locations in southern Chile was compared to assess the local spatial variation of the community component of their parasitic faunas. A total of 13 108 metazoan parasites (5267 endoparasites and 7841 ectoparasites) belonging to 34 taxa were collected from 268 specimens of E. maclovinus between October 2008 and March 2009. The populations and community quantitative descriptors were estimated. Altogether, 97.4% of the fish were infected with at least one parasite taxon. The most prevalent species were Hypoechinorhynchus magellanicus (Acanthocephala), Caligus rogercresseyi, Lepeophtheirus mugiloides, Clavella adunca (Copepoda) and Similascarophis sp. (Nematoda). Five species are new records for this host: Argulus araucanus, Hirudinea gen. sp1., Hirudinea gen. sp2., Benedenia sp. and Camallanidae gen. sp. A linear discriminant analysis (LDA) showed that the metazoan parasite fauna of E. maclovinus varied qualitatively and quantitatively among three locations, with 89.7% of fish being correctly assigned to their respective locations. This suggested that parasites could be a reliable tool to discriminate individual fish from geographically close locations. There was a weak relationship between the parasite fauna and fish size and there were no accumulations of parasites in the host over time, which could be associated with ontogenetic changes of diet associated with habitat use. © 2011 The Authors. Journal of Fish Biology © 2011 The Fisheries Society of the British Isles.
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50 CFR 622.90 - Recordkeeping and reporting.
Code of Federal Regulations, 2013 CFR
2013-10-01
... ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE FISHERIES OF THE CARIBBEAN, GULF OF MEXICO, AND SOUTH ATLANTIC Red Drum Fishery of the Gulf of Mexico § 622.90 Recordkeeping and reporting. (a) Dealers. A dealer or processor who purchases red drum harvested from the Gulf who is selected to report by the SRD must...
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Das, Shoubhik; Li, Yuehui; Lu, Liang-Qiu; Junge, Kathrin; Beller, Matthias
2016-05-17
This article describes a selective reduction of functionalized amides, including N-acyl amino esters and dipeptides, to the corresponding amines using simple [Rh(acac)(cod)]. The catalyst shows excellent chemoselectivity in the presence of different sensitive functional moieties. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
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The ups and downs of trophic control in continental shelf ecosystems.
Frank, Kenneth T; Petrie, Brian; Shackell, Nancy L
2007-05-01
Traditionally, marine ecosystem structure was thought to be determined by phytoplankton dynamics. However, an integrated view on the relative roles of top-down (consumer-driven) and bottom-up (resource-driven) forcing in large-scale, exploited marine ecosystems is emerging. Long time series of scientific survey data, underpinning the management of commercially exploited species such as cod, are being used to diagnose mechanisms that could affect the composition and relative abundance of species in marine food webs. By assembling published data from studies in exploited North Atlantic ecosystems, we found pronounced geographical variation in top-down and bottom-up trophic forcing. The data suggest that ecosystem susceptibility to top-down control and their resiliency to exploitation are related to species richness and oceanic temperature conditions. Such knowledge could be used to produce ecosystem guidelines to regulate and manage fisheries in a sustainable fashion.
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The use of archived tags in retrospective genetic analysis of fish.
Bonanomi, Sara; Therkildsen, Nina Overgaard; Hedeholm, Rasmus Berg; Hemmer-Hansen, Jakob; Nielsen, Einar E
2014-05-01
Collections of historical tissue samples from fish (e.g. scales and otoliths) stored in museums and fisheries institutions are precious sources of DNA for conducting retrospective genetic analysis. However, in some cases, only external tags used for documentation of spatial dynamics of fish populations have been preserved. Here, we test the usefulness of fish tags as a source of DNA for genetic analysis. We extract DNA from historical tags from cod collected in Greenlandic waters between 1950 and 1968. We show that the quantity and quality of DNA recovered from tags is comparable to DNA from archived otoliths from the same individuals. Surprisingly, levels of cross-contamination do not seem to be significantly higher in DNA from external (tag) than internal (otolith) sources. Our study therefore demonstrates that historical tags can be a highly valuable source of DNA for retrospective genetic analysis of fish. © 2013 John Wiley & Sons Ltd.
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Directional selection by fisheries and the timing of sockeye salmon (Oncorhynchus nerka) migrations.
Quinn, Thomas P; Hodgson, Sayre; Flynn, Lucy; Hilborn, Ray; Rogers, Donald E
2007-04-01
The timing of migration from feeding to breeding areas is a critical link between the growth and survival of adult animals, their reproduction, and the fitness of their progeny. Commercial fisheries often catch a large fraction of the migrants (e.g., salmon), and exploitation rates can vary systematically over the fishing season. We examined daily records of sockeye salmon (Oncorhynchus nerka) in the Egegik and Ugashik management districts in Bristol Bay, Alaska (USA), for evidence of such temporally selective fishing. In recent years, the early migrants have experienced lower fishing rates than later migrants, especially in the Egegik district, and the median migration date of the fish escaping the fisheries has been getting progressively earlier in both districts. Moreover, the overall runs (catch and escapement) in the Egegik district and, to a lesser extent the Ugashik district, have been getting earlier, as predicted in response to the selection on timing. The trends in timing were not correlated with sea surface temperature in the region of the North Pacific Ocean where the salmon tend to concentrate, but the trends in the two districts were correlated with each other, indicating that there may be some common environmental influence in addition to the effect of selection. Despite the selection, both groups of salmon have remained productive. We hypothesize that this resilience may result from representation of all component populations among the early and late migrants, so that the fisheries have not eliminated entire populations, and from density-dependent processes that may have helped maintain the productivity of these salmon populations.
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Expected rate of fisheries-induced evolution is slow
Andersen, Ken H.; Brander, Keith
2009-01-01
Commercial fisheries exert high mortalities on the stocks they exploit, and the consequent selection pressure leads to fisheries-induced evolution of growth rate, age and size at maturation, and reproductive output. Productivity and yields may decline as a result, but little is known about the rate at which such changes are likely to occur. Fisheries-induced evolution of exploited populations has recently become a subject of concern for policy makers, fisheries managers, and the general public, with prominent calls for mitigating management action. We make a general evolutionary impact assessment of fisheries by calculating the expected rate of fisheries-induced evolution and the consequent changes in yield. Rates of evolution are expected to be ≈0.1–0.6% per year, and the consequent reductions in fisheries yield are <0.7% per year. These rates are at least a factor of 5 lower than published values based on experiments and analyses of population time series, and we explain why the published rates may be overestimates. Dealing with evolutionary effects of fishing is less urgent than reducing the direct detrimental effects of overfishing on exploited stocks and on their marine ecosystems. PMID:19564596
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Krishnamoorthy, Navaneethakrishnan; Gajendrarao, Poornima; Eom, Soo Hyun; Kwon, Yong Jung; Cheong, Gang-Won; Lee, Keun Woo
2008-08-01
In Bacillus subtilis, CodW peptidase and CodX ATPase function together as a distinctive ATP-dependent protease called CodWX, which participates in protein degradation and regulates cell division. The molecular structure of CodX and the assembly structure of CodW-CodX have not yet been resolved. Here we present the first three-dimensional structure of CodX N-terminal (N) and C-terminal (C) domain including possible structure of intermediate (I) domain based on the crystal structure of homologous Escherichia coli HslU ATPase. Moreover, the biologically relevant CodWX (W(6)W(6)X(6)) octadecamer complex structure was constructed using the recently identified CodW-HslU hybrid crystal structure. Molecular dynamics (MD) simulation shows a reasonably stable structure of modeled CodWX and explicit behavior of key segments in CodX N and C domain: nucleotide binding residues, GYVG pore motif and CodW-CodX interface. Predicted structure of the possible I domain is flexible in nature with highly coiled hydrophobic region (M153-M206) that could favor substrate binding and entry. Electrostatic surface potential observation unveiled charge complementarity based CodW-CodX interaction pattern could be a possible native interaction pattern in the interface of CodWX. CodX GYVG pore motif structural features, flexible nature of glycine (G92 and G95) residues and aromatic ring conformation preserved Y93 indicated that it may follow the similar mode during the proteolysis mechanism as in the HslU closed state. This molecular modeling study uncovers the significance of CodX N and C domain in CodWX complex and provides possible explanations which would be helpful to understand the CodWX-dependent proteolysis mechanism of B. subtilis.
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The role of experiments in understanding fishery-induced evolution
Conover, David O; Baumann, Hannes
2009-01-01
Evidence of fishery-induced evolution has been accumulating rapidly from various avenues of investigation. Here we review the knowledge gained from experimental approaches. The strength of experiments is in their ability to disentangle genetic from environmental differences. Common garden experiments have provided direct evidence of adaptive divergence in the wild and therefore the evolvability of various traits that influence production in numerous species. Most of these cases involve countergradient variation in physiological, life history, and behavioral traits. Selection experiments have provided examples of rapid life history evolution and, more importantly, that fishery-induced selection pressures cause simultaneous divergence of not one but a cluster of genetically and phenotypically correlated traits that include physiology, behavior, reproduction, and other life history characters. The drawbacks of experiments are uncertainties in the scale-up from small, simple environments to larger and more complex systems; the concern that taxons with short life cycles used for experimental research are atypical of those of harvested species; and the difficulty of adequately simulating selection due to fishing. Despite these limitations, experiments have contributed greatly to our understanding of fishery-induced evolution on both empirical and theoretical levels. Future advances will depend on integrating knowledge from experiments with those from modeling, field studies, and molecular genetic approaches. PMID:25567880
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NASA Astrophysics Data System (ADS)
Rodríguez-Climent, Sílvia; Alcaraz, Carles; Caiola, Nuno; Ibáñez, Carles; Nebra, Alfonso; Muñoz-Camarillo, Gloria; Casals, Frederic; Vinyoles, Dolors; de Sostoa, Adolfo
2012-12-01
Multimesh nylon gillnets were set in three Ebro Delta (North-East of Spain) lagoons to determine mesh selectivity for the inhabiting fish community. Each gillnet consisted on a series of twelve panels of different mesh size (ranging from 5.0 to 55.0 mm bar length) randomly distributed. The SELECT method (Share Each Length's Catch Total) was used to estimate retention curves through five models: normal location, normal scale, gamma, lognormal and inverse Gaussian. Each model was fitted twice, under the assumptions of equal and proportional to mesh size fishing effort, but no differences were found between approaches. A possible situation of overfishing in the lagoons, where artisanal fisheries are carried out with a low surveillance effort, was assessed using a vulnerable species inhabiting these brackish waters as case study: the sand smelt, Atherina boyeri. The minimum size for its fishery has not been established, thus remaining under an uncontrolled exploitation situation. Therefore, a Minimum Landing Size (MLS) is proposed based on sexual maturity data. The importance of establishing an adequate MLS and regulate mesh sizes in order to respect natural maturation length is discussed, as well as, the proposal of other measures to improve A. boyeri fishery management.
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The fish and fisheries of Jones Bank and the wider Celtic Sea
NASA Astrophysics Data System (ADS)
Martinez, I.; Ellis, J. R.; Scott, B.; Tidd, A.
2013-10-01
The Celtic Sea is a diverse fishing ground that supports important commercial fisheries for a range of demersal fish, large and small-bodied pelagic fish and a variety of cephalopods and other shellfish. A regional overview of the main commercial fish stocks of the Celtic Sea and of the fish that occur in the vicinity of Jones Bank are provided through analyses of landings data from English and Welsh vessels, and from scientific trawl surveys. Dedicated smaller scale sampling via trawl surveys combined with baited cameras on and around the Jones Bank were also analysed to investigate the importance of sandbank habitats with attention paid to the differences in the species occurring on the top of the bank in comparison to adjacent off-bank habitats. Official landing statistics for UK (English and Welsh) vessels indicated that the predominant commercial demersal species in ICES Divisions VIIg,h (in terms of quantities landed) were anglerfish, megrim, pollack and skates (Rajidae). There were, however, regional differences in the distribution of fish and fisheries, and the area surrounding Jones Bank (ICES Rectangles 28E1 and 28E2) supports fisheries for megrim, anglerfish, skates, hake, ling and turbot, with otter trawl, gillnet and beam trawl the main gears used. Recent survey data collected with GOV (Grande Ouverture Verticale) trawl from the Celtic Sea (ICES Divisions VIIe-h, 2007-2010) were used to highlight the broad scale distribution of the main fish assemblages in the Celtic Sea. Analyses of the fish and cephalopod catches from these surveys indicated that there were four broad assemblages in the area, including (i) a region around the Cornwall (which will also be partly influenced by the necessity to use rockhopper ground gear on these rough grounds), (ii) the shallower regions of the north-western Celtic Sea (including parts of the Bristol Channel), (iii) the deeper parts of the outer shelf and (iv) the central Celtic Sea. These data also provided information on the ichthyofauna of the Jones Bank. Further site-specific data for bank and off-bank habitats were collected during dedicated surveys on the Jones Bank in 2008 using commercial trawlers and baited camera deployments. Twenty-three species were recorded on the top of the bank, where horse mackerel, haddock and boarfish were the most abundant species; 18 species were found along the slope of the bank (with blue whiting, poor cod, hake and horse mackerel predominant) and 18 species observed off the bank (where catches were dominated by blue whiting, poor cod and hake). The differences between camera and trawls were important with cameras only picking up 28% of the species seen in the trawls. However both camera and trawl results suggest that some species are very habitat specific, with species such as haddock only observed on the top of the bank, whilst Nephrops norvegicus was abundant on the flat areas off the bank but was infrequent on the top of the bank. These results suggest that future surveys of offshore sandbank habitats should stratify sampling more specifically to deal with smaller scale features that may play an important role in providing a greater range of habitats than just their relative size would suggest.
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Effect of organic nitrogen concentration on the efficiency of trickling filters
NASA Astrophysics Data System (ADS)
Kopeć, Łukasz; Drewnowski, Jakub; Fernandez-Morales, F. J.
2018-02-01
The study was conducted in Poland at six selected wastewater treatment plants (WWTP) based on the trickling filters Bioclere® technology. The aim of the study was to find the relationship between the influent organic nitrogen concentration and the purification efficiency expressed as effluent COD concentration. In the tests performed, the COD to BOD5 relationship was close to 2 and the ratio of BOD5 to TN was lower than 4. The research indicated that this specific chemical composition of raw wastewater causes appearance of filamentous bacteria on the surface of trickling filter filling and strongly affect the effluent quality.
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Krasnov, Aleksei; Kileng, Øyvind; Skugor, Stanko; Jørgensen, Sven Martin; Afanasyev, Sergey; Timmerhaus, Gerrit; Sommer, Ann-Inger; Jensen, Ingvill
2013-07-01
Genome sequencing combined with transcriptome profiling promotes exploration of defence against pathogens and discovery of immune genes. Based on sequences from the recently released genome of Atlantic cod, a genome-wide oligonucleotide microarray (ACIQ-1) was designed and used for analyses of gene expression in the brain during infection with nervous necrosis virus (NNV). A challenge experiment with NNV was performed with Atlantic cod juveniles and brain samples from virus infected and uninfected fish were used for microarray analysis. Expression of virus induced genes increased at 5 days post challenge and persisted at stable level to the last sampling at 25 days post challenge. A large fraction of the up-regulated genes (546 features) were known or expected to have immune functions and most of these have not previously been characterized in Atlantic cod. Transcriptomic changes induced by the virus involved strong activation of genes associated with interferon and tumour necrosis factor related responses and acute inflammation. Up-regulation of genes involved in adaptive immunity suggested a rapid recruitment of B and T lymphocytes to the NNV infected brain. QPCR analyses of 15 candidate genes of innate immunity showed rapid induction by poly(I:C) in Atlantic cod larvae cells suggesting an antiviral role. Earliest and greatest expression changes after poly I:C stimulation was observed for interferon regulatory factors IRF4 and IRF7. Comparative studies between teleost species provided new knowledge about the evolution of innate antiviral immunity in fish. A number of genes is present or responds to viruses only in fish. Innate immunity of Atlantic cod is characterized by selective expansion of several medium-sized multigene families with ribose binding domains. An interesting finding was the high representation of three large gene families among the early antiviral genes, including tripartite motif proteins (TRIM) and proteins with PRY-SPRY and NACHT domains. The latter two with respectively 52 and 114 members in Atlantic cod have gone through expansions in different groups of fish. These proteins most likely have ligand binding properties and their propagation could be linked to the loss of MHC class II in the Atlantic cod genome. Copyright © 2013 Elsevier Ltd. All rights reserved.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Castillo, E.; Vergara, M.; Moreno, Y.
2007-07-01
This paper describes the feasibility of an aerobic system (rotating biological contactor, RBC) and a biological anaerobic system (upward-flow anaerobic sludge bed reactor) at small scale for the treatment of a landfill leachate. In the first phase of the aerobic system study, a cyclic-batch RBC system was used to select perforated acetate discs among three different acetate disc configurations. These discs were chosen on the basis of high COD removal (65%) and biological stability. In the second phase, the RBC system (using four stages) was operated continuously at different hydraulic retention times (HRT), at different rotational speeds, and with varyingmore » organic concentrations of the influent leachate (2500-9000 mg L{sup -1}). Forty percent of the total surface area of each perforated disc was submerged in the leachate. A COD removal of about 52% was obtained at an HRT of 24 h and a rotational speed of 6 rpm. For the anaerobic system, the reactor was evaluated with a volumetric organic load of 3273 g-COD m{sup -3} day{sup -1} at an HRT of 54, 44, 39, 24 and 17 h. At these conditions, the system reached COD removal efficiencies of 62%, 61%, 59%, 44% and 24%, respectively.« less
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2015-01-01
Activation of a catalyst [IrCl(COD)(IMes)] (IMes = 1,3-bis(2,4,6-trimethylphenyl)imidazol-2-ylidene; COD = cyclooctadiene)] for signal amplification by reversible exchange (SABRE) was monitored by in situ hyperpolarized proton NMR at 9.4 T. During the catalyst-activation process, the COD moiety undergoes hydrogenation that leads to its complete removal from the Ir complex. A transient hydride intermediate of the catalyst is observed via its hyperpolarized signatures, which could not be detected using conventional nonhyperpolarized solution NMR. SABRE enhancement of the pyridine substrate can be fully rendered only after removal of the COD moiety; failure to properly activate the catalyst in the presence of sufficient substrate can lead to irreversible deactivation consistent with oligomerization of the catalyst molecules. Following catalyst activation, results from selective RF-saturation studies support the hypothesis that substrate polarization at high field arises from nuclear cross-relaxation with hyperpolarized 1H spins of the hydride/orthohydrogen spin bath. Importantly, the chemical changes that accompanied the catalyst’s full activation were also found to endow the catalyst with water solubility, here used to demonstrate SABRE hyperpolarization of nicotinamide in water without the need for any organic cosolvent—paving the way to various biomedical applications of SABRE hyperpolarization methods. PMID:25372972
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Fishing diseased abalone to promote yield and conservation
Ben-Horin, Tal; Bidegain, Gorka; Lenihan, Hunter S.
2016-01-01
Past theoretical models suggest fishing disease-impacted stocks can reduce parasite transmission, but this is a good management strategy only when the exploitation required to reduce transmission does not overfish the stock. We applied this concept to a red abalone fishery so impacted by an infectious disease (withering syndrome) that stock densities plummeted and managers closed the fishery. In addition to the non-selective fishing strategy considered by past disease-fishing models, we modelled targeting (culling) infected individuals, which is plausible in red abalone because modern diagnostic tools can determine infection without harming landed abalone and the diagnostic cost is minor relative to the catch value. The non-selective abalone fishing required to eradicate parasites exceeded thresholds for abalone sustainability, but targeting infected abalone allowed the fishery to generate yield and reduce parasite prevalence while maintaining stock densities at or above the densities attainable if the population was closed to fishing. The effect was strong enough that stock and yield increased even when the catch was one-third uninfected abalone. These results could apply to other fisheries as the diagnostic costs decline relative to catch value. PMID:26880843
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Fishing diseased abalone to promote yield and conservation.
Ben-Horin, Tal; Lafferty, Kevin D; Bidegain, Gorka; Lenihan, Hunter S
2016-03-05
Past theoretical models suggest fishing disease-impacted stocks can reduce parasite transmission, but this is a good management strategy only when the exploitation required to reduce transmission does not overfish the stock. We applied this concept to a red abalone fishery so impacted by an infectious disease (withering syndrome) that stock densities plummeted and managers closed the fishery. In addition to the non-selective fishing strategy considered by past disease-fishing models, we modelled targeting (culling) infected individuals, which is plausible in red abalone because modern diagnostic tools can determine infection without harming landed abalone and the diagnostic cost is minor relative to the catch value. The non-selective abalone fishing required to eradicate parasites exceeded thresholds for abalone sustainability, but targeting infected abalone allowed the fishery to generate yield and reduce parasite prevalence while maintaining stock densities at or above the densities attainable if the population was closed to fishing. The effect was strong enough that stock and yield increased even when the catch was one-third uninfected abalone. These results could apply to other fisheries as the diagnostic costs decline relative to catch value. © 2016 The Author(s).
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Fishing diseased abalone to promote yield and conservation
Ben-Horin, Tal; Lafferty, Kevin D.; Bidegain, Gorka; Lenihan, Hunter S.
2016-01-01
Past theoretical models suggest fishing disease-impacted stocks can reduce parasite transmission, but this is a good management strategy only when the exploitation required to reduce transmission does not overfish the stock. We applied this concept to a red abalone fishery so impacted by an infectious disease (withering syndrome) that stock densities plummeted and managers closed the fishery. In addition to the non-selective fishing strategy considered by past disease-fishing models, we modelled targeting (culling) infected individuals, which is plausible in red abalone because modern diagnostic tools can determine infection without harming landed abalone and the diagnostic cost is minor relative to the catch value. The non-selective abalone fishing required to eradicate parasites exceeded thresholds for abalone sustainability, but targeting infected abalone allowed the fishery to generate yield and reduce parasite prevalence while maintaining stock densities at or above the densities attainable if the population was closed to fishing. The effect was strong enough that stock and yield increased even when the catch was one-third uninfected abalone. These results could apply to other fisheries as the diagnostic costs decline relative to catch value.
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Molecular architecture of the ATP-dependent CodWX protease having an N-terminal serine active site
Kang, Min Suk; Kim, Soon Rae; Kwack, Pyeongsu; Lim, Byung Kook; Ahn, Sung Won; Rho, Young Min; Seong, Ihn Sik; Park, Seong-Chul; Eom, Soo Hyun; Cheong, Gang-Won; Chung, Chin Ha
2003-01-01
CodWX in Bacillus subtilis is an ATP-dependent, N-terminal serine protease, consisting of CodW peptidase and CodX ATPase. Here we show that CodWX is an alkaline protease and has a distinct molecular architecture. ATP hydrolysis is required for the formation of the CodWX complex and thus for its proteolytic function. Remarkably, CodX has a ‘spool-like’ structure that is formed by interaction of the intermediate domains of two hexameric or heptameric rings. In the CodWX complex, CodW consisting of two stacked hexameric rings (WW) binds to either or both ends of a CodX double ring (XX), forming asymmetric (WWXX) or symmetric cylindrical particles (WWXXWW). CodWX can also form an elongated particle, in which an additional CodX double ring is bound to the symmetric particle (WWXXWWXX). In addition, CodWX is capable of degrading EzrA, an inhibitor of FtsZ ring formation, implicating it in the regulation of cell division. Thus, CodWX appears to constitute a new type of protease that is distinct from other ATP-dependent proteases in its structure and proteolytic mechanism. PMID:12805205
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Silva, Fernando; Campanari, Sabrina; Matteo, Stefania; Valentino, Francesco; Majone, Mauro; Villano, Marianna
2017-07-25
A sequencing batch reactor (SBR) is typically used for selecting mixed microbial cultures (MMC) for polyhydroxyalkanoate (PHA) production. Since many waste streams suitable as process feedstock for PHA production are nitrogen-deficient, a nutrient supply in the SBR is typically required to allow for efficient microbial growth. The scope of this study was to devise a nitrogen feeding strategy which allows controlling the nitrogen levels during the feast and famine regime of a lab-scale SBR, thereby selecting for PHA-storing microorganisms. At the beginning of the cycle the reactor was fed with a synthetic mixture of acetic and propionic acids at an overall organic load rate of 8.5gCODL -1 d -1 (i.e. 260CmmolL -1 d -1 ), whereas nitrogen (in the form of ammonium sulphate) was added either simultaneously to the carbon feed (coupled feeding strategy) or after the end of the feast phase (uncoupled feeding strategy). As a main result, PHA production was more than doubled (up to about 1300±64mgCODL -1 ) when carbon and nitrogen were separately fed and the higher PHA production also corresponded to an 82% increase in the polymer HV content (up to 20±1%, wtwt -1 ). Three SBR runs were performed with the uncoupled carbon and nitrogen feeding at different carbon to nitrogen (C/N) ratios (of 14.3, 17.9, and 22.3CmolNmol -1 , respectively) which were varied by progressively reducing the concentration of the nitrogen feeding. In spite of a comparable PHA storage yield at 14.3 and 17.9CmolNmol -1 (0.41±0.05 gCOD PHA gCOD VFA -1 and 0.38±0.05 gCOD PHA gCOD VFA -1 , respectively), the storage response of the selected MMC significantly decreased when the C/N ratio was set at the highest investigated value. Notably, an increase in this parameter also resulted in a change in the HV content in the polymer regardless the composition of the organic acids solution. Copyright © 2016 Elsevier B.V. All rights reserved.
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Hur, Jin; Cho, Jinwoo
2012-01-01
The development of a real-time monitoring tool for the estimation of water quality is essential for efficient management of river pollution in urban areas. The Gap River in Korea is a typical urban river, which is affected by the effluent of a wastewater treatment plant (WWTP) and various anthropogenic activities. In this study, fluorescence excitation-emission matrices (EEM) with parallel factor analysis (PARAFAC) and UV absorption values at 220 nm and 254 nm were applied to evaluate the estimation capabilities for biochemical oxygen demand (BOD), chemical oxygen demand (COD), and total nitrogen (TN) concentrations of the river samples. Three components were successfully identified by the PARAFAC modeling from the fluorescence EEM data, in which each fluorophore group represents microbial humic-like (C1), terrestrial humic-like organic substances (C2), and protein-like organic substances (C3), and UV absorption indices (UV(220) and UV(254)), and the score values of the three PARAFAC components were selected as the estimation parameters for the nitrogen and the organic pollution of the river samples. Among the selected indices, UV(220), C3 and C1 exhibited the highest correlation coefficients with BOD, COD, and TN concentrations, respectively. Multiple regression analysis using UV(220) and C3 demonstrated the enhancement of the prediction capability for TN.
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Trends in the capture fisheries in Cuyo East Pass, Philippines
San Diego, Tee-Jay A.; Fisher, William L.
2014-01-01
Findings are presented of a comprehensive analysis of time series catch and effort data from 2000 to 2006 collected from a multi-species, multi-gear and two-sector (municipal and commercial) capture fisheries in Cuyo East Pass, Philippines. Multivariate techniques were used to determine temporal variation in species composition and gear selectivity that corresponded with annual trends in catch and effort. Distinct annual variation in species composition was found for five fisheries classified according to sector-gear combination, corresponding decline in catch diversity, noted shifts in gears used, and an erratic CPUE trend as a result of catch variation. These patterns and trends illustrate the occurrence of ecosystem overfishing for Cuyo East Pass. Our approach provided a holistic representation of the fishing situation, condition of the fisheries and corresponding implications to the ecosystem, fitting well within the context of the ecosystem approach to fisheries management.
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Aguilera, Stacy E; Cole, Jennifer; Finkbeiner, Elena M; Le Cornu, Elodie; Ban, Natalie C; Carr, Mark H; Cinner, Joshua E; Crowder, Larry B; Gelcich, Stefan; Hicks, Christina C; Kittinger, John N; Martone, Rebecca; Malone, Daniel; Pomeroy, Carrie; Starr, Richard M; Seram, Sanah; Zuercher, Rachel; Broad, Kenneth
2015-01-01
Globally, small-scale fisheries are influenced by dynamic climate, governance, and market drivers, which present social and ecological challenges and opportunities. It is difficult to manage fisheries adaptively for fluctuating drivers, except to allow participants to shift effort among multiple fisheries. Adapting to changing conditions allows small-scale fishery participants to survive economic and environmental disturbances and benefit from optimal conditions. This study explores the relative influence of large-scale drivers on shifts in effort and outcomes among three closely linked fisheries in Monterey Bay since the Magnuson-Stevens Fisheries Conservation and Management Act of 1976. In this region, Pacific sardine (Sardinops sagax), northern anchovy (Engraulis mordax), and market squid (Loligo opalescens) fisheries comprise a tightly linked system where shifting focus among fisheries is a key element to adaptive capacity and reduced social and ecological vulnerability. Using a cluster analysis of landings, we identify four modes from 1974 to 2012 that are dominated (i.e., a given species accounting for the plurality of landings) by squid, sardine, anchovy, or lack any dominance, and seven points of transition among these periods. This approach enables us to determine which drivers are associated with each mode and each transition. Overall, we show that market and climate drivers are predominantly attributed to dominance transitions. Model selection of external drivers indicates that governance phases, reflected as perceived abundance, dictate long-term outcomes. Our findings suggest that globally, small-scale fishery managers should consider enabling shifts in effort among fisheries and retaining existing flexibility, as adaptive capacity is a critical determinant for social and ecological resilience.
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Federal Register 2010, 2011, 2012, 2013, 2014
2011-07-05
... for the more selective, directed fishing categories, and be a de facto reallocation of quota shares... allowing a de facto ``incidental catch'' fishery in the Gulf of Mexico, in violation of the ICCAT... regarding post-release mortality, makes it difficult to quantify now the effect of the weak hook requirement...
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Federal Register 2010, 2011, 2012, 2013, 2014
2010-10-12
... (NMFS), National Oceanic and Atmospheric Administration (NOAA), Commerce. ACTION: Proposed rule; request... ``NOAA-NMFS-2010-0091'' in the keyword search, then check the box labeled ``Select to find documents... Light, NC) and 28[deg]35.1' N. lat. (due east of the NASA Vehicle Assembly Building, Cape Canaveral, FL...
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Hu, Yong; Jing, Zhaoqian; Sudo, Yuta; Niu, Qigui; Du, Jingru; Wu, Jiang; Li, Yu-You
2015-07-01
The effect of the chemical oxygen demand/sulfate (COD/SO4(2-)) ratio on the anaerobic treatment of synthetic chemical wastewater containing acetate, ethanol, and sulfate, was investigated using a UASB reactor. The experimental results show that at a COD/SO4(2-) ratio of 20 and a COD loading rate of 25.2gCODL(-1)d(-1), a COD removal of as high as 87.8% was maintained. At a COD/SO4(2-) ratio of 0.5 (sulfate concentration 6000mgL(-1)), however, the COD removal was 79.2% and the methane yield was 0.20LCH4gCOD(-1). The conversion of influent COD to methane dropped from 80.5% to 54.4% as the COD/SO4(2-) ratio decreased from 20 to 0.5. At all the COD/SO4(2-) ratios applied, over 79.4% of the total electron flow was utilized by methane-producing archaea (MPA), indicating that methane fermentation was the predominant reaction. The majority of the methane was produced by acetoclastic MPA at high COD/SO4(2-) ratios and both acetoclastic and hydrogenthrophic MPA at low COD/SO4(2-) ratios. Only at low COD/SO4(2-) ratios were SRB species such as Desulfovibrio found to play a key role in ethanol degradation, whereas all the SRB species were found to be incomplete oxidizers at both high and low COD/SO4(2-) ratios. Copyright © 2015 Elsevier Ltd. All rights reserved.
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Improved COD Measurements for Organic Content in Flowback Water with High Chloride Concentrations.
Cardona, Isabel; Park, Ho Il; Lin, Lian-Shin
2016-03-01
An improved method was used to determine chemical oxygen demand (COD) as a measure of organic content in water samples containing high chloride content. A contour plot of COD percent error in the Cl(-)-Cl(-):COD domain showed that COD errors increased with Cl(-):COD. Substantial errors (>10%) could occur in low Cl(-):COD regions (<300) for samples with low (<10 g/L) and high chloride concentrations (>25 g/L). Applying the method to flowback water samples resulted in COD concentrations ranging in 130 to 1060 mg/L, which were substantially lower than the previously reported values for flowback water samples from Marcellus Shale (228 to 21 900 mg/L). It is likely that overestimations of COD in the previous studies occurred as result of chloride interferences. Pretreatment with mercuric sulfate, and use of a low-strength digestion solution, and the contour plot to correct COD measurements are feasible steps to significantly improve the accuracy of COD measurements.
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André, L; Pauss, A; Ribeiro, T
2017-03-01
The chemical oxygen demand (COD) is an essential parameter in waste management, particularly when monitoring wet anaerobic digestion processes. An adapted method to determine COD was developed for solid waste (total solids >15%). This method used commercial COD tubes and did not require sample dilution. A homemade plastic weighing support was used to transfer the solid sample into COD tubes. Potassium hydrogen phthalate and glucose used as standards showed an excellent repeatability. A small underestimation of the theoretical COD value (standard values around 5% lower than theoretical values) was also observed, mainly due to the intrinsic COD of the weighing support and to measurement uncertainties. The adapted COD method was tested using various solid wastes in the range of 1-8 mg COD , determining the COD of dried and ground cellulose, cattle manure, straw and a mixed-substrate sample. This new adapted method could be used to monitor and design dry anaerobic digestion processes.
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Suvilampi, J; Lehtomäki, A; Rintala, J
2003-07-01
A combined thermophilic-mesophilic wastewater treatment was studied using a laboratory-scale thermophilic activated sludge process (ASP) followed by mesophilic ASP or a thermophilic suspended carrier biofilm process (SCBP) followed by mesophilic ASP, both systems treating diluted molasses (dilution factor 1:500 corresponding GF/A-filtered COD (COD(filt)) of 1900+/-190 mgl(-1)). With hydraulic retention times (HRTs) of 12-18 h the thermophilic ASP and thermophilic SCBP removed 60+/-13% and 62+/-7% of COD(filt), respectively, with HRT of 8 h the removals were 48+/-1% and 69+/-4%. The sludge volume index (SVI) was notably lower in the thermophilic SCBP (measured from suspended sludge) than in the thermophilic ASP. Under the lowest HRT the mesophilic ASP gave better performance (as SVI, COD(filt), and COD(tot) removals) after the thermophilic SCBP than after the thermophilic ASP. Measured sludge yields were low (less than 0.1 kg suspended solids (SS) kg COD(filt removed)(-1)) in all processes. Both thermophilic treatments removed 80-85% of soluble COD (COD(sol)) whereas suspended COD (COD(susp)) and colloidal COD (COD(col)) were increased. Both mesophilic post-treatments removed all COD(col) and most of the COD(susp) from the thermophilic effluents. In conclusion, combined thermophilic-mesophilic treatment appeared to be easily operable and produced high effluent quality.
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NASA Technical Reports Server (NTRS)
Maughan, P. M.; Marmelstein, A. D.; Hecht, K.; Broadhead, G. C.; Alverson, F. G.; Peckham, C. G.
1971-01-01
A study to evaluate the applications of remote sensing in commercial fishing is reported, and the basis for effective communications between NASA and the U.S. fishing industry are established. Detailed information is presented in the following areas: organization of the fishing complex and communication levels within and between the components; organization of the fishing industry and the communications within and between both selected fisheries and various industry groups; relationships and communications between federal, state, and local government agencies and the fishing industry; relationships and communications between international and regional fisheries commissions; and intergovernmental agency relationships relevant to the fishing industry. It will be necessary to educate those individuals having access to the techniques and resultant data, and channels for distribution of the information to selected fisheries are recommended. Procedures for feedback information loops are also established.
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Food webs and carbon flux in the Barents Sea
NASA Astrophysics Data System (ADS)
Wassmann, Paul; Reigstad, Marit; Haug, Tore; Rudels, Bert; Carroll, Michael L.; Hop, Haakon; Gabrielsen, Geir Wing; Falk-Petersen, Stig; Denisenko, Stanislav G.; Arashkevich, Elena; Slagstad, Dag; Pavlova, Olga
2006-10-01
Within the framework of the physical forcing, we describe and quantify the key ecosystem components and basic food web structure of the Barents Sea. Emphasis is given to the energy flow through the ecosystem from an end-to-end perspective, i.e. from bacteria, through phytoplankton and zooplankton to fish, mammals and birds. Primary production in the Barents is on average 93 g C m -2 y -1, but interannually highly variable (±19%), responding to climate variability and change (e.g. variations in Atlantic Water inflow, the position of the ice edge and low-pressure pathways). The traditional focus upon large phytoplankton cells in polar regions seems less adequate in the Barents, as the cell carbon in the pelagic is most often dominated by small cells that are entangled in an efficient microbial loop that appears to be well coupled to the grazing food web. Primary production in the ice-covered waters of the Barents is clearly dominated by planktonic algae and the supply of ice biota by local production or advection is small. The pelagic-benthic coupling is strong, in particular in the marginal ice zone. In total 80% of the harvestable production is channelled through the deep-water communities and benthos. 19% of the harvestable production is grazed by the dominating copepods Calanus finmarchicus and C. glacialis in Atlantic or Arctic Water, respectively. These two species, in addition to capelin ( Mallotus villosus) and herring ( Clupea harengus), are the keystone organisms in the Barents that create the basis for the rich assemblage of higher trophic level organisms, facilitating one of the worlds largest fisheries (capelin, cod, shrimps, seals and whales). Less than 1% of the harvestable production is channelled through the most dominating higher trophic levels such as cod, harp seals, minke whales and sea birds. Atlantic cod, seals, whales, birds and man compete for harvestable energy with similar shares. Climate variability and change, differences in recruitment, variable resource availability, harvesting restrictions and management schemes will influence the resource exploitation between these competitors, that basically depend upon the efficient energy transfer from primary production to highly successful, lipid-rich zooplankton and pelagic fishes.
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Loturco, Irineu; Pereira, Lucas A.; Moraes, José E.; Kitamura, Katia; Cal Abad, César C.; Kobal, Ronaldo; Nakamura, Fábio Y.
2017-01-01
The aim of this study was to evaluate the relation between the maximum mean propulsive power (MPP) obtained in the loaded jump squat (JS) and half squat (HS) exercises and functional performances in vertical jumps, 40 m linear speed (VEL) and change-of-direction (COD) tests, using the median split technique. Twenty-two male rugby sevens players from the Brazilian National Olympic Team (Rio-2016) performed vertical jumping tests (squat and countermovement jumps [SJ and CMJ]), JS and HS exercises, COD speed test and sprinting velocity in 40 m, in this order. Based on the results of the MPP in the JS and HS exercises the participants were divided, using the median split, into four groups as follows: higher JS, lower JS, higher HS, and lower HS. Between-group differences in the functional tasks were detected via magnitude-based inferences. The athletes with higher MPP in the JS were capable of jumping higher and sprinting faster (including the COD speed test) than their weaker counterparts. This pattern was not observed in the HS exercise. To conclude, JS was shown to be more connected to sprinting, COD speed and jumping abilities than HS in elite rugby sevens players and should be preferred for assessing and possibly training elite athletes needing to improve speed-power related abilities. PMID:28114431
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Orhon, Derin; Cokgor, Emine Ubay; Insel, Guclu; Karahan, Ozlem; Katipoglu, Tugce
2009-12-01
The study presented an evaluation of the effect of culture history (sludge age) on the growth kinetics of a mixed culture grown under aerobic conditions. It involved an experimental setup where a lab-scale sequencing batch reactor was operated at steady-state at two different sludge ages (theta(X)) of 2 and 10 days. The system sustained a mixed culture fed with a synthetic substrate mainly consisting of peptone. The initial concentration of substrate COD was selected around 500 mg COD/L. Polyhydroxyalkanoate (PHA) storage occurred to a limited extent, around 30 mg COD/L for theta(X)=10 days and 15 mg COD/L for theta(X)=2 days. Evaluation of the experimental data based on calibration of two different models provided consistent and reliable evidence for a variable Monod kinetics where the maximum specific growth rate, was assessed as 6.1/day for theta(X)=2 days and 4.1/day for theta(X)=10 days. A similar variability was also applicable for the hydrolysis and storage kinetics. The rate of storage was significantly lower than the levels reported in the literature, exhibiting the ability of the microorganisms to regulate their metabolic mechanisms for adjusting the rate of microbial growth and storage competing for the same substrate. This adjustment evidently resulted in case-specific, variable kinetics both for microbial growth and substrate storage.
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Oloibiri, Violet; Ufomba, Innocent; Chys, Michael; Audenaert, Wim; Demeestere, Kristof; Van Hulle, Stijn W H
2015-01-01
A major concern for landfilling facilities is the treatment of their leachate. To optimize organic matter removal from this leachate, the combination of two or more techniques is preferred in order to meet stringent effluent standards. In our study, coagulation-flocculation and ozonation are compared as pre- treatment steps for stabilized landfill leachate prior to granular activated carbon (GAC) adsorption. The efficiency of the pre treatment techniques is evaluated using COD and UVA254 measurements. For coagulation- flocculation, different chemicals are compared and optimal dosages are determined. After this, iron (III) chloride is selected for subsequent adsorption studies due to its high percentage of COD and UVA254 removal and good sludge settle-ability. Our finding show that ozonation as a single treatment is effective in reducing COD in landfill leachate by 66% compared to coagulation flocculation (33%). Meanwhile, coagulation performs better in UVA254 reduction than ozonation. Subsequent GAC adsorption of ozonated effluent, coagulated effluent and untreated leachate resulted in 77%, 53% and 8% total COD removal respectively (after 6 bed volumes). The effect of the pre-treatment techniques on GAC adsorption properties is evaluated experimentally and mathematically using Thomas and Yoon-Nelson models. Mathematical modelling of the experimental GAC adsorption data shows that ozonation increases the adsorption capacity and break through time with a factor of 2.5 compared to coagulation-flocculation.
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Loturco, Irineu; Pereira, Lucas A; Moraes, José E; Kitamura, Katia; Cal Abad, César C; Kobal, Ronaldo; Nakamura, Fábio Y
2017-01-01
The aim of this study was to evaluate the relation between the maximum mean propulsive power (MPP) obtained in the loaded jump squat (JS) and half squat (HS) exercises and functional performances in vertical jumps, 40 m linear speed (VEL) and change-of-direction (COD) tests, using the median split technique. Twenty-two male rugby sevens players from the Brazilian National Olympic Team (Rio-2016) performed vertical jumping tests (squat and countermovement jumps [SJ and CMJ]), JS and HS exercises, COD speed test and sprinting velocity in 40 m, in this order. Based on the results of the MPP in the JS and HS exercises the participants were divided, using the median split, into four groups as follows: higher JS, lower JS, higher HS, and lower HS. Between-group differences in the functional tasks were detected via magnitude-based inferences. The athletes with higher MPP in the JS were capable of jumping higher and sprinting faster (including the COD speed test) than their weaker counterparts. This pattern was not observed in the HS exercise. To conclude, JS was shown to be more connected to sprinting, COD speed and jumping abilities than HS in elite rugby sevens players and should be preferred for assessing and possibly training elite athletes needing to improve speed-power related abilities.
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Treatment of olive mill wastewater by chemical processes: effect of acid cracking pretreatment.
Hande Gursoy-Haksevenler, B; Arslan-Alaton, Idil
2014-01-01
The effect of acid cracking (pH 2.0; T 70 °C) and filtration as a pretreatment step on the chemical treatability of olive mill wastewater (chemical oxygen demand (COD) 150,000 m/L; total organic carbon (TOC) 36,000 mg/L; oil-grease 8,200 mg/L; total phenols 3,800 mg/L) was investigated. FeCl3 coagulation, Ca(OH)2 precipitation, electrocoagulation using stainless steel electrodes and the Fenton's reagent were applied as chemical treatment methods. Removal performances were examined in terms of COD, TOC, oil-grease, total phenols, colour, suspended solids and acute toxicity with the photobacterium Vibrio fischeri. Significant oil-grease (95%) and suspended solids (96%) accompanied with 58% COD, 43% TOC, 39% total phenols and 80% colour removals were obtained by acid cracking-filtration pretreatment. Among the investigated chemical treatment processes, electrocoagulation and the Fenton's reagent were found more effective after pretreatment, especially in terms of total phenols removal. Total phenols removal increased from 39 to 72% when pretreatment was applied, while no significant additional (≈10-15%) COD and TOC removals were obtained when acid cracking was coupled with chemical treatment. The acute toxicity of the original olive mill wastewater sample increased considerably after pretreatment from 75 to 89% (measured for the 10-fold diluted wastewater sample). An operating cost analysis was also performed for the selected chemical treatment processes.
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Microbial endogenous response to acute inhibitory impact of antibiotics.
Pala-Ozkok, I; Kor-Bicakci, G; Çokgör, E U; Jonas, D; Orhon, D
2017-06-13
Enhanced endogenous respiration was observed as the significant/main response of the aerobic microbial culture under pulse exposure to antibiotics: sulfamethoxazole, tetracycline and erythromycin. Peptone mixture and acetate were selected as organic substrates to compare the effect of complex and simple substrates. Experiments were conducted with microbial cultures acclimated to different sludge ages of 10 and 2 days, to visualize the effect of culture history. Evaluation relied on modeling of oxygen uptake rate profiles, reflecting the effect of all biochemical reactions associated with substrate utilization. Model calibration exhibited significant increase in values of endogenous respiration rate coefficient with all antibiotic doses. Enhancement of endogenous respiration was different with antibiotic type and initial dose. Results showed that both peptone mixture and acetate cultures harbored resistance genes against the tested antibiotics, which suggests that biomass spends cellular maintenance energy for activating the required antibiotic resistance mechanisms to survive, supporting higher endogenous decay rates. [Formula: see text]: maximum growth rate for X H (day -1 ); K S : half saturation constant for growth of X H (mg COD/L); b H : endogenous decay rate for X H (day -1 ); k h : maximum hydrolysis rate for S H1 (day -1 ); K X : hydrolysis half saturation constant for S H1 (mg COD/L); k hx : maximum hydrolysis rate for X S1 (day -1 ); K XX : hydrolysis half saturation constant for X S1 (mg COD/L); k STO : maximum storage rate of PHA by X H (day -1 ); [Formula: see text]: maximum growth rate on PHA for X H (day -1 ); K STO : half saturation constant for storage of PHA by X H (mg COD/L); X H1 : initial active biomass (mg COD/L).
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Kinetics and methane gas yields of selected C1 to C5 organic acids in anaerobic digestion.
Yang, Yu; Chen, Qian; Guo, Jialiang; Hu, Zhiqiang
2015-12-15
Volatile fatty acids (VFAs) and other short-chain organic acids such as lactic and pyruvic acids are intermediates in anaerobic organic degradation. In this study, anaerobic degradation of seven organic acids in salt form was investigated, including formate (C1), acetate (C2), propionate (C3), pyruvate (C3), lactate (C3), butyrate (C4), and valerate (C5). Microbial growth kinetics on these organic acids were determined individually at 37 °C through batch anaerobic digestion tests by varying substrate concentrations from 250 to 4000 mg COD/L. The cumulative methane generation volume was determined real-time by respirometry coupled with gas chromatographic analysis while methane yield and related kinetics were calculated. The methane gas yields (fe, mg CH4 COD/mg substrate COD) from anaerobic degradation of formate, acetate, propionate, pyruvate, lactate, butyrate, and valerate were 0.44 ± 0.27, 0.58 ± 0.05, 0.53 ± 0.18, 0.24 ± 0.05, 0.17 ± 0.05, 0.43 ± 0.15, 0.49 ± 0.11, respectively. Anaerobic degradation of formate showed self-substrate inhibition at the concentrations above 3250 mg COD/L. Acetate, propionate, pyruvate, butyrate, lactate, and valerate did not inhibit methane production at the highest concentrations tested (i.e., 4000 mg COD/L). Microbes growing on acetate had the highest overall specific growth rate (0.30 d(-1)) in methane production. For comparison, the specific microbial growth rates on formate, propionate, pyruvate, butyrate, lactate, and valerate for methane production were 0.10, 0.06, 0.08, 0.07, 0.05, 0.15 d(-1), respectively. Copyright © 2015 Elsevier Ltd. All rights reserved.
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Jung, Chanil; Deng, Yang; Zhao, Renzun; Torrens, Kevin
2017-01-01
UV-quenching substance (UVQS), as an emerging municipal solid waste (MSW)-derived leachate contaminant, has a potential to interfere with UV disinfection when leachate is disposed of at publicly owned treatment works (POTWs). The objective of this study was to evaluate and compare two chemical oxidation processes under different operational conditions, i.e. Fenton process and ozonation, for alleviation of UV 254 absorbance of a biologically pre-treated landfill leachate. Results showed that leachate UV 254 absorbance was reduced due to the UVQS decomposition by hydroxyl radicals (·OH) during Fenton treatment, or by ozone (O 3 ) and ·OH during ozonation. Fenton process exhibited a better treatment performance than ozonation under their respective optimal conditions, because ·OH could effectively decompose both hydrophobic and hydrophilic dissolved organic matter (DOM), but O 3 tended to selectively oxidize hydrophobic compounds alone. Different analytical techniques, including molecular weight (MW) fractionation, hydrophobic/hydrophilic isolation, UV spectra scanning, parallel factor (PARAFAC) analysis, and fluorescence excitation-emission matrix spectrophotometry, were used to characterize UVQS. After either oxidation treatment, residual UVQS was more hydrophilic with a higher fraction of low MW molecules. It should be noted that the removed UV 254 absorbance (ΔUV 254 ) was directly proportional to the removed COD (ΔCOD) for the both treatments (Fenton process: ΔUV 254 = 0.011ΔCOD; ozonation: ΔUV 254 = 0.016ΔCOD). A greater ΔUV 254 /ΔCOD was observed for ozonation, suggesting that oxidant was more efficiently utilized during ozonation than in Fenton treatment for mitigation of the UV absorbance. Copyright © 2016 Elsevier Ltd. All rights reserved.
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Multidimensionality of behavioural phenotypes in Atlantic cod, Gadus morhua.
Meager, Justin J; Fernö, Anders; Skjæraasen, Jon Egil; Järvi, Torbjörn; Rodewald, Petra; Sverdrup, Gisle; Winberg, Svante; Mayer, Ian
2012-06-25
Much of the inter-individual variation observed in animal behaviour is now attributed to the existence of behavioural phenotypes or animal personalities. Such phenotypes may be fundamental to fisheries and aquaculture, yet there have been few detailed studies of this phenomenon in exploited marine animals. We investigated the behavioural and neuroendocrine responses of Atlantic cod (Gadus morhua L.), to situations reflecting critical ecological challenges: predator attacks and territorial challenges. Both hatchery-reared and wild fish were tested and behavioural profiles were compared with baseline conditions. We then used an objective, multivariate approach, rather than assigning individuals along one-dimensional behavioural axes, to examine whether distinct behavioural phenotypes were present. Our results indicate that two distinct behavioural phenotypes were evident in fish from each background. In hatchery-reared fish, phenotypes displayed divergent locomotor activity, sheltering, brain monoamine concentrations and responses to competitive challenges. In wild fish, phenotypes were distinguished primarily by locomotor activity, sheltering and responsiveness to predator stimuli. Hatcheries presumably represent a more stressful social environment, and social behaviour and neuroendocrine responses were important in discerning behavioural phenotypes in hatchery fish, whereas antipredator responses were important in discerning phenotypes in wild fish that have previously encountered predators. In both fish types, behavioural and physiological traits that classified individuals into phenotypes were not the same as those that were correlated across situations. These results highlight the multidimensionality of animal personalities, and that the processes that regulate one suite of behavioural traits may be very different to the processes that regulate other behaviours. Copyright © 2012 Elsevier Inc. All rights reserved.
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Aguilera, Stacy E.; Cole, Jennifer; Finkbeiner, Elena M.; Le Cornu, Elodie; Ban, Natalie C.; Carr, Mark H.; Cinner, Joshua E.; Crowder, Larry B.; Gelcich, Stefan; Hicks, Christina C.; Kittinger, John N.; Martone, Rebecca; Malone, Daniel; Pomeroy, Carrie; Starr, Richard M.; Seram, Sanah; Zuercher, Rachel; Broad, Kenneth
2015-01-01
Globally, small-scale fisheries are influenced by dynamic climate, governance, and market drivers, which present social and ecological challenges and opportunities. It is difficult to manage fisheries adaptively for fluctuating drivers, except to allow participants to shift effort among multiple fisheries. Adapting to changing conditions allows small-scale fishery participants to survive economic and environmental disturbances and benefit from optimal conditions. This study explores the relative influence of large-scale drivers on shifts in effort and outcomes among three closely linked fisheries in Monterey Bay since the Magnuson-Stevens Fisheries Conservation and Management Act of 1976. In this region, Pacific sardine (Sardinops sagax), northern anchovy (Engraulis mordax), and market squid (Loligo opalescens) fisheries comprise a tightly linked system where shifting focus among fisheries is a key element to adaptive capacity and reduced social and ecological vulnerability. Using a cluster analysis of landings, we identify four modes from 1974 to 2012 that are dominated (i.e., a given species accounting for the plurality of landings) by squid, sardine, anchovy, or lack any dominance, and seven points of transition among these periods. This approach enables us to determine which drivers are associated with each mode and each transition. Overall, we show that market and climate drivers are predominantly attributed to dominance transitions. Model selection of external drivers indicates that governance phases, reflected as perceived abundance, dictate long-term outcomes. Our findings suggest that globally, small-scale fishery managers should consider enabling shifts in effort among fisheries and retaining existing flexibility, as adaptive capacity is a critical determinant for social and ecological resilience. PMID:25790464
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Galuardi, Benjamin; Lutcavage, Molly
2012-01-01
Between 2005 and 2009, we deployed 58 miniature pop-up satellite archival tags (PSAT) and 132 implanted archival tags on juvenile Atlantic bluefin tuna (age 2–5) in the northwest Atlantic Ocean. Data returned from these efforts (n = 26 PSATs, 1 archival tag) revealed their dispersal routes, horizontal and vertical movements and habitat utilization. All of the tagged bluefin tuna remained in the northwest Atlantic for the duration observed, and in summer months exhibited core-use of coastal seas extending from Maryland to Cape Cod, MA, (USA) out to the shelf break. Their winter distributions were more spatially disaggregated, ranging south to the South Atlantic Bight, northern Bahamas and Gulf Stream. Vertical habitat patterns showed that juvenile bluefin tuna mainly occupied shallow depths (mean = 5–12 m, sd = 15–23.7 m) and relatively warm water masses in summer (mean = 17.9–20.9°C, sd = 4.2–2.6°C) and had deeper and more variable depth patterns in winter (mean = 41–58 m, sd = 48.9–62.2 m). Our tagging results reveal annual dispersal patterns, behavior and oceanographic associations of juvenile Atlantic bluefin tuna that were only surmised in earlier studies. Fishery independent profiling from electronic tagging also provide spatially and temporally explicit information for evaluating dispersals rates, population structure and fisheries catch patterns. PMID:22629461
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Tirado-Ibarra, Jorge de Jesus; Loya-Rodriguez, Mariany; Morales-Arevalo, Jose Carlos; Muñoz-Garcia, Isabel Rosario; Martinez-Perez, Francisco; Ramirez-Perez, Jorge Saul; Jimenez-Gutierrez, Laura Rebeca
2018-01-01
The shrimp fishery is one of the most important fisheries in the world, although the low selectivity from trawling nets has led to the capture of a large number of non-target species. Shrimp-bycatch species include a large number of fish and invertebrate species, of which fish species are the most abundant. The present study aims to determine the community structure as well as the average sizes at first maturity of the fish species from shrimp-bycatch caught from industrial fisheries in the Mexican Pacific from Sinaloa to Guerrero, from January to March 2015. The shrimp-bycatch fish diversity value was found to be 2.22. A total of 37 species of finfish were found, of which five were considered rare. The fish species with the highest Importance Value Index (IVI) levels were Pseudupeneus grandisquamis , Paralichthys woolmani , Lutjanus peru and Diapterus peruvianus . The average size at first maturity was calculated for all species. Of the analysed organisms, 90% were in the juvenile stage, including species with riverine and artisanal fisheries. The present study demonstrates the risk within marine populations to different non-target species due to the poor selectivity of shrimp trawls.
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Seafood Wars: Reviving a Tired Sustainability Education Program with Pop Culture Techniques
NASA Astrophysics Data System (ADS)
Peart, L. W.
2016-02-01
Texas State Aquarium revived its sustainable seafood education program by embedding expert speakers into the pop culture chef competition. Chefs are nominated by diners and vetted by Aquarium staff. Seafood selections are made in consultation with fishery experts and sustainability partners including Gulf United for Lasting Fisheries. Through these efforts, the Seafood Wars audience has expanded from the over-40 set to college and graduate students, families, and adults of all ages. Surveyed participants at these sell-out events are 100% as, or more likely to purchase and consume featured sustainable selections.
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NASA Astrophysics Data System (ADS)
KIM, M.; Kim, J.; Baek, J.; Kim, C.; Shin, H.
2013-12-01
It has being happened as flush flood or red/green tide in various natural phenomena due to climate change and indiscreet development of river or land. Especially, water being very important to man should be protected and managed from water quality pollution, and in water resources management, real-time watershed monitoring system is being operated with the purpose of keeping watch and managing on rivers. It is especially important to monitor and forecast water quality in watershed. A study area selected Nak_K as one site among TMDL unit watershed in Nakdong River. This study is to develop a water quality forecasting model connected with making full use of observed data of 8 day interval from Nakdong River Environment Research Center. When forecasting models for each of the BOD, DO, COD, and chlorophyll-a are established considering correlation of various water quality factors, it is needed to select water quality factors showing highly considerable correlation with each water quality factor which is BOD, DO, COD, and chlorophyll-a. For analyzing the correlation of the factors (reservoir discharge, precipitation, air temperature, DO, BOD, COD, Tw, TN, TP, chlorophyll-a), in this study, self-organizing map was used and cross correlation analysis method was also used for comparing results drawn. Based on the results, each forecasting model for BOD, DO, COD, and chlorophyll-a was developed during the short period as 8, 16, 24, 32 days at 8 day interval. The each forecasting model is based on neural network with back propagation algorithm. That is, the study is connected with self-organizing map for analyzing correlation among various factors and neural network model for forecasting of water quality. It is considerably effective to manage the water quality in plenty of rivers, then, it specially is possible to monitor a variety of accidents in water quality. It will work well to protect water quality and to prevent destruction of the environment becoming more and more serious before occurring.
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Armstrong, M J; Payne, A I L; Deas, B; Catchpole, T L
2013-10-01
Following from similar initiatives worldwide, the U.K.'s Fisheries Science Partnership (FSP) was established in 2003 to provide the fishing industry with opportunities to propose and participate in scientific studies in collaboration with fishery scientists. Key concepts were that most of the available funding would support industry participation, that industry, not scientists, would come up with the ideas for projects, and that commercial fishing vessels and fishing methods would be used to address specific concerns of the fishing industry in a scientifically controlled manner. Nearly 100 projects had been commissioned by March 2012, covering annual time-series surveys of stocks subject to traditional assessment, and ad hoc projects on, e.g. gear selectivity, discard survival, tagging and migration and fishery development. The extent to which the results of the projects have been used by stakeholders, fishery scientists and fishery managers at a national and E.U. level is evaluated, along with the degree of industry interest and involvement, and reasons are identified for successes or failures in the uptake of the results into management and policy. Finally, the question is posed whether the programme has been successful in improving the engagement of the fishing community in the science-management process and in fostering communication and greater trust between fishers, scientists and managers. © 2013 Crown Copyright. © 2013 The Fisheries Society of the British Isles.
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Heylen, Elisabeth; Batoko Likele, Bibi; Zeller, Mark; Stevens, Stijn; De Coster, Sarah; Conceição-Neto, Nádia; Van Geet, Christel; Jacobs, Jan; Ngbonda, Dauly; Van Ranst, Marc; Matthijnssens, Jelle
2014-01-01
Group A rotavirus (RVA) infections form a major public health problem, especially in low-income countries like the Democratic Republic of the Congo (COD). However, limited data on RVA diversity is available from sub-Saharan Africa in general and the COD in particular. Therefore, the first aim of this study was to determine the genetic diversity of 99 RVAs detected during 2007–2010 in Kisangani, COD. The predominant G-type was G1 (39%) and the most predominant P-type was P[6] (53%). A total of eight different G/P-combinations were found: G1P[8] (28%), G8P[6] (26%), G2P[4] (14%), G12P[6] (13%), G1P[6] (11%), G9P[8] (4%), G4P[6] (2%) and G8P[4] (1%). The second aim of this study was to gain insight into the diversity of P[6] RVA strains in the COD. Therefore, we selected five P[6] RVA strains in combination with the G1, G4, G8 (2x) or G12 genotype for complete genome analysis. Complete genome analysis showed that the genetic background of the G1P[6] and G12P[6] strains was entirely composed of genotype 1 (Wa-like), while the segments of the two G8P[6] strains were identified as genotype 2 (DS-1-like). Interestingly, all four strains possessed a NSP4 gene of animal origin. The analyzed G4P[6] RVA strain was found to possess the unusual G4-P[6]-I1-R1-C1-M1-A1-N1-T7-E1-H1 constellation. Although the majority of its genes (if not all), were presumably of porcine origin, this strain was able to cause gastro-enteritis in humans. The high prevalence of unusual RVA strains in the COD highlights the need for continued surveillance of RVA diversity in the COD. These results also underline the importance of complete genetic characterization of RVA strains and indicate that reassortments and interspecies transmission among human and animal RVAs strains occur regularly. Based on these data, RVA vaccines will be challenged with a wide variety of different RVA strain types in the COD. PMID:24968018
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NASA Astrophysics Data System (ADS)
Hahlbeck, N.; Scales, K. L.; Hazen, E. L.; Bograd, S. J.
2016-12-01
The reduction of bycatch, or incidental capture of non-target species in a fishery, is a key objective of ecosystem-based fisheries management (EBFM) and critical to the conservation of many threatened marine species. Prediction of bycatch events is therefore of great importance to EBFM efforts. Here, bycatch of the ocean sunfish (Mola mola) and bluefin tuna (Thunnus thynnus) in the California drift gillnet fishery is modeled using a suite of remotely sensed environmental variables as predictors. Data from 8321 gillnet sets was aggregated by month to reduce zero inflation and autocorrelation among sets, and a set of a priori generalized additive models (GAMs) was created for each species based on literature review and preliminary data exploration. Each of the models was fit using a binomial family with a logit link in R, and Aikake's Information Criterion with correction (AICc) was used in the first stage of model selection. K-fold cross validation was used in the second stage of model selection and performance assessment, using the least-squares linear model of predicted vs. observed values as the performance metric. The best-performing mola model indicated a strong, nearly linear negative correlation with sea surface temperature, as well as weaker nonlinear correlations with eddy kinetic energy, chlorophyll-a concentration and rugosity. These findings are consistent with current understanding of ocean sunfish habitat use; for example, previous studies suggest seasonal movement patterns and exploitation of dynamic, highly productive areas characteristic of upwelling regions. Preliminary results from the bluefin models also indicate seasonal fluctuation and correlation with environmental variables. These models can be used with near-real time satellite data as bycatch avoidance tools for both fishers and managers, allowing for the use of more dynamic ocean management strategies to improve sustainability of the fishery.
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NASA Astrophysics Data System (ADS)
Hahlbeck, N.; Scales, K. L.; Hazen, E. L.; Bograd, S. J.
2016-02-01
The reduction of bycatch, or incidental capture of non-target species in a fishery, is a key objective of ecosystem-based fisheries management (EBFM) and critical to the conservation of many threatened marine species. Prediction of bycatch events is therefore of great importance to EBFM efforts. Here, bycatch of the ocean sunfish (Mola mola) and bluefin tuna (Thunnus thynnus) in the California drift gillnet fishery is modeled using a suite of remotely sensed environmental variables as predictors. Data from 8321 gillnet sets was aggregated by month to reduce zero inflation and autocorrelation among sets, and a set of a priori generalized additive models (GAMs) was created for each species based on literature review and preliminary data exploration. Each of the models was fit using a binomial family with a logit link in R, and Aikake's Information Criterion with correction (AICc) was used in the first stage of model selection. K-fold cross validation was used in the second stage of model selection and performance assessment, using the least-squares linear model of predicted vs. observed values as the performance metric. The best-performing mola model indicated a strong, nearly linear negative correlation with sea surface temperature, as well as weaker nonlinear correlations with eddy kinetic energy, chlorophyll-a concentration and rugosity. These findings are consistent with current understanding of ocean sunfish habitat use; for example, previous studies suggest seasonal movement patterns and exploitation of dynamic, highly productive areas characteristic of upwelling regions. Preliminary results from the bluefin models also indicate seasonal fluctuation and correlation with environmental variables. These models can be used with near-real time satellite data as bycatch avoidance tools for both fishers and managers, allowing for the use of more dynamic ocean management strategies to improve sustainability of the fishery.
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Recreational fishing selectively captures individuals with the highest fitness potential
Sutter, David A. H.; Suski, Cory D.; Philipp, David P.; Klefoth, Thomas; Wahl, David H.; Kersten, Petra; Cooke, Steven J.; Arlinghaus, Robert
2012-01-01
Fisheries-induced evolution and its impact on the productivity of exploited fish stocks remains a highly contested research topic in applied fish evolution and fisheries science. Although many quantitative models assume that larger, more fecund fish are preferentially removed by fishing, there is no empirical evidence describing the relationship between vulnerability to capture and individual reproductive fitness in the wild. Using males from two lines of largemouth bass (Micropterus salmoides) selectively bred over three generations for either high (HV) or low (LV) vulnerability to angling as a model system, we show that the trait “vulnerability to angling” positively correlates with aggression, intensity of parental care, and reproductive fitness. The difference in reproductive fitness between HV and LV fish was particularly evident among larger males, which are also the preferred mating partners of females. Our study constitutes experimental evidence that recreational angling selectively captures individuals with the highest potential for reproductive fitness. Our study further suggests that selective removal of the fittest individuals likely occurs in many fisheries that target species engaged in parental care. As a result, depending on the ecological context, angling-induced selection may have negative consequences for recruitment within wild populations of largemouth bass and possibly other exploited species in which behavioral patterns that determine fitness, such as aggression or parental care, also affect their vulnerability to fishing gear. PMID:23213220
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Recreational fishing selectively captures individuals with the highest fitness potential.
Sutter, David A H; Suski, Cory D; Philipp, David P; Klefoth, Thomas; Wahl, David H; Kersten, Petra; Cooke, Steven J; Arlinghaus, Robert
2012-12-18
Fisheries-induced evolution and its impact on the productivity of exploited fish stocks remains a highly contested research topic in applied fish evolution and fisheries science. Although many quantitative models assume that larger, more fecund fish are preferentially removed by fishing, there is no empirical evidence describing the relationship between vulnerability to capture and individual reproductive fitness in the wild. Using males from two lines of largemouth bass (Micropterus salmoides) selectively bred over three generations for either high (HV) or low (LV) vulnerability to angling as a model system, we show that the trait "vulnerability to angling" positively correlates with aggression, intensity of parental care, and reproductive fitness. The difference in reproductive fitness between HV and LV fish was particularly evident among larger males, which are also the preferred mating partners of females. Our study constitutes experimental evidence that recreational angling selectively captures individuals with the highest potential for reproductive fitness. Our study further suggests that selective removal of the fittest individuals likely occurs in many fisheries that target species engaged in parental care. As a result, depending on the ecological context, angling-induced selection may have negative consequences for recruitment within wild populations of largemouth bass and possibly other exploited species in which behavioral patterns that determine fitness, such as aggression or parental care, also affect their vulnerability to fishing gear.
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50 CFR 85.31 - Grant selection.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 50 Wildlife and Fisheries 6 2010-10-01 2010-10-01 false Grant selection. 85.31 Section 85.31...) FINANCIAL ASSISTANCE-WILDLIFE SPORT FISH RESTORATION PROGRAM CLEAN VESSEL ACT GRANT PROGRAM Grant Selection § 85.31 Grant selection. The Fish and Wildlife Service, Division of Federal Aid, will convene a ranking...
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Cooke, Steven J; Donaldson, Michael R; Hinch, Scott G; Crossin, Glenn T; Patterson, David A; Hanson, Kyle C; English, Karl K; Shrimpton, J Mark; Farrell, Anthony P
2009-01-01
There is extensive evidence that fishing is often selective for specific phenotypic characteristics, and that selective harvest can thus result in genotypic change. To date, however, there are no studies that evaluate whether fishing is selective for certain physiological or energetic characteristics that may influence fish behaviour and thus vulnerability to capture. Here, adult sockeye salmon (Oncorhynchus nerka) were used as a model to test the null hypothesis that fishing is not selective for specific physiological or energetic traits. Fish were intercepted during their spawning migrations, implanted with a gastric radio transmitter, and biopsied (i.e., non-lethally sampled for blood, gill tissue and quantification of energetic status). In both 2003 and 2006, we tagged and biopsied 301 and 770 sockeye salmon, respectively, in the marine environment en route to their natal river system to spawn. In 2006 an additional 378 individuals were tagged and biopsied in freshwater. We found that 23 (7.6%) of the marine fish tagged in 2003, 78 (10.1%) of the marine fish tagged in 2006 and 57 (15.1%) of the freshwater fish tagged in 2006 were harvested by one of three fisheries sectors that operate in the coastal marine environment and the Fraser River (i.e. commercial, recreational or First Nations fisheries between the site of release and Hell's Gate in the Fraser River, approximately 250 km upriver and 465 km from the ocean tagging site). However, fisheries were not open continually or consistently in different locations and for different fisheries sectors necessitating a paired analytical approach. As such, for statistical analyses we paired individual fish that were harvested with another fish of the same genetic stock that was released on the same date and exhibited similar migration behaviour, except that they successfully evaded capture and reached natal spawning grounds. Using two-tailed Wilcoxon matched pairs signed-rank tests, we revealed that the physiological and energetic characteristics of harvested fish did not differ from those of the successful migrants despite evaluating a number of biochemical (e.g. plasma metabolites, cortisol, plasma ions, gill Na+/K+-ATPase) and energetic (e.g. gross somatic energy density) variables (P's all >0.10). However, for some analyses we suffered low statistical power and the study design had several shortcomings that could have made detection of differences difficult. We suggest that additional research explore the concept of fishing-induced selection for physiological characteristics because physiology is closely linked to three traits where fisheries-induced selection does occur (i.e. life-history, behaviour and morphology). PMID:25567882
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Effect of White Charcoal on COD Reduction in Wastewater Treatment
NASA Astrophysics Data System (ADS)
Pijarn, Nuchanaporn; Butsee, Manipa; Buakul, Kanokwan; Seng, Hasan; Sribuarai, Tinnphat; Phonprasert, Pongtep; Taneeto, Kla; Atthameth, Prasertsil
2017-06-01
The objective of this study is to compare the COD reduction in wastewater between using coconut shell and coconut spathe white charcoal from Khlong Wat NongPra-Ong, Krathumbaen, SamutSakhon province, Thailand. The waste water samples were collected using composite sampling method. The experimental section can be divided into 2 parts. The first part was study the optimum of COD adsorption time using both white charcoals. The second part was study the optimum amount of white charcoal for chemical oxygen demand (COD) reduction. The pre-treatment of wastewater was examined in parameters include temperature, alkalinity (pH), conductivity, turbidity, suspended solid (SS), total dissolved solid (TDS), and COD. The results show that both white charcoals can reduce COD of wastewater. The pH of pre-treatment wastewater had pH 9 but post-treatment wastewaters using both white charcoals have pH 8. The COD of pre-treatment wastewater had COD as 258 mg/L but post-treatment wastewater using coconut shell white charcoal had COD steady at 40 mg/L in 30 min and the amount of white charcoals 4 g. The COD of post-treatment wastewater using coconut spathe white charcoal had COD steady at 71 mg/L in 30 min and the amount of white charcoals 4 g. Therefore comparison of COD reduction between coconut shell white charcoal versus coconut spathe white charcoal found that the coconut shell white charcoal had efficiency for COD reduction better than coconut spathe white charcoal.
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A behavioral perspective on fishing-induced evolution.
Uusi-Heikkilä, Silva; Wolter, Christian; Klefoth, Thomas; Arlinghaus, Robert
2008-08-01
The potential for excessive and/or selective fishing to act as an evolutionary force has been emphasized recently. However, most studies have focused on evolution of life-history traits in response to size-selective harvesting. Here we draw attention to fishing-induced evolution of behavioral and underlying physiological traits. We contend that fishing-induced selection directly acting on behavioral rather than on life-history traits per se can be expected in all fisheries that operate with passive gears such as trapping, angling and gill-netting. Recent artificial selection experiments in the nest-guarding largemouth bass Micropterus salmoides suggest that fishing-induced evolution of behavioral traits that reduce exposure to fishing gear might be maladaptive, potentially reducing natural recruitment. To improve understanding and management of fisheries-induced evolution, we encourage greater application of methods from behavioral ecology, physiological ecology and behavioral genetics.
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Federal Register 2010, 2011, 2012, 2013, 2014
2011-11-14
... based on its preferred level of risk aversion. The ABC is based on a percentage reduction of the OFL as determined by an SSC determination on scientific uncertainty and a risk policy determined by the Council. In... Council then selects a level of risk aversion by choosing an appropriate P* value. Each P* value is then...
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Zagatto, Alessandro M; Ardigò, Luca P; Barbieri, Fabio A; Milioni, Fabio; Dello Iacono, Antonio; Camargo, Bruno H F; Padulo, Johnny
2017-09-01
Zagatto, AM, Ardigò, LP, Barbieri, FA, Milioni, F, Dello Iacono, A, Camargo, BHF, and Padulo, J. Performance and metabolic demand of a new repeated-sprint ability test in basketball players: does the number of changes of direction matter? J Strength Cond Res 31(9): 2438-2446, 2017-This study compared 2 repeated-sprint ability (RSA) tests in basketball players. Both tests included 10 × 30-m sprints, with the difference that the previously validated test (RSA2COD) featured 2 changes of direction (COD) per sprint, whereas the experimental test (RSA5COD) featured 5 CODs per sprint. Test performances and metabolic demands were specifically assessed in 20 basketball players. First, RSA5COD test-retest reliability was investigated. Then, RSA2COD, RSA5COD sprint times, peak speeds, oxygen uptake (V[Combining Dot Above]O2) and posttest blood lactate concentration [La] were measured. The RSA5COD results showed to be reliable. RSA2COD performance resulted better than the RSA5COD version (p < 0.01), with shorter sprint times and higher peak speeds. Over sprints, the tests did not differ from each other in terms of V[Combining Dot Above]O2 (p > 0.05). Over whole bout, the RSA2COD was more demanding than the RSA5COD, considering overall metabolic power requirement (i.e., VO2-driven + [La]-driven components). Given that RSA5COD (a) mimics real game-play as sprint distance and action change frequency/direction and (b) has the same metabolic expenditure per task completion as metabolic cost, RSA5COD is a valuable option for players and coaches for training basketball-specific agility and assessing bioenergetic demands.
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The CodY regulator is essential for virulence in Streptococcus suis serotype 2
Feng, Liping; Zhu, Jiawen; Chang, Haitao; Gao, Xiaoping; Gao, Cheng; Wei, Xiaofeng; Yuan, Fangyan; Bei, Weicheng
2016-01-01
The main role of CodY, a global regulatory protein in most low G + C gram-positive bacteria, is in transcriptional repression. To study the functions of CodY in Streptococcus suis serotype 2 (S. suis 2), a mutant codY clone named ∆codY was constructed to explore the phenotypic variation between ∆codY and the wild-type strain. The result showed that the codY mutation significantly inhibited cell growth, adherence and invasion ability of S. suis 2 to HEp-2 cells. The codY mutation led to decreased binding of the pathogen to the host cells, easier clearance by RAW264.7 macrophages and decreased growth ability in fresh blood of Cavia porcellus. The codY mutation also attenuated the virulence of S. suis 2 in BALB/c mice. Morphological analysis revealed that the codY mutation decreased the thickness of the capsule of S. suis 2 and changed the surface structures analylized by SDS-PAGE. Finally, the codY mutation altered the expressions of many virulence related genes, including sialic acid synthesis genes, leading to a decreased sialic acid content in capsule. Overall, mutation of codY modulated bacterial virulence by affecting the growth and colonization of S. suis 2, and at least via regulating sialic acid synthesis and capsule thickness. PMID:26883762
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Federal Register 2010, 2011, 2012, 2013, 2014
2012-04-16
... DEPARTMENT OF THE INTERIOR National Park Service [1730-SZM] Cape Cod National Seashore Advisory Commission; Cape Cod National Seashore, South Wellfleet, MA AGENCY: National Park Service, Interior. ACTION... Cod National Seashore, 99 Marconi Site Road, Wellfleet, MA 02667. Dated: April 9, 2012. George E...
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Anaerobic treatment of landfill leachate by sulfate reduction.
Henry, J G; Prasad, D
2000-01-01
The present study was conducted to investigate the effectiveness of the sulphate-reduction pathway in the anaerobic treatment of landfill leachate. The effects of several COD/SO4 ratios (keeping COD constant) and loadings on anaerobic filter performance were studied and compared with the results from anaerobic filters which followed the methanogenic pathway. Results indicated that the treatability of leachate by sulphate reducing bacteria (SRB) was dependent upon the leachate strength. With high strength leachate (COD = 15,000 mg/L) from the Keele Valley Landfill, it was found that at lower COD/SO4 ratios (< or = 1.6) toxic conditions developed in the system that were more inhibitory to the SRB than to the methane producing bacteria (MPB). As the COD/SO4 ratio increased, methanogenesis predominated. No predominance of SRB occurred at any COD/SO4 ratio with high strength leachate. The highest COD removal achieved was about 70% of which 20% was accomplished by the SRB at a COD/SO4 ratio of 1.6 and an organic loading rate (OLR) of 4 kg COD/m3.d. With low strength leachate (COD = 1500-3300 mg/L) from the Brock West Landfill, and a COD/SO4 ratio < or = 1, SRB became predominant. In these anaerobic filters in which SRB were predominant, the SRB reduced the COD as well as the MPB could. Sulphide inhibition did not take place at any loading in units treating low strength leachate. Consequently, both SRB and MPB should function at COD/SO4 ratios between 1 and 3. About 60% COD removal was achieved at a loading of 2.8 kg COD/m3.d and a COD/SO4 ratio of 1.0. However at a loading of 6 kg COD/m3.d only 27% COD removal was achieved, all of it through the sulphate-reduction pathway. These OLR values are comparable to those applied in systems where methanogenesis was dominant. It was also observed that once the methanogens were established in the units, it was not possible to displace them completely. However, where methanogenesis had not been previously established, it was found that sulphate-reduction could be the sole pathway for COD removal. From this study, it can be concluded that there is no advantage to the sulphate-reduction pathway in the anaerobic treatment of landfill leachate. The other options for increasing the loadings, i.e. the use of high surface/volume filter media (to achieve higher biomass concentrations) or high rate systems are likely to be more successful.
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COD::CIF::Parser: an error-correcting CIF parser for the Perl language.
Merkys, Andrius; Vaitkus, Antanas; Butkus, Justas; Okulič-Kazarinas, Mykolas; Kairys, Visvaldas; Gražulis, Saulius
2016-02-01
A syntax-correcting CIF parser, COD::CIF::Parser , is presented that can parse CIF 1.1 files and accurately report the position and the nature of the discovered syntactic problems. In addition, the parser is able to automatically fix the most common and the most obvious syntactic deficiencies of the input files. Bindings for Perl, C and Python programming environments are available. Based on COD::CIF::Parser , the cod-tools package for manipulating the CIFs in the Crystallography Open Database (COD) has been developed. The cod-tools package has been successfully used for continuous updates of the data in the automated COD data deposition pipeline, and to check the validity of COD data against the IUCr data validation guidelines. The performance, capabilities and applications of different parsers are compared.
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CodY-Dependent Regulation of Sporulation in Clostridium difficile.
Nawrocki, Kathryn L; Edwards, Adrianne N; Daou, Nadine; Bouillaut, Laurent; McBride, Shonna M
2016-08-01
Clostridium difficile must form a spore to survive outside the gastrointestinal tract. The factors that trigger sporulation in C. difficile remain poorly understood. Previous studies have suggested that a link exists between nutritional status and sporulation initiation in C. difficile In this study, we investigated the impact of the global nutritional regulator CodY on sporulation in C. difficile strains from the historical 012 ribotype and the current epidemic 027 ribotype. Sporulation frequencies were increased in both backgrounds, demonstrating that CodY represses sporulation in C. difficile The 027 codY mutant exhibited a greater increase in spore formation than the 012 codY mutant. To determine the role of CodY in the observed sporulation phenotypes, we examined several factors that are known to influence sporulation in C. difficile Using transcriptional reporter fusions and quantitative reverse transcription-PCR (qRT-PCR) analysis, we found that two loci associated with the initiation of sporulation, opp and sinR, are regulated by CodY. The data demonstrate that CodY is a repressor of sporulation in C. difficile and that the impact of CodY on sporulation and expression of specific genes is significantly influenced by the strain background. These results suggest that the variability of CodY-dependent regulation is an important contributor to virulence and sporulation in current epidemic isolates. This report provides further evidence that nutritional state, virulence, and sporulation are linked in C. difficile This study sought to examine the relationship between nutrition and sporulation in C. difficile by examining the global nutritional regulator CodY. CodY is a known virulence and nutritional regulator of C. difficile, but its role in sporulation was unknown. Here, we demonstrate that CodY is a negative regulator of sporulation in two different ribotypes of C. difficile We also demonstrate that CodY regulates known effectors of sporulation, Opp and SinR. These results support the idea that nutrient limitation is a trigger for sporulation in C. difficile and that the response to nutrient limitation is coordinated by CodY. Additionally, we demonstrate that CodY has an altered role in sporulation regulation for some strains. Copyright © 2016, American Society for Microbiology. All Rights Reserved.
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CodY-Dependent Regulation of Sporulation in Clostridium difficile
Nawrocki, Kathryn L.; Edwards, Adrianne N.; Daou, Nadine; Bouillaut, Laurent
2016-01-01
ABSTRACT Clostridium difficile must form a spore to survive outside the gastrointestinal tract. The factors that trigger sporulation in C. difficile remain poorly understood. Previous studies have suggested that a link exists between nutritional status and sporulation initiation in C. difficile. In this study, we investigated the impact of the global nutritional regulator CodY on sporulation in C. difficile strains from the historical 012 ribotype and the current epidemic 027 ribotype. Sporulation frequencies were increased in both backgrounds, demonstrating that CodY represses sporulation in C. difficile. The 027 codY mutant exhibited a greater increase in spore formation than the 012 codY mutant. To determine the role of CodY in the observed sporulation phenotypes, we examined several factors that are known to influence sporulation in C. difficile. Using transcriptional reporter fusions and quantitative reverse transcription-PCR (qRT-PCR) analysis, we found that two loci associated with the initiation of sporulation, opp and sinR, are regulated by CodY. The data demonstrate that CodY is a repressor of sporulation in C. difficile and that the impact of CodY on sporulation and expression of specific genes is significantly influenced by the strain background. These results suggest that the variability of CodY-dependent regulation is an important contributor to virulence and sporulation in current epidemic isolates. This report provides further evidence that nutritional state, virulence, and sporulation are linked in C. difficile. IMPORTANCE This study sought to examine the relationship between nutrition and sporulation in C. difficile by examining the global nutritional regulator CodY. CodY is a known virulence and nutritional regulator of C. difficile, but its role in sporulation was unknown. Here, we demonstrate that CodY is a negative regulator of sporulation in two different ribotypes of C. difficile. We also demonstrate that CodY regulates known effectors of sporulation, Opp and SinR. These results support the idea that nutrient limitation is a trigger for sporulation in C. difficile and that the response to nutrient limitation is coordinated by CodY. Additionally, we demonstrate that CodY has an altered role in sporulation regulation for some strains. PMID:27246573
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Dubber, Donata; Gray, Nicholas F
2010-10-01
Chemical oxygen demand (COD) is widely used for wastewater monitoring, design, modeling and plant operational analysis. However this method results in the production of hazardous wastes including mercury and hexavalent chromium. The study examined the replacement of COD with total organic carbon (TOC) for general performance monitoring by comparing their relationship with influent and effluent samples from 11 wastewater treatment plants. Biochemical oxygen demand (BOD5) was also included in the comparison as a control. The results show significant linear relationships between TOC, COD and BOD5 in settled (influent) domestic and municipal wastewaters, but only between COD and TOC in treated effluents. The study concludes that TOC can be reliably used for the generic replacement of both COD (COD=49.2+3.00*TOC) and BOD5 (BOD5=23.7+1.68*TOC) in influent wastewaters but only for COD (COD=7.25+2.99*TOC) in final effluents.
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Lauria, V; Garofalo, G; Gristina, M; Fiorentino, F
2016-08-01
Conservation of fish habitat requires a deeper knowledge of how species distribution patterns are related to environmental factors. Habitat suitability modelling is an essential tool to quantify species' realised niches and understand species-environment relationships. Cephalopods are important players in the marine food web and a significant resource for fisheries; they are also very sensitive to environmental changes. Here a time series of fishery-independent data (1998-2011) was used to construct habitat suitability models and investigate the influence of environmental variables on four commercial cephalopods: Todaropsis eblanae, Illex coindetii, Eledone moschata and Eledone cirrhosa, in the central Mediterranean Sea. The main environmental predictors of cephalopod habitat suitability were depth, seafloor morphology, chlorophyll-a concentration, sea surface temperature and surface salinity. Predictive maps highlighted contrasting habitat selection amongst species. This study identifies areas where the important commercial species of cephalopods are concentrated and provides significant information for a future spatial based approach to fisheries management in the Mediterranean Sea. Copyright © 2016 Elsevier Ltd. All rights reserved.
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Pawlak, J; Nadolna-Ałtyn, K; Szostakowska, B; Pachur, M; Podolska, M
2017-10-12
The parasite fauna of cod (Gadus morhus) is well described, but the life cycles of Baltic cod parasites are known only in general terms. Invertebrates commonly found in the stomach of cod are recognized as intermediate hosts in the life cycles of nematodes or acanthocephalans. The aim of this study was to determine the source of infection of Baltic cod with parasites found in situ in invertebrates present in the cod stomach. Our results indicate that Saduria entomon is both a source of infection of Baltic cod with parasites and an intermediate host in the life cycle of Hysterothylacium aduncum in the Baltic Sea.
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Application of microbial electrolysis cells to treat spent yeast from an alcoholic fermentation.
Sosa-Hernández, Ornella; Popat, Sudeep C; Parameswaran, Prathap; Alemán-Nava, Gibrán Sidney; Torres, César I; Buitrón, Germán; Parra-Saldívar, Roberto
2016-01-01
Spent yeast (SY), a major challenge for the brewing industry, was treated using a microbial electrolysis cell to recover energy. Concentrations of SY from bench alcoholic fermentation and ethanol were tested, ranging from 750 to 1500mgCOD/L and 0 to 2400mgCOD/L respectively. COD removal efficiency (RE), coulombic efficiency (CE), coulombic recovery (CR), hydrogen production and current density were evaluated. The best treatment condition was 750mgCOD/LSY+1200mgCOD/L ethanol giving higher COD RE, CE, CR (90±1%, 90±2% and 81±1% respectively), as compared with 1500mgCOD/LSY (76±2%, 63±7% and 48±4% respectively); ethanol addition was significantly favorable (p value=0.011), possibly due to electron availability and SY autolysis. 1500mgCOD/LSY+1200mgCOD/L ethanol achieved higher current density (222.0±31.3A/m(3)) and hydrogen production (2.18±0.66 [Formula: see text] ) but with lower efficiencies (87±2% COD RE, 71.0±.4% CE). Future work should focus on electron sinks, acclimation and optimizing SY breakdown. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.
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Fox, C J; Taylor, M I; Pereyra, R; Villasana, M I; Rico, C
2005-03-01
Recent substantial declines in northeastern Atlantic cod stocks necessitate improved biological knowledge and the development of techniques to complement standard stock assessment methods (which largely depend on accurate commercial catch data). In 2003, an ichthyoplankton survey was undertaken in the Irish Sea and subsamples of 'cod-like' eggs were analysed using a TaqMan multiplex, PCR (polymerase chain reaction) assay (with specific probes for cod, haddock and whiting). The TaqMan method was readily applied to the large number of samples (n = 2770) generated during the survey and when combined with a manual DNA extraction protocol had a low failure rate of 6%. Of the early stage 'cod-like' eggs (1.2-1.75 mm diameter) positively identified: 34% were cod, 8% haddock and 58% whiting. As previous stock estimates based on egg surveys for Irish Sea cod assumed that the majority of 'cod-like' eggs were from cod, the TaqMan results confirm that there was probably substantial contamination by eggs of whiting and haddock that would have inflated estimates of the stock biomass.
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Who’s your mama? Riverine hybridisation of threatened freshwater Trout Cod and Murray Cod
Unmack, Peter J.; Dyer, Fiona J.; Lintermans, Mark
2016-01-01
Rates of hybridization and introgression are increasing dramatically worldwide because of translocations, restocking of organisms and habitat modifications; thus, determining whether hybridization is occuring after reintroducing extirpated congeneric species is commensurately important for conservation. Restocking programs are sometimes criticized because of the genetic consequences of hatchery-bred fish breeding with wild populations. These concerns are important to conservation restocking programs, including those from the Australian freshwater fish family, Percichthyidae. Two of the better known Australian Percichthyidae are the Murray Cod, Maccullochella peelii and Trout Cod, Maccullochella macquariensis which were formerly widespread over the Murray Darling Basin. In much of the Murrumbidgee River, Trout Cod and Murray Cod were sympatric until the late 1970s when Trout Cod were extirpated. Here we use genetic single nucleotide polymorphism (SNP) data together with mitochondrial sequences to examine hybridization and introgression between Murray Cod and Trout Cod in the upper Murrumbidgee River and consider implications for restocking programs. We have confirmed restocked riverine Trout Cod reproducing, but only as inter-specific matings, in the wild. We detected hybrid Trout Cod–Murray Cod in the Upper Murrumbidgee, recording the first hybrid larvae in the wild. Although hybrid larvae, juveniles and adults have been recorded in hatcheries and impoundments, and hybrid adults have been recorded in rivers previously, this is the first time fertile F1 have been recorded in a wild riverine population. The F1 backcrosses with Murray cod have also been found to be fertile. All backcrosses noted were with pure Murray Cod. Such introgression has not been recorded previously in these two species, and the imbalance in hybridization direction may have important implications for restocking programs. PMID:27812407
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Muñoz-Garcia, Isabel Rosario; Martinez-Perez, Francisco; Ramirez-Perez, Jorge Saul
2018-01-01
The shrimp fishery is one of the most important fisheries in the world, although the low selectivity from trawling nets has led to the capture of a large number of non-target species. Shrimp-bycatch species include a large number of fish and invertebrate species, of which fish species are the most abundant. The present study aims to determine the community structure as well as the average sizes at first maturity of the fish species from shrimp-bycatch caught from industrial fisheries in the Mexican Pacific from Sinaloa to Guerrero, from January to March 2015. The shrimp-bycatch fish diversity value was found to be 2.22. A total of 37 species of finfish were found, of which five were considered rare. The fish species with the highest Importance Value Index (IVI) levels were Pseudupeneus grandisquamis, Paralichthys woolmani, Lutjanus peru and Diapterus peruvianus. The average size at first maturity was calculated for all species. Of the analysed organisms, 90% were in the juvenile stage, including species with riverine and artisanal fisheries. The present study demonstrates the risk within marine populations to different non-target species due to the poor selectivity of shrimp trawls. PMID:29507841
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Pardo, Luis Miguel; Rosas, Yenifer; Fuentes, Juan Pablo; Riveros, Marcela Paz; Chaparro, Oscar Roberto
2015-01-01
Sperm depletion in males can occur when polygynous species are intensively exploited under a male-biased management strategy. In fisheries involving crabs species, the effects of this type of management on the reproductive potential is far from being understood. This study tests whether male-biased management of the principal Chilean crab fishery is able to affect the potential capacity of Metacarcinus edwardsii males to transfer sperm to females. Five localities in southern Chile, recording contrasting crab fishery landing, were selected to assess the potential of sperm depletion triggered by fishery. Seasonally, male crabs from each locality were obtained. Dry weight and histological condition of vasa deferentia and the Vaso-Somatic Index (VSI) were determined in order to use them as proxies for sperm depletion and male reproductive condition. A manipulative experiment was performed in the laboratory to estimate vasa deferentia weight and VSI from just-mated males in order to obtain a reference point for the potential effects of the fishery on sperm reserves. Sperm storage capacity is significantly affected by fisheries; during the mating season vasa deferentia from localities with low fishery intensity were heavier than those from high intensity fisheries, and these differences were even more evident in large males. Histological section showed that this disparity in vasa deferentia weight was explained principally by differences in the quantity of spermatophores rather than other seminal material. VSI was always higher in males from localities with low fishery intensity. Males from localities with high fishery intensity showed little capacity to recover sperm reserves and the VSI of these males remained below the values of the just-mated males. Detriment in the capacity of males to transfer sperm is the first step to sperm limitation in an exploited population, thus detection of sperm depletion can be an alert to introduce changes in the current management of crabs. PMID:25768728
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Species succession and fishery exploitation in the Great Lakes
Smith, Stanford H.
1968-01-01
The species composition of fish in the Great Lakes has undergone continual change since the earliest records. Some changes were caused by enrichment of the environment, but others primarily by an intensive and selective fishery for certain species. Major changes related to the fishery were less frequent before the late 1930's than in recent years and involved few species. Lake sturgeon (Acipenser fulvescens) were overexploited knowingly during the late 1800's because they interfered with fishing for preferred species; sturgeon were greatly reduced in all lakes by the early 1900's. Heavy exploitation accompanied sharp declines of lake herring (Leucichthys artedi) in Lake Erie during the 1920's and lake whitefish (Coregonus clupeaformis) in Lake Huron during the 1930's. A rapid succession of fish species in Lakes Huron, Michigan, and Superior that started about 1940 has been caused by selective predation by the sea lamprey (Petromyzon marinus) on native predatory species, and the resultant shifting emphasis of the fishery and species interaction as various species declined. Lake trout (Salvelinus namaycush) and burbot (Lota lota), the deepwater predators, were depleted first; this favored their prey, the chubs (Leucichthys spp.). The seven species of chubs were influenced differently according to differences in size. Fishing emphasis and predation by sea lampreys were selective for the largest species of chubs as lake trout and burbot declined. A single slow-growing chub, the bloater, was favored and increased, but as the large chubs declined the bloater was exploited by a new trawl fishery. The growth rate and size of the bloater increased, making it more vulnerable to conventional gillnet fishery and lamprey predation. This situation in Lakes Michigan and Huron favored the small alewife (Alosa pseudoharengus) which had recently become established in the upper Great Lakes, and the alewife increased rapidly and dominated the fish stocks of the lakes. The successive collapses of various stocks after periods of stable production may give some indication of their sustainable yield. The sea lamprey is being brought under control in Lakes Superior, Michigan, and Huron; lake trout are being established; and chinook salmon (Oncorhynchus tshawytscha), coho salmon (O. kisutch), kokanee salmon (O. nerka), and the splake, a hybrid of lake trout and brook trout (Salvelinus fontinalis), are being introduced to reestablish a new species balance. Fish stocks are in a state of extreme instability in these lakes. Careful control of stocking programs and fisheries, and coordination of management among the various states of the United States and the province of Canada (Ontario) which manage the fish stocks, will be required to restore and maintain a useful fishery balance.
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Vildmyren, Iselin; Cao, Huy John Vu; Haug, Lina Bowitz; Valand, Ida Ulrikke; Eng, Øyvin; Oterhals, Åge; Austgulen, Maren Hoff; Halstensen, Alfred; Mellgren, Gunnar; Gudbrandsen, Oddrun A
2018-06-05
Improved process technologies have allowed fishing vessels to utilize residuals from cod fillet production (head, backbone, skin, cuttings, and entrails) and convert this to high-quality protein powders for human consumption. In this double-blind pilot study, 42 healthy overweight or obese adults were randomized to three experimental groups consuming tablets corresponding to 6 g/day of proteins from cod residuals as presscake meal (Cod-PC), presscake and stickwater meal (Cod-PCW), or placebo tablets (control) for eight weeks. The primary outcome of this study was changes in metabolites related to glucose regulation in overweight or obese healthy adults after intake of proteins from cod residuals. Cod-PC supplementation decreased postprandial serum nonesterified fatty acids (NEFA) concentration and increased gene expressions of diglyceride acyltransferase 1 and 2 in subcutaneous adipose tissue compared with controls. Fasting insulin increased while fasting NEFA and 120-min postprandial glucose decreased within the Cod-PC group, but these changes did not differ from the other groups. In conclusion, supplementation with Cod-PC beneficially affected postprandial serum NEFA concentration compared with the other groups in overweight or obese adults. Supplementation with Cod-PCW, which contains a higher fraction of water-soluble protein compared to Cod-PC, did not affect serum markers of glucose regulation.
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Hyperstability masks declines in bumphead parrotfish ( Bolbometopon muricatum) populations
NASA Astrophysics Data System (ADS)
Hamilton, Richard J.; Almany, Glenn R.; Stevens, Don; Bode, Michael; Pita, John; Peterson, Nate A.; Choat, J. Howard
2016-09-01
Bolbometopon muricatum, the largest species of parrotfish, is a functionally important species that is characterised by the formation of aggregations for foraging, reproductive, and sleeping behaviours. Aggregations are restricted to shallow reef habitats, the locations of which are often known to local fishers. Bolbometopon muricatum fisheries are therefore vulnerable to overfishing and are likely to exhibit hyperstability, the maintenance of high catch per unit effort (CPUE) while population abundance declines. In this study, we provide a clear demonstration of hyperstable dynamics in a commercial B. muricatum fishery in Isabel Province, Solomon Islands. Initially, we used participatory mapping to demarcate the Kia fishing grounds into nine zones that had experienced different historic levels of fishing pressure. We then conducted comprehensive underwater visual census (UVC) and CPUE surveys across these zones over a 21-month period in 2012-2013. The individual sites for replicate UVC surveys were selected using a generalised random tessellation stratified variable probability design, while CPUE surveys involved trained provincial fisheries officers and local spearfishers. A comparison of fishery-independent abundance data and fishery-dependent CPUE data indicate extreme hyperstability, with CPUE maintained as B. muricatum abundance declines towards zero. Hyperstability may explain the sudden collapses of many B. muricatum spear fisheries across the Pacific and highlights the limitations of using data-poor fisheries assessment methods to evaluate the status of commercially valuable coral reef fishes that form predicable aggregations.
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Catch shares slow the race to fish
NASA Astrophysics Data System (ADS)
Birkenbach, Anna M.; Kaczan, David J.; Smith, Martin D.
2017-04-01
In fisheries, the tragedy of the commons manifests as a competitive race to fish that compresses fishing seasons, resulting in ecological damage, economic waste, and occupational hazards. Catch shares are hypothesized to halt the race by securing each individual’s right to a portion of the total catch, but there is evidence for this from selected examples only. Here we systematically analyse natural experiments to test whether catch shares reduce racing in 39 US fisheries. We compare each fishery treated with catch shares to an individually matched control before and after the policy change. We estimate an average policy treatment effect in a pooled model and in a meta-analysis that combines separate estimates for each treatment-control pair. Consistent with the theory that market-based management ends the race to fish, we find strong evidence that catch shares extend fishing seasons. This evidence informs the current debate over expanding the use of market-based regulation to other fisheries.
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A brief history of commercial fishing in Lake Erie
Applegate, Vernon C.; Van Meter, Harry D.
1970-01-01
Salient features of the development of the industry from about 1815 to 1968, changes in fishing gears and methods, changes in the kinds and abundance of fishes caught, and the attendant effects of disappearing species on the stability of the fishery are described. The history and present status of the walleye, yellow perch, and eight other fishes, still taken in commercial quantities, are presented in more detail and are considered in the context of their effect on the current moribund state of the U.S. fishery. Past and present contributions of Lake Erie's tributaries and northerly connecting waters to the fishery are outlined briefly. The "outlook" for the fishery under present conditions of selective overfishing for high-value species, excessive pollution, ineffective and uncoordinated regulation, and antiquated methods of handling, processing, and marketing fish are discussed, and possible solutions to these problems are suggested.
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Catch shares slow the race to fish.
Birkenbach, Anna M; Kaczan, David J; Smith, Martin D
2017-04-13
In fisheries, the tragedy of the commons manifests as a competitive race to fish that compresses fishing seasons, resulting in ecological damage, economic waste, and occupational hazards. Catch shares are hypothesized to halt the race by securing each individual's right to a portion of the total catch, but there is evidence for this from selected examples only. Here we systematically analyse natural experiments to test whether catch shares reduce racing in 39 US fisheries. We compare each fishery treated with catch shares to an individually matched control before and after the policy change. We estimate an average policy treatment effect in a pooled model and in a meta-analysis that combines separate estimates for each treatment-control pair. Consistent with the theory that market-based management ends the race to fish, we find strong evidence that catch shares extend fishing seasons. This evidence informs the current debate over expanding the use of market-based regulation to other fisheries.
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Zhang, Yun-lin; Yang, Long-yuan; Qin, Bo-qiang; Gao, Guang; Luo, Lian-cong; Zhu, Guang-wei; Liu, Ming-liang
2008-06-01
Spatial variation of chemical oxygen demand (COD) concentration was documented and significant correlations between COD concentration and chromophoric dissolved organic matter (CDOM) absorption, fluorescence, DOC concentration were found based on a cruise sampling in the northern region of Lake Taihu in summer including 42 samplings. The possible source of COD was also discussed using every two cruise samplings in summer and winter, respectively. The COD concentration ranged from 3.77 to 7.96 mg x L(-1) with a mean value of (5.90 +/- 1.54) mg x L(-1). The mean COD concentrations in Meiliang Bay and the central lake basin were (6.93 +/- 0.89) mg x L(-1) and (4.21 +/- 0.49) mg x L(-1) respectively. A significant spatial difference was found between Meiliang Bay and the central lake basin in COD concentration, CDOM absorption coefficient, fluorescence, DOC and phytoplankton pigment concentrations, decreasing from the river mouth to inner bay, outer bay and the central lake basin. Significant correlations between COD concentration and CDOM absorption, fluorescence, DOC concentration, suggested that COD concentration could be estimated and organic pollution could be assessed using CDOM absorption retrieved from remote sensing images. Significant and positive correlation was found between COD concentration and chlorophyll a concentration in summer. However, the correlation was weak or no correlation was found in winter. Furthermore, a significant higher COD concentration was found in summer than in winter (p < 0.001). Our results indicated that degradation of phytoplankton blooms was the main source of COD in summer, except for river terrestrial input.
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Cape Cod Transit Task Force : Five-Year Public Transportation Plan
DOT National Transportation Integrated Search
2002-06-30
The U.S. Department of Transportation's Volpe National Transportation Systems : Center has been working in cooperation with the Cape Cod Regional Transit : Authority, the Cape Cod Commission, and other organizations participating on : the Cape Cod Tr...
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The alarming decline of Mediterranean fish stocks.
Vasilakopoulos, Paraskevas; Maravelias, Christos D; Tserpes, George
2014-07-21
In recent years, fisheries management has succeeded in stabilizing and even improving the state of many global fisheries resources [1-5]. This is particularly evident in areas where stocks are exploited in compliance with scientific advice and strong institutional structures are in place [1, 5]. In Europe, the well-managed northeast (NE) Atlantic fish stocks have been recovering in response to decreasing fishing pressure over the past decade [3-6], albeit with a long way to go for a universal stock rebuild [3, 7]. Meanwhile, little is known about the temporal development of the European Mediterranean stocks, whose management relies on input controls that are often poorly enforced. Here, we perform a meta-analysis of 42 European Mediterranean stocks of nine species in 1990-2010, showing that exploitation rate has been steadily increasing, selectivity (proportional exploitation of juveniles) has been deteriorating, and stocks have been shrinking. We implement species-specific simulation models to quantify changes in exploitation rate and selectivity that would maximize long-term yields and halt stock depletion. We show that stocks would be more resilient to fishing and produce higher long-term yields if harvested a few years after maturation because current selectivity is far from optimal, especially for demersal stocks. The European Common Fisheries Policy that has assisted in improving the state of NE Atlantic fish stocks in the past 10 years has failed to deliver similar results for Mediterranean stocks managed under the same policy. Limiting juvenile exploitation, advancing management plans, and strengthening compliance, control, and enforcement could promote fisheries sustainability in the Mediterranean. Copyright © 2014 Elsevier Ltd. All rights reserved.
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Quaas, Martin F; Reusch, Thorsten B H; Schmidt, Jörn O; Tahvonen, Olli; Voss, Rudi
2016-01-01
Four marine fish species are among the most important on the world market: cod, salmon, tuna, and sea bass. While the supply of North American and European markets for two of these species - Atlantic salmon and European sea bass - mainly comes from fish farming, Atlantic cod and tunas are mainly caught from wild stocks. We address the question what will be the status of these wild stocks in the midterm future, in the year 2048, to be specific. Whereas the effects of climate change and ecological driving forces on fish stocks have already gained much attention, our prime interest is in studying the effects of changing economic drivers, as well as the impact of variable management effectiveness. Using a process-based ecological-economic multispecies optimization model, we assess the future stock status under different scenarios of change. We simulate (i) technological progress in fishing, (ii) increasing demand for fish, and (iii) increasing supply of farmed fish, as well as the interplay of these driving forces under different scenarios of (limited) fishery management effectiveness. We find that economic change has a substantial effect on fish populations. Increasing aquaculture production can dampen the fishing pressure on wild stocks, but this effect is likely to be overwhelmed by increasing demand and technological progress, both increasing fishing pressure. The only solution to avoid collapse of the majority of stocks is institutional change to improve management effectiveness significantly above the current state. We conclude that full recognition of economic drivers of change will be needed to successfully develop an integrated ecosystem management and to sustain the wild fish stocks until 2048 and beyond. © 2015 John Wiley & Sons Ltd.
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Meeting future information needs for Great Lakes fisheries management
Christie, W.J.; Collins, John J.; Eck, Gary W.; Goddard, Chris I.; Hoenig, John M.; Holey, Mark; Jacobson, Lawrence D.; MacCallum, Wayne; Nepszy, Stephen J.; O'Gorman, Robert; Selgeby, James
1987-01-01
Description of information needs for management of Great Lakes fisheries is complicated by recent changes in biology and management of the Great Lakes, development of new analytical methodologies, and a transition in management from a traditional unispecies approach to a multispecies/community approach. A number of general problems with the collection and management of data and information for fisheries management need to be addressed (i.e. spatial resolution, reliability, computerization and accessibility of data, design of sampling programs, standardization and coordination among agencies, and the need for periodic review of procedures). Problems with existing data collection programs include size selectivity and temporal trends in the efficiency of fishing gear, inadequate creel survey programs, bias in age estimation, lack of detailed sea lamprey (Petromyzon marinus) wounding data, and data requirements for analytical techniques that are underutilized by managers of Great Lakes fisheries. The transition to multispecies and community approaches to fisheries management will require policy decisions by the management agencies, adequate funding, and a commitment to develop programs for collection of appropriate data on a long-term basis.
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Federal Great Lakes fishery research objectives, priorities, and projects
Tait, Howard D.
1973-01-01
Fishery productivity of the Great Lakes has declined drastically since settlement of the area. Premium quality fishes of the Great Lakes such as whitefish, lake trout, and walleyes have been replaced by less desired species. This change is attributed to selective overfishing, pollution, and the extreme instability of fish populations. Sea lamprey predation is still a vexing problem but progress is being made in controlling this parasite. The federal fishery research program with headquarters in Ann Arbor, Michigan, has the objective of providing baseline information, needed in resource use decisions, about the fishes of the Great Lakes. Studies of the habitat requirements of fish are high priority. The program includes fish population assessments, studies of the effects of mercury and other contaminants on fish, thermal effects studies, and general investigation of the impact of engineering projects on Great Lakes fisheries. The work is closely coordinated with state and Canadian agencies through the Great Lakes Fishery Commission. Four small research vessels and four field stations are utilized with a staff of 90 and an annual budget of about $1.5 million.
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Zhang, Wei; Zhong, Xing; Che, Wu
2018-02-01
To investigate nutrient leaching from extensive green roofs, green roof platforms were established to investigate the effluent quantity and quality during artificial rainfall. When the influent volume reached three times the empty bed volume, for which the cumulative rainfall was around 300 mm, the effluent TP and COD concentrations of green roof platforms filled with peat soil did not tend to stabilize. For a long-term operation, the substrate depths had little significant influence on TN, TP and COD concentrations of the green roof effluents. A normalized cumulative emission process method was proposed to discuss the difference in various pollutant leaching processes. Obvious differences in the leaching process of different contaminants for green roof platforms filled with various substrates were observed. For the green roof filled with modified substrates, the nitrogen and phosphorus pollutant leaching rates were relatively high in the initial stage of green roof operation and the phosphorus leaching rate was higher than that of nitrogen. The green roof is a sink for TN, but not for TP and COD in this study. The outcomes are critical for the selection of green roof substrates and also contribute to green roof maintenance.
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Zimmerman, Marc J.
2005-01-01
In June 2004, the U.S. Geological Survey, in cooperation with the Barnstable County Department of Health and Environment, sampled water from 14 wastewater sources and drinking-water supplies on Cape Cod, Massachusetts, for the presence of organic wastewater contaminants, pharmaceuticals, and personal care products. The geographic distribution of sampling locations does not represent the distribution of drinking-water supplies on Cape Cod. The environmental presence of the analyte compounds is mostly unregulated; many of the compounds are suspected of having adverse ecological and human health effects. Of the 85 different organic analyte compounds, 43 were detected, with 13 detected in low concentrations (less than 1 microgram per liter) from drinking-water supplies thought to be affected by wastewater because of previously detected high nitrate concentrations. (Phenol and d-limonene, detected in equipment blanks at unacceptably high concentrations, are not included in counts of detections in this report.) Compounds detected in the drinking-water supplies included the solvent, tetrachloroethylene; the analgesic, acetaminophen; the antibiotic, sulfamethoxazole; and the antidepressant, carbamazapine. Nitrate nitrogen, an indicator of wastewater, was detected in water supplies in concentrations ranging from 0.2 to 8.8 milligrams per liter.
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Liu, Xue-Mei; Zhang, Hai-Liang
2014-10-01
Ultraviolet/visible (UV/Vis) spectroscopy was studied for the rapid determination of chemical oxygen demand (COD), which was an indicator to measure the concentration of organic matter in aquaculture water. In order to reduce the influence of the absolute noises of the spectra, the extracted 135 absorbance spectra were preprocessed by Savitzky-Golay smoothing (SG), EMD, and wavelet transform (WT) methods. The preprocessed spectra were then used to select latent variables (LVs) by partial least squares (PLS) methods. Partial least squares (PLS) was used to build models with the full spectra, and back- propagation neural network (BPNN) and least square support vector machine (LS-SVM) were applied to build models with the selected LVs. The overall results showed that BPNN and LS-SVM models performed better than PLS models, and the LS-SVM models with LVs based on WT preprocessed spectra obtained the best results with the determination coefficient (r2) and RMSE being 0. 83 and 14. 78 mg · L(-1) for calibration set, and 0.82 and 14.82 mg · L(-1) for the prediction set respectively. The method showed the best performance in LS-SVM model. The results indicated that it was feasible to use UV/Vis with LVs which were obtained by PLS method, combined with LS-SVM calibration could be applied to the rapid and accurate determination of COD in aquaculture water. Moreover, this study laid the foundation for further implementation of online analysis of aquaculture water and rapid determination of other water quality parameters.
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Horbowy, Jan; Tomczak, Maciej T
2017-01-01
Biomass reconstructions to pre-assessment periods for commercially important and exploitable fish species are important tools for understanding long-term processes and fluctuation on stock and ecosystem level. For some stocks only fisheries statistics and fishery dependent data are available, for periods before surveys were conducted. The methods for the backward extension of the analytical assessment of biomass for years for which only total catch volumes are available were developed and tested in this paper. Two of the approaches developed apply the concept of the surplus production rate (SPR), which is shown to be stock density dependent if stock dynamics is governed by classical stock-production models. The other approach used a modified form of the Schaefer production model that allows for backward biomass estimation. The performance of the methods was tested on the Arctic cod and North Sea herring stocks, for which analytical biomass estimates extend back to the late 1940s. Next, the methods were applied to extend biomass estimates of the North-east Atlantic mackerel from the 1970s (analytical biomass estimates available) to the 1950s, for which only total catch volumes were available. For comparison with other methods which employs a constant SPR estimated as an average of the observed values, was also applied. The analyses showed that the performance of the methods is stock and data specific; the methods that work well for one stock may fail for the others. The constant SPR method is not recommended in those cases when the SPR is relatively high and the catch volumes in the reconstructed period are low.
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Horbowy, Jan
2017-01-01
Biomass reconstructions to pre-assessment periods for commercially important and exploitable fish species are important tools for understanding long-term processes and fluctuation on stock and ecosystem level. For some stocks only fisheries statistics and fishery dependent data are available, for periods before surveys were conducted. The methods for the backward extension of the analytical assessment of biomass for years for which only total catch volumes are available were developed and tested in this paper. Two of the approaches developed apply the concept of the surplus production rate (SPR), which is shown to be stock density dependent if stock dynamics is governed by classical stock-production models. The other approach used a modified form of the Schaefer production model that allows for backward biomass estimation. The performance of the methods was tested on the Arctic cod and North Sea herring stocks, for which analytical biomass estimates extend back to the late 1940s. Next, the methods were applied to extend biomass estimates of the North-east Atlantic mackerel from the 1970s (analytical biomass estimates available) to the 1950s, for which only total catch volumes were available. For comparison with other methods which employs a constant SPR estimated as an average of the observed values, was also applied. The analyses showed that the performance of the methods is stock and data specific; the methods that work well for one stock may fail for the others. The constant SPR method is not recommended in those cases when the SPR is relatively high and the catch volumes in the reconstructed period are low. PMID:29131850
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Treatment of low-strength soluble wastewater using an anaerobic baffled reactor (ABR).
Gopala Krishna, G V T; Kumar, Pramod; Kumar, Pradeep
2009-01-01
Treatment of low-strength soluble wastewater (COD approximately 500 mg/L) was studied using an eight chambered anaerobic baffled reactor (ABR). At pseudo steady-state (PSS), the average total and soluble COD values (COD(T) and COD(S)) at 8h hydraulic retention time (HRT) were found to be around 50 and 40 mg/L, respectively, while at 10h HRT average COD(T) and COD(S) values were of the order of 47 and 37 mg/L, respectively. COD and BOD (3 day, 27 degrees C) removal averaged more than 90%. Effluent conformed to Indian standards laid down for BOD (less than 30 mg/L). Reactor effluent characteristics exhibited very low values of standard deviation indicating excellent reactor stability at PSS in terms of effluent characteristics. Based on mass balance calculations, more than 60% of raw wastewater COD was estimated to be recovered as CH(4) in the gas phase. Compartment-wise profiles indicated that most of the BOD and COD got reduced in the initial compartments only. Sudden drop in pH (7.8-6.7) and formation of volatile fatty acids (VFA) (53-85 mg/L) were observed in the first compartment due to acidogenesis and acetogenesis. The pH increased and VFA concentration decreased longitudinally down the reactor. Residence time distribution (RTD) studies revealed that the flow pattern in the ABR was neither completely plug-flow nor perfectly mixed. Observations from scanning electron micrographs (SEM) suggest that distinct phase separation takes place in an ABR.
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Andersen, Øivind; Frantzen, Marianne; Rosland, Marte; Timmerhaus, Gerrit; Skugor, Adrijana; Krasnov, Aleksei
2015-08-01
Petroleum-related activities in the Arctic have raised concerns about the adverse effects of potential oil spill on the environment and living organisms. Polar cod plays a key role in the Arctic marine ecosystem and is an important species for monitoring oil pollution in this region. We examined potential interactions of oil pollution and global warming by analysing liver transcriptome changes in polar cod exposed to crude oil at elevated temperature. Adult males and females were kept at high (11°C) or normal (4°C) temperature for 5 days before exposure to mechanically dispersed crude oil for 2 days followed by recovery in clean sea water for 11 days at the two temperatures. Genome-wide microarray analysis of liver samples revealed numerous differentially expressed genes induced by uptake of oil as confirmed by increased levels of bile polycyclic aromatic hydrocarbon (PAH) metabolites. The hepatic response included genes playing important roles in xenobiotic detoxification and closely related biochemical processes, but also of importance for protein stress response, cell repair and immunity. Though magnitude of transcriptome responses was similar at both temperatures, the upregulated expression of cyp1a1 and several chaperone genes was much stronger at 11°C. Most gene expression changes returned to basal levels after recovery. The microarray results were validated by qPCR measurement of eleven selected genes representing both known and novel biomarkers to assess exposure to anthropogenic threats on polar cod. Strong upregulation of the gene encoding fibroblast growth factor 7 is proposed to protect the liver of polar fish with aglomerular kidneys from the toxic effect of accumulated biliary compounds. The highly altered liver transcriptome patterns after acute oil exposure and recovery suggests rapid responses in polar cod to oil pollutants and the ability to cope with toxicity in relatively short time. Copyright © 2015 Elsevier B.V. All rights reserved.
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Gauthier-Ouellet, M.; Dionne, M.; Caron, F.; King, T.L.; Bernatchez, L.
2009-01-01
Mixed-stock fisheries refer to the exploitation of admixed fish stocks coming from different origins. We identified the North American origin of 2835 Atlantic salmon (Salmo salar) in the Greenland mixed-stock fishery during 11 years (1995-2006) at three localities using 13 microsatellites. The study included 52 baseline populations representing nine genetically distinct regional groups. The contribution of each group ranged from <1% (Maine) to 40% (Southern Qu??bec). Decreasing temporal contributions were observed for Southern Qu??bec (-22.0%) and New Brunswick (-17.4%), whereas an increasing contribution for Labrador (+14.9%) was observed during the time course of the study. The estimated regional contribution to the Greenland fishery was significantly correlated to the number of multi-sea-winter salmon regionally produced in 2002 (r = 0.79) and 2004 (r = 0.92). No difference in contribution was found between the three Greenland sampling localities. Ungava and Southern Qu??bec regions showed the highest mortality estimates caused by the fishery, ranging from 12.10% to 18.08%, for both years tested. No regional group was overrepresented in landings compared with their respective productivity. Yet, management precautions should still be taken as the fishery strongly selects large females, which could have evolutionary impacts on populations over the long term.
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Viability and Management Targets of Mediterranean Demersal Fisheries: The Case of the Aegean Sea.
Tserpes, George; Nikolioudakis, Nikolaos; Maravelias, Christos; Carvalho, Natacha; Merino, Gorka
2016-01-01
Management of the Mediterranean demersal stocks has proven challenging mainly due to the multi-species character of the fisheries. In the present work, we focus on the multi-species demersal fisheries of the Aegean Sea (eastern Mediterranean) aiming to study the effects of different management measures on the main commercial stocks, as well as to explore the economic viability of the fisheries depending upon these resources, by means of simulated projections. Utilizing the limited available data, our results demonstrated that, under the current exploitation pattern, the economic viability of the fleets is threatened, particularly if fuel prices increase. Additionally, the biological targets set for the most exploited species, such as hake, will not be met under the current management regime. The projections also showed that the only management scenario under which both resource sustainability and economic viability of the fisheries are ensured is the decrease of fleet capacity in terms of vessel numbers. In this case, however, measures to support the fisheries-dependent communities need to be implemented to prevent the collapse of local economies due to employment decrease. Scenarios assuming selectivity improvements would be also beneficial for the stocks but they showed low economic performance and their application would threaten the viability of the fleets, particularly that of the trawlers.
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Levdikov, Vladimir M; Blagova, Elena; Young, Vicki L; Belitsky, Boris R; Lebedev, Andrey; Sonenshein, Abraham L; Wilkinson, Anthony J
2017-02-17
CodY is a branched-chain amino acid (BCAA) and GTP sensor and a global regulator of transcription in low G + C Gram-positive bacteria. It controls the expression of over 100 genes and operons, principally by repressing during growth genes whose products are required for adaptations to nutrient limitation. However, the mechanism by which BCAA binding regulates transcriptional changes is not clear. It is known that CodY consists of a GAF (c G MP-stimulated phosphodiesterases, a denylate cyclases, F hlA) domain that binds BCAAs and a winged helix-turn-helix (wHTH) domain that binds to DNA, but the way in which these domains interact and the structural basis of the BCAA dependence of this interaction are unknown. To gain new insights, we determined the crystal structure of unliganded CodY from Bacillus subtilis revealing a 10-turn α-helix linking otherwise discrete GAF and wHTH domains. The structure of CodY in complex with isoleucine revealed a reorganized GAF domain. In both complexes CodY was tetrameric. Size exclusion chromatography with multiangle laser light scattering (SEC-MALLS) experiments showed that CodY is a dimer at concentrations found in bacterial cells. Comparison of structures of dimers of unliganded CodY and CodY-Ile derived from the tetramers showed a splaying of the wHTH domains when Ile was bound; splaying is likely to account for the increased affinity of Ile-bound CodY for DNA. Electrophoretic mobility shift and SEC-MALLS analyses of CodY binding to 19-36-bp operator fragments are consistent with isoleucine-dependent binding of two CodY dimers per duplex. The implications of these observations for effector control of CodY activity are discussed. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.
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Li, Dong; Lv, Yufeng; Zeng, Huiping; Zhang, Jie
2016-09-01
In this study, a continuous-flow system with enhanced biological phosphorus removal (EBPR) granules was operated at different COD concentrations (200, 300 and 400mgL(-)(1)) to investigate the effect of COD loading on this system. The results showed that when the COD concentration in influent was increased to 400mgL(-)(1), the anaerobic COD removal efficiency and total phosphorus removal efficiency reduced obviously and the settling ability of granules deteriorated due to the proliferation of filamentous bacteria. Moreover, high COD loading inhibited the EPS secretion and destroyed the stability of granules. Results of high-through pyrosequencing indicated that filamentous bacteria had a competitive advantage over polyphosphate-accumulating organisms (PAOs) at high COD loading. The performance of system, settling ability of granules and proportion of PAOs gradually recovered to the initial level after the COD concentration was reduced to 200mgL(-)(1) on day 81. Copyright © 2016 Elsevier Ltd. All rights reserved.
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Li, Na; Kakarla, Ramesh; Moon, Jung Mi; Min, Booki
2015-07-01
Microbial fuel cells (MFCs) have gathered attention as a novel bioenergy technology to simultaneously treat wastewater with less sludge production than the conventional activated sludge system. In two different operations of the MFC and aerobic process, microbial growth was determined by the protein assay method and their biomass yields using real wastewater were compared. The biomass yield on the anode electrode of the MFC was 0.02 g-COD-cell/g- COD-substrate and the anolyte planktonic biomass was 0.14 g-COD-cell/g-COD-substrate. An MFC without anode electrode resulted in the biomass yield of 0.07 ± 0.03 g-COD-cell/g-COD-substrate, suggesting that oxygen diffusion from the cathode possibly supported the microbial growth. In a comparative test, the biomass yield under aerobic environment was 0.46 ± 0.07 g-COD-cell/g-COD-substrate, which was about 3 times higher than the total biomass value in the MFC operation.
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Co-Inactivation of GlnR and CodY Regulators Impacts Pneumococcal Cell Wall Physiology.
Johnston, Calum; Bootsma, Hester J; Aldridge, Christine; Manuse, Sylvie; Gisch, Nicolas; Schwudke, Dominik; Hermans, Peter W M; Grangeasse, Christophe; Polard, Patrice; Vollmer, Waldemar; Claverys, Jean-Pierre
2015-01-01
CodY, a nutritional regulator highly conserved in low G+C Gram-positive bacteria, is essential in Streptococcus pneumoniae (the pneumococcus). A published codY mutant possessed suppressing mutations inactivating the fatC and amiC genes, respectively belonging to iron (Fat/Fec) and oligopeptide (Ami) ABC permease operons, which are directly repressed by CodY. Here we analyzed two additional published codY mutants to further explore the essentiality of CodY. We show that one, in which the regulator of glutamine/glutamate metabolism glnR had been inactivated by design, had only a suppressor in fecE (a gene in the fat/fec operon), while the other possessed both fecE and amiC mutations. Independent isolation of three different fat/fec suppressors thus establishes that reduction of iron import is crucial for survival without CodY. We refer to these as primary suppressors, while inactivation of ami, which is not essential for survival of codY mutants and acquired after initial fat/fec inactivation, can be regarded as a secondary suppressor. The availability of codY- ami+ cells allowed us to establish that CodY activates competence for genetic transformation indirectly, presumably by repressing ami which is known to antagonize competence. The glnR codY fecE mutant was then found to be only partially viable on solid medium and hypersensitive to peptidoglycan (PG) targeting agents such as the antibiotic cefotaxime and the muramidase lysozyme. While analysis of PG and teichoic acid composition uncovered no alteration in the glnR codY fecE mutant compared to wildtype, electron microscopy revealed altered ultrastructure of the cell wall in the mutant, establishing that co-inactivation of GlnR and CodY regulators impacts pneumococcal cell wall physiology. In light of rising levels of resistance to PG-targeting antibiotics of natural pneumococcal isolates, GlnR and CodY constitute potential alternative therapeutic targets to combat this debilitating pathogen, as co-inactivation of these regulators renders pneumococci sensitive to iron and PG-targeting agents.
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Zuo, Shaozhi; Huwer, Bastian; Bahlool, Qusay; Al-Jubury, Azmi; Daugbjerg Christensen, Nanna; Korbut, Rozalia; Kania, Per; Buchmann, Kurt
2016-06-15
A significant increase in the infection level of Baltic cod Gadus morhua with the anisakid nematode larvae Contracaecum osculatum and Pseudoterranova decipiens has been recorded during recent years due to the expanding local population of grey seals Halichoerus grypus, which act as final hosts for these parasites. Here, we report from an investigation of 368 cod (total length [TL] 6-49 cm; caught in ICES Subdivision 25) that the infection level of juvenile cod (TL 6-30 cm) with larvae of C. osculatum and P. decipiens is absent or very low, whereas it increases drastically in larger cod (TL 31-48 cm). A third nematode Hysterothylacium aduncum was rarely found. The study indicates that the prey animals for large cod act as transport hosts for the parasite larvae. Analyses of stomach contents of cod caught in the same area (2007-2014) showed that small benthic organisms (including polychaetes Harmothoë sarsi) are preferred food items by small cod, the isopod Saduria entomon is taken by all size classes, and sprat Sprattus sprattus are common prey items for cod larger than 30 cm. Parasitological investigations (microscopic and molecular analyses) of H. sarsi (100 specimens) and S. entomon (40 specimens) did not reveal infection in these invertebrates, but 11.6% of sprat (265 specimens examined) was shown to be infected with 1-8 C. osculatum third stage larvae per fish. Analyses of sprat stomach contents confirmed that copepods and cladocerans are the main food items of sprat. These observations suggest that the C. osculatum life cycle in the Baltic Sea includes grey seals as final hosts, sprat as the first transport host and cod as second transport host. It may be speculated that sprat obtain infection by feeding on copepods and/or cladocerans, which could serve as the first intermediate hosts. One cannot exclude the possibility that the size-dependent C. osculatum infection of cod may contribute (indirectly or directly) to the differential mortality of larger cod (>38 cm) compared to smaller cod (<30 cm) recently recorded in the Baltic cod population.
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Yu, Zheng-zhe; Sun, De-zhi; Li, Chang-hai; Shi, Peng-fei; Duan, Xiao-dong; Sun, Guo-rong; Liu, Jun-xin
2004-01-01
The performance of UV/H2O2, UV/O3 and UV/H2O2/O3 oxidation systems for treating spent caustic from an ethylene plant was investigated. In UV/H2O2 system, with the increase of H2O2 dosage, removal efficiencies of COD and the ratio of biochemical oxygen demand (BOD) to chemical oxygen demand (COD) of the effluent were increased and a better performance was obtained than the H2O2 system alone. In UV/H2O2 system, removal efficiency of COD reach 68% under the optimum condition, and BOD/COD ratio was significantly increased from 0.22 to 0.52. In UV/O3 system, with the increase of O3 dosage, removal efficiency of COD and BOD/COD ratio were increased, and a better performance was obtained than the O3 system alone. Under the optimum condition, removal efficiency of COD was 54%, and BOD/COD ratio was significantly increased from 0.22 to 0.48. In UV/H2O2/O3 system, COD removal efficiency was found to be 22.0% higher than UV/O3 system.
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Harrisson, K; Pavlova, A; Gan, H M; Lee, Y P; Austin, C M; Sunnucks, P
2016-06-01
Climatic differences across a taxon's range may be associated with specific bioenergetic demands and may result in genetics-based metabolic adaptation, particularly in aquatic ectothermic organisms that rely on heat exchange with the environment to regulate key physiological processes. Extending down the east coast of Australia, the Great Dividing Range (GDR) has a strong influence on climate and the evolutionary history of freshwater fish species. Despite the GDR acting as a strong contemporary barrier to fish movement, many species, and species with shared ancestries, are found on both sides of the GDR, indicative of historical dispersal events. We sequenced complete mitogenomes from the four extant species of the freshwater cod genus Maccullochella, two of which occur on the semi-arid, inland side of the GDR, and two on the mesic coastal side. We constructed a dated phylogeny and explored the relative influences of purifying and positive selection in the evolution of mitogenome divergence among species. Results supported mid- to late-Pleistocene divergence of Maccullochella across the GDR (220-710 thousand years ago), bringing forward previously reported dates. Against a background of pervasive purifying selection, we detected potentially functionally relevant fixed amino acid differences across the GDR. Although many amino acid differences between inland and coastal species may have become fixed under relaxed purifying selection in coastal environments rather than positive selection, there was evidence of episodic positive selection acting on specific codons in the Mary River coastal lineage, which has consistently experienced the warmest and least extreme climate in the genus.
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Harrisson, K; Pavlova, A; Gan, H M; Lee, Y P; Austin, C M; Sunnucks, P
2016-01-01
Climatic differences across a taxon's range may be associated with specific bioenergetic demands and may result in genetics-based metabolic adaptation, particularly in aquatic ectothermic organisms that rely on heat exchange with the environment to regulate key physiological processes. Extending down the east coast of Australia, the Great Dividing Range (GDR) has a strong influence on climate and the evolutionary history of freshwater fish species. Despite the GDR acting as a strong contemporary barrier to fish movement, many species, and species with shared ancestries, are found on both sides of the GDR, indicative of historical dispersal events. We sequenced complete mitogenomes from the four extant species of the freshwater cod genus Maccullochella, two of which occur on the semi-arid, inland side of the GDR, and two on the mesic coastal side. We constructed a dated phylogeny and explored the relative influences of purifying and positive selection in the evolution of mitogenome divergence among species. Results supported mid- to late-Pleistocene divergence of Maccullochella across the GDR (220–710 thousand years ago), bringing forward previously reported dates. Against a background of pervasive purifying selection, we detected potentially functionally relevant fixed amino acid differences across the GDR. Although many amino acid differences between inland and coastal species may have become fixed under relaxed purifying selection in coastal environments rather than positive selection, there was evidence of episodic positive selection acting on specific codons in the Mary River coastal lineage, which has consistently experienced the warmest and least extreme climate in the genus. PMID:26883183
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Federal Register 2010, 2011, 2012, 2013, 2014
2011-07-08
...)(2), the Regional Administrator based his selection on the following criteria: 1. The number and...; selection of an authorized distributor. SUMMARY: NMFS announces the renewal of permits to SeaShare..., NMFS must announce the selection each authorized distributor in the Federal Register and issue one or...
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Performance assessment of aquatic macrophytes for treatment of municipal wastewater
2014-01-01
The objective of the study was to evaluate the performance of three different aquatic macrophytes for treatment of municipal wastewater collected from Taxila (Pakistan). A physical model of treatment plant was constructed and was operated for six experimental runs with each species of macrophyte. Every experimental run consist of thirty days period. Regular monitoring of influent and effluent concentrations were made during each experimental run. For the treatment locally available macrophyte species i.e. water hyacinth, duckweed & water lettuce were selected to use. To evaluate the treatment performance of each macrophyte, BOD5, COD, and Nutrients (Nitrogen and Phosphorus) were monitored in effluent from model at different detention time of every experimental run after ensuring steady state conditions. The average reduction of effluent value of each parameter using water hyacinth were 50.61% for BOD5, 46.38% for COD, 40.34% for Nitrogen and 18.76% for Phosphorus. For duckweed the average removal efficiency for selected parameters were 33.43% for BOD5, 26.37% for COD, 17.59% for Nitrogen and 15.25% for Phosphorus and for Water Lettuce the average removal efficiency were 33.43% for BOD5, 26.37% for COD, 17.59% for Nitrogen and 15.25% for Phosphorus. The mechanisms of pollutant removal in this system include both aerobic and anaerobic microbiological conversions, sorption, sedimentation, volatilization and chemical transformations. The rapid growth of the biomass was measured within first ten days detention time. It was also observed that performance of macrophytes is influenced by variation of pH and Temperature. A pH of 6-9 and Temperature of 15-38°C is most favorable for treatment of wastewater by macrophytes. The option of macrophytes for treatment of Municipal sewage under local environmental conditions can be explored by further verifying the removal efficiency under variation of different environmental conditions. Also this is need of time that macrophyte system should be used for treatment of wastewater because their performance is comparable to conventional wastewater treatment plants and also the system has very low O&M costs. PMID:25089203
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Shi, Wei; Xia, Jun
2017-02-01
Water quality risk management is a global hot research linkage with the sustainable water resource development. Ammonium nitrogen (NH 3 -N) and permanganate index (COD Mn ) as the focus indicators in Huai River Basin, are selected to reveal their joint transition laws based on Markov theory. The time-varying moments model with either time or land cover index as explanatory variables is applied to build the time-varying marginal distributions of water quality time series. Time-varying copula model, which takes the non-stationarity in the marginal distribution and/or the time variation in dependence structure between water quality series into consideration, is constructed to describe a bivariate frequency analysis for NH 3 -N and COD Mn series at the same monitoring gauge. The larger first-order Markov joint transition probability indicates water quality state Class V w , Class IV and Class III will occur easily in the water body of Bengbu Sluice. Both marginal distribution and copula models are nonstationary, and the explanatory variable time yields better performance than land cover index in describing the non-stationarities in the marginal distributions. In modelling the dependence structure changes, time-varying copula has a better fitting performance than the copula with the constant or the time-trend dependence parameter. The largest synchronous encounter risk probability of NH 3 -N and COD Mn simultaneously reaching Class V is 50.61%, while the asynchronous encounter risk probability is largest when NH 3 -N and COD Mn is inferior to class V and class IV water quality standards, respectively.
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Marine reserves solve an important bycatch problem in fisheries
Hastings, Alan; Gaines, Steven D.; Costello, Christopher
2017-01-01
Management of the diverse fisheries of the world has had mixed success. While managing single species in data-rich environments has been largely effective, perhaps the greatest challenge facing fishery managers is how to deal with mixed stocks of fish with a range of life histories that reside in the same location. Because many fishing gears are nonselective, and the costs of making gear selective can be high, a particular problem is bycatch of weak stocks. This problem is most severe when the weak stock is long-lived and has low fecundity and thus requires a very long recovery time once overfished. We investigate the role that marine reserves might play in solving this challenging and ubiquitous problem in ecosystem-based management. Evidence for marine reserves’ potential to manage fisheries in an ecosystem context has been mixed, so we develop a heuristic strategic mathematical model to obtain general conclusions about the merits of managing multispecies fisheries by using reserves relative to managing them with nonspatial approaches. We show that for many fisheries, yields of strong stocks can be increased, and persistence of weak stocks can be ensured, by using marine reserves rather than by using traditional nonspatial approaches alone. Thus, reserves have a distinct advantage as a management tool in many of the most critical multispecies settings. We also show how the West Coast groundfish fishery of the United States meets these conditions, suggesting that management by reserves may be a superior option in that case. PMID:28794280
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The evolutionary legacy of size-selective harvesting extends from genes to populations
Uusi-Heikkilä, Silva; Whiteley, Andrew R; Kuparinen, Anna; Matsumura, Shuichi; Venturelli, Paul A; Wolter, Christian; Slate, Jon; Primmer, Craig R; Meinelt, Thomas; Killen, Shaun S; Bierbach, David; Polverino, Giovanni; Ludwig, Arne; Arlinghaus, Robert
2015-01-01
Size-selective harvesting is assumed to alter life histories of exploited fish populations, thereby negatively affecting population productivity, recovery, and yield. However, demonstrating that fisheries-induced phenotypic changes in the wild are at least partly genetically determined has proved notoriously difficult. Moreover, the population-level consequences of fisheries-induced evolution are still being controversially discussed. Using an experimental approach, we found that five generations of size-selective harvesting altered the life histories and behavior, but not the metabolic rate, of wild-origin zebrafish (Danio rerio). Fish adapted to high positively size selective fishing pressure invested more in reproduction, reached a smaller adult body size, and were less explorative and bold. Phenotypic changes seemed subtle but were accompanied by genetic changes in functional loci. Thus, our results provided unambiguous evidence for rapid, harvest-induced phenotypic and evolutionary change when harvesting is intensive and size selective. According to a life-history model, the observed life-history changes elevated population growth rate in harvested conditions, but slowed population recovery under a simulated moratorium. Hence, the evolutionary legacy of size-selective harvesting includes populations that are productive under exploited conditions, but selectively disadvantaged to cope with natural selection pressures that often favor large body size. PMID:26136825
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Bioacoustic Absorption Spectroscopy (ASIAEX)
2000-09-30
source level of 170 dB re 1 µPa at 1 m for 24 hours. This source will weigh less than 220 ponds, including batteries, and excluding the anchor and float...in the proposed collaborative effort. Dr. Masahiko Furusawa of the University of Tokyo (Fisheries), Japan’s leading authority on fisheries acoustics...about 20 water depths (~ 1.2 km in 60 m of water) at frequencies of 1 to 2 kHz. RESULTS I reviewed the measurements and times of frequency selective
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Viral hemorrhagic septicemia virus in North America
Meyers, Theodore R.; Winton, James R.
1995-01-01
The first detections of viral hemorrhagic septicemia virus (VHSV) in North America were in Washington State from adult coho (Oncorhynchus kisutch) and chinook (O. tshawytscha) salmon in 1988. Subsequently, VHSV was isolated from adult coho salmon returning to hatcheries in the Pacific Northwest in 1989, 1991 and 1994. These isolates represented a strain of VHSV that was genetically different from European VHSV as determined by DNA sequence analysis and T1 ribonuclease fingerprinting. The North American strain of VHSV was also isolated from skin lesions of Pacific cod (Gadus macrocephalus) taken from Prince William Sound (PWS), Alaska in 1990, 1991 and 1993. In 1993 and 1994, the virus was isolated from Pacific herring (Clupea harengus pallasi) in Alaskan waters of PWS, Kodiak Island, Auke Bay and Port Frederick. During 1993 and 1994 the herring fishery in PWS failed from a probable complex of environmental stressors but VHSV isolates were associated with hemorrhages of the skin and fins in fish that returned to spawn. Also in 1993 and 1994, VHSV was isolated from apparently healthy stocks of herring in British Columbia, Canada and Puget Sound, Washington. Thus, the North American strain of VHSV is enzootic in the Northeastern Pacific Ocean among Pacific herring stocks with Pacific cod serving as a secondary reservoir. Although the North American strain of the virus appears to be moderately pathogenic for herring, causing occasional self-limiting epizootics, it was shown to be relatively avirulent for several species of salmonids. Pacific herring are common prey for cod and salmon and were most probably the source of the VHSV isolates from the adult salmon returning to spawn in rivers or at hatcheries in Washington State. Compelling circumstances involving the European isolates of VHSV suggest that this strain of the virus also is enzootic among marine fish in the Atlantic Oean. The highly pathogenic nature of the European strain of VHSV for salmonid fish may be the result of the exposure of rainbow trout (O. mykiss), an introduced species, in a stressful environment of intensive culture and the high rate of mutation inherent in all rhabdoviruses. Consequently, we recommend that efforts be made to eradicate the North American strain of VHSV when detected in live salmonids to reduce the possibility of its evolution into a more virulent salmonid virus.
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A Murray Cod Assemblage: Re/Considering Riverscape Pedagogy
ERIC Educational Resources Information Center
Stewart, Alistair James
2018-01-01
This article enacts Deleuze and Guattari's (1987) concept "assemblage" to craft a riverScape pedagogy that is informed by, and responsive to, the Murray Cod, the river, and its circumstances. The Murray Cod, the largest fish species in Australia's Murray-Darling Basin, has diverse cultural meanings. Cod are at once a creation being of…
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Federal Register 2010, 2011, 2012, 2013, 2014
2012-02-17
... DEPARTMENT OF THE INTERIOR National Park Service [1730-SZM] Cape Cod National Seashore Advisory Commission; Cape Cod National Seashore, South Wellfleet, MA AGENCY: National Park Service, Interior. ACTION... National Seashore, 99 Marconi Site Road, Wellfleet, MA 02667. Date: February 7, 2012. George E. Price, Jr...
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Ghunmi, Lina Abu; Zeeman, Grietje; Fayyad, Manar; van Lier, Jules B
2011-02-01
Knowing the biodegradability characteristics of grey water constituents is imperative for a proper design and operation of a biological treatment system of grey water. This study characterizes the different COD fractions of dormitory grey water and investigates the effect of applying different conditions in the biodegradation test. The maximum aerobic and anaerobic biodegradability and conversion rate for the different COD fractions is determined. The results show that, on average, dormitory grey water COD fractions are 28% suspended, 32% colloidal and 40% dissolved. The studied factors incubation time, inoculum addition and temperature are influencing the determined biodegradability. The maximum biodegradability and biodegradation rate differ between different COD fractions, viz. COD(ss), COD(col) and COD(diss). The dissolved COD fraction is characterised by the lowest degradation rate, both for anaerobic and aerobic conditions. The maximum biodegradability for aerobic and anaerobic conditions is 86 and 70% respectively, whereas the first order conversion rate constant, k₂₀, is 0.119 and 0.005 day⁻¹, respectively. The anaerobic and aerobic conversion rates in relation to temperature can be described by the Arrhenius relation, with temperature coefficients of 1.069 and 1.099, respectively.
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Guldager, H S; Bøknaes, N; Osterberg, C; Nielsen, J; Dalgaard, P
1998-09-01
The effect of two months of frozen storage at -20 degrees C on the spoilage characteristics and shelf life of thawed and modified atmosphere packed (MAP) cod fillets stored at 2 degrees C was studied. Thawed MAP cod fillets were compared with fresh cod fillets stored in CO2-containing modified atmospheres with and without added oxygen. The shelf life of 11 to 12 days in the fresh MAP cod was extended to more than 20 days in the thawed MAP cod at 2 degrees C. This shelf life extension was most likely due to the inactivation of the spoilage bacterium Photobacterium phosphoreum during frozen storage as reflected both in chemical analyses and sensory evaluation. In contrast to fresh MAP cod fillets no significant production of trimethylamine occurred and almost no amine odor and taste were detected during 20 days of chill storage of thawed MAP cod fillets. The use of frozen fillets as raw material not only provides a more stable product in MAP but also allows much greater flexibility for production and distribution. However, a slightly increased concentration of dimethylamine, a larger drip loss, and detection of weak frozen storage flavor were observed in the thawed MAP cod fillets.
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NASA Astrophysics Data System (ADS)
Samudro, Ganjar; Syafrudin; Nugraha, Winardi Dwi; Sutrisno, Endro; Priyambada, Ika Bagus; Muthi'ah, Hilma; Sinaga, Glory Natalia; Hakiem, Rahmat Tubagus
2018-02-01
This research is conducted to analyze and determine the optimum of COD concentration containing leaves litter, canteen and composite waste to power density and COD removal efficiency as the indicator of SMFC performance. COD as the one of organic matter parameters perform as substrate, nutrient and dominating the whole process of SMFC. Leaves litter and canteen based food waste were obtained from TPST UNDIP in Semarang and treated in SMFC reactor. Its reactor was designed 2 liter volume and equipped by homemade graphene electrodes that were utilized at the surface of organic waste as cathode and in a half of reactor height as anode. COD concentration was initially characterized and became variations of initial COD concentration. Waste volume was maintained 2/3 of volume of reactor. Bacteria sources as the important process factor in SMFC were obtained from river sediment which contain bacteroides and exoelectrogenic bacteria. Temperature and pH were not maintained while power density and COD concentration were periodically observed and measured during 44 days. The results showed that power density up to 4 mW/m2 and COD removal efficiency performance up to 70% were reached by leaves litter, canteen and composite waste at days 11 up to days 44 days. Leaves litter contain 16,567 mg COD/l providing higher COD removal efficiency reached approximately 87.67%, more stable power density reached approximately 4.71 mW/m2, and faster optimum time in the third day than canteen based food waste and composite waste. High COD removal efficiency has not yet resulted in high power density.
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Diet of Norwegian coastal cod (Gadus morhua) studied by using citizen science
NASA Astrophysics Data System (ADS)
Enoksen, Siri Elise; Reiss, Henning
2018-04-01
The Norwegian coastal cod (Gadus morhua) is a keystone species in the food web of northern Norwegian fjords. Their relatively stationary populations might specifically depend on local food resources, but the diet of cod has rarely been studied in fjord systems. Using a citizen science approach, where recreational anglers and tourists participated in the sampling, we studied small-scale differences in the diet composition of cod in a fjord system in northern Norway. We compared the cod diet from the MPA Saltstraumen, characterised by strong tidal currents and a highly diverse and abundant fauna, with the inner fjord area of Skjerstadfjord. The diet composition of cod significantly differed between both areas within the fjord. Although fish was the dominant prey in both areas, cod consumed > 40% invertebrates in terms of weight, even in the cod size class of 70-99 cm. The invertebrate prey also caused the observed spatial differences. In Saltstraumen, brittle stars (Ophiuroidea), crabs (Brachyura) and sea cucumbers (Holothuroidea) were important food sources for cod, while sea urchins (Echinoidea), clams (Bivalvia), shrimps (Caridea) and krill (Euphausiacea) dominated the diet in the inner Skjerstadfjord. The high densities of sessile fauna in the dynamic environment of Saltstraumen, was only partly reflected in the diet of cod, with only Holothuroidea found in 17% of the stomachs. High rates of empty stomachs (24%), cannibalism as well as a higher proportion of low-energy prey in the diet of large cod, may indicate a shortage of high quality food in Skjerstadfjord. The samples for this study were collected through a citizen science campaign. This approach might provide opportunities to be used for coastal ecological monitoring with potential applications in local ecosystem management strategies through public involvement.
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Elutriated acid fermentation of municipal primary sludge.
Ahn, Young Ho; Speece, Richard E
2006-06-01
The performance of a novel fermentation process, adopting a sludge blanket type configuration, for higher hydrolysis/acidogenesis of the municipal primary sludge was investigated under batch and semi-continuous conditions with varying pH and temperature. This acid elutriation slurry reactor provided higher system performance with a short HRT (5d) and higher acidogenic effluent quality under pH 9 and thermophilic (55 degrees C) conditions. The hydrolysis of the sludge was revealed to be significantly dependent on seasonal effects for sludge characteristics but with little impact on acidogenesis. Based on the rainy season at the optimal conditions, VFA production and recovery fraction (VFA(COD)/COD) were 0.18 g VFA(COD)/g VSS(COD) and 63%. As byproducts, nitrogen and phosphorus release were measured at 0.006 g N/g VSS(COD) and 0.003 g P/g VSS(COD), respectively. For the mass balance in a full-scale plant (Q=158,880 m(3)/d) based on the rainy season, the VFA and non-VFA (as COD) production were 3110 kg VFA(COD)/d and 1800 kg COD/d, resulting in an increase of organics of 31 mg COD/L and 20mg VFA(COD)/L and nutrients of 0.7 mg N/L and 0.3 mg P/L in the influent sewage. The economical benefit from this process application was estimated to be about 67 dollars per 1000 m(3) of sewage except for energy requirements and also, better benefits can be expected during the dry season. Moreover, the results revealed that the process has various additional advantages such as pathogen-free stabilized solids production, excellent solids control and economical benefits.
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Leo, Elettra; Kunz, Kristina L; Schmidt, Matthias; Storch, Daniela; Pörtner, Hans-O; Mark, Felix C
2017-01-01
Ocean acidification and warming are happening fast in the Arctic but little is known about the effects of ocean acidification and warming on the physiological performance and survival of Arctic fish. In this study we investigated the metabolic background of performance through analyses of cardiac mitochondrial function in response to control and elevated water temperatures and P CO 2 of two gadoid fish species, Polar cod ( Boreogadus saida ), an endemic Arctic species, and Atlantic cod ( Gadus morhua ), which is a temperate to cold eurytherm and currently expanding into Arctic waters in the wake of ocean warming. We studied their responses to the above-mentioned drivers and their acclimation potential through analysing the cardiac mitochondrial function in permeabilised cardiac muscle fibres after 4 months of incubation at different temperatures (Polar cod: 0, 3, 6, 8 °C and Atlantic cod: 3, 8, 12, 16 °C), combined with exposure to present (400μatm) and year 2100 (1170μatm) levels of CO 2 . OXPHOS, proton leak and ATP production efficiency in Polar cod were similar in the groups acclimated at 400μatm and 1170μatm of CO 2 , while incubation at 8 °C evoked increased proton leak resulting in decreased ATP production efficiency and decreased Complex IV capacity. In contrast, OXPHOS of Atlantic cod increased with temperature without compromising the ATP production efficiency, whereas the combination of high temperature and high P CO 2 depressed OXPHOS and ATP production efficiency. Polar cod mitochondrial efficiency decreased at 8 °C while Atlantic cod mitochondria were more resilient to elevated temperature; however, this resilience was constrained by high P CO 2 . In line with its lower habitat temperature and higher degree of stenothermy, Polar cod has a lower acclimation potential to warming than Atlantic cod.
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Lobel, Lior; Herskovits, Anat A.
2016-01-01
Bacteria sense and respond to many environmental cues, rewiring their regulatory network to facilitate adaptation to new conditions/niches. Global transcription factors that co-regulate multiple pathways simultaneously are essential to this regulatory rewiring. CodY is one such global regulator, controlling expression of both metabolic and virulence genes in Gram-positive bacteria. Branch chained amino acids (BCAAs) serve as a ligand for CodY and modulate its activity. Classically, CodY was considered to function primarily as a repressor under rich growth conditions. However, our previous studies of the bacterial pathogen Listeria monocytogenes revealed that CodY is active also when the bacteria are starved for BCAAs. Under these conditions, CodY loses the ability to repress genes (e.g., metabolic genes) and functions as a direct activator of the master virulence regulator gene, prfA. This observation raised the possibility that CodY possesses multiple functions that allow it to coordinate gene expression across a wide spectrum of metabolic growth conditions, and thus better adapt bacteria to the mammalian niche. To gain a deeper understanding of CodY’s regulatory repertoire and identify direct target genes, we performed a genome wide analysis of the CodY regulon and DNA binding under both rich and minimal growth conditions, using RNA-Seq and ChIP-Seq techniques. We demonstrate here that CodY is indeed active (i.e., binds DNA) under both conditions, serving as a repressor and activator of different genes. Further, we identified new genes and pathways that are directly regulated by CodY (e.g., sigB, arg, his, actA, glpF, gadG, gdhA, poxB, glnR and fla genes), integrating metabolism, stress responses, motility and virulence in L. monocytogenes. This study establishes CodY as a multifaceted factor regulating L. monocytogenes physiology in a highly versatile manner. PMID:26895237
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Oygard, Joar Karsten; Måge, Amund; Gjengedal, Elin; Svane, Tore
2005-01-01
Landfill leachates sampled during and after an accidental landfill fire were analysed and the levels of selected metals and chemical compounds compared to those occurring in the leachate under normal conditions. The fire at the landfill site was put out by excavation and cooling by use of water. The investigation during the fire and fire fight revealed a moderate increase in the level of nitrogen and also in pH and conductivity. Heavy metals and COD in the leachate showed considerably increased levels. In general, the determined variables appeared to normalise within one week after the fire was extinguished. It can be concluded that landfill fires extinguished by excavation may lead to elevated leachate levels of especially COD and heavy metals, but that this is only a short-term effect.
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Li, Jihong; Freedman, John C; McClane, Bruce A
2015-10-01
Clostridium perfringens type D strains are usually associated with diseases of livestock, and their virulence requires the production of epsilon toxin (ETX). We previously showed (J. Li, S. Sayeed, S. Robertson, J. Chen, and B. A. McClane, PLoS Pathog 7:e1002429, 2011, http://dx.doi.org/10.1371/journal.ppat.1002429) that BMC202, a nanI null mutant of type D strain CN3718, produces less ETX than wild-type CN3718 does. The current study proved that the lower ETX production by strain BMC202 is due to nanI gene disruption, since both genetic and physical (NanI or sialic acid) complementation increased ETX production by BMC202. Furthermore, a sialidase inhibitor that interfered with NanI activity also reduced ETX production by wild-type CN3718. The NanI effect on ETX production was shown to involve reductions in codY and ccpA gene transcription levels in BMC202 versus wild-type CN3718. Similar to CodY, CcpA was found to positively control ETX production. A double codY ccpA null mutant produced even less ETX than a codY or ccpA single null mutant. CcpA bound directly to sequences upstream of the etx or codY start codon, and bioinformatics identified putative CcpA-binding cre sites immediately upstream of both the codY and etx start codons, suggesting possible direct CcpA regulatory effects. A ccpA mutation also decreased codY transcription, suggesting that CcpA effects on ETX production can be both direct and indirect, including effects on codY transcription. Collectively, these results suggest that NanI, CcpA, and CodY work together to regulate ETX production, with NanI-generated sialic acid from the intestines possibly signaling type D strains to upregulate their ETX production and induce disease. Clostridium perfringens NanI was previously shown to increase ETX binding to, and cytotoxicity for, MDCK host cells. The current study demonstrates that NanI also regulates ETX production via increased transcription of genes encoding the CodY and CcpA global regulators. Results obtained using single ccpA or codY null mutants and a ccpA codY double null mutant showed that codY and ccpA regulate ETX production independently of one another but that ccpA also affects codY transcription. Electrophoretic mobility shift assays and bioinformatic analyses suggest that both CodY and CcpA may directly regulate etx transcription. Collectively, results of this study suggest that sialic acid generated by NanI from intestinal sources signals ETX-producing C. perfringens strains, via CcpA and CodY, to upregulate ETX production and cause disease. Copyright © 2015, American Society for Microbiology. All Rights Reserved.
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The electrical resistivity meter in fishery investigations
Lennon, Robert E.
1959-01-01
A portable resistivity (or conductivity) meter is easily used in fishery investigations to obtain rapid and precise measurements of the electrical resistance (or conductance) of waters. These measurements can be used to estimate the total dissolved solids content of waters, to facilitate the selection of appropriate gear for efficient electrofishing, and to determine the velocity, stretch-out, dilution, and effective range of a solute over miles of a stream in conjunction with chemical reclamation operations. Applications of resistivity measurements on Appalachian streams are discussed.
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Nunkaew, Tomorn; Kantachote, Duangporn; Chaiprapat, Sumate; Nitoda, Teruhiko; Kanzaki, Hiroshi
2018-05-01
This study aimed to produce inexpensive 5-aminolevulinic acid (ALA) in a non-sterile latex rubber sheet wastewater (RSW) by Rhodopseudomonas palustris TN114 and PP803 for the possibility to use in agricultural purposes by investigating the optimum conditions, and applying of wood vinegar (WV) as an economical source of levulinic acid to enhance ALA content. The Box-Behnken Design experiment was conducted under microaerobic-light conditions for 96 h with TN114, PP803 and their mixed culture (1:1) by varying initial pH, inoculum size (% v/v) and initial chemical oxygen demand (COD, mg/L). Results showed that the optimal condition (pH, % inoculum size, COD) of each set to produce extracellular ALA was found at 7.50, 6.00, 2000 for TN114; 7.50, 7.00, 3000 for PP803; and 7.50, 6.00, 4000 for a mixed culture; and each set achieved COD reduction as high as 63%, 71% and 75%, respectively. Addition of the optimal concentration of WV at mid log phase at 0.63% for TN114, and 1.25% for PP803 and the mixed culture significantly increased the ALA content by 3.7-4.2 times (128, 90 and 131 μM, respectively) compared to their controls. ALA production cost could be reduced approximately 31 times with WV on the basis of the amount of levulinic acid used. Effluent containing ALA for using in agriculture could be achieved by treating the RSW with the selected ALA producer R. palustris strains under the optimized condition with a little WV additive.
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Improved Nitrogen Removal Effect In Continuous Flow A2/O Process Using Typical Extra Carbon Source
NASA Astrophysics Data System (ADS)
Wu, Haiyan; Gao, Junyan; Yang, Dianhai; Zhou, Qi; Cai, Bijing
2010-11-01
In order to provide a basis for optimal selection of carbon source, three typical external carbon sources (i.e. methanol, sodium acetate and leachate) were applied to examine nitrogen removal efficiency of continuous flow A2/O system with the influent from the effluent of grit chamber in the second Kunming wastewater treatment plant. The best dosage was determined, and the specific nitrogen removal rate and carbon consumption rate were calculated with regard to individual external carbon source in A2/O system. Economy and technology analysis was also conducted to select the suitable carbon source with a low operation cost. Experimental results showed that the external typical carbon source caused a remarkable enhancement of system nitrate degradation ability. In comparison with the blank test, the average TN and NH3-N removal efficiency of system with different dosing quantities of external carbon source was improved by 15.2% and 34.2%, respectively. The optimal dosage of methanol, sodium acetate and leachate was respectively up to 30 mg/L, 40 mg/L and 100 mg COD/L in terms of a high nitrogen degradation effect. The highest removal efficiency of COD, TN and NH3-N reached respectively 92.3%, 73.9% and 100% with methanol with a dosage of 30 mg/L. The kinetic analysis and calculation revealed that the greatest denitrification rate was 0.0107 mg TN/mg MLVSSṡd with sodium acetate of 60 mg/L. As to carbon consumption rate, however, the highest value occurred in the blank test with a rate of 0.1955 mg COD/mg MLVSSṡd. Also, further economic analysis proved leachate to be pragmatic external carbon source whose cost was far cheaper than methanol.
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Ajemian, Matthew J.; Jose, Philip D.; Froeschke, John T.; Wildhaber, Mark L.; Stunz, Gregory W.
2016-01-01
Although current assessments of shark population trends involve both fishery-independent and fishery-dependent data, the latter are generally limited to commercial landings that may neglect nearshore coastal habitats. Texas has supported the longest organized land-based recreational shark fishery in the United States, yet no studies have used this “non-traditional” data source to characterize the catch composition or trends in this multidecadal fishery. We analyzed catch records from two distinct periods straddling heavy commercial exploitation of sharks in the Gulf of Mexico (historical period = 1973–1986; modern period = 2008–2015) to highlight and make available the current status and historical trends in Texas’ land-based shark fishery. Catch records describing large coastal species (>1,800 mm stretched total length [STL]) were examined using multivariate techniques to assess catch seasonality and potential temporal shifts in species composition. These fishery-dependent data revealed consistent seasonality that was independent of the data set examined, although distinct shark assemblages were evident between the two periods. Similarity percentage analysis suggested decreased contributions of Lemon Shark Negaprion brevirostris over time and a general shift toward the dominance of Bull Shark Carcharhinus leucas and Blacktip Shark C. limbatus. Comparisons of mean STL for species captured in historical and modern periods further identified significant decreases for both Bull Sharks and Lemon Sharks. Size structure analysis showed a distinct paucity of landed individuals over 2,000 mm STL in recent years. Although inherent biases in reporting and potential gear-related inconsistencies undoubtedly influenced this fishery-dependent data set, the patterns in our findings documented potential declines in the size and occurrence of select large coastal shark species off Texas, consistent with declines reported in the Gulf of Mexico. Future management efforts should consider the use of non-traditional fishery-dependent data sources, such as land-based records, as data streams in stock assessments.
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Removal of slowly biodegradable COD in combined thermophilic UASB and MBBR systems.
Ji, M; Yu, J; Chen, H; Yue, P L
2001-09-01
Starch, cellulose and polyvinyl alcohol (PVA) are common substrates of the slowly biodegradable COD (SBCOD) in industrial wastewaters. Removal of the individual and mixed SbCOD substrates was investigated in a combined system of thermophilic upflow anaerobic sludge blanket (TUASB) reactor (55 degrees C) and aerobic moving bed biofilm reactor (MBBR). The removal mechanisms of the three SBCOD substrates were quite different. Starch-COD was almost equally utilized and removed in the two reactors. Cellulose-COD was completely (97-98%) removed from water in the TUASB reactor by microbial entrapment and sedimentation of the cellulose fibers. PVA alone was hardly biodegraded and removed by the combined reactors. However, PVA-COD could be removed to some extent in a binary solution of starch (77%) plus PVA (23%). The PVA macromolecules in the binary solution actually affected the microbial activity in the TUASB reactor resulting accumulation of volatile fatty acids, which shifted the overall COD removal from the TUASB to the MBBR reactor where SBCOD including PVA-COD was removed. Since the three SBCOD substrates were removed by different mechanisms, the combined reactors showed a better and more stable performance than individual reactors.
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Combined thermo-chemo-sonic disintegration of waste activated sludge for biogas production.
Kavitha, S; Yukesh Kannah, R; Yeom, Ick Tae; Do, Khac-Uan; Banu, J Rajesh
2015-12-01
In the present study, there was an investigation about the impact of a new combined thermo-chemo-sonic disintegration of waste activated sludge (WAS) on biodegradability. The outcome of sludge disintegration reveals that maximum Suspended Solids (SS) reduction and Chemical Oxygen Demand (COD) solubilization effectuated at a specific energy input of 5290.5kJ/kgTS, and was found to be 20%, 16.4%, 15% and 27%, 22%, and 20%, respectively for the three alkalis (NaOH, KOH, and Ca(OH)2). The conversion coefficient of the Volatile Suspended Solids (VSS) to product Soluble COD (SCOD), calculated by nonlinear regression modeling, was found to be 0.5530gSCOD/gVSS, 0.4587gSCOD/gVSS, and 0.4195gSCOD/gVSS for NaOH, KOH, and Ca(OH)2, respectively. In the biodegradability studies, the parameter evaluation provides an estimate of parameter uncertainty and correlation, and elucidates that there is no significant difference in biodegradability (0.413gCOD/gCOD, 0.367gCOD/gCOD, and 0.342gCOD/gCOD) for three alkalis (NaOH, KOH, and Ca(OH)2). Copyright © 2015 Elsevier Ltd. All rights reserved.
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Lin, Richen; Cheng, Jun; Yang, Zongbo; Ding, Lingkan; Zhang, Jiabei; Zhou, Junhu; Cen, Kefa
2016-08-01
Cassava ethanol wastewater (CEW) was subjected to sequential dark H2, photo H2 and CH4 fermentation to maximize H2 production and energy yield. A relatively low H2 yield of 23.6mL/g soluble chemical oxygen demand (CODs) was obtained in dark fermentation. To eliminate the inhibition of excessive NH4(+) on sequential photo fermentation, zeolite was used to remove NH4(+) in residual dark solution (86.5% removal efficiency). The treated solution from 5gCODs/L of CEW achieved the highest photo H2 yield of 369.7mL/gCODs, while the solution from 20gCODs/L gave the lowest yield of 259.6mL/gCODs. This can be explained that photo H2 yield was correlated to soluble metabolic products (SMPs) yield in dark fermentation, and specific SMPs yield decreased from 38.0 to 18.1mM/g CODs. The total energy yield significantly increased to 8.39kJ/gCODs by combining methanogenesis with a CH4 yield of 117.9mL/gCODs. Copyright © 2016 Elsevier Ltd. All rights reserved.
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Effects of dissolved oxygen on dye removal by zero-valent iron.
Wang, Kai-Sung; Lin, Chiou-Liang; Wei, Ming-Chi; Liang, Hsiu-Hao; Li, Heng-Ching; Chang, Chih-Hua; Fang, Yung-Tai; Chang, Shih-Hsien
2010-10-15
Effects of dissolved oxygen concentrations on dye removal by zero-valent iron (Fe(0)) were investigated. The Vibrio fischeri light inhibition test was employed to evaluate toxicity of decolorized solution. Three dyes, Acid Orange 7 (AO7, monoazo), Reactive Red 120 (RR120, diazo), and Acid Blue 9 (AB9, triphenylmethane), were selected as model dyes. The dye concentration and Fe(0) dose used were 100 mg L(-1) and 30 g L(-1), respectively. Under anoxic condition, the order for dye decolorization was AO7>RR120>AB9. An increase in the dissolved oxygen concentrations enhanced decolorization and chemical oxygen demand (COD) removal of the three dyes. An increase in gas flow rates also improved dye and COD removals by Fe(0). At dissolved oxygen of 6 mg L(-1), more than 99% of each dye was decolorized within 12 min and high COD removals were obtained (97% for AO7, 87% for RR120, and 93% for AB9). The toxicity of decolorized dye solutions was low (I(5)<40%). An increase in DO concentrations obviously reduced the toxicity. When DO above 2 mg L(-1) was applied, low iron ion concentration (13.6 mg L(-1)) was obtained in the decolorized AO7 solution. 2010 Elsevier B.V. All rights reserved.
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Energy-Aware Computation Offloading of IoT Sensors in Cloudlet-Based Mobile Edge Computing.
Ma, Xiao; Lin, Chuang; Zhang, Han; Liu, Jianwei
2018-06-15
Mobile edge computing is proposed as a promising computing paradigm to relieve the excessive burden of data centers and mobile networks, which is induced by the rapid growth of Internet of Things (IoT). This work introduces the cloud-assisted multi-cloudlet framework to provision scalable services in cloudlet-based mobile edge computing. Due to the constrained computation resources of cloudlets and limited communication resources of wireless access points (APs), IoT sensors with identical computation offloading decisions interact with each other. To optimize the processing delay and energy consumption of computation tasks, theoretic analysis of the computation offloading decision problem of IoT sensors is presented in this paper. In more detail, the computation offloading decision problem of IoT sensors is formulated as a computation offloading game and the condition of Nash equilibrium is derived by introducing the tool of a potential game. By exploiting the finite improvement property of the game, the Computation Offloading Decision (COD) algorithm is designed to provide decentralized computation offloading strategies for IoT sensors. Simulation results demonstrate that the COD algorithm can significantly reduce the system cost compared with the random-selection algorithm and the cloud-first algorithm. Furthermore, the COD algorithm can scale well with increasing IoT sensors.
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Darajeh, Negisa; Idris, Azni; Fard Masoumi, Hamid Reza; Nourani, Abolfazl; Truong, Paul; Rezania, Shahabaldin
2017-05-04
Artificial neural networks (ANNs) have been widely used to solve the problems because of their reliable, robust, and salient characteristics in capturing the nonlinear relationships between variables in complex systems. In this study, ANN was applied for modeling of Chemical Oxygen Demand (COD) and biodegradable organic matter (BOD) removal from palm oil mill secondary effluent (POMSE) by vetiver system. The independent variable, including POMSE concentration, vetiver slips density, and removal time, has been considered as input parameters to optimize the network, while the removal percentage of COD and BOD were selected as output. To determine the number of hidden layer nodes, the root mean squared error of testing set was minimized, and the topologies of the algorithms were compared by coefficient of determination and absolute average deviation. The comparison indicated that the quick propagation (QP) algorithm had minimum root mean squared error and absolute average deviation, and maximum coefficient of determination. The importance values of the variables was included vetiver slips density with 42.41%, time with 29.8%, and the POMSE concentration with 27.79%, which showed none of them, is negligible. Results show that the ANN has great potential ability in prediction of COD and BOD removal from POMSE with residual standard error (RSE) of less than 0.45%.
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Fluctuation of the Water Environmental Carrying Capacity in a Huge River-Connected Lake
Wang, Hua; Zhou, Yiyi; Tang, Yang; Wu, Mengan; Deng, Yanqing
2015-01-01
A new method, with the non-fully mixed coefficient (NFMC) considered, was put forward to calculate the water environmental carrying capacity (WECC) for huge river-connected lakes, of which the hydrological conditions always vary widely during a year. Poyang Lake, the most typical river-connected lake and the largest freshwater lake in China, was selected as the research area. Based on field investigations and numerical simulation, the monthly pollutant degradation coefficients and non-fully mixed coefficients of different lake regions were determined to explore the WECCs of COD, TN and TP of Poyang Lake in a common water year. It was found that under the hydrological conditions of a common water year the total WECCs of COD, TN and TP in the lake were respectively 181.9 × 104 t, 33.3 × 104 t and 1.86 × 104 t. Due to the varied lake water volume and self-purification ability, an evident temporal fluctuation of WECCs in Poyang Lake was observed. The dry seasons were characterized by a higher NFMCs but lower WECCs owing to the lower water level and degradation ability. Variation coefficients of COD and TN WECC were close to each other, of which the average level was about 58.5%, a little higher than that of TP. PMID:25830284
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Tauchman, Jiří; Císařová, Ivana; Stěpnička, Petr
2014-01-28
1'-Diphenylphosphino-1-{[(2-(methylthio)ethyl)amino]carbonyl}ferrocene (1), accessible via amidation of 1'-(diphenylphosphino)ferrocene-1-carboxylic acid (Hdpf) with 2-(methylthio)ethylamine, reacts with [PdCl2(cod)] (cod = cycloocta-1,5-diene) at a 1 : 1 metal-to-ligand ratio to give trans-[PdCl2(1-κ(2)P,S)] (trans-2) as the sole product. A similar reaction with [PtCl2(cod)] affords a mixture of cis- and trans-[PtCl2(1-κ(2)P,S)] (cis- and trans-3), which can be separated by fractional crystallisation. Complexation reactions performed with 2 equiv. of the ligand are less selective, yielding mixtures of the expected bis-phosphine complexes (i.e., trans-[PdCl2(1-κP)2], or a mixture of cis- and trans-[PtCl2(-κP)2]) with the respective monophosphine complexes. The structures of 1, trans-2, cis-3 and trans-3 determined by X-ray diffraction demonstrate the ability of the title ligand to act as a flexible cis- or trans-P,S-chelate donor (the ligand bite angles are 174.03(2)/173.05(2)° for trans-2/3 and 92.86(2)° for cis-3).
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Earth observations taken from shuttle orbiter Atlantis during STS-84 mission
1997-07-09
STS084-703-003 (15-24 May 1997) --- Cape Cod extends 105 kilometers (65 miles) into the Atlantic Ocean. To the south of Cape Cod are the islands of Martha's Vineyard (west) and Nantucket (east). The city of Boston can be seen surrounding the bay above the "hook" on Cape Cod. To the south are the cities of New Bedford on Buzzards Bay, and Providence, Rhode Island. The Cape Cod Canal is an artificial waterway that connects Buzzards Bay and Cape Cod Bay. The waterway is 28 kilometers (17.5 miles) and does not contains locks. The canal was built to shorten the distance over water between New York City and Boston. In 1620 the Pilgrims landed at Provincetown, on the upper tip of Cape Cod, before they proceeded to Plymouth.
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Tawfik, Ahmed; Wahab, Rifaat Abdel; Al-Asmer, Azza; Matary, Fatma
2011-08-01
Grey wastewater (GW) treatment via down-flow hanging sponge (DHS) system was the subject of the study. The reactor was operated at different hydraulic retention times (HRTs) of 11.7, 5.8 and 2.9 h, corresponding to organic loading rates (OLRs) of 1.9, 3.6 and 6.8 kgCOD/m3 day, respectively. The results obtained revealed that decreasing the HRT from 11.7 to 2.9 h negatively affected on the performance of the DHS system. COD(total), COD(soluble), COD(particulate) and detergent removal efficiency were reduced from 96 ± 2.4 to 90 ± 2.3%, from 83 ± 10 to 69 ± 8%, from 98 ± 2 to 94 ± 3% and from 96 ± 12 to 88 ± 6.9%, respectively. However, the removal efficiency of the distinguished COD fractions and detergent remained unaffected when decreasing the HRT from 11.7 to 5.8 h. The DHS system provided a removal efficiency of 95 ± 1% for COD(total), 79 ± 8% for COD(soluble), 98 ± 2 for COD(particulate) and 94.7% for detergent at an HRT of 5.8 h. Based on these results, it is recommended to operate such a system at an HRT of 5.8 h and OLR not exceeding 3.6 kgCOD/m3 day for producing an effluent quality complying for reuse in unrestricted irrigation purposes. The removal of TKj-N and nitrification efficiency in the DHS system was significantly affected by increasing the OLR from 1.9 to 3.6 kgCOD/m3 day and from 3.6 to 6.8 kgCOD/m3 day. At an OLR of 1.9 kgCOD/m3 day, the DHS system removed 80 ± 12% of TKj-N and 91 ± 22% of ammonia which is significantly higher than that at an OLR of 3.6 (58.5 ± 13%) and 6.8 kgCOD/m3 day (26.8 ± 16%). Similar results were recorded for the removal of total coliform (TC), viz., the efficiencies dropped for TC from 99.8 ± 0.2 to 99.4 ± 0.8% and from 99.4 ± 0.8 to 90.0 ± 7.6%, respectively. DHS profile results showed that the major part of COD was removed in the upper portion of the system while the nitrification process was taken place in the lower part of the DHS system at OLR of 1.9 kgCOD/m3 day and HRT of 11.7 h.