WorldWideScience
 
 
1

Statistical aspects of fish stock assessment  

DEFF Research Database (Denmark)

Fish stock assessments are conducted for two main purposes: 1) To estimate past and present fish abundances and their commercial exploitation rates. 2) To predict the consequences of different management strategies in order to ensure a sustainable fishery in the future. This thesis concerns statistical aspects of fish stocks assessment, which includes topics such as time series analysis, generalized additive models (GAMs), and non-linear state-space/mixed models capable of handling missing data and a high number of latent states and parameters. The aim is to improve the existing methods for stock assessment by application of state-of-the-art statistical methodology. The main contributions are presented in the form of six research papers. The major part of the thesis deals with age-structured assessment models, which is the most common approach. Conversion from length to age distributions in the catches is a necessary step in age-based stock assessment models. For this purpose, GAMs and continuation ratio logits are combined to model the probability of age as a smooth function of length and spatial coordinates, which constitutes an improvement over traditional methods based on area-stratification. GAMs and delta-distributions are applied for the calculation of indices of abundance from trawl survey data, and different error structures for these are investigated. Two extensions to the state-space approach to age-structured stock assessment modelling are presented. The first extension introduces multivariate error distributions on survey catch-at-age data. The second extension is an integrated assessment model for overlapping sub-stocks subject to joint exploitation in the area of overlap. Estimation and inference is carried out using maximum likelihood. Finally, a biomass dynamic model based on stochastic differential equations is presented. This work extends the classical approaches to biomass modelling by incorporating observation errors on the catches, and allowing for missing and non-equidistant samples in time.

Berg, Casper Willestofte

2013-01-01

2

Consequences of fish behaviour for stock assessment Fish behaviour in relation to fishing operations  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The influence of fish behaviour on the most common stock assessment methods is reviewed. Fish behaviour may be divided into four major groups : habitat selection, aggregation pattern, avoidance reactions, and learning. Examples of temperate and tropical species are presented. (Résumé d'auteur)

Fréon, Pierre; Gerlotto, François; Misund, O.A.

3

STANDING STOCK OF DEMERSAL FISH ASSESSMENT IN SOUTHERN PART OF SOUTH CHINA SEA  

Directory of Open Access Journals (Sweden)

Full Text Available Demersal fish assessment is prerequisite for optimal fishing. In this paper, standing stock of demersal fish in southern part of South China Sea was determined by swept area method. The research was carried out by research vessel SEAFDEC on 18 – 30 June 2005. The catch of fish was obtained from 18 in-situ station use bottom trawl. There were found 154 species and 38 563 individual, respectively. The Leiognathus bindus was dominant species at fishing operation. Catch per unit area (CPUA) was ranged from 62.99 to 748.57 kg km-² and averaged 420.32 kg km-². The overall catch rate ranged 5.6 to 121.97 kg hr-1and averaged 50.54 kg hr-1. The standing stock of demersal fish in survey area was 124 560 ton.

Julius A.N Masrikat

2012-01-01

4

Multicriteria assessment in restoring migratory fish stocks in the river Iijoki; Monitavoitearviointi Iijoen vaelluskalakantojen palauttamisen tukena  

Energy Technology Data Exchange (ETDEWEB)

The Iijoki is one of Finland's most important former salmon rivers. Construction of multiple main stem dams on the river in the 1960s effectively blocked the migration corridors of migratory fish. Suitable spawning and nursery habitats above the dams span an estimated 600-800 hectares. With riverside residents are very much in favour of the return of migratory fish, watershed planning for this has been set as a target. Such measures are rendered urgent by the fact that there is still a possibility of replenishing the Iijoki's own salmon stock, thereby restoring the fishes' natural lifecycle and natural selection. This report has been completed as part of the project 'The return of migratory fish to the River Iijoki (2008-2010)', where the main object was reconciling the target of enhancing the natural life cycle of migratory fish with the continued generation of hydropower. Under a multicriteria assessment, various alternatives and measures for improving migratory fish stocks were clarified and their desirability, costs and benefits systematically and transparently evaluated. Furthermore, interest groups' views of the three options and their effects (as distinct from the expert evaluation) were clarified with the help of computer aided interviews. The alternatives were transferring salmon above the main stem dams and two fish-ladder options. The multicriteria assessment viewed the construction of fish ladders, alongside other large-scale support measures, as the best option. Based on all of the criteria applied in a cost-benefit analysis, the stock transfer alternative was the most economically viable, because its net product value was positive in all cases. The fish ladder options were the most expensive due to the construction costs involved, but they also provided the greatest benefits. Above all, fish ladder construction is supported by the fact that it would return migratory fish to their natural lifecycle and attain the EU's watershed planning objectives. In addition, its effects on local identity, fishing tourism and the attractiveness of the area speak in its favour. With respect to the return of migratory fish, the greatest uncertainties lie in developments in the state of the Baltic Sea and the regulation of fishing. A multicriteria assessment helped the respondents and stakeholders achieve a better overall understanding of the planning situation and the various parties' objectives and views. This assisted in creating common ground in building a co-management model to establish further measures for the return of migrant fish. (orig.)

Karjalainen, T.P.; Rytkoenen, A.-M.; Marttunen, M.; Maeki-Petaeys, A.; Autti, O.

2011-05-15

5

Statistical modelling of fish stocks  

DEFF Research Database (Denmark)

In this thesis uncertainty associated with stock assessment has been considered, especially uncertainty associated with the input data to the model. The thesis provides new approaches to analyse the sources of variation in the input data and their magnitude, and an alternative approach for modelling the dynamics of a fish population is suggested. A new approach is introduced to analyse the sources of variation in age composition data, which is one of the most important sources of information in the cohort based models for estimation of stock abundancies and mortalities. The approach combines the continuation-ratio logits, which can take the ordinal and multinomial characteristics of the response into account, and the generalized linear mixed models, which allow for fixed as well as random effects to be analysed. Catch at age data and the associated uncertainties have been estimated, by separating the statistical analysis into separate analyses of the various data sources. The results were combined into estimates of the catch at age data and the associated uncertainties for the sandeel landings from the North Sea in 1989 and 1991. An overview of age-structured stock assessment models is given and it is argued that an approach utilising stochastic differential equations might be advantagous in fish stoch assessments.

Kvist, Trine

1999-01-01

6

Reversal of fish stock decline in the Northeast Atlantic.  

UK PubMed Central (United Kingdom)

Analyses of global fish stocks paint a mixed picture of success, with some holding fishery management responsible for the poor status of many stocks [1-3] or predicting widespread collapse [1, 4]. Some suggest a stable [5] or improving situation [6] in certain jurisdictions. The debate is particularly polarized in the European Union, where the Common Fisheries Policy (CFP) has been criticized for failing to protect stocks [2, 7-10], while others argue that a rebuilding process is underway [11, 12]. We show that substantial change in stock trends occurred in the area around the turn of the century: since then, the fishing pressure (as measured by the exploitation rate) has reduced continuously and there have been increases in biomass, demonstrating the potential for stock recovery. In 2011, for the first time, the majority of assessed stocks, where reference points are defined, were fished sustainably. The reductions in fishing pressure were associated with declines in fishing effort. The last reform of the CFP, in 2002, introduced effort control as part of more enforceable management measures, which were also based on longer-term plans. Further reforms to the CFP are currently being developed, so it is important, when correcting its weaknesses, to also acknowledge and build on the success of a major reduction in the fishing pressure on European fish stocks.

Fernandes PG; Cook RM

2013-08-01

7

Fish stock conservation measures and the Irish fishing industry  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The decline in fish stocks is well documented and numerous efforts are in place to preserve and rebuild stocks. While conservation programmes have the potential to improve profitability, this usually will not occur before contraction in the fishery (in landings, incomes, employment, etc.). Conservat...

Curtis, John A.

8

PIXE analysis of fish otoliths. Application to fish stock discrimination  

Energy Technology Data Exchange (ETDEWEB)

PIXE was adopted to analyze trace elements in otoliths of Japanese flounder to discriminate among several local fish stocks. The otoliths were removed from samples caught at five different sea areas along with the coast of the Sea of Japan: Akita, Ishikawa, Kyoto (2 stations), and Fukuoka. Besides calcium as main component, strontium, manganese, and zinc were detected. Especially Sr concentrations were different among 4 areas except between 2 stations in Kyoto. It suggested that the fish in the 2 stations in Kyoto were the same stock differed to the others. (author)

Arai, Nobuaki; Sakamoto, Wataru [Kyoto Univ., Kyoto (Japan). Lab. of Fisheries and Environmental Oceanography; Tateno, Koji; Yoshida, Koji

1996-12-31

9

PIXE analysis of fish otoliths. Application to fish stock discrimination  

International Nuclear Information System (INIS)

PIXE was adopted to analyze trace elements in otoliths of Japanese flounder to discriminate among several local fish stocks. The otoliths were removed from samples caught at five different sea areas along with the coast of the Sea of Japan: Akita, Ishikawa, Kyoto (2 stations), and Fukuoka. Besides calcium as main component, strontium, manganese, and zinc were detected. Especially Sr concentrations were different among 4 areas except between 2 stations in Kyoto. It suggested that the fish in the 2 stations in Kyoto were the same stock differed to the others. (author).

1996-01-01

10

Fish stocking density impacts tank hydrodynamics  

DEFF Research Database (Denmark)

The effect of stocking density upon the hydrodynamics of a circular tank, configured in a recirculation system, was investigated. Red drums Sciaenops ocellatus of approximately 140 g wet weight, were stocked at five rates varying from 0 to 12 kg m-3. The impact of the presence of fish upon tank hydrodynamics was established using in-tank-based Rhodamine WT fluorometry at a flow rate of 0.23 l s-1 (tank exchange rate of 1.9 h-1). With increasing numbers of animals, curvilinear relationships were observed for dispersion coefficients and tank mixing times. Stocking densities of 3, 6, 9 and 12 kg m-3 resulted in a 0.2-, 0.5-, 2.4-, and 3.2-fold decrease in mixing time relative to that observed for empty tanks (Pb0.001). Udgivelsesdato: APR 28

Rasmussen, Michael R.; Lunger, Angela

2006-01-01

11

ASSESSMENT OF INFLUENCE INFLATION STOCKS  

Directory of Open Access Journals (Sweden)

Full Text Available Inflation, one of the most complex and controversial issues of economy, was in some countries and periodswhat put in danger the development and progress of the economy. Not negligible at all when it comes to its influenceupon the financial position and the economic entities high standards, inflation is a problem for accounting. A researchregarding inflation influences on accounting involves an analysis of the negative and positive effects of infl ation on theeconomic items evaluation. In this context, it must be highlighted the limits of using the historical costs and theadvantages of using the fair values for evaluation as basis for evaluation. Regarding the property elements, stocks arethose that fallow fix assets in term of degree of liquidity. In practice, we often encounter situations when, from a periodto another, sensitive growth of stocks prices are registered with considerable influence in terms of resumption ofproduction and future production costs. In the paper it is outlined the inflation’s impact upon the stock evaluation intwo different moments: when stocks exit administration and when the financial year closes. The comparative studyregarding application the accounting methods a dapted to stock inflation highlights both the advantages anddisadvantages of each method. The assessment model of inflation influence on stocks presented in the paper it is beinganalyzed in conjunction with the stocks speed rotation

Mihaela TULVINSCHI; Mariana VLAD

2009-01-01

12

The Stock Book 2012 : Annual Review of Fish Stocks in 2012 with Management Advice for 2013  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The Stock Book is the principal annual publication of the Marine Institute's Fisheries Ecosystems Advisory Services (FEAS). Its purpose is to provide the latest impartial scientific advice on the commercially exploited fish stocks of interest to Ireland. The Stock Book is used by the Department of A...

Marine Institute

13

The Stock Book 2011 : Annual Review of Fish Stocks in 2011 with Management Advice for 2012  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The Stock Book is the principal annual publication of the Marine Institute's Fisheries Science Services (FSS). Its purpose is to provide the latest impartial scientific advice on the commercially exploited fish stocks of interest to Ireland. The Stock Book is used by the Department of Agriculture, M...

Marine Institute

14

Fish otoliths analysis by PIXE: application to stock discrimination  

Energy Technology Data Exchange (ETDEWEB)

Fish otoliths are continuously deposited from fish birth to its death along with encoding environmental information. In order to decode the information, PIXE was adopted as trace elemental analysis of the otoliths. Strontium to calcium concentration ratios of red sea bream otoliths varied among rearing stations. The Sr/Ca ratios of Lake Biwa catfishes also varied between male and female and among fishing grounds. The PIXE analysis was applied to the fish stock discrimination. (author)

Arai, Nobuaki; Takai, Noriyuki; Sakamoto, Wataru [Kyoto Univ. (Japan). Faculty of Agriculture; Yoshida, Koji; Maeda, Kuniko

1996-12-31

15

Fish otoliths analysis by PIXE: application to stock discrimination  

International Nuclear Information System (INIS)

Fish otoliths are continuously deposited from fish birth to its death along with encoding environmental information. In order to decode the information, PIXE was adopted as trace elemental analysis of the otoliths. Strontium to calcium concentration ratios of red sea bream otoliths varied among rearing stations. The Sr/Ca ratios of Lake Biwa catfishes also varied between male and female and among fishing grounds. The PIXE analysis was applied to the fish stock discrimination. (author).

1996-01-01

16

Integrating genetic and parasitological approaches in the frame of multidisciplinary fish stock analysis.  

Science.gov (United States)

To assess fish stocks boundaries and state, the tools of population genetics have been widely used, contributing to the evaluation of relevant parameters such as the identification of stock boundaries, the assessment of gene flow and the estimation of effective population size. Also, increasing evidences show that the monitoring of the genetic diversity level is a reliable method to check the status of fish stocks. However, genetics cannot answer all the questions. For example, in high gene flow species the genetic approach could have not enough resolution to identify stock limits, while the use of parasites as biological tags could provide insights into stock structure. Even better, the so-called holistic approach, applying simultaneously a wide range of complementary techniques, is the only one considered able to provide a reliable and complete picture of fish stocks and to address a sustainable exploitation of marine resources. The work will present some examples from multidisciplinary studies concerning commercially relevant species with different biological features: the demersal European hake (Merluccius merluccius), the small pelagic horse mackerel (Trachurus trachurus) and the large pelagic swordfish (Xiphias gladius). In all these case studies merging genetic, parasitological and environmental data helped to reveal the real patterns of stocks structure. PMID:18410069

Cimmaruta, R; Mattiucci, S; Nascetti, G

2007-09-01

17

Rebuilding EU fish stocks and fisheries, a process under way?  

DEFF Research Database (Denmark)

As a signatory to the World Summit on Sustainable Development (WSSD), the European Union (EU) has made a commitment to maintain or restore fish stocks to levels that can produce the maximum sustainable yield (MSY), and where possible not later than 2015. So how has the EU's Common Fisheries Policy (CFP) fared in trying to achieve this objective? The development of the status of 41 commercially exploited fish stocks from the North East Atlantic, North Sea and Baltic Sea (FAO Area 27) was analysed together with the economic performance of the fleets exploiting those stocks. The analyses indicate that the exploitation status for many of the stocks has greatly improved during the last 10 years while the economic performance of the fleets over the same period has been highly variable. The main economic indicators (gross value added (GVA) and operating cash flow (OCF)) have gradually improved at a time when the general economic situation, which has a great influence on the markets, costs and purchase power, has worsened. While recognizing that much remains to be done to achieve the objective of the WSSD, the analyses indicate that actions implemented in the last decade under the CFP have led to an improvement in the status of many commercially important fish stocks and their fleets towards levels that are closer to those producing MSY.

Cardinale, M.; Dörner, H.

2013-01-01

18

On the interplay of environmental changes and fishing pressure in exploited fish stocks  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Fish in many exploited stocks grow faster and mature earlier at either larger or smaller sizes in comparisonto pre-exploitation periods. These changes can be driven by both genetic and phenotypic responses.At the same time, these stocks may adjust to other changes of the environment such as increasi...

Boukal, David S.; de Roos, Andre M.; Persson, Lennart; Heino, Mikko

19

77 FR 3450 - Guidelines for Assessing Marine Mammal Stocks  

Science.gov (United States)

...Guidelines for Assessing Marine Mammal Stocks AGENCY: National Marine Fisheries Service...guidelines for preparing marine mammal stock assessment reports (SARs). [[Page...guidelines for preparing marine mammal stock assessment reports are contained in...

2012-01-24

20

Dynamics and management of stage-structured fish stocks.  

UK PubMed Central (United Kingdom)

With increasing fishing pressures having brought several stocks to the brink of collapse, there is a need for developing efficient harvesting methods that account for factors beyond merely yield or profit. We consider the dynamics and management of a stage-structured fish stock. Our work is based on a consumer-resource model which De Roos et al. (in Theor. Popul. Biol. 73, 47-62, 2008) have derived as an approximation of a physiologically-structured counterpart. First, we rigorously prove the existence of steady states in both models, that the models share the same steady states, and that there exists at most one positive steady state. Furthermore, we carry out numerical investigations which suggest that a steady state is globally stable if it is locally stable. Second, we consider multiobjective harvesting strategies which account for yield, profit, and the recovery potential of the fish stock. The recovery potential is a measure of how quickly a fish stock can recover from a major disturbance and serves as an indication of the extinction risk associated with a harvesting strategy. Our analysis reveals that a small reduction in yield or profit allows for a disproportional increase in recovery potential. We also show that there exists a harvesting strategy with yield close to the maximum sustainable yield (MSY) and profit close to that associated with the maximum economic yield (MEY). In offering a good compromise between MSY and MEY, we believe that this harvesting strategy is preferable in most instances. Third, we consider the impact of harvesting on population size structure and analytically determine the most and least harmful harvesting strategies. We conclude that the most harmful harvesting strategy consists of harvesting both adults and juveniles, while harvesting only adults is the least harmful strategy. Finally, we find that a high percentage of juvenile biomass indicates elevated extinction risk and might therefore serve as an early-warning signal of impending stock collapse.

Meng X; Lundström NL; Bodin M; Brännström Å

2013-01-01

 
 
 
 
21

A definition of depletion of fish stocks  

Science.gov (United States)

Attention was focused on the need of a common and better understanding of the term depletion as applied to the fisheries in order to eliminate if possible the existing inexactness of thought on the subject. Depletion has been confused at various times with at least ten different ideas associated with it but which, as has has heen pointed out, are not synonymous at all. In defining depletion we must recognize that the term represents a condition and must not he confounded with the cause (overfishing) that leads to this condition or with the symptoms that identify it. Depletion was defined as a reduction, through overfishing, in the level of abundance of the exploitable segment of a stock that prevents the realization of the maximum productive capacity.

Van Oosten, John

1949-01-01

22

Duck Valley Reservoirs Fish Stocking and O&M, Annual Progress Report 2007-2008.  

Science.gov (United States)

The Duck Valley Reservoirs Fish Stocking and Operations and Maintenance Project (DV Fisheries) is an ongoing resident fish program that serves to partially mitigate the loss of anadromous fish that resulted from downstream construction of the federal hydr...

C. Perugini J. Sellman

2009-01-01

23

Frequency and intensity of productivity regime shifts in marine fish stocks.  

Science.gov (United States)

Fish stocks fluctuate both in abundance and productivity (net population increase), and there are many examples demonstrating that productivity increased or decreased due to changes in abundance caused by fishing and, alternatively, where productivity shifted between low and high regimes, entirely unrelated to abundance. Although shifts in productivity regimes have been described, their frequency and intensity have not previously been assessed. We use a database of trends in harvest and abundance of 230 fish stocks to evaluate the proportion of fish stocks in which productivity is primarily related to abundance vs. those that appear to manifest regimes of high or low productivity. We evaluated the statistical support for four hypotheses: (i) the abundance hypothesis, where production is always related to population abundance; (ii) the regimes hypothesis, where production shifts irregularly between regimes that are unrelated to abundance; (iii) the mixed hypothesis, where even though production is related to population abundance, there are irregular changes in this relationship; and (iv) the random hypothesis, where production is random from year to year. We found that the abundance hypothesis best explains 18.3% of stocks, the regimes hypothesis 38.6%, the mixed hypothesis 30.5%, and the random hypothesis 12.6%. Fisheries management agencies need to recognize that irregular changes in productivity are common and that harvest regulation and management targets may need to be adjusted whenever productivity changes. PMID:23322735

Vert-pre, Katyana A; Amoroso, Ricardo O; Jensen, Olaf P; Hilborn, Ray

2013-01-15

24

75 FR 6058 - Federal Sport Fish Restoration; California Department of Fish and Game Fish Hatchery and Stocking...  

Science.gov (United States)

...13007 to the California Fish and Game Code (FGC 13007), which established annual minimum...purposes. Per CDFG's implementation plan for FGC 13007, funding for the stocking program...Program. To expedite Program changes due to FGC 13007, the court-ordered...

2010-02-05

25

The CUSUM out-of-control table to monitor changes in fish stock status using many indicators  

Digital Repository Infrastructure Vision for European Research (DRIVER)

One method to assess fish stocks using a suite of indicators is the traffic light approach. In this approach, the time series of the different indicators are mapped on a common colour scale to highlight alerts that occur when indicators cross reference limit values. Until now, however, the procedure...

Petitgas Pierre

26

The effect of fish impingement at Sizewell 'A' Power Station, Suffolk, on North Sea fish stocks  

International Nuclear Information System (INIS)

Samples collected from the cooling water intake screens of Sizewell 'A' power station over a 12 month period contained 73 species of fish. Of these, only 20 species were present on more than 50% of sampling dates and only 7 commercially exploited species were caught in quantities of more than a few hundred over the year; namely sprat, herring, cod, whiting, sole, dab and plaice. These species formed the basis of analysis of the impact of the Power Station on commercial species. Commercial species found in the Sizewell area are part of major North Sea stocks. The impact of the losses due to the Power Station is spread over these stocks, hence the effect is minimal. The mortality rate caused by the Power Station is one thousandth to one hundred-thousandth, depending on species, of that caused by commercial fishing and the effect is less than that of a small, inefficient commercial trawler. (author).

1988-01-01

27

The Effect of Marine Fish Biomass Stock Reduction to Fishers Revenue (A Case Study of Sardinella Lemuru Fisheries on Bali Strait)  

Directory of Open Access Journals (Sweden)

Full Text Available Stock assessment studies indicate that Sardinela Lemuru fisheries of Bali strait have been overfishing. This research attempts to (1) Identify the effect of biomass stock reduction to fishers revenue per trip, (2) Analyze the economic feasibility study for purse seine of Muncar, Banyuwangi. System Dynamic approach is used for simulation modeling. Simulation output shows a strong correlation between fish stock reduction and fisher revenue. The growth of fishing effort per year results on the reduction of catch per unit effort and total catch per year. Feasibility study concludes that purse seine (30 GT) which operates 120 trips per year is no longer a profitable business since 2020.

Ratna Purwaningsih; Sjarief Widjaja; Sri Gunani Partiwi

2011-01-01

28

Effects of Marine Protected Areas on Overfished Fishing Stocks with Multiple Stable States.  

UK PubMed Central (United Kingdom)

Marine protected areas (MPAs) have attracted much attention as a tool for sustainable fisheries management, restoring depleted fisheries stocks and maintaining ecosystems. However, even with total exclusion of fishing effort, depleted stocks sometimes show little or no recovery over a long time period. Here, using a mathematical model, we show that multiple stable states may hold the key to understanding the tendency for fisheries stocks to recover because of MPAs. We find that MPAs can have either a positive effect or almost no effect on the recovery of depleted fishing stocks, depending on the fish migration patterns and the fishing policies. MPAs also reinforce ecological resilience, particularly for migratory species. In contrast to previous reports, our results show that MPAs have small or sometimes negative effects on the recovery of sedentary species. Unsuitable MPA planning might result in low effectiveness or even deterioration of the existing condition.

Takashina N; Mougi A

2013-09-01

29

Water Quality, Stocking Density and Parasites of Freshwater Fish in Four Selected Areas of Bangladesh  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Stocking density, water quality (depth, temperature, dissolved oxygen, pH, total ammonia, hardness as CaCO3 and total alkalinity) and parasites of fishes were investigated in four selected areas (Bogra, Chandpur, Jessore and Mymensingh) for a period of three years. Stocking density varied...

A.N.H. Banu; M.H. Khan

30

Fish stocking density induced growth responses of some biogeochemical cycling bacterial population  

Directory of Open Access Journals (Sweden)

Full Text Available Experiment was performed to ascertain the effect of fish stocking density on population growth performance of some biogeochemical cycling bacteria in carp culture system. Advanced fry of Catla catla L., Labeo bata Ham. and Cyprinus carpio L. were introduced into tanks @ 8, 13, 16 and 32 fry tank-1 maintaining the ratio of C. catla -2 : L. bata -3 : C. carpio -3. Each tank was fertilized with mixed fertilizer @ 200 g week-1 during the rearing period of 150 days. Water samples were collected for examination of bacterial population, primary productivity and water quality parameters at weekly and biweekly intervals. Growth of fish was recorded at regular intervals. Statistical analysis of collected data was done by ANOVA and LSD for separation of mean (P < 0.05). Bacterial growth rate and productivity tended to rise with increasing stocking density showing maximum at stocking density 32 fry tank-1 whereas, fish growth exhibited an increasing trend upto stocking density 16 fry tank-1 and declined in further increment of fish density. Stocking density dependent growth efficiency of different bacteria (heterotrophic bacteria, cellulose decomposing bacteria, denitrifying bacteria and phosphate solubilizing bacteria) varied from 18 to 62.7%, 45 to 140%, 61 to 238% and 79 to 382% in stocking density 8, 13, 16 and 32 fry tank-1 , respectively. Results clearly revealed that higher stocking density of fishes liberates higher quantity of faecal matter containing proportionately greater amount of nutrients having more scope for bacteria to act upon the faecal matter resulting in higher bacterial population and productivity in one hand and fish growth inhibition due to stressful and uncongenial environmental condition developed by means of heavy nutrient load on the other hand. Therefore, it may be concluded that stocking density influencing the growth of biogeochemical cycling bacterial population in fish culture system.

J. N. Bhakta; J. K. Biswas; P. Bhakta; Y. Munekage; B. B. Jana

2010-01-01

31

Shellfish Stocks and Fisheries Review 2011: An assessment of selected stocks  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This review presents information on the status of selected shellfish stocks in Ireland. In addition data on the fleet (<13m) and landings for all species of shellfish (excluding Nephrops) are presented. The intention of the annual reviews is to present stock assessment and scientific advice for shel...

Marine Institute; Bord Iascaigh Mhara

32

Resident Fish Stock above Chief Joseph and Grand Coulee Dams; 2002 Annual Report.  

Energy Technology Data Exchange (ETDEWEB)

In 1980, the United States Congress enacted the Northwest Power Planning and Conservation Act (PL 96-501, 1980), which established the Northwest Power and Conservation Council (NPCC), formerly the Northwest Power Planning Council. The NPCC was directed by Congress to develop a regional Power Plan and also the Columbia River Basin Fish and Wildlife Program (FWP) to restore or replace losses of fish caused by construction and operation of hydroelectric dams in the Columbia River Basin. In developing the FWP, Congress specifically directed NPCC to solicit recommendations for measures to be included in the Program from the region's fish and wildlife agencies and Indian tribes. All measures adopted by the Council were also required to be consistent with the management objectives of the agencies and tribes [Section 4.(h)(6)(A)], the legal rights of Indian tribes in the region [Section 4.(h)(6)(D)] and be based upon and supported by the best available scientific knowledge [Section 4.(h)(6)(B)]. The Resident Fish Stock Status above Chief Joseph and Grand Coulee Dams Project, also known as the Joint Stock Assessment Project (JSAP) specifically addresses NPPC Council measure 10.8B.26 of the 1994 program. The Joint Stock Assessment Project is a management tool using ecosystem principles to manage artificial fish assemblages and native fish in altered environments existing in the Columbia River System above Chief Joseph and Grand Coulee Dams (Blocked Area). A three-phase approach of this project will enhance the fisheries resources of the Blocked Area by identifying data gaps, filling data gaps with research, and implementing management recommendations based on research results. The Blocked Area fisheries information is housed in a central location, allowing managers to view the entire system while making decisions, rather than basing management decisions on isolated portions of the system. The JSAP is designed and guided jointly by fisheries managers in the Blocked Area. The initial year of the project (1997) identified the need for a central data storage and analysis facility, coordination with the StreamNet project, compilation of Blocked Area fisheries information, and a report on the ecological condition of the Spokane River System. These needs were addressed in 1998 by acquiring a central location with a data storage and analysis system, coordinating a pilot project with StreamNet, compiling fisheries distribution data throughout the Blocked Area, identifying data gaps based on compiled information, and researching the ecological condition of the Spokane River. In order to ensure that any additional information collected throughout the life of this project will be easily stored and manipulated by the central storage facility, it was necessary to develop standardized methodologies between the JSAP fisheries managers. Common collection and analytical methodologies were developed in 1999. In 1999, 2000, and 2001 the project began addressing some of the identified data gaps throughout the Blocked Area. Data collection of established projects and a variety of newly developed sampling projects are ongoing. Projects developed and undertaken by JSAP fisheries managers include investigations of the Pend Orielle River and its tributaries, the Little Spokane River and its tributaries, and water bodies within and near the Spokane Indian Reservation. Migration patterns of adfluvial and reservoir fish in Box Canyon Reservoir and its tributaries, a baseline assessment of Boundary Reservoir and its tributaries, ecological assessment of mountain lakes in Pend Oreille County, and assessments of streams and lakes on the Spokane Indian Reservation were completed by 2001. Assessments of the Little Spokane River and its tributaries, tributaries to the Pend Oreille River, small lakes in Pend Oreille County, WA, and water bodies within and near the Spokane Indian Reservation were conducted in 2002. This work was done in accordance with the scope of work approved by Bonneville Power Administration (BPA).

Connor, Jason M. (Kalispel Department of Natural Resources, Usk, WA); McLellan, Jason G. (Washington Department of Fish and Wildlife, Spokane, WA); Butler, Chris (Spokane Tribe of Indians, Department of Natural Resources, Wellpinit, WA)

2003-09-01

33

Resident Fish Stock Status above Chief Joseph and Grand Coulee Dams; 2001 Annual Report.  

Energy Technology Data Exchange (ETDEWEB)

In 1980, the United States Congress enacted the Northwest Power Planning and Conservation Act (PL 96-501, 1980), which established the Northwest Power Planning Council (NPPC). The NPPC was directed by Congress to develop a regional Power Plan and also the Columbia River Basin Fish and Wildlife Program (FWP) to restore or replace losses of fish caused by construction and operation of hydroelectric dams in the Columbia River Basin. In developing the FWP, Congress specifically directed NPPC to solicit recommendations for measures to be included in the Program from the region's fish and wildlife agencies and Indian tribes. All measures adopted by the Council were also required to be consistent with the management objectives of the agencies and tribes [Section 4.(h)(6)(A)], the legal rights of Indian tribes in the region [Section 4.(h)(6)(D)] and be based upon and supported by the best available scientific knowledge [Section 4.(h)(6)(B)]. The Resident Fish Stock Status above Chief Joseph and Grand Coulee Dams Project, also known as the Joint Stock Assessment Project (JSAP) specifically addresses NPPC Council measure 10.8B.26 of the 1994 program. The Joint Stock Assessment Project is a management tool using ecosystem principles to manage artificial fish assemblages and native fish in altered environments existing in the Columbia River System above Chief Joseph and Grand Coulee Dams (Blocked Area). A three-phase approach of this project will enhance the fisheries resources of the Blocked Area by identifying data gaps, filling data gaps with research, and implementing management recommendations based on research results. The Blocked Area fisheries information is housed in a central location, allowing managers to view the entire system while making decisions, rather than basing management decisions on isolated portions of the system. The JSAP is designed and guided jointly by fisheries managers in the Blocked Area and the Columbia Basin Blocked Area Management Plan (1998). The initial year of the project (1997) identified the need for a central data storage and analysis facility, coordination with the StreamNet project, compilation of Blocked Area fisheries information, and a report on the ecological condition of the Spokane River System. These needs were addressed in 1998 by acquiring a central location with a data storage and analysis system, coordinating a pilot project with StreamNet, compiling fisheries distribution data throughout the Blocked Area, identifying data gaps based on compiled information, and researching the ecological condition of the Spokane River. In order to ensure that any additional information collected throughout the life of this project will be easily stored and manipulated by the central storage facility, it was necessary to develop standardized methodologies between the JSAP fisheries managers. Common collection and analytical methodologies were developed in 1999. In 1999, 2000, and 2001 the project began addressing some of the identified data gaps throughout the Blocked Area. Data collection of established projects and a variety of newly developed sampling projects are ongoing. Projects developed and undertaken by JSAP fisheries managers include investigations of the Pend Orielle River and its tributaries, the Little Spokane River and its tributaries, and water bodies within and near the Spokane Indian Reservation. Migration patterns of adfluvial and reservoir fish in Box Canyon Reservoir and its tributaries, a baseline assessment of Boundary Reservoir and its tributaries, ecological assessment of mountain lakes in Pend Oreille County, and assessments of seven streams and four lakes on the Spokane Indian Reservation were completed by 2000. Assessments of the Little Spokane River and its tributaries, tributaries to the Pend Oreille River, small lakes in southern Pend Oreille County, and water bodies within and near the Spokane Indian Reservation were conducted in 2001. This work was done in accordance with the scope of work approved by Bonneville Power Administration (BPA).

Connor, Jason M. (Kalispell Department of Natural Resources, Usk, WA); McLellan, Jason G. (Washington Department of Fish and Wildlife, Spokane, WA); O' Connor, Dick (Washington Department of Fish and Wildlife, Olympia, WA)

2003-01-01

34

Resident Fish Stock Status above Chief Joseph and Grand Coulee Dams; 2002-2003 Annual Report.  

Energy Technology Data Exchange (ETDEWEB)

In 1980, the United States Congress enacted the Northwest Power Planning and Conservation Act (PL 96-501, 1980), which established the Northwest Power and Conservation Council (NPCC), formerly the Northwest Power Planning Council. The NPCC was directed by Congress to develop a regional Power Plan and also the Columbia River Basin Fish and Wildlife Program (FWP) to restore or replace losses of fish caused by construction and operation of hydroelectric dams in the Columbia River Basin. In developing the FWP, Congress specifically directed NPCC to solicit recommendations for measures to be included in the Program from the region's fish and wildlife agencies and Indian tribes. All measures adopted by the Council were also required to be consistent with the management objectives of the agencies and tribes [Section 4.(h)(6)(A)], the legal rights of Indian tribes in the region [Section 4.(h)(6)(D)] and be based upon and supported by the best available scientific knowledge [Section 4.(h)(6)(B)]. The Resident Fish Stock Status above Chief Joseph and Grand Coulee Dams Project, also known as the Joint Stock Assessment Project (JSAP) specifically addresses NPPC Council measure 10.8B.26 of the 1994 program. The Joint Stock Assessment Project is a management tool using ecosystem principles to manage artificial and native fish assemblages in altered environments existing in the Columbia River System above Chief Joseph and Grand Coulee Dams (Blocked Area). A three-phase approach of this project will enhance the fisheries resources of the Blocked Area by identifying data gaps, filling data gaps with research, and implementing management recommendations based on research results. The Blocked Area fisheries information is housed in a central location, allowing managers to view the entire system while making decisions, rather than basing management decisions on isolated portions of the system. The JSAP is designed and guided jointly by fisheries managers in the Blocked Area. The initial year of the project (1997) identified the need for a central data storage and analysis facility, coordination with the StreamNet project, compilation of Blocked Area fisheries information, and a report on the ecological condition of the Spokane River System. These needs were addressed in 1998 by acquiring a central location with a data storage and analysis system, coordinating a pilot project with StreamNet, compiling fisheries distribution data throughout the Blocked Area, identifying data gaps based on compiled information, and researching the ecological condition of the Spokane River. In order to ensure that any additional information collected throughout the life of this project will be easily stored and manipulated by the central storage facility, it was necessary to develop standardized methodologies between the JSAP fisheries managers. Common collection and analytical methodologies were developed in 1999. The project began addressing identified data gaps throughout the Blocked Area in 1999. Data collection of established projects and a variety of newly developed sampling projects are ongoing. Projects developed and undertaken by JSAP fisheries managers include investigations of the Pend Orielle River and its tributaries, the Little Spokane River and its tributaries, and water bodies within and near the Spokane Indian Reservation. Migration patterns of adfluvial and reservoir fish in Box Canyon Reservoir and its tributaries, a baseline assessment of Boundary Reservoir and its tributaries, ecological assessment of mountain lakes in Pend Oreille County, and assessments of streams and lakes on the Spokane Indian Reservation were completed by 2001. Assessments of the Little Spokane River and its tributaries, Spokane River below Spokane Falls, tributaries to the Pend Oreille River, small lakes in Pend Oreille County, WA, and water bodies within and near the Spokane Indian Reservation were conducted in 2002 and 2003. This work was done in accordance with the scope of work approved by Bonneville Power Administration (BPA).

Connor, Jason M. (Kalispel Tribe of Indians, Usk, WA); McLellan, Jason G. (Washington Department of Fish and Wildlife); Butler, Chris (Spokane Tribe of Indians, Wellpinit, WA)

2006-02-01

35

Resident Fish Stock above Chief Joseph and Grand Coulee Dams; 2003-2004 Annual Report.  

Energy Technology Data Exchange (ETDEWEB)

In 1980, the United States Congress enacted the Northwest Power Planning and Conservation Act (PL 96-501, 1980), which established the Northwest Power and Conservation Council (NPCC), formerly the Northwest Power Planning Council. The NPCC was directed by Congress to develop a regional Power Plan and also the Columbia River Basin Fish and Wildlife Program (FWP) to restore or replace losses of fish caused by construction and operation of hydroelectric dams in the Columbia River Basin. In developing the FWP, Congress specifically directed NPCC to solicit recommendations for measures to be included in the Program from the region's fish and wildlife agencies and Indian tribes. All measures adopted by the Council were also required to be consistent with the management objectives of the agencies and tribes [Section 4.(h)(6)(A)], the legal rights of Indian tribes in the region [Section 4.(h)(6)(D)] and be based upon and supported by the best available scientific knowledge [Section 4.(h)(6)(B)]. The Resident Fish Stock Status above Chief Joseph and Grand Coulee Dams Project, also known as the Joint Stock Assessment Project (JSAP) specifically addresses NPPC Council measure 10.8B.26 of the 1994 program. The Joint Stock Assessment Project is a management tool using ecosystem principles to manage artificial and native fish assemblages in altered environments existing in the Columbia River System above Chief Joseph and Grand Coulee Dams (Blocked Area). A three-phase approach of this project will enhance the fisheries resources of the Blocked Area by identifying data gaps, filling data gaps with research, and implementing management recommendations based on research results. The Blocked Area fisheries information is housed in a central location, allowing managers to view the entire system while making decisions, rather than basing management decisions on isolated portions of the system. The JSAP is designed and guided jointly by fisheries managers in the Blocked Area. The initial year of the project (1997) identified the need for a central data storage and analysis facility, coordination with the StreamNet project, compilation of Blocked Area fisheries information, and a report on the ecological condition of the Spokane River System. These needs were addressed in 1998 by acquiring a central location with a data storage and analysis system, coordinating a pilot project with StreamNet, compiling fisheries distribution data throughout the Blocked Area, identifying data gaps based on compiled information, and researching the ecological condition of the Spokane River. In order to ensure that any additional information collected throughout the life of this project will be easily stored and manipulated by the central storage facility, it was necessary to develop standardized methodologies between the JSAP fisheries managers. Common collection and analytical methodologies were developed in 1999. The project began addressing identified data gaps throughout the Blocked Area in 1999. Data collection of established projects and a variety of newly developed sampling projects are ongoing. Projects developed and undertaken by JSAP fisheries managers include investigations of the Pend Orielle River and its tributaries, the Little Spokane River and its tributaries, and water bodies within and near the Spokane Indian Reservation. Migration patterns of adfluvial and reservoir fish in Box Canyon Reservoir and its tributaries, a baseline assessment of Boundary Reservoir and its tributaries, ecological assessment of mountain lakes in Pend Oreille County, and assessments of streams and lakes on the Spokane Indian Reservation were completed by 2001. Assessments of the Little Spokane River and its tributaries, Spokane River below Spokane Falls, tributaries to the Pend Oreille River, small lakes in Pend Oreille County, WA, and water bodies within and near the Spokane Indian Reservation were conducted in 2002 and 2003. This work was done in accordance with the scope of work approved by Bonneville Power Administration (BPA).

Connor, Jason M. (Kalispel Tribe of Indians, Usk, WA); McLellan, Jason G. (Washington Department of Fish and Wildlife, Olympia, WA); Butler, Chris (Spokane Tribe of Indians, Wellpinit, WA)

2005-11-01

36

Changes in the fish community and water quality during seven years of stocking piscivorous fish in a shallow lake  

DEFF Research Database (Denmark)

1. Piscivores (annual stocking of 1000 individuals ha(-1) of 0+ pike and a single stocking of 30 kg ha(-1) of large 20-30 cm perch) were stocked in seven consecutive years in a shallow eutrophic lake in Denmark. The stocking programme aimed at changing food-web structure by reducing zooplanktivorous and benthivorous fish, with resultant effects on lower trophic levels and ultimately water quality. 2. The fish community and water quality parameters (Secchi depth, concentrations of total phosphorus, chlorophyll a and suspended solids) were monitored between 1996 and 2000 and relationships were evaluated between predatory fish and potential prey and between zooplanktivorous or benthivorous fish and water quality parameters. In addition, potential consumption of piscivorous fishes was calculated. 3. The density of fish feeding on larger zooplankton or benthos (roach >15 cm, crucian carp >15 cm) declined distinctly during the study period. This effect was attributed to predation by large (>50 cm) pike. Based on scale readings, we cautiously suggest that the stocking of 0+ pike boosted the adult pike population to produce an unexpected impact in later years. Conversely, no direct impact of stocked 0+ pike was detected on 0+ roach. 4. A major decline in the recruitment strength of 0+ roach was observed in 2000. A combination of (i) the indirect effect of large pike preying on adult roach, with negative effect on roach reproduction and (ii) the direct predation effect of 0+ pike and or 1+ and 2+ perch recruited in the lake, provides the most likely explanation of this phenomenon. 5. A marked increase in Secchi depth in 2000 and declining trends in suspended solids, chlorophyll-a and total phosphorus concentrations were observed. These changes may also be attributable to changes in the fish community, although the relationships were not straightforward. 6. This 7-year study indicates that piscivorous fish may be a significant structuring force in shallow eutrophic lakes, suggesting that stocking piscivores can increase predation pressure on cyprinids. However, the general lack of impact of 0+ pike points to the need of refining current stocking practices in several countries across Europe

Skov, Christian; Perrow, M.R.

2002-01-01

37

Annual Stock Assessment - CWT [Coded Wire Tag program] (USFWS), Annual Report 2007.  

Energy Technology Data Exchange (ETDEWEB)

In 1989 the Bonneville Power Administration (BPA) began funding the evaluation of production groups of juvenile anadromous fish not being coded-wire tagged for other programs. These groups were the 'Missing Production Groups'. Production fish released by the U.S. Fish and Wildlife Service (FWS) without representative coded-wire tags during the 1980s are indicated as blank spaces on the survival graphs in this report. This program is now referred to as 'Annual Stock Assessment - CWT'. The objectives of the 'Annual Stock Assessment' program are to: (1) estimate the total survival of each production group, (2) estimate the contribution of each production group to fisheries, and (3) prepare an annual report for USFWS hatcheries in the Columbia River basin. Coded-wire tag recovery information will be used to evaluate the relative success of individual brood stocks. This information can also be used by salmon harvest managers to develop plans to allow the harvest of excess hatchery fish while protecting threatened, endangered, or other stocks of concern. All fish release information, including marked/unmarked ratios, is reported to the Pacific States Marine Fisheries Commission (PSMFC). Fish recovered in the various fisheries or at the hatcheries are sampled to recover coded-wire tags. This recovery information is also reported to PSMFC. This report has been prepared annually starting with the report labeled 'Annual Report 1994'. Although the current report has the title 'Annual Report 2007', it was written in fall of 2008 using data available from RMIS that same year, and submitted as final in January 2009. The main objective of the report is to evaluate survival of groups which have been tagged under this ongoing project.

Pastor, Stephen M. [U.S. Fish and Wildlife Service, Columbia River Fisheries Program Office

2009-07-21

38

Forecasting Fish Stock Recruitment and Planning Optimal Harvesting Strategies by Using Neural Network  

Directory of Open Access Journals (Sweden)

Full Text Available Recruitment prediction is a key element for management decisions in many fisheries. A new approach using neural network is developed as a tool to produce a formula for forecasting fish stock recruitment. In order to deal with the local minimum problem in training neural network with back-propagation algorithm and to enhance forecasting precision, neural network’s weights are adjusted by optimization algorithm. It is demonstrated that a well trained artificial neural network reveals an extremely fast convergence and a high degree of accuracy in the prediction of fish stock recruitment.

Lin Sun; Hongjun Xiao; Shouju Li; Dequan Yang

2009-01-01

39

Resident Fish Stock Status above Chief Joseph and Grand Coulee Dams; 2000 Annual Report.  

Energy Technology Data Exchange (ETDEWEB)

The Resident Fish Stock Status above Chief Joseph and Grand Coulee Dams Project, commonly known as the Joint Stock Assessment Project (JSAP) is a management tool using ecosystem principles to manage artificial fish assemblages and native fish in altered environments existing in the Columbia River System above Chief Joseph and Grand Coulee Dams (blocked area). The three-phase approach of this project will enhance the fisheries resources of the blocked area by identifying data gaps, filling data gaps with research, and implementing management recommendations based on research results. The Blocked Area fisheries information housed in a central location will allow managers to view the entire system while making decisions, rather than basing management decisions on isolated portions of the system. The JSAP (NWPPC program measure 10.8B.26) is designed and guided jointly by fisheries managers in the blocked area and the Columbia Basin blocked area management plan (1998). The initial year of the project (1997) identified the need for a central data storage and analysis facility, coordination with the StreamNet project, compilation of blocked area fisheries information, and a report on the ecological condition of the Spokane River System. These needs were addressed in 1998 by acquiring a central location with a data storage and analysis system, coordinating a pilot project with StreamNet, compiling fisheries distribution data throughout the blocked area, identifying data gaps based on compiled information, and researching the ecological condition of the Spokane River. In order to ensure that any additional information collected throughout the life of this project will be easily stored and manipulated by the central storage facility, it was necessary to develop standardized methodologies between the JSAP fisheries managers. The use of common collection and analytical tools is essential to the process of streamlining joint management decisions. In 1999 and 2000 the project began to address some of the identified data gaps, throughout the blocked area, with a variety of newly developed sampling projects, as well as, continuing with ongoing data collection of established projects.

Crossley, Brian (Spokane Tribe of Indians, Department of Natural Resources, Wellpinit, WA); Lockwood, Jr., Neil W. (Kalispel Tribe of Indians, Usk, WA); McLellan, Jason G. (Washington Department of Fish and Wildlife, Spokane, WA)

2001-01-01

40

Duck Valley Reservoirs Fish Stocking and Operation and Maintenance, 2006-2007 Annual Progress Report.  

Energy Technology Data Exchange (ETDEWEB)

The Duck Valley Reservoirs Fish Stocking and Operations and Maintenance (DV Fisheries) project is an ongoing resident fish program that serves to partially mitigate the loss of anadromous fish that resulted from downstream construction of the hydropower system. The project's goals are to enhance subsistence fishing and educational opportunities for Tribal members of the Shoshone-Paiute Tribes and provide resident fishing opportunities for non-Tribal members. In addition to stocking rainbow trout (Oncorhynchus mykiss) in Mountain View, Lake Billy Shaw, and Sheep Creek Reservoirs, the program is also designed to maintain healthy aquatic conditions for fish growth and survival, to provide superior facilities with wilderness qualities to attract non-Tribal angler use, and to offer clear, consistent communication with the Tribal community about this project as well as outreach and education within the region and the local community. Tasks for this performance period are divided into operations and maintenance plus monitoring and evaluation. Operation and maintenance of the three reservoirs include fences, roads, dams and all reservoir structures, feeder canals, water troughs and stock ponds, educational signs, vehicles and equipment, and outhouses. Monitoring and evaluation activities included creel, gillnet, wildlife, and bird surveys, water quality and reservoir structures monitoring, native vegetation planting, photo point documentation, control of encroaching exotic vegetation, and community outreach and education. The three reservoirs are monitored in terms of water quality and fishery success. Sheep Creek Reservoir was very unproductive this year as a fishery. Fish morphometric and water quality data indicate that the turbidity is severely impacting trout survival. Lake Billy Shaw was very productive as a fishery and received good ratings from anglers. Mountain View was also productive and anglers reported a high number of quality sized fish. Water quality (specifically dissolved oxygen and temperature) is the main limiting factor in our fisheries.

Sellman, Jake; Dykstra, Tim [Shoshone-Paiute Tribes

2009-05-11

 
 
 
 
41

Effects of acid rock drainage on stocked rainbow trout (Oncorhynchus mykiss): an in-situ, caged fish experiment.  

UK PubMed Central (United Kingdom)

In-situ caged rainbow trout (Oncorhynchus mykiss) studies reveal significant fish toxicity and fish stress in a river impacted by headwater acid rock drainage (ARD). Stocked trout survival and aqueous water chemistry were monitored for 10 days at 3 study sites in the Snake River watershed, Colorado, U.S.A. Trout mortality was positively correlated with concentrations of metals calculated to be approaching or exceeding conservative toxicity thresholds (Zn, Mn, Cu, Cd). Significant metal accumulation on the gills of fish stocked at ARD impacted study sites support an association between elevated metals and fish mortality. Observations of feeding behavior and significant differences in fish relative weights between study site and feeding treatment indicate feeding and metals-related fish stress. Together, these results demonstrate the utility of in-situ exposure studies for stream stakeholders in quantifying the relative role of aqueous contaminant exposures in limiting stocked fish survival.

Todd AS; McKnight DM; Jaros CL; Marchitto TM

2007-07-01

42

Climate, competition and the management of shared fish stocks  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Long-term climate regime shifts have profound impacts on ocean temperature and circulation patterns, and on the dynamics of fish populations. Climate regime shifts can disrupt otherwise satisfactory international management agreements. Game theory provides a perspective on the difficulty of maintain...

Miller, Kathleen; Munro, Gordon R.; Bjørndal, Trond

43

State of marine fish stock in the Caspian Sea (from results of the research in 2011)  

Directory of Open Access Journals (Sweden)

Full Text Available The paper analyzes the state of the main commercially valuable marine fish stock in the Caspian Sea. It was established that the present-day kilka fishery harvested the minimal amount of anchovy and big-eyed kilka. Their abundance has decreased drastically, natural spawning has declined, commercial stock becomes depleted rapidly. Annually common kilka reproduction remains at an average long-term level. The stock of marine shad is quite stable with the most abundant Dolginka shad. Population replenishment depends on the abundance of food organisms and water temperature in the northern part of the Caspian Sea. The silverside is taken as a by-catch when common kilka are harvested. Its stock is stable. It is recommended that the species harvest should be increased. Only one mullet species (golden gray mullet) may be seen in catch. Its stock is quite stable while commercial catches depend on fishery management. Marine fish resources (except for anchovy and big-eyed kilka) make it possible to increase their commercial exploitation.

Khodorevskaya Raisa Pavlovna; Asejnova Aliya Akhmetovna; Parickiy Yuriy Aleksandrovich; Kanatyev Sergey Vladimirovich; Gavrilova Darya Aleksandrovna; Zubkova Tatyana Stanislavona; Abdulaeva Dina Rashitovna

2013-01-01

44

Fish Catch Assessment of Maljhee-Kangsa Floodplain in Bangladesh  

Directory of Open Access Journals (Sweden)

Full Text Available A study was conducted to assess fish catch in the Baila beel of Maljhee-Kangsa floodplain in the north-central part of Bangladesh. A total of 7 types of fishing gear were found in use by the fishermen which are: push net, gill net, cast net, lift net, current net, fish traps and hooks. The duration of fishing depends on use of fishing gear, season, habitat type, water depth and abundance of fishes. From the survey it was found that the highest average fishing time was estimated in fish trap (18.04 h/day) and the lowest in push net (3.21 h/day). There are variations in the Catch Per Unit of Effort (CPUE) of different gears in different seasons. The highest and the lowest CPUE were recorded in current net and hook which were 0.31 and 0.02 kg/gear/h, respectively. According to the fishermen, the highest catch was obtained during the receding of floodwater in post-monsoon season (October-December) and the lowest during the pre-monsoon season (April-June). A total of 39 fish species were identified in the catches of different gears. From the survey it was found that a fisherman daily catches an average 1.43 kg of fish. Alarmingly, the catch of fish has declined by an estimated 20% in the past five years. Concerns arise about the sustainable catches due to over fishing and indiscriminate use of gears. It is therefore necessary to provide institutional and organisational supports for artificial stocking and establishing fish sanctuaries through active community participation for sustainable catches.

N. Ahmed; M.M. Rahman; M.M. Rahman

2005-01-01

45

Admixture analysis and stocking impact assessment in brown trout ( Salmo trutta ), estimated with incomplete baseline data  

DEFF Research Database (Denmark)

Studies of genetic interactions between wild and domesticated fish are often hampered by unavailability of samples from wild populations prior to population admixture. We assessed the utility of a new Bayesian method, which can estimate individual admixture coefficients even with data missing from the populations contributing to admixture. We applied the method to analyse the genetic contribution of domesticated brown trout (Salmo trutta) in samples of anadromous trout from two stocked populations with no genetic data available before stocking. Further, we estimated population level admixture proportions by the mean of individual admixture coefficients. This method proved more informative than a multidimensional scaling analysis of individual-based genetic distances and assignment tests. The results showed almost complete absence of stocked, domesticated trout in samples of trout from the rivers. Consequently, stocking had little effect on improving fisheries. In one population, the genetic contribution by domesticated trout was small, whereas in the other population, some genetic impact was suggested. Admixture in this sample of anadromous trout despite absence of stocked domesticated trout could be because of introgression by domesticated trout adopting a resident life history.

Hansen, Michael MØller; Eg Nielsen, Einar

2001-01-01

46

An Individual-based Probabilistic Model for Fish Stock Simulation  

CERN Multimedia

We define an individual-based probabilistic model of a sole (Solea solea) behaviour. The individual model is given in terms of an Extended Probabilistic Discrete Timed Automaton (EPDTA), a new formalism that is introduced in the paper and that is shown to be interpretable as a Markov decision process. A given EPDTA model can be probabilistically model-checked by giving a suitable translation into syntax accepted by existing model-checkers. In order to simulate the dynamics of a given population of soles in different environmental scenarios, an agent-based simulation environment is defined in which each agent implements the behaviour of the given EPDTA model. By varying the probabilities and the characteristic functions embedded in the EPDTA model it is possible to represent different scenarios and to tune the model itself by comparing the results of the simulations with real data about the sole stock in the North Adriatic sea, available from the recent project SoleMon. The simulator is presented and made avai...

Buti, Federico; Merelli, Emanuela; Paschini, Elio; Penna, Pierluigi; Tesei, Luca; 10.4204/EPTCS.33.3

2010-01-01

47

Risk assessment in airlines stocks market  

Directory of Open Access Journals (Sweden)

Full Text Available In this paper we compared the results between stock portfolios of North American and European airlines. The model accesses the market risk using Value-at-Risk approach in both portfolios over one month period. The analysis was performed through the use of GARCH-EVT methods and Student’s-t Copula with a Monte Carlo Simulation. The assets in the financial market usually present heavy tails in their probability distributions, so, a process capable to deal with this issue is crucial to measure the risk of loss. We analyzed the period from mid-2007 to mid-2012 to compose comparison between these two portfolios. The financial crisis of 2008 had a great impact in the North America market in relative to the European market. The central role of transport in the economy makes studies dealing with investment risk measure in this sector crucial for the industrial development. The volatility of risk in the airline market happens by internal and external motives and the methodological development of financial tools can offer an important contribution due the investment flux dependency.

Renato Cesar Sato

2013-01-01

48

Duck Valley Reservoirs Fish Stocking and O&M, Annual Progress Report 2007-2008.  

Energy Technology Data Exchange (ETDEWEB)

The Duck Valley Reservoirs Fish Stocking and Operations and Maintenance Project (DV Fisheries) is an ongoing resident fish program that serves to partially mitigate the loss of anadromous fish that resulted from downstream construction of the federal hydropower system. The project's goals are to enhance subsistence fishing and educational opportunities for Tribal members of the Shoshone-Paiute Tribes and provide fishing opportunities for non-Tribal members. In addition to stocking rainbow trout (Oncorhynchus mykiss) in Mountain View (MVR), Lake Billy Shaw (LBS), and Sheep Creek Reservoirs (SCR), the program is also designed to: maintain healthy aquatic conditions for fish growth and survival, provide superior facilities with wilderness qualities to attract non-Tribal angler use, and offer clear, consistent communication with the Tribal community about this project as well as outreach and education within the region and the local community. Tasks for this performance period fall into three categories: operations and maintenance, monitoring and evaluation, and public outreach. Operation and maintenance of the three reservoirs include maintaining fences, roads, dams and all reservoir structures, feeder canals, water troughs, stock ponds, educational signs, vehicles, equipment, and restroom facilities. Monitoring and evaluation activities include creel, gillnet, wildlife, and bird surveys, water quality and reservoir structures monitoring, native vegetation planting, photo point documentation, and control of encroaching exotic vegetation. Public outreach activities include providing environmental education to school children, providing fishing reports to local newspapers and vendors, updating the website, hosting community environmental events, and fielding numerous phone calls from anglers. The reservoir monitoring program focuses on water quality and fishery success. Sheep Creek Reservoir and Lake Billy Shaw had less than productive trout growth due to water quality issues including dissolved oxygen and/or turbidity. Regardless, angler fishing experience was the highest at Lake Billy Shaw. Trout in Mountain View Reservoir were in the best condition of the three reservoirs and anglers reported very good fishing there. Water quality (specifically dissolved oxygen and temperature) remain the main limiting factors in the fisheries, particularly in late August to early September.

Sellman, Jake; Perugini, Carol [Department of Fish, Wildlife, and Parks, Shoshone-Paiute Tribes

2009-02-20

49

SPAM (Sex-Structured Pandalus Assessment Model): a stock assessment model for Pandalus stocks  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Malgré l’importance économique des pêches aux crevettes Pandalus, peu d’outils ont été mis au point pour en évaluer les stocks, car les modèles d’évaluation courants ne sont pas appropriés à cause des caractéristiques biologiques particulières des espèces de Pandalus. Dans ce contexte, nous proposon...

Drouineau, H.; Savard, L.; Desgagnés, M.; Duplisea, D.

50

Annual Coded Wire Tag Program; Oregon Stock Assessment, 2000 Annual Report.  

Energy Technology Data Exchange (ETDEWEB)

This annual report is in fulfillment of contract obligations with Bonneville Power Administration which is the funding source for the Oregon Department of Fish and Wildlife's Annual Stock Assessment - Coded Wire Tag Program (ODFW) Project. Tule stock fall chinook were caught primarily in British Columbia and Washington ocean, and Columbia Basin fisheries. Up-river bright stock fall chinook contributed primarily to Alaska and British Columbia ocean commercial, Columbia Basin gillnet and freshwater sport fisheries. Contribution of Rogue stock fall chinook released in the lower Columbia River occurred primarily in Oregon ocean commercial, Columbia Basin gillnet and freshwater sport fisheries. Willamette stock spring chinook contributed primarily to Alaska and British Columbia ocean, and Columbia Basin sport fisheries. Willamette stock spring chinook released by CEDC contributed to similar ocean fisheries, but had much higher catch in Columbia Basin gillnet fisheries than the same stocks released in the Willamette Basin. Up-river stocks of spring chinook contributed almost exclusively to Columbia Basin fisheries. The up-river stocks of Columbia River summer steelhead contributed almost exclusively to the Columbia Basin gillnet and freshwater sport fisheries. Coho ocean fisheries from Washington to California were closed or very limited from 1994 through 1999 (1991 through 1996 broods). This has resulted in a lower percent of catch in Washington, Oregon and California ocean fisheries, and a higher percent of catch in Alaska and British Columbia ocean and Columbia Basin freshwater fisheries. Coho stocks released by ODFW below Bonneville Dam were caught mainly in Oregon, Washington, and British Columbia ocean, Columbia Gillnet and freshwater sport fisheries. Coho stocks released in the Klaskanine River and Youngs Bay area had similar ocean catch distributions, but a much higher percent catch in gillnet fisheries than the other coho releases. Ocean catch distribution of coho stocks released above Bonneville Dam was similar to the other coho groups. However, they had a higher percent catch in gillnet fisheries above Bonneville Dam than coho released below the dam. Survival rates of salmon and steelhead are influenced, not only by factors in the hatchery (disease, density, diet, size and time of release) but also by environmental factors in the river and ocean. These environmental factors are influenced by large scale oceanic and weather patterns such as El Nino. Changes in rearing conditions in the hatchery do impact survival, however, these can be offset by impacts caused by environmental factors. Coho salmon released in the Columbia River generally experience better survival rates when released later in the spring. However, for the 1990 brood year June releases of Columbia River coho had much lower survival than May releases, for all ODFW hatcheries. In general survival of ODFW Columbia River hatchery coho has declined to low levels in recent years. Preliminary results from the evaluation of Visual Implant Elastomer (VIE) tags showed tagging rate and pre-release tag retention improved from the first to second years of tagging. Tagging rate remained identical from 1999 to 2000 while pre-release tag retention dropped to 95%. Returning jack and adult salmon were sampled for CWT and VIE tags in the fall of 2000. Of 606 adults recovered at Sandy Fish Hatchery in 2000, only 1 or 0.2%, retained their VIE tag. Of 36 jacks recovered in 2000, 13 or 36.1% retained their VIE tag.

Lewis, Mark; Mallette, Christine; Murray, William

2002-03-01

51

Micro-PIXE analysis of fish otoliths. Methodology and evaluation of first results for stock discrimination  

Energy Technology Data Exchange (ETDEWEB)

Micro-PIXE has been used to measure the trace element distribution in otoliths from several species of ocean fish, in order to investigate its possible use in stock discrimination. Trace elements detected include Sr, Fe, Mn, Ni, Zn, Cu, Se, Cd, Br, Hg and Pb. Trace elements Na, K, Cl, S and Cl were detected with the electron microprobe. The high sensitivity of PIXE demands a meticulous sample preparation procedure to avoid contamination problems. Practical problems associated with the application of the technique were investigated in detail. Preliminary results indicate that most trace elements except Sr, are present at close to the limits of detection at few ppm, but biologically significant data can be obtained for stock discrimination applications. (author).

Sie, S.H. [Commonwealth Scientific and Industrial Research Organization, North Ryde, NSW (Australia). Div. of Exploration Geoscience; Thresher, R.E.

1992-12-31

52

Micro-PIXE analysis of fish otoliths. Methodology and evaluation of first results for stock discrimination  

International Nuclear Information System (INIS)

Micro-PIXE has been used to measure the trace element distribution in otoliths from several species of ocean fish, in order to investigate its possible use in stock discrimination. Trace elements detected include Sr, Fe, Mn, Ni, Zn, Cu, Se, Cd, Br, Hg and Pb. Trace elements Na, K, Cl, S and Cl were detected with the electron microprobe. The high sensitivity of PIXE demands a meticulous sample preparation procedure to avoid contamination problems. Practical problems associated with the application of the technique were investigated in detail. Preliminary results indicate that most trace elements except Sr, are present at close to the limits of detection at few ppm, but biologically significant data can be obtained for stock discrimination applications. (author).

1992-01-01

53

Assessing changes in amphibian population dynamics following experimental manipulations of introduced fish.  

UK PubMed Central (United Kingdom)

Sport-fish introductions are now recognized as an important cause of amphibian decline, but few researchers have quantified the demographic responses of amphibians to current options in fisheries management designed to minimize effects on sensitive amphibians. Demographic analyses with mark-recapture data allow researchers to assess the relative importance of survival, local recruitment, and migration to changes in population densities. I conducted a 4-year, replicated whole-lake experiment in the Klamath Mountains of northern California (U.S.A.) to quantify changes in population density, survival, population growth rate, and recruitment of the Cascades frog (Rana cascadae) in response to manipulations of non-native fish populations. I compared responses of the frogs in lakes where fish were removed, in lakes in their naturally fish-free state, and in lakes where fish remained that were either stocked annually or no longer being stocked. Within 3 years of fish removals from 3 lakes, frog densities increased by a factor of 13.6. The survival of young adult frogs increased from 59% to 94%, and realized population growth and recruitment rates at the fish-removal lakes were more than twice as high as the rates for fish-free reference lakes and lakes that contained fish. Population growth in the fish-removal lakes was likely due to better on-site recruitment of frogs to later life stages rather than increased immigration. The effects on R. cascadae of suspending stocking were ambiguous and suggested no direct benefit to amphibians. With amphibians declining worldwide, these results show that active restoration can slow or reverse the decline of species affected by fish stocking within a short time frame.

Pope KL

2008-12-01

54

Growth and production performance of threatened snakehead fish, Channa striatus (Bloch), at different stocking densities in earthen ponds  

UK PubMed Central (United Kingdom)

Production trials of threatened snakehead fish (Channa striatus) were carried out under different stocking densities in earthen ponds of Bangladesh. The average weight and length of the fingerlings during stocking was 17.63 ± 1.23?g and 13.21 ± 0.52?cm. Fingerlings were stocked at 5000?ha?1 in treatment?1 (T1), 6250?ha?1 in treatment?2 (T2) and 7500?ha?1 in treatment?3 (T3) respectively. Fish in all the experimental ponds were fed with supplementary feed comprising of fish meal (30%) and mustard oilcake (70%) at the rate of 3–6% of estimated body weight two times per day. In addition, trash fish were supplied at the rate of 2–3% of the estimated biomass on each alternate day. In situ water quality parameters of the pond were within the suitable range for fish culture. The growth and survival of fingerlings were significantly higher in T1 than in T2 and T3. The food conversion ratio was significantly lower (P<0.05) in T1 than in T2 and T3. The estimated gross and net production of fish was higher in T1, followed by T2 and T3. Overall, the highest growth, survival and production were obtained from T1. Therefore, it could be concluded that of 5000?fingerlings?ha?1 is the most suitable stocking density for culturing C. striatus under a monoculture system in the earthen ponds for better production.

Aminur Rahman M; Arshad A; Nurul Amin SM

2012-01-01

55

Stocking of Offsite Waters for Hungry Horse Dam Mitigation; Creston National Fish Hatchery, 2001-2002 Annual Report.  

Energy Technology Data Exchange (ETDEWEB)

Mitigation Objective 1: Produce Native Westslope Cutthroat Trout at Creston NFH--Task: Acquire eggs and rear up to 100,000 Westslope Cutthroat trout annually for offsite mitigation stocking. Accomplishments: A total of 150,000 westslope cutthroat eggs (M012 strain) were acquired from the State of Montana Washoe Park State Fish Hatchery in July 2001 for this objective. Another 120,000 westslope cutthroat eggs were taken from feral fish at Rogers Lake in May of 2001 by the Creston Hatchery crew. The fish were reared using approved fish culture techniques as defined in the U.S. Department of the Interior Fish Hatchery Management guidelines. Post release survival and angler success is monitored annually by Montana Fish Wildlife and Parks (MFWP) and the Confederated Salish and Kootenai Tribe (CSKT). Stocking numbers and locations may vary yearly based on results of biological monitoring. Mitigation Objective 2: Produce Rainbow Trout at Creston NFH--Task: Acquire and rear up to 100,000 Rainbow trout annually for offsite mitigation in closed basin waters. Accomplishments: A total of 50,500 rainbow trout eggs (Arlee strain) were acquired from the State of Montana Arlee State Fish Hatchery in December 2001 for this objective. The fish were reared using approved fish culture techniques as defined in the U.S. Department of the Interior Fish Hatchery Management guidelines. Arlee rainbow trout are being used for this objective because the stocking locations are terminal basin reservoirs and habitat conditions and returns to creel are unsuitable for native cutthroat. Post release survival and angler success is monitored annually by the Confederated Salish and Kootenai Tribe (CSKT). Stocking numbers and locations may vary yearly based on results of biological monitoring.

Maskill, Mark (US Fish and Wildlife Service, Creston National Fish Hatchery, Kalispell, MT)

2003-03-01

56

Stocking of Offsite Waters for Hungry Horse Dam Mitigation; Creston National Fish Hatchery, 2002-2003 Annual Report.  

Energy Technology Data Exchange (ETDEWEB)

Mitigation Objective 1: Produce Native Westslope Cutthroat Trout at Creston NFH--Task: Acquire eggs and rear up to 100,000 Westslope Cutthroat trout annually for offsite mitigation stocking. Accomplishments: A total of 141,000 westslope cutthroat eggs (M012 strain) was acquired from the State of Montana Washoe Park State Fish Hatchery in May 2002 for this objective. We also received an additional 22,000 westslope cutthroat eggs, MO12 strain naturalized, from feral fish at Rogers Lake, Flathead County, Montana. The fish were reared using approved fish culture techniques as defined in the U.S. Fish and Wildlife Service, Fish Hatchery Management guidelines. Survival from the swim up fry stage to stocking was 95.6%. We achieved a 0.80 feed conversion this year on a new diet, Skretting ''Nutra Plus''. Post release survival and angler success is monitored annually by Montana Fish Wildlife and Parks (MFWP) and the Confederated Salish and Kootenai Tribe (CSKT). Stocking numbers and locations vary yearly based on results of biological monitoring and adaptive management. Mitigation Objective 2: Produce Rainbow Trout at Creston NFH--Task: Acquire and rear up to 100,000 Rainbow trout annually for offsite mitigation in closed basin waters. Accomplishments: A total of 54,000 rainbow trout eggs (Arlee strain) was acquired from the Ennis National Fish Hatchery in December 2002 for this objective. The fish were reared using approved fish culture techniques as defined in the U.S. Fish and Wildlife Service, Fish Hatchery Management guidelines. Survival from the swim up fry stage to stocking was 99.9%. We achieved a 0.79 feed conversion this year on a new diet, Skretting ''Nutra Plus''. Arlee rainbow trout are being used for this objective because the stocking locations are terminal basin reservoirs and habitat conditions and returns to the creel are unsuitable for native cutthroat. Post release survival and angler success is monitored annually by the Confederated Salish and Kootenai Tribe (CSKT). Stocking numbers and locations vary yearly based on results of biological monitoring and adaptive management.

US Fish and Wildlife Service Staff, (US Fish and Wildlife Service, Creston National Fish Hatchery, Kalispell, MT)

2004-02-01

57

Caracterización genética de lotes de peces usados en programas de repoblamiento y su importancia en la conservación genética en la piscicultura/ Genetic characterization of fish stocks used in stocking programas and their importance in the fish farm genetic conservation  

Scientific Electronic Library Online (English)

Full Text Available Abstract in spanish En las últimas décadas se ha verificado la desaparición de varias especies de peces debido principalmente a impactos generados por acciones humanas. Programas de repoblamiento vienen siendo cada vez más usados como métodos de conservación de la ictiofauna. Sin embargo, sin una correcta orientación genética y reproductiva de los lotes utilizados en estos programas, poblaciones naturales de peces y el ecosistema pueden ser afectados. El objetivo del siguiente estudi (more) o fue determinar la variabilidad genética de seis lotes de peces usados en programas de repoblamiento, mediante el marcador molecular RAPD. Se analizaron 180 alevines de tres especies de peces (Leporinus elongatus, Piaractus mesopotamicus y Prochilodus lineatus) en tres estaciones piscícolas, ubicadas en las ciudades de Rolândia, Andirá y Palotina en el estado de Paraná, Brasil. Los valores de variabilidad genética estimados por el porcentaje de fragmentos polimórficos y por el índice de diversidad de Shannon mostraron una alta variabilidad genética entre los lotes de L. elongatus y P. lineatus, debido posiblemente al efecto fundador y al manejo reproductivo adoptado en cada piscícola. Se determinó que existió baja diferenciación genética entre los lotes de P. mesopotamicus. Los resultados de este estudio posibilitaran el correcto manejo reproductivo y genético de los lotes de cada piscícola y la orientación objetiva de programas de repoblamiento, permitiendo la conservación de la variabilidad genética, factor de gran importancia en ambientes en cautiverio. Abstract in english In the last decades it has been verified the decrease and extinction of fish several species mainly to impacts generated by human actions. Stocking programs are being used as conservation methods of the ichthyofauna. However, without a correct genetic and reproductive orientation of the stocks used in these programs, natural fish populations and the ecosystem can be affected. The objective of the following study was to determine the genetic variability of six fish stocks (more) used in stocking programs, by means of the RAPD molecular marker. There were analyzed 180 juveniles of three fish species (Prochilodus lineatus, Piaractus mesopotamicus, and Leporinus elongatus) from three fish farms, located in the Rolândia, Andirá, and Palotina cities in Paraná state, Brazil. The genetic variability values estimated by the percentage of polymorphic fragments and by the Shannon diversity index showed a high genetic variability between the P. lineatus and L. elongatus stocks, due possibly to the founder effect and the reproductive management adopted in each fish farm. It was determined that low genetic differentiation existed among the P. mesopotamicus stocks. The results of this study facilitated the correct reproductive and genetic management of the stocks of each fish farm and the objective orientation of stocking programs, allowing the conservation of the genetic variability, factor of great importance in captivity environments.

Lopera Barrero, Nelson M; Pereira Ribeiro, Ricardo; Povh, Jayme A; Gomes, Patrícia C; Vargas, Lauro; Nogueira de Oliveira, Sheila

2008-12-01

58

Selenium bioaccumulation in stocked fish as an indicator of fishery potential in pit lakes on reclaimed coal mines in Alberta, Canada.  

Science.gov (United States)

Pit lakes are a common reclamation strategy for open pit mines; however, there is a concern about their water quality and suitability as fish habitat because they are often contaminated by metals or metalloids. This study assessed the exposure of fish and invertebrates to selenium (Se) and other metals and metalloids in pit lakes formed by open pit coal mining in Tertiary (thermal coal) and in Cretaceous (metallurgical coal) bedrock. Juvenile hatchery rainbow trout, Oncorhynchus mykiss, and brook trout, Salvelinus fontinalis, were stocked into two thermal coal pit lakes (water Se  15 ?g/L, high water Se). Se accumulation in stocked fish and concentrations in invertebrates were characterized over a period of 2 years. In the metallurgical pits, invertebrates had higher Se concentrations and fish accumulated Se to higher levels (exceeding USEPA tissue Se guidelines) than biota in the thermal pits. Rainbow and brook trout accumulated similar concentrations of Se in their muscle and exhibited a similar relationship between whole-body and muscle Se concentrations. These results may be used by resource managers to assess compliance with whole-body tissue Se guidelines and to determine if pit lakes in coal mining areas pose a significant Se risk to wildlife or human health. The high Se exposure in metallurgical coal pits indicates that under the current mining and reclamation strategy, these lakes are not suitable for management as recreational "put and take" fisheries. PMID:23665755

Miller, L L; Rasmussen, J B; Palace, V P; Sterling, G; Hontela, A

2013-05-12

59

Selenium bioaccumulation in stocked fish as an indicator of fishery potential in pit lakes on reclaimed coal mines in Alberta, Canada.  

UK PubMed Central (United Kingdom)

Pit lakes are a common reclamation strategy for open pit mines; however, there is a concern about their water quality and suitability as fish habitat because they are often contaminated by metals or metalloids. This study assessed the exposure of fish and invertebrates to selenium (Se) and other metals and metalloids in pit lakes formed by open pit coal mining in Tertiary (thermal coal) and in Cretaceous (metallurgical coal) bedrock. Juvenile hatchery rainbow trout, Oncorhynchus mykiss, and brook trout, Salvelinus fontinalis, were stocked into two thermal coal pit lakes (water Se < 2 ?g/L, low water Se) and two metallurgical coal pit lakes (water Se > 15 ?g/L, high water Se). Se accumulation in stocked fish and concentrations in invertebrates were characterized over a period of 2 years. In the metallurgical pits, invertebrates had higher Se concentrations and fish accumulated Se to higher levels (exceeding USEPA tissue Se guidelines) than biota in the thermal pits. Rainbow and brook trout accumulated similar concentrations of Se in their muscle and exhibited a similar relationship between whole-body and muscle Se concentrations. These results may be used by resource managers to assess compliance with whole-body tissue Se guidelines and to determine if pit lakes in coal mining areas pose a significant Se risk to wildlife or human health. The high Se exposure in metallurgical coal pits indicates that under the current mining and reclamation strategy, these lakes are not suitable for management as recreational "put and take" fisheries.

Miller LL; Rasmussen JB; Palace VP; Sterling G; Hontela A

2013-07-01

60

A two-stage biomass random effects model for stock assessment without catches: What can be estimated using only biomass survey indices?  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A simple two-stage biomass random effects population dynamics model is presented for carrying out fish stock assessments based on survey indices using no commercial catch information. Recruitment and biomass growth are modelled as random effects, reducing the number of model parameters while maintai...

Trenkel Verena

 
 
 
 
61

Pit telemetry as a method to study the habitat requirements of fish populations. Application to native and stocked trout movements  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Passive integrated transponder (PIT) technology was used to study the behaviour of fishes during the summer season in two headwater streams of northeastern Portugal. A total of 71 PIT tags (12 mm long x 2.1 mm diameter) were surgically implanted in 1+ stocked (39) and native (32) brown trout of two ...

Teixeira, Amílcar; Cortes, R.

62

PIT telemetry as a method to study the habitat requirements of fish populations: application to native and stocked trout movements  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Passive integrated transponder (PIT) technology was used to study the behaviour of fishes during the summer season in two headwater streams of northeastern Portugal. A total of 71 PIT tags (12 mm long x 2.1 mm diameter) were surgically implanted in 1+ stocked (39) and native (32) brown trout of two ...

Teixeira, Amílcar; Cortes, R.

63

Poor-data and data-poor species stock assessment using a Bayesian hierarchical approach.  

Science.gov (United States)

Appropriate inference for stocks or species with low-quality data (poor data) or limited data (data poor) is extremely important. Hierarchical Bayesian methods are especially applicable to small-area, small-sample-size estimation problems because they allow poor-data species to borrow strength from species with good-quality data. We used a hammerhead shark complex as an example to investigate the advantages of using hierarchical Bayesian models in assessing the status of poor-data and data-poor exploited species. The hammerhead shark complex (Sphyrna spp.) along the Atlantic and Gulf of Mexico coasts of the United States is composed of three species: the scalloped hammerhead (S. lewini), the great hammerhead (S. mokarran), and the smooth hammerhead (S. zygaena) sharks. The scalloped hammerhead comprises 70-80% of the catch and has catch and relative abundance data of good quality, whereas great and smooth hammerheads have relative abundance indices that are both limited and of low quality presumably because of low stock density and limited sampling. Four hierarchical Bayesian state-space surplus production models were developed to simulate variability in population growth rates, carrying capacity, and catchability of the species. The results from the hierarchical Bayesian models were considerably more robust than those of the nonhierarchical models. The hierarchical Bayesian approach represents an intermediate strategy between traditional models that assume different population parameters for each species and those that assume all species share identical parameters. Use of the hierarchical Bayesian approach is suggested for future hammerhead shark stock assessments and for modeling fish complexes with species-specific data, because the poor-data species can borrow strength from the species with good data, making the estimation more stable and robust. PMID:22073653

Jiao, Yan; Cortés, Enric; Andrews, Kate; Guo, Feng

2011-10-01

64

Poor-data and data-poor species stock assessment using a Bayesian hierarchical approach.  

UK PubMed Central (United Kingdom)

Appropriate inference for stocks or species with low-quality data (poor data) or limited data (data poor) is extremely important. Hierarchical Bayesian methods are especially applicable to small-area, small-sample-size estimation problems because they allow poor-data species to borrow strength from species with good-quality data. We used a hammerhead shark complex as an example to investigate the advantages of using hierarchical Bayesian models in assessing the status of poor-data and data-poor exploited species. The hammerhead shark complex (Sphyrna spp.) along the Atlantic and Gulf of Mexico coasts of the United States is composed of three species: the scalloped hammerhead (S. lewini), the great hammerhead (S. mokarran), and the smooth hammerhead (S. zygaena) sharks. The scalloped hammerhead comprises 70-80% of the catch and has catch and relative abundance data of good quality, whereas great and smooth hammerheads have relative abundance indices that are both limited and of low quality presumably because of low stock density and limited sampling. Four hierarchical Bayesian state-space surplus production models were developed to simulate variability in population growth rates, carrying capacity, and catchability of the species. The results from the hierarchical Bayesian models were considerably more robust than those of the nonhierarchical models. The hierarchical Bayesian approach represents an intermediate strategy between traditional models that assume different population parameters for each species and those that assume all species share identical parameters. Use of the hierarchical Bayesian approach is suggested for future hammerhead shark stock assessments and for modeling fish complexes with species-specific data, because the poor-data species can borrow strength from the species with good data, making the estimation more stable and robust.

Jiao Y; Cortés E; Andrews K; Guo F

2011-10-01

65

Pike ( Esox lucius L.) stocking as a biomanipulation tool .1. Effects on the fish population in Lake Lyng, Denmark  

DEFF Research Database (Denmark)

From 1990-1993 juvenile pike (Esox lucius) were stocked each spring in the eutrophic Lake Lyng (9.9 ha, max. depth 7.6 m, mean depth 2.4 m) in densities between 515 and 3616 pike ha(- 1). In 1989-90 the fish population consisted mainly of roach (Rutilus rutilus), rudd (Scardinius erythrophthalmus), perch (Perca fluviatilis) and ruffe (Gymnocephalus cernuus), and total fish biomass was estimated at 477 kg ha(-1). Prior to stocking pike was not present in the lake. Following the first year of stocking, the density of roach, rudd and ruffe fry expressed as catch per unit effort decreased significantly by 64 to 97%. In 1991 ruffe disappeared completely. The pike stocking did not affect the density of perch significantly. The growth of pike was high and also the growth of perch increased significantly from 1990 to 1991 (p 0.4). Pike survival was low in late August/early September. We suggest that growth of the piscivorous perch increased due to increased Secchi depth and a continuous high density of 0+ planktivores in the pelagic zone of the lake during the years of pike stocking, possibly caused by behaviourial changes and the forcing of the 0+ planktivores into the pelagic zone

Berg, SØren; Jeppesen, E.

1997-01-01

66

Microsatellite assessment of walrus (Odobenus rosmarus rosmarus) stocks in Canada  

Directory of Open Access Journals (Sweden)

Full Text Available Walruses in Canada are currently subdivided into seven stocks based on summering areas; Western Jones Sound (WJS), Baffin Bay (BB), Penny Strait-Lancaster Sound (PS-LS), North Foxe Basin (N-FB), Central Foxe Basin (C-FB), Hudson Bay Davis Strait (HB-DS) and Southern and Eastern Hudson Bay (SE-HB). In this study, walrus were sampled from six of the seven stocks (SE-HB samples were not available) and genotyped at 10 microsatellite loci. All stocks were genetically diverse (average heterozygosity of 0.58) with no evidence of inbreeding (average FIS of 0.03). We detected significant genetic differentiation among the stocks and a pattern of genetic spatial autocorrelation that suggests a moderate effect of geographic distance on gene flow among stocks. Bayesian clustering suggested the six recognized stocks were elements of two larger genetic clusters - a northern Arctic population (containing BB, WJS, and PS-LS stocks) and a central Arctic population (containing C-FB, N-FB, and HB-DS stocks). These populations are moderately differentiated (FST = 0.07), but based on evidence of contemporary movement from assignment tests, are not completely isolated. There was support for maintaining the WJS stock and a combined BB+PS-LS stock, although the latter conclusion is based on a small sample size. Similarly, there was some evidence suggesting separation of the Foxe Basin stocks from the HB-DS but not the N-FB from the C-FB stock. However, given that there are morphological and chemical differences between N-FB and C-FB stocks, there is currently insufficient evidence to support a revision of the current stock designations.

Aaron BA Shafer; Corey S Davis; David W Coltman; Robert EA Stewart

2013-01-01

67

78 FR 19446 - Marine Mammal Stock Assessment Reports  

Science.gov (United States)

...structure for Pacific Island stocks of melon- headed whales, pantropical spotted dolphins...science relating to the stock structure of melon-headed whales, spotted dolphins, and...appear to be at least two populations of melon- headed whales in the Hawaiian...

2013-04-01

68

Temporal Assessment of Growing Stock, Biomass and Carbon Stock of Indian Forests  

Energy Technology Data Exchange (ETDEWEB)

The dynamics of terrestrial ecosystems depends on interactions between carbon, nutrient and hydrological cycles. Terrestrial ecosystems retain carbon in live biomass (aboveground and belowground), decomposing organic matter, and soil. Carbon is exchanged naturally between these systems and the atmosphere through photosynthesis, respiration, decomposition, and combustion. Human activities change carbon stock in these pools and exchanges between them and the atmosphere through land-use, land-use change, and forestry. In the present study we estimated the wood (stem) biomass, growing stock (GS) and carbon stock of Indian forests for 1984 and 1994. The forest area, wood biomass, GS, and carbon stock were 63.86 Mha, 4327.99 Mm{sup 3}, 2398.19 Mt and 1085.06 Mt respectively in 1984 and with the reduction in forest area, 63.34 Mha, in 1994, wood biomass (2395.12 Mt) and carbon stock (1083.69 Mt) also reduced subsequently. The Conifers, of temperate region, stocked maximum carbon in their woods, 28.88 to 65.21 t C/ha, followed by Mangrove forests, 28.24 t C/ha, Dipterocarp forests, 28.00 t C/ha, and Shorea robusta forests, 24.07 t C/ha. Boswellia serrata, with 0.22 Mha forest area, stocked only 3.91 t C/ha. To have an idea of rate of carbon loss the negative changes (loss of forest area) in forest area occurred during 1984-1994 (10yrs) and 1991-1994 (4yrs) were also estimated. In India, land-use changes and fuelwood requirements are the main cause of negative change. Total 24.75 Mt C was lost during 1984-1994 and 21.35 Mt C during 1991-94 at a rate of 2.48 Mt C/yr and 5.35 Mt C/yr respectively. While in other parts of India negative change is due to multiple reasons like fuelwood, extraction of non-wood forest products (NWFPs), illicit felling etc., but in the northeastern region of the country shifting cultivation is the only reason for deforestation. Decrease in forest area due to shifting cultivation accounts for 23.0% of the total deforestation in India, with an annual loss of 0.93 Mt C/yr.

Manhas, R.K.; Negi, J.D.S.; Chauhan, P.S. [Forest Ecology and Environment Division, Forest Research Institute, Dehradun, 248 006, Uttaranchal (India); Kumar, R. [Forest Survey of India, Dehradun, 248 001, Uttaranchal (India)

2006-01-15

69

Biochemical Assessment of Selected Fresh Fish  

Directory of Open Access Journals (Sweden)

Full Text Available Ten fresh fish samples of different species (Mugil cephalus, Setipinna phasa, Coilia dussumieri, Scatophagus argus, Sillanopsis panijus, Arius caelatus, Hilsa ilisha, Polynemus paradiseus, Platicephalus indicus and Pelamys chiliensis) collected from Kuakata, Bangladesh were assessed biochemically (proximate composition, total volatile basic nitrogen, tri-methyl amine and pH). Moisture content of fresh fish varied over a range from 65.33 to 78.92%. Likewise, protein (8.58 to 19.06%), fat (6.12 to 12.99%) and ash (1.07 to 8.41%) content indicated wide variation in the ten fresh fish analysed. TVB-N and TMA-N values of fresh fish were found ranging between 10.92 ± 0.23 to 25.75 ± 0.80 mg N 100 g-1 and 7.70 ± 0.67 to 18.50 ± 0.77, respectively. The values of pH of the samples ranged from 7.03 ± 0.05 to 6.7 ± 0.07.

K. Azam; M.Y. Ali; M. Asaduzzaman; M.Z. Basher; M.M. Hossain

2004-01-01

70

Stock Assessment of the Common Octopus (Octopus vulgaris) in Monastir; the Mid-eastern Coast of Tunisia  

Directory of Open Access Journals (Sweden)

Full Text Available The common octopus, (Octopus vulgaris Cuvier, 1797) is widely distributed through the world. It represents an important resource with high economic value. It is exploited by trawl and by other gears such as trammel net, pots and it is also captured by diving. Although the multitude of assessment techniques, few fisheries cephalopods were well managed. In Tunisia, common octopus (Octopus vulgaris) is captured particularly in southern coast and the Sahel defined by three regions (Mahdia, Sousse and Monastir). Our study constitutes the first assessment stock in Monastir situated in the mid of the eastern coasts of Tunisia. Using surplus production models, an under fishing state of Octopus in the East of Tunisia is shown. This study confirms also the necessity of the incorporation of environmental parameters for a better explanation of the variability of common octopus abundance and the importance of these results in the assessment and management of this species.

Widien Khoufi; Chédia Jabeur; Amina Bakhrouf

2012-01-01

71

Environmental risk assessment of alkylphenols from offshore produced water on fish reproduction.  

UK PubMed Central (United Kingdom)

Concern has been raised over whether environmental release of alkylphenols (AP) in produced water (PW) discharges from the offshore oil industry could impose a risk to the reproduction of fish stocks in the North Sea. An environmental risk assessment (ERA) was performed to determine if environmental exposure to PW APs in North Sea fish populations is likely to be high enough to give effects on reproduction endpoints. The DREAM (Dose related Risk and Effect Assessment Model) software was used in the study and the inputs to the ERA model included PW discharge data, fate information of PW plumes, fish distribution information, as well as uptake and elimination information of PW APs. Toxicodynamic data from effect studies with Atlantic cod (Gadus morhua) exposed to APs were used to establish a conservative environmental risk threshold value for AP concentration in seawater. By using the DREAM software to 1) identify the areas of highest potential risk and 2) integrate fish movement and uptake/elimination rates of APs for the chosen areas we found that the environmental exposure of fish to APs from PW is most likely too low to affect reproduction in wild populations of fish in the North Sea. The implications related to risk management of offshore PW and uncertainties in the risk assessment performed are discussed.

Beyer J; Myhre LP; Sundt RC; Meier S; Tollefsen KE; Vabø R; Klungsøyr J; Sanni S

2012-04-01

72

The Stock Book 2004  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The Stock Book is the principal annual publication of the Marine Institute's Fisheries Science Services (FSS). Its purpose is to provide the latest impartial scientific advice on the commercially exploited fish stocks of interest to Ireland.

Marine Institute

73

The Stock Book 2007  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The Stock Book is the principal annual publication of the Marine Institute's Fisheries Science Services (FSS). Its purpose is to provide the latest impartial scientific advice on the commercially exploited fish stocks of interest to Ireland.

Marine Institute

74

The Stock Book 2003  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The Stock Book is the principal annual publication of the Marine Institute's Fisheries Science Services (FSS). Its purpose is to provide the latest impartial scientific advice on the commercially exploited fish stocks of interest to Ireland.

Marine Institute

75

Impact Assessment of the Role of Nigerian Stock Exchange on the Economic Development of Nigeria  

Directory of Open Access Journals (Sweden)

Full Text Available The stock exchange is a specialized market for the buying and selling of securities. These securities include stocks and shares which represent ownership interests in business, debentures and government bonds. The study assessed the impact that the Nigerian stock exchange has created on the development of the Nigerian economy. To achieve the objectives, this study reviewed stock exchange, its functions, activities, roles, and legislation. The advantages and disadvantages of listing on the stock market were also x-rayed. Also highlighted were the trading, clearing and settlement process of the Nigerian stock exchange and the short comings. The study concluded that for the Nigerian stock exchange to contribute significantly in the development of the Nigerian economy through mobilization and utilization of funds for expansion of business enterprises in the country, it should intensify efforts in creating public awareness as regards its services to the economy, effective investor education, fostering and stimulating speculation in the market and reforms that would compel investors to take due diligence when funds are to be raised by government to eliminate the buying and selling culture that exists in the market should be carried out.

Okoh, Lucky; Ekane, O. R.

2011-01-01

76

Welfare aspects of stocking density in farmed rainbow trout, assessed by behavioural and physiological methods  

DEFF Research Database (Denmark)

There is an increasing amount of interest in the welfare of fish from aquaculture. There are several aquaculture practices that may act as chronic stressors and therefore have the potential to negatively impact welfare. Stocking density has been highlighted as a particular welfare concern, from both an ethical and practical point of view. A quantity of research has been conducted on the relationship between stocking density and indicators of welfare in farmed rainbow trout Oncorhynchus mykiss. The studies to date have revealed that both low and high densities have the potential to detrimentally affect welfare in rainbow trout. Several studies have endeavoured to make specific recommendations for maximum stocking density limits for rainbow trout. However, wide discrepancies exist, highlighting the fact that it has been a challenge to identify density limits that promote optimal welfare and production in rainbow trout. This emphasises the significance of developing alternative methods that provide insight into the potential density limits that are optimal for welfare and performance in rainbow trout. Here, a behavioural method using two-tank systems was developed and applied. The twotank systems consisted of two identical tanks which were attached to each other with a doorway allowing the fish to move freely between the two tanks. By studying the spatial distribution of fish in two-tank systems stocked with different densities and the neuroendocrine stress levels of the fish, a density level was established that showed indications of crowding. The results revealed that a level of aversion to crowding had been reached at an absolute density of approximately 140 kg m–3. Additionally, the influence of the established density limit on physiological indicators of welfare and performance were investigated. At this density of 140 kg m–3, the lower oxygen consumption rates and lower quantity of scale loss collected from the tanks suggested reduced levels of social hierarchy related aggressive encounters. Higher brain serotonergic activity in the brain stem of individuals held at this density indicated elevated stress levels, despite low concentrations of plasma cortisol. The reduced energetic expenditure at 140 kg m–3 resulted in a better utilisation of ingested feed and hence growth performance. Taken together, despite the chronic stress levels at this density, the results showed that at this density the reduced energy expenditure, attributed to reduced aggressive social interactions, resulted in a better growth performance. Therefore, it may be concluded that application of the method using the two-tank systems provided new insight into an optimal stocking density limit for rainbow trout. Furthermore, the method presented here provides a promising tool for investigating stocking density levels in rainbow trout. Further development of the current method would consider it applicable for determining limits for a range of culture situations.

Laursen, Danielle Caroline

2013-01-01

77

Robustness of egg production methods as a fishery independent alternative to assess the Eastern Baltic cod stock (Gadus morhua callarias L.)  

DEFF Research Database (Denmark)

At present, several cod stocks are outside safe biological limits and are managed under recovery plans. For these stocks Total Allowable Catches (TAC's) are generally low and quotas are accompanied by a broad variety of technical measures influencing the fishing patterns. Consequently, the input data to stock assessment models relying on catch statistics from the commercial fisheries is potentially biased and the perception of stock status may be incorrect. Egg production methods (EPM) provide a fishery independent alternative. Additionally, they provide better estimates of stock reproductive potential (SRP). Eastern Baltic cod (Gad us morhua callarias L) has severely declined throughout the 2nd half of the 1980s and 1st half of the 1990s due to climate-driven adverse hydrographic conditions and high fishing intensity. Since 2007 the stock is managed under a long-term management plan and showed signs of recovery in most recent years. Since 1986. egg surveys have been carried! out regularly in the Bornholm Basin, the most important spawning area of Eastern Baltic cod since mid-1980s. In the present paper the robustness of EPM towards simplification of spawning parameters and toward; reduction of the number of egg surveys is tested applying three different methods requiring different numbers of egg surveys. We applied the annual egg production method (AEPM) requiring full egg survey coverage of the spawning season to estimate cod abundances in the Bornholm Basin. In addition, the daily fecundity reduction method (DFRM) and the daily egg production method (DEPM) were tested, the latter two methods requiring only single egg surveys, but require more complex reproduction input parameters. All three methods provided a comparable result, which was also expected as many spawning parameters were derived from the same underlying data sets. In a sensitivity analysis several input parameters were varied simultaneously up to 20% in both directions. EPM were! especially sensitive towards change.; in proportions of matur! e female s at age, whereas changes in the various fecundity parameters and spawning fraction were less influential. EPM results followed the large scale spawning stock trends of the Baltic International Trawl Survey index, whereas the year to year variations of the index were not captured to well. EPM yielded spawning stock sizes in the same order of magnitude as provided by a spatially down-scaled multi-species stock assessment model

Kraus, Gerd; Hinrichsen, Hans-Harald

2012-01-01

78

Evolutionary impact assessment: Accounting for the evolutionary consequences of fishing in an ecosystem approach to fisheries management  

DEFF Research Database (Denmark)

Managing fisheries resources to maintain healthy ecosystems is one of the main goals of the ecosystem approach to fisheries (EAF). While a number of international treaties call for the implementation of EAF, there are still gaps in the underlying methodology. One aspect that has received substantial scientific attention recently is fisheries-induced evolution (FIE). Increasing evidence indicates that intensive fishing has the potential to exert strong directional selection on life-history traits, behaviour, physiology, and morphology of exploited fish. Of particular concern is that reversing evolutionary responses to fishing can be much more difficult than reversing demographic or phenotypically plastic responses. Furthermore, like climate change, multiple agents cause FIE, with effects accumulating over time. Consequently, FIE may alter the utility derived from fish stocks, which in turn can modify the monetary value living aquatic resources provide to society. Quantifying and predicting the evolutionary effects of fishing is therefore important for both ecological and economic reasons. An important reason this is not happening is the lack of an appropriate assessment framework. We therefore describe the evolutionary impact assessment (EvoIA) as a structured approach for assessing the evolutionary consequences of fishing and evaluating the predicted evolutionary outcomes of alternative management options. EvoIA can contribute to EAF by clarifying how evolution may alter stock properties and ecological relations, support the precautionary approach to fisheries management by addressing a previously overlooked source of uncertainty and risk, and thus contribute to sustainable fisheries

Laugen, Ane T.; Engelhard, Georg H.

2012-01-01

79

Principles of fish welfare assessment in farm rearing conditions  

Directory of Open Access Journals (Sweden)

Full Text Available For several decades fish welfare has been subject of many researches, and the interest for this subject is connected with the fact that fish can feel pain and suffering. In addition to this stressors’ mechanisms of action and their consequences are similar in mammals and fish. Assessment of welfare for farmed fish is based on the same principles as for terrestrial farm animals. However, special methods of collecting data are needed due to morphological characteristics of fish and properties of their environment. In the world and in our country, researches of different ways of fish welfare assessment are being conducted, especially based on non-invasive techniques such as monitoring of behaviour. In this paper a review of basic principles and methods used in assessment of farmed fish welfare is given.

Reli? Renata R.; Hristov Slav?a V.; Vu?ini? Marijana M.; Poleksi? Vesna D.; Markovi? Zoran Z.

2010-01-01

80

Distribution of Anisakis larvae, identified by genetic markers, and their use for stock characterization of demersal and pelagic fish from European waters: an update.  

Science.gov (United States)

In the present paper, recent results obtained on the use of different distributions observed in larval species of Anisakis, genetically identified by means of allozyme markers, for stock characterization of demersal (Merluccius merluccius), small (Trachurus trachurus) and large pelagic (Xiphias gladius) finfish species in European waters, are reviewed and discussed. Several species of Anisakis were identified in the three fish hosts: A. simplex (s.s.), A. physeteris, A. typica, A. ziphidarum, A. pegreffii, A. brevispiculata and A. paggiae. Canonical discriminant analysis performed on all the samples of the three fish species collected in areas comprising their geographical range, according to the different species of Anisakis identified, showed distinct fish populations in European waters. In all the three fish hosts, the pattern of distribution of Anisakis larvae allowed discrimination of Mediterranean stocks from Atlantic stocks. In the case of swordfish, the possible existence of a southern Atlantic stock separated from a northern one is also suggested. Congruence and discordance with the population genetic data inferred from allozyme markers on the same samples of the three fish species are also discussed. PMID:17578592

Mattiucci, S; Abaunza, P; Damiano, S; Garcia, A; Santos, M N; Nascetti, G

2007-06-01

 
 
 
 
81

Diet of stocked and wild trout, Salmo trutta: Is there competition for resources?  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Stocked and native trout diet was assessed in two north-eastern Portugal headstreams during the summer season of three successive years (2000 to 2002). Significant differences were detected in the diet composition between stocked (age 1+) trout and distinct size-class of native trout. Stocked fish s...

Teixeira, Amílcar; Cortes, R.

82

Mapping of soil organic carbon stocks for spatially explicit assessments of climate change mitigation potential  

International Nuclear Information System (INIS)

[en] Current methods for assessing soil organic carbon (SOC) stocks are generally not well suited for understanding variations in SOC stocks in landscapes. This is due to the tedious and time-consuming nature of the sampling methods most commonly used to collect bulk density cores, which limits repeatability across large areas, particularly where information is needed on the spatial dynamics of SOC stocks at scales relevant to management and for spatially explicit targeting of climate change mitigation options. In the current study, approaches were explored for (i) field-based estimates of SOC stocks and (ii) mapping of SOC stocks at moderate to high resolution on the basis of data from four widely contrasting ecosystems in East Africa. Estimated SOC stocks for 0–30 cm depth varied both within and between sites, with site averages ranging from 2 to 8 kg m?2. The differences in SOC stocks were determined in part by rainfall, but more importantly by sand content. Results also indicate that managing soil erosion is a key strategy for reducing SOC loss and hence in mitigation of climate change in these landscapes. Further, maps were developed on the basis of satellite image reflectance data with multiple R-squared values of 0.65 for the independent validation data set, showing variations in SOC stocks across these landscapes. These maps allow for spatially explicit targeting of potential climate change mitigation efforts through soil carbon sequestration, which is one option for climate change mitigation and adaptation. Further, the maps can be used to monitor the impacts of such mitigation efforts over time. (letter)

2013-01-01

83

Automatic Fish Ageing (AFISA)  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Most of the fish stocks are assessed using age-based models, however age estimations using otoliths costs several million euros annually. In this context, Automatic Fish Ageing (EU Project) would provide means to standardize ageing among laboratories and build interpreted image databases ensuring th...

Mahe, Kelig; Parisi, Vincenc; Carbini, Sebastien; Soria, J.a.; Harbitz, A; De Pontual, Helene; Cotano, U; Songer, S

84

Towards sustainable fisheries of the Öresund cod (Gadus morhua) through sub-stock-specific assessment and management recommendations  

DEFF Research Database (Denmark)

Fisheries management traditionally relies on stock assessments assuming discrete populations within large administrational areas. However, failing to account for sub-stock structuring may result in overestimation of the stocks' true harvest potential and unsustainable exploitation of small stock elements. Atlantic cod (Gadus morhua) frequently occurs in spatially segregated populations, some of which exhibit fine-scaled stock structuring within current management boundaries. Here we use the locally spawning cod stock in the Sound (“Öresund”) as a case study, and perform a sub-stock-specific assessment to evaluate biological and economic effects of managing the Sound cod as a separate stock. Our results indicate that reducing exploitation pressure, particularly through technical regulations i.e. increasing gill-net mesh sizes, would not only enhance the stock age distribution, but yield long-term net benefits to the local gill-net fishery. Furthermore, our study emphasizes the need for developing sub-stock-specific management recommendations in order to ensure the maintenance of fisheries resources in general, and the persistence of sub-stock structuring in particular.

Lindegren, Martin; Waldo, Staffan

2013-01-01

85

International management strategies for a migratory fish stock :a bio-economic simulation model of the Norwegian spring-spawning herring  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In this paper, a three-country dynamic bio-economic simulation model is presented for the spring-spawning herring fishery. The international spring-spawning herring fishery, based on potentially one of the most valuable fish stocks in the world, is currently recovering from a severe depletion of the...

Bjørndal, Trond; Gordon, Daniel V.; Lindroos, Marko; Kaitala, Veijo

86

Assessing soil carbon stocks under pastures through orbital remote sensing  

Scientific Electronic Library Online (English)

Full Text Available Abstract in english The growing demand of world food and energy supply increases the threat of global warming due to higher greenhouse gas emissions by agricultural activity. Therefore, it is widely admitted that agriculture must establish a new paradigm in terms of environmental sustainability that incorporate techniques for mitigation of greenhouse gas emissions. This article addresses to the scientific demand to estimate in a fast and inexpensive manner current and potential soil organic (more) carbon (SOC) stocks in degraded pastures, using remote sensing techniques. Four pastures on sandy soils under Brazilian Cerrado vegetation in São Paulo state were chosen due to their SOC sequestration potential, which was characterized for the soil depth 0-50 cm. Subsequently, a linear regression analysis was performed between SOC and Leaf Area Index (LAI) measured in the field (LAIfield) and derived by satellite (LAIsatellite) as well as SOC and pasture reflectance in six spectra from 450 nm - 2350 nm, using the Enhanced Thematic Mapper (ETM+) sensor of satellite Landsat 7. A high correlation between SOC and LAIfield (R² = 0.9804) and LAIsatellite (R² = 0.9812) was verified. The suitability of satellite derived LAI for SOC determination leads to the assumption, that orbital remote sensing is a very promising SOC estimation technique from regional to global scale.

Szakács, Gabor Gyula Julius; Cerri, Carlos Clemente; Herpin, Uwe; Bernoux, Martial

2011-10-01

87

Assessing soil carbon stocks under pastures through orbital remote sensing  

Directory of Open Access Journals (Sweden)

Full Text Available The growing demand of world food and energy supply increases the threat of global warming due to higher greenhouse gas emissions by agricultural activity. Therefore, it is widely admitted that agriculture must establish a new paradigm in terms of environmental sustainability that incorporate techniques for mitigation of greenhouse gas emissions. This article addresses to the scientific demand to estimate in a fast and inexpensive manner current and potential soil organic carbon (SOC) stocks in degraded pastures, using remote sensing techniques. Four pastures on sandy soils under Brazilian Cerrado vegetation in São Paulo state were chosen due to their SOC sequestration potential, which was characterized for the soil depth 0-50 cm. Subsequently, a linear regression analysis was performed between SOC and Leaf Area Index (LAI) measured in the field (LAIfield) and derived by satellite (LAIsatellite) as well as SOC and pasture reflectance in six spectra from 450 nm - 2350 nm, using the Enhanced Thematic Mapper (ETM+) sensor of satellite Landsat 7. A high correlation between SOC and LAIfield (R² = 0.9804) and LAIsatellite (R² = 0.9812) was verified. The suitability of satellite derived LAI for SOC determination leads to the assumption, that orbital remote sensing is a very promising SOC estimation technique from regional to global scale.

Gabor Gyula Julius Szakács; Carlos Clemente Cerri; Uwe Herpin; Martial Bernoux

2011-01-01

88

A methology for the stocks assessments of cultivated oysters among along the French Atlantic coasts  

Digital Repository Infrastructure Vision for European Research (DRIVER)

An assessment of the reared stocks of the Pacific oyster (Crassostrea gigas ) has been recently conducted on the major French areas of molluscs culture. The methodology proposed included both estimates of densities obtained by subsampling in the field, and aerial photographs which covered the cultiv...

Bacher Cedric; Baud Jean-pierre; Bodoy Alain; Deslous-paoli Jean-marc; Dreno Jean-paul; Heral Maurice; Maurer Daniele

89

Magnitude and sources of uncertainties in soil organic carbon (SOC) stock assessments at various scales  

UK PubMed Central (United Kingdom)

Uncertainties in soil organic carbon (SOC) stock assessments are rarely quantified even though they are critical in determining the significance of the results. Previous studies on this topic generally focused on a single variable involved in the SOC stock calculation (SOC concentration, sampling depth, bulk density and rock fragment content) or on a single scale, rather than using an integrated approach (i.e. taking into account interactions between variables). This study aims to apply such an approach to identify and quantify the uncertainties in SOC stock assessments for different scales and spatial landscape units (LSU) under agriculture. The error propagation method (? method) was used to quantify the relative contribution of each variable and interaction involved to the final SOC stock variability. Monte Carlo simulations were used to cross-check the results. Both methods converged (r²=0.78). As expected, the coefficient of variation of the SOC stock increased across scales (from 5 to 35%), and was higher for grassland than for cropland. Although the main source of uncertainty in the SOC stock varied according to the scale and the LSU considered, the variability of SOC concentration (due to errors from the laboratory and to the high SOC spatial variability) and of the rock fragment content were predominant. When assessing SOC stock at the landscape scale, one should focus on the precision of SOC analyses from the laboratory, the reduction of SOC spatial variability (using bulk samples, accurate re-sampling, high sampling density or stratified sampling), and the use of equivalent masses for SOC stock comparison. The regional SOC stock monitoring of agricultural soils in southern Belgium allows the detection of an average SOC stock change of 20% within 11 years if very high rates of SOC stock changes occur (1 t C ha?¹ year?¹). Les erreurs associées aux estimations du stock de carbone organique dans le sol (COS) sont rarement quantifiées bien qu'elles puissent empêcher l'obtention de résultats significatifs. Les quelques études qui le font focalisent en général sur une seule variable nécessaire au calcul du stock de COS (concentration en COS, profondeur échantillonnée, densité apparente et contenu en fragments rocheux) ou sur une échelle spatiale particulière, sans utiliser d'approche intégrée (prenant en compte les interactions entre les variables). Cette étude a pour objectif d'utiliser une telle approche pour identifier et quantifier les incertitudes liées aux estimations de stock de COS à différentes échelles spatiales et pour diverses unités spatiales de paysages (USP) agricoles. La loi de propagation des erreurs (méthode ?) permet de quantifier la contribution relative de chaque variable et interaction à la variabilité finale du stock de COS. Les simulations de Monte Carlo sont utilisées pour la vérification croisée des résultats. Les deux méthodes ont convergé (r²= 0.78). Comme prévu, le coefficient de variation du stock de COS a proportionnellement augmenté avec l'échelle spatiale considérée (de 5 à 35%), et était plus élevé pour les cultures que pour les prairies. Bien que la principale source d'erreur sur le stock de COS soit fonction de l'échelle spatiale et du type d'USP considérés, la variabilité du contenu en COS (du fait des erreurs de laboratoire et de sa grande variabilité spatiale) et du contenu en fragments rocheux étaient prédominants. Lors de l'estimation des stocks de COS à l'échelle du paysage, l'attention devrait prioritairement porter sur la précision des analyses en COS du laboratoire, la réduction de la variabilité spatiale du COS (en utilisant des échantillons composites, un ré-échantillonnage précis, une densité d'échantillonnage élevée ou un échantillonnage stratifié), et sur l'utilisation de masses équivalentes pour comparer les stocks de COS. Le réseau régional de suivi des stocks de COS des sols agricoles dans le sud de la Belgique permet la détection d'un changement de stock de COS moyen de 20% en 11 ans pour u

Goidts E; vanWesemael B; Crucifix M

2009-10-01

90

ECOLOGICAL RISK ASSESSMENT: PROTECTING NORTHWEST ANADROMOUS SALMONID STOCKS  

Science.gov (United States)

Ecological risk assessment is usually defined as the process that evaluates the likelihood that adverse ecological effects are occurring, or may occur, as a result of exposure to one or mare stressors. he basic concept, while straightforward, is difficult to apply. trong reaction...

91

Complex dynamics analysis on fish stock harvested by two players with heterogeneous rationality  

Energy Technology Data Exchange (ETDEWEB)

This paper formulates a duopoly game model with heterogeneous expectations assuming that two players with asymmetric information harvest fish from a common fish ground and sell it in an imperfectly competitive market. We study the existence and stability of this system's positive equilibrium characterizing the sustainable use of the renewable resource. Then show the complex dynamics of this system in different parameters though numerical simulation. We finally show the influence of the adjustment speed of the harvesting quantity on the set of initial conditions which give non-negative trajectories converging to an equilibrium (called as a feasible set). When the player accelerates the adjustment speed in order to achieve initial advantage, we discover that it leads to instability of system and makes the system sink into the chaotic state and thus makes the resources exhaust more easily.

Gu Enguo [Department of Mathematics, South-Central University for Nationalities, Wuhan 430074 (China)], E-mail: guenguo@163.com

2009-10-30

92

A framework for assessing global change risks to forest carbon stocks in the United States.  

Science.gov (United States)

Among terrestrial environments, forests are not only the largest long-term sink of atmospheric carbon (C), but are also susceptible to global change themselves, with potential consequences including alterations of C cycles and potential C emission. To inform global change risk assessment of forest C across large spatial/temporal scales, this study constructed and evaluated a basic risk framework which combined the magnitude of C stocks and their associated probability of stock change in the context of global change across the US. For the purposes of this analysis, forest C was divided into five pools, two live (aboveground and belowground biomass) and three dead (dead wood, soil organic matter, and forest floor) with a risk framework parameterized using the US's national greenhouse gas inventory and associated forest inventory data across current and projected future Köppen-Geiger climate zones (A1F1 scenario). Results suggest that an initial forest C risk matrix may be constructed to focus attention on short- and long-term risks to forest C stocks (as opposed to implementation in decision making) using inventory-based estimates of total stocks and associated estimates of variability (i.e., coefficient of variation) among climate zones. The empirical parameterization of such a risk matrix highlighted numerous knowledge gaps: 1) robust measures of the likelihood of forest C stock change under climate change scenarios, 2) projections of forest C stocks given unforeseen socioeconomic conditions (i.e., land-use change), and 3) appropriate social responses to global change events for which there is no contemporary climate/disturbance analog (e.g., severe droughts in the Lake States). Coupling these current technical/social limits of developing a risk matrix to the biological processes of forest ecosystems (i.e., disturbance events and interaction among diverse forest C pools, potential positive feedbacks, and forest resiliency/recovery) suggests an operational forest C risk matrix remains elusive. PMID:24039889

Woodall, Christopher W; Domke, Grant M; Riley, Karin L; Oswalt, Christopher M; Crocker, Susan J; Yohe, Gary W

2013-09-10

93

A framework for assessing global change risks to forest carbon stocks in the United States.  

UK PubMed Central (United Kingdom)

Among terrestrial environments, forests are not only the largest long-term sink of atmospheric carbon (C), but are also susceptible to global change themselves, with potential consequences including alterations of C cycles and potential C emission. To inform global change risk assessment of forest C across large spatial/temporal scales, this study constructed and evaluated a basic risk framework which combined the magnitude of C stocks and their associated probability of stock change in the context of global change across the US. For the purposes of this analysis, forest C was divided into five pools, two live (aboveground and belowground biomass) and three dead (dead wood, soil organic matter, and forest floor) with a risk framework parameterized using the US's national greenhouse gas inventory and associated forest inventory data across current and projected future Köppen-Geiger climate zones (A1F1 scenario). Results suggest that an initial forest C risk matrix may be constructed to focus attention on short- and long-term risks to forest C stocks (as opposed to implementation in decision making) using inventory-based estimates of total stocks and associated estimates of variability (i.e., coefficient of variation) among climate zones. The empirical parameterization of such a risk matrix highlighted numerous knowledge gaps: 1) robust measures of the likelihood of forest C stock change under climate change scenarios, 2) projections of forest C stocks given unforeseen socioeconomic conditions (i.e., land-use change), and 3) appropriate social responses to global change events for which there is no contemporary climate/disturbance analog (e.g., severe droughts in the Lake States). Coupling these current technical/social limits of developing a risk matrix to the biological processes of forest ecosystems (i.e., disturbance events and interaction among diverse forest C pools, potential positive feedbacks, and forest resiliency/recovery) suggests an operational forest C risk matrix remains elusive.

Woodall CW; Domke GM; Riley KL; Oswalt CM; Crocker SJ; Yohe GW

2013-01-01

94

Potential Conflict between Fishermen and Giant Otter (Pteronura brasiliensis) Populations by Fishermen in Response to Declining Stocks of Arowana Fish (Osteoglossum bicirrhosum) in Northeastern Peru  

Directory of Open Access Journals (Sweden)

Full Text Available Giant otter (Pteronura brasiliensis) populations are increasing in many parts of the Peruvian Amazon, and are coming into contact with people more regularly. Giant otters are piscivores and fishermen often see them as potential competitors for fish stocks. We report on giant otter - fisherman conflict on the River Yanayacu. During informal discussions, we found that fishermen considered the giant otter a competitor for fish, and one of their main concerns was for the fisheries of arowana (Osteoglossum bicirrhosum). This fishery, for young arowanas for sale to the ornamental fish trade, is very important for the communities in the Pacaya-Samiria National Reserve, and fishermen believe that stocks of this species are declining. Although arowana can be preyed upon by giant otter, smaller fish are preferred and there is no evidence for giant otters impacting on populations of this species. We identify a need for more research into giant otter populations, arowana populations, the exploitation of arowana, and the diet of giant otters in northeastern Peru, to support conservation initiatives aimed at changing the perception of giant otters as competitors for fish.

Maribel Recharte; Mark Bowler; Richard Bodmer

2008-01-01

95

ASSESSMENT AND RECOGNITION OF STOCKS IN ACCOUNTING ACCORDING TO INTERNATIONAL STANDARD OF FINANCIAL REPORT IAS 2 – STOCKS  

Directory of Open Access Journals (Sweden)

Full Text Available In life accounts of an enterprise stocks represent a very important topic in the light of their c ost reflected in theprofit and loss account on the one hand, and the value of assets shown in the balance sheet on the other hand.In practice are met two categories of enterprises for which stock accounting are very important.The first category is represented by commodities traders, who have typically a single class of stock: goods. Inthis case the trader buys stocks for the purpose of resale. The second category is the producers of goods, which usuallymeet three categories of stocks: the raw materia ls, progress production and finished products.It is obviously that the assimilation process of accountancy standards culture will have repercussions onmedium and short term over the management controlling system, and over the informational system, in f orthwith time.The informational system, understood as an assembly of technical means and human resources, of methodologies andprocedures, of data collected and finally of information, which will have to be proper with a view to draw up a balancein accordance to the new accountancy rules.These changes will be especially of technical -accountancy nature and will foresee: the accounts plan, theconnections between different drawing up and collecting of data systems, the financial reports and the disclosure andreclassifying procedures

Elena HLACIUC; Dorel MATES; Marian SOCOLIUC

2009-01-01

96

CLI technical commission. Additional safety assessments within the EDF nuclear stock  

International Nuclear Information System (INIS)

[en] This slides presentation addresses additional safety assessments within the EDF nuclear stock. It describes the context and challenges of these assessments (institutional framework, European coherence, major objectives for EDF). It describes how EDF is organised to perform these assessments: a global project after Fukushima, assessments and tests which are beyond the existing safety referential, the three defence lines and their tests. It addresses the content of assessment reports for each topic (earthquake, flooding, loss of water, loss of electric supply, accident management). It indicates some improvements proposed after the first assessments. It describes the improvements concerning the Gravelines power plant. It recalls the assessment agenda, proposes a brief overview of events, comments the results of the third decennial visit of production unit no. 1 which comprised some proof test on the primary circuit, on the reactor vessel and on the reactor building

97

Identification and phylogenetic inferences on stocks of sharks affected by the fishing industry off the Northern coast of Brazil  

Directory of Open Access Journals (Sweden)

Full Text Available The ongoing decline in abundance and diversity of shark stocks, primarily due to uncontrolled fishery exploitation, is a worldwide problem. An additional problem for the development of conservation and management programmes is the identification of species diversity within a given area, given the morphological similarities among shark species, and the typical disembarkation of processed carcasses which are almost impossible to differentiate. The main aim of the present study was to identify those shark species being exploited off northern Brazil, by using the 12S-16S molecular marker. For this, DNA sequences were obtained from 122 specimens collected on the docks and the fish market in Bragança, in the Brazilian state of Pará. We identified at least 11 species. Three-quarters of the specimens collected were either Carcharhinus porosus or Rhizoprionodon sp, while a notable absence was the daggernose shark, Isogomphodon oxyrhyncus, previously one of the most common species in local catches. The study emphasises the value of molecular techniques for the identification of cryptic shark species, and the potential of the 12S-16S marker as a tool for phylogenetic inferences in a study of elasmobranchs.

Luis Fernando da Silva Rodrigues-Filho; Tainá Carreira da Rocha; Péricles Sena do Rêgo; Horacio Schneider; Iracilda Sampaio; Marcelo Vallinoto

2009-01-01

98

Mercury toxicology as assessed through fish scales.  

UK PubMed Central (United Kingdom)

Increasing pollution in water bodies is directly or indirectly related to increasing urbanization and indiscriminate disposal of agrochemical & industrial effluents. Heavy metals are one of the important categories of such pollutants and are causing serious hazards to non target species (Mwachiro and Druve1997). Their salts constitute a serious type of pollution in fresh water and being stable compounds; they are not readily removed by oxidation, precipitation or other processes and affect the activity in recipient animal (Jagadeesan and Vijayalakshmi 1998). Increase in the concentration of heavy metals has been reported in water of Vasai Creek, Maharastra and surface as well as groundwater of Delhi (Lokhande and Kelker 1999; Dixit et al. 2003). Recently, Food and Drug Adminstration (USFDA) and Environmental Protection Agency (USEPA) (2004) in their combined report recommended that pregnant women and lactating mothers should not eat shark, sword fish and king Mackerel as these fishes contain high levels of mercury.

Dua A; Gupta N

2005-06-01

99

Risk assessment in fish welfare, applications and limitations.  

UK PubMed Central (United Kingdom)

The Treaty of Amsterdam, in force since 1 May 1999, has established new ground rules for the actions of the European Union (EU) on animal welfare. It recognizes that animals are sentient beings and obliges the European Institutions to pay full regard to the welfare requirements of animals when formulating and implementing Community legislation. In order to properly address welfare issues, these need to be assessed in a scientific and transparent way. The principles of risk assessment in terms of transparency and use of available scientific data are probably well suited for this area. The application of risk assessment for terrestrial and aquatic animal welfare is a relatively new area. This paper describes the work developed in the context of the European Food Safety Authority (EFSA) opinions on the application of a risk assessment methodology to fish welfare. Risk assessment is a scientifically based process that seeks to determine the likelihood and consequences of an adverse event, which is referred to as a hazard. It generally consists of the following steps: (i) hazard identification, (ii) hazard characterisation, (iii) exposure assessment and (iv) risk characterisation. Different approaches can be used for risk assessments, such as qualitative, semi-quantitative and quantitative approaches. These are discussed in the context of fish welfare, using examples from assessments done to aquaculture husbandry systems and stunning/killing methods for farmed fish. A critical review of the applications and limitations of the risk methodology in fish welfare is given. There is a need to develop appropriate indicators of fish welfare. Yet, risk assessment methodology provides a transparent approach to identify significant hazards and support recommendations for improved welfare.

Müller-Graf C; Berthe F; Grudnik T; Peeler E; Afonso A

2012-02-01

100

Incorporating covariates into fisheries stock assessment models with application to Pacific herring.  

Science.gov (United States)

We present a framework for evaluating the cause of fishery declines by integrating covariates into a fisheries stock assessment model. This allows the evaluation of fisheries' effects vs. natural and other human impacts. The analyses presented are based on integrating ecological science and statistics and form the basis for environmental decision-making advice. Hypothesis tests are described to rank hypotheses and determine the size of a multiple covariate model. We extend recent developments in integrated analysis and use novel methods to produce effect size estimates that are relevant to policy makers and include estimates of uncertainty. Results can be directly applied to evaluate trade-offs among alternative management decisions. The methods and results are also broadly applicable outside fisheries stock assessment. We show that multiple factors influence populations and that analysis of factors in isolation can be misleading. We illustrate the framework by applying it to Pacific herring of Prince William Sound, Alaska (USA). The Pacific herring stock that spawns in Prince William Sound is a stock that has collapsed, but there are several competing or alternative hypotheses to account for the initial collapse and subsequent lack of recovery. Factors failing the initial screening tests for statistical significance included indicators of the 1989 Exxon Valdez oil spill, coho salmon predation, sea lion predation, Pacific Decadal Oscillation, Northern Oscillation Index, and effects of containment in the herring egg-on-kelp pound fishery. The overall results indicate that the most statistically significant factors related to the lack of recovery of the herring stock involve competition or predation by juvenile hatchery pink salmon on herring juveniles. Secondary factors identified in the analysis were poor nutrition in the winter, ocean (Gulf of Alaska) temperature in the winter, the viral hemorrhagic septicemia virus, and the pathogen Ichthyophonus hoferi. The implication of this result to fisheries management in Prince William Sound is that it may well be difficult to simultaneously increase the production of pink salmon and maintain a viable Pacific herring fishery. The impact can be extended to other commercially important fisheries, and a whole ecosystem approach may be needed to evaluate the costs and benefits of salmon hatcheries. PMID:18686586

Deriso, Richard B; Maunder, Mark N; Pearson, Walter H

2008-07-01

 
 
 
 
101

ASSESSMENT OF PLASTIC FLOWS AND STOCKS IN SERBIA USING MATERIAL FLOW ANALYSIS  

Directory of Open Access Journals (Sweden)

Full Text Available Material flow analysis (MFA) was used to assess the amounts of plastic materials flows and stocks that are annually produced, consumed, imported, exported, collected, recycled, and disposed in the landfills in Serbia. The analysis revealed that approximatelly 269,000 tons of plastic materials are directly disposed in uncontrolled landfills in Serbia without any preatretment, and that siginificant amounts of these materials have already accumulated in the landfills. The substantial amounts of landfilled plastics represent not only a loss of valuable recourses, but also pose a seriuos treath to the environment and human health, and if the trend of direct plastic landfilling is continued, Serbia will face with grave consecequnces.

Goran Vuji?; Nebojša M Jovi?i?; Milun Babi?; Nemanja S Stanisavljevi?; Bojan J Batini?; Aleksandar Pavlovi?

2010-01-01

102

Improving the assessment and management of the plaice stock complex between the North Sea and the Baltic Sea  

DEFF Research Database (Denmark)

Plaice in Kattegat and Skagerrak have traditionally been considered as one stock unit. However the collected information on biology and fishery in areas between the North and Baltic Seas suggest changes are needed in assessment units as well as in management areas. Plaice in Skagerrak (Division 20) is now considered to be closely associated with plaice in the North Sea and is proposed to be included in the North Sea plaice stock assessment, although it is recognized that local populations are present in the area. Therefore, specific management of the Skagerrak plaice is suggested. Plaice in Kattegat (Division 21), the Belts (Division 22), and the Sound (Division 23) is considered a stock unit and is proposed to be assessed as such. However, separate management by area is also suggested to assure the preservation of the local populations. Plaice in the Baltic (Divisions 24–32) is considered a stock unit and is proposed to be assessed and managed as such. Pragmatic options are suggested for empirical harvest control rules accounting for the dynamic of local abundance, using a survey?based biomass indicator. For the future, new scientific analyses should be developed to better inform the origin of the catches, provided that additional resources are allocated to the annual monitoring of different stocks and components. Such information would provide on?going quantitative information on the degree of mixing of the various components, potentially allowing a more accurate assessment, management, and conservation of the status of these

Ulrich, Clara; Boje, Jesper

2012-01-01

103

Effect of Different Stocking Ratio of Pangasid Catfish (Pangasius hypophthalmus) and Silver Carp (Hypophthalmicthys molitrix) on Better Water Quality Maintenance in Cat Fish Farming  

Directory of Open Access Journals (Sweden)

Full Text Available An experiment was conducted in Bangladesh Agricultural University for a period of three and half months from 1st May to 15th August 2002 to observe the effects of different stocking ratio of pangasid catfish and silver carp on better water quality maintenance and impacts of using fence in cat fish farming. Four treatments each with three replicates were used. The fishes were stocked at the rate of 120 fishes/decimal. The stocking ratios were: 100% pangasid catfish in Treatment 1(T1), 0% pangasid catfish plus 50% silver carp in Treatment 2 (T2), 0% pangasid catfish plus 40% silver carp in Treatment 3 (T3) and 50% pangasid catfish plus 50% silver carp in Treatment 4 (T4). Bamboo made fence were used in treatments 2 and 3 to keep the pangasid catfish and silver carp separately along the breadth wise considering the density of each species. Treatment 4 was set without fence. During the period of study, significant differences were found in dissolved oxygen, N03-N and chlorophyll-a concentrations among different stocking ratios of pangasid catfish and silver carp. The highest concentration of P04-P and NO3-N were found in T1 (2.7 and 3.1 mg L-1, respectively) followed by treatments T3, T2 and T4. This higher concentration of NO3-N and PO4-P enhanced the plankton biomass especially Cyanophyceae and Euglenophyceae in ponds of treatment 1 and identified dominant bloom forming cyanophytes were Microcystis and Gloeocapsa, which formed the heavy phytoplankton bloom throughout the culture period and deteriorated the water quality in pangasid catfish monoculture ponds (100% pangasid catfish). Whereas better water quality were found in composite culture. Among different stocking ratios, in composite culture 1:1 without fence (treatment 4) gave the best result in better water quality maintenances than 2:1 and 1:1 (with fence, treatment 3 and 2) ratios. In treatment 4 when the nutrients concentrations enhanced the phytoplankton production then silver carp grazed over phytoplankton throughout water body, which prevented the phytoplankton bloom formation during culture period and maintained a better environmental condition. Some algal bloom occurred in the portion of pangasid catfish in treatment 2 and treatment 3. It might be due to the grazing activity of silver carp over phytoplankton was restricted by the fence in those treatments. Considering the above facts composite culture of pangasid catfish and silver carp with 1:1 ratio and without fence may help in maintaining the good environmental condition of catfish farming through preventing the algal bloom.

Zannatul Ferdoushiand Farhana Haque

2006-01-01

104

DISPLACE: a dynamic, individual-based model for spatial fishing planning and effort displacement: Integrating underlying fish population models  

DEFF Research Database (Denmark)

We previously developed a spatially explicit, individual-based model (IBM) evaluating the bio-economic efficiency of fishing vessel movements between regions according to the catching and targeting of different species based on the most recent high resolution spatial fishery data. The main purpose was to test the effects of alternative fishing effort allocation scenarios related to fuel consumption, energy efficiency (value per litre of fuel), sustainable fish stock harvesting, and profitability of the fisheries. The assumption here was constant underlying resource availability. Now, an advanced version couples the vessel model to selected size-based population models and considers the underlying resource dynamics in the distribution and density patterns of the targeted stocks for the cases of Danish and German vessels harvesting the North Sea and Baltic fish stocks. The stochastic fishing process includes direct and local depletion by stock that is specific to the vessel catching power, which is proportionalto the encountered size-based population on the visited ground and is based on stock assessment and research survey data. The impact of the potential fishing effort displacement by vessels on the fish stocks, with resulting fishing mortality, and the vessels’ economic consequences are evaluated on high spatial and seasonal disaggregation levels by simulating different individual choices of vessel speed, fishing grounds and ports. All tested scenarios led to increased overall energy efficiency, except for the fishing closures that increased fuel consumption and costs for most of the vessels due to increased travel distance. On an individual scale, the simulations led to gains and losses due to either the technical interactions between vessels exploiting the same stocks or to the alteration of individual fishing patterns. We demonstrate that integrating the spatial activity of vessels and local fish stock abundance dynamics allow for interactions and more realistic predictions of fishermen behaviour, revenues and stock abundance

Bastardie, Francois; Nielsen, J. Rasmus

105

Available information for estimating reproductive potential of Northwest Atlantic groundfish stocks  

DEFF Research Database (Denmark)

The availability of data to improve indices of stock reproductive potential was reviewed for 42 Northwest Atlantic groundfish stocks comprising gadoids, flatfishes, redfishes and grenadiers.For many of the stocks, information on population parameters such as stock size and size/age composition estimates exists for three or more decades. Data on fish age, weight, maturity and sex ratios in the population have also been extensively collected, often allowing for establishment of time series of annual data that could be used for assessing spawning stock biomass and female spawning stock. However, possibilities for estimating stock potential egg production are constrained by scarcity of fecundity data. Data on fish condition, which can be useful in developing fecundity models, were seldom collected in earlier times, but have increased in recent decades. A data richness index, combining information about data quantity and quality, ranked most gadoid stocks as "data comprehensive" with a high proportion of stocks possessing some fecundity information. Flatfish stocks generally were "data moderate" owing to slightly shorter time series of data, while redfish and grenadier stocks in general were "data restricted". Published studies linking aspects of reproductive potential with parental characteristics and/or recruitment have become more frequent as "data richness" has improved for many stocks, but generally the prevalence of such studies remains low.

Tomkiewicz, Jonna; Morgan, M.J.

2003-01-01

106

Improving the assessment of instream flow needs for fish populations  

Energy Technology Data Exchange (ETDEWEB)

Instream flow requirements are one of the most frequent and most costly environmental issues that must be addressed in developing hydroelectric projects. Existing assessment methods for determining instream flow requirements have been criticized for not including all the biological response mechanisms that regulate fishery resources. A new project has been initiated to study the biological responses of fish populations to altered stream flows and to develop improved ways of managing instream flows. 21 refs., 3 figs.

Sale, M.J. (Oak Ridge National Lab., TN (USA)); Otto, R.G. (Otto (R.G.) and Associates, Arlington, VA (USA))

1991-01-01

107

Behavioral assay for assessing effects of pollutants on fish chemoreception  

Energy Technology Data Exchange (ETDEWEB)

Behavioral assays are sensitive to sublethal levels of pollution but they usually require highly trained personnel and long observation periods. We describe a system that combines the sensitivity of a behavioral assay with commercially available automated monitoring equipment. The observation system consists of a special aquarium coupled to a recirculating water system, and an Opto-Varimex-Aqua activity tracking meter (Columbus Instruments, Columbus, Ohio) interfaced to a microcomputer. The tracking meter forms an intersecting, planar grid of light beams which, when interrupted by fish movements, is translated into a digitized signal and fed to the computer. The assay is based on the response of fish to natural chemical stimuli such as food odors or pheromones. When these stimulus solutions are injected into the water circulation the response of the fish is monitored by the computer system, which is capable of discriminating and quantifying changes in eight parameters. Normal responses to stimuli are compared with the response of fish that have been exposed to pollutants. We have successfully used this technique to examine effects of reduced pH on the response of fathead minnows, Pimephales promelas, to chemical feeding stimuli. The system should be easily adapted to any laboratory concerned with testing for effects of toxic substances, and will identify effects of pollution that have thus far been difficult or impossible to assess.

Lemly, A.D.; Smith, R.J.

1986-04-01

108

Fish  

Science.gov (United States)

In this project you will learn about different types of fish. In your science journal write what you know about fish. Draw a picture of a common fish you might see where you live. On the handout record the information you learn during this unit. Click here to see the Angel Fish. Record information on Handout #1. Now go to the Clown Fish. ...

Hunter, Ms.

2009-07-07

109

[Sanitary and microbiological assessment of marketable fish of the Volga-Caspian Sea region  

UK PubMed Central (United Kingdom)

Opportunistic microbes, such as aeromonads, enterobacteria, and pseudomonads, which are responsible for spoiling fish during its storage and processing and capable to initiate pathological processes of fishes are common in the Volga-Caspian Sea region. Investigations demonstrated that it is necessary to develop new procedures for processing fish products, to carry out studies on regulation of microbiological criteria for assessing fish quality. This makes it necessary to make a bacteriological control of fish at all stages of its production.

Lartseva LV

1998-09-01

110

Stocking of Offsite Waters for Hungry Horse Dam Mitigation Creston National Fish Hatchery, FY 2006 Annual Report.  

Science.gov (United States)

A total of 350,000, M012 strain, westslope cutthroat trout (WCT) eggs were received from Montana Fish Wildlife & Parks (MFWP), Washoe Park State Fish Hatchery in June of 2005 to accomplish this fishery management objective. These eggs were incubated, hatc...

S. Hooley

2009-01-01

111

Assessment of the pelagic fish populations using CEN multi-mesh gillnets: consequences for the characterization of the fish communities  

Directory of Open Access Journals (Sweden)

Full Text Available The contribution of CEN standard pelagic nets to the assessment of fish communities is tested by comparing three metrics (species composition, species abundance, and size structures) measured in accordance with the standard (i.e. using benthic nets only) to those calculated from the total effort (i.e. including pelagic nets). Hydroacoustic surveys were used simultaneously to assess fish densities in the pelagic habitat. The results show that in most cases the pelagic nets did not provide any extra information about these three metrics. However, their inclusion in the calculation of CPUE and size structures may affect the picture of the fish communities, especially in lakes containing salmonid populations. This study highlights the need to sample pelagic fish when assessing fish communities in order to determine lake quality.

C. Deceliere-Vergès; J. Guillard

2008-01-01

112

The state of stocks of cod, whiting, sole and plaice on the west and southwest coasts of Ireland  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Stocks of cod, whiting, plaice and sole in ICES Divisions VIIb,c and VIIj,k are an important part of the Irish fishing resource yet, until 1993, were not subject to any assessment. Landings of these stocks in 1996 were valued at £8.6 million, representing 17% of the overall value of all Irish landin...

Wheatley, S. B.; Connolly, P. L.; Woods, F.; Keatinge, M.; Doherty, M.

113

Loss of genetic variability at the transferrin locus in five hatchery stocks of tambaqui (Colossoma macropomum)  

Directory of Open Access Journals (Sweden)

Full Text Available Knowledge and conservation of the genetic variability in stocks maintained as live gene banks have become a high priority task for Brazilian fish culture. The aim of the present survey was to assess the transferrin allelic diversity of five hatchery stocks of tambaqui (Colossoma macropomum). The tambaqui stock from Pentecoste, the oldest maintained in Brazilian hatchery stations, retained three of the six alleles detected in wild populations of tambaqui from the Amazon River. Other hatchery stocks, directly or indirectly derived from the Pentecoste stock, did not show transferrin allelic variability. Insufficient number of founders and genetic drift due to sampling errors seem to be the main causes leading to loss of genetic diversity in tambaqui hatchery stocks. Appropriate management strategies are required in order to improve the genetic potential of tambaqui stocks in Brazil.

Calcagnotto Daniela; Toledo-Filho Silvio de Almeida

2000-01-01

114

Assessing the impact of fishing in shallow rocky reefs: A multivariate approach to ecosystem management.  

UK PubMed Central (United Kingdom)

In this paper we develop a tool to assess the impact of fishing on ecosystem functioning in shallow rocky reefs. The relationships between biological parameters (fishes, sea urchins, seaweeds), and fishing activities (fish traps, boats, land-based fishing, spearfishing) were tested in La Palma island (Canary Islands). Data from fishing activities and biological parameters were analyzed using principal component analyses. We produced two models using the first component of these analyses. This component was interpreted as a new variable that described the fishing pressure and the conservation status at each studied site. Subsequently the scores on the first axis were mapped using universal kriging methods and the models obtained were extrapolated across the whole island to display the expected fishing pressure and conservation status more widely. The fishing pressure and conservation status models were spatially related; zones where fishing pressure was high coincided with zones in the unhealthiest ecological state.

Sangil C; Martín-García L; Clemente S

2013-09-01

115

Greenland Halibut in Upernavik: a preliminary study of the importance of the stock for the fishing populace : A study undertaken under the Greenland Climate Research Centre  

DEFF Research Database (Denmark)

This report presents research undertaken with the belief that a need exists for better understanding of the social and cultural importance of the Greenland Halibut (Reinhardtius hippoglossoides) fishery to Greenlanders. It was decided the research would focus on one of three coastal Greenland Halibut fishery districts: Upernavik. Upernavik was chosen mgiven the critical importance of Greenland halibut for local fishers and area residents. The best method for presenting a combination of social and fishery data takes the form of a fishery profile. Additionally, given that the government of Greenland is currently in the midst of proposing changes to the Halibut management structure, the report focuses specifically on potential social impacts of the fishery management plan to coastal fishers. The degree and consequence of any impact is a function of the characteristics of the fishing community. The critical point is the vulnerability of the community to negative repercussions of the management action and the resilience the community has in being able to absorb these repercussions. Upernavik and Greenlandic fisheries communities are known to be remote and have limited economic opportunities for residents. Consequently, it is important to understand the adaptability and vulnerability of the community in order to successfully anticipate impacts. Greenland halibut is the most important commercial fish stock for Upernavik residents. In 2010 there were more than 385 fishermen with official licenses for Greenland halibut in Upernavik. There are up to an additional 75 who also fish, however, without paying the license fee. This means that almost half of working age men fish for halibut in the Upernavik district. Fishing is extremely important in Upernavik for its role in the local, mixed economy. Fishing often provides the cash needed for materials needed for work (hunting and fishing equipment such as bullets, nets, snowmobiles, etc.) and daily living (housing, transport, television, food, etc). Fishing also supports the important local cultural practice of meeting social obligations and reciprocity such as through kødgaver (gifting of meat), a practice which remains both culturally and economically important in the smaller settlements. Currently, the government of Greenland is proposing changes to the management of Greenland halibut for the coastal fishers, including the closing the fishery to new entrants in 2012. Additional changes include the introduction of ITQs for large boats. With little discussion of where locals will work and live if they can not earn an income from the fishery, or discussion of how the communities may be impacted by the potential consolidation of quota shares into fewer hands (as is seen in all ITQ fisheries), the report suggests that management follows accepted practices of good governance as it introduces its new Greenland halibut plan. Good governance is participatory and is based upon, among other points, social equity, responsiveness, and transparency. It is also responsive to the present and future needs of society. Since the plan has not yet been implemented, however, there is still time to follow good governance practices for the sustainability of not only the Greenland halibut stock, but also for Greenlandic society.

Delaney, Alyne E.; Becker Jakobsen, Rikke

2012-01-01

116

Assessment of exotic fish disease introduction and establishment in the United Kingdom via live fish transporters.  

Science.gov (United States)

Live fish transporters returning empty from mainland Europe may mechanically introduce exotic pathogens and parasites to the UK. A qualitative risk assessment approach was adopted to investigate the likelihood of introduction and establishment in rainbow trout farms of viral haemorrhagic septicaemia (VHS), infectious haematopoietic necrosis (IHN) and Gyrodactylus salaris via this route. A scenario tree was developed and estimates made for the likelihood of each step based on a review of the available information. The level of uncertainty associated with each step was qualitatively assessed. The likelihood of a lorry becoming contaminated with any of the 3 hazards was only greater than negligible if the lorry made movements between farms in mainland Europe. In these circumstances, the overall likelihood of introduction and establishment was extremely low (would occur very rarely), extremely low to negligible and very low (would occur rarely) for VHS, IHN and G. salaris, respectively. A high level of uncertainty existed due to the lack of data on farm-level prevalence, minimum infectious dose (of the viral hazards) and the large variability in duration and conditions of transport. A telephone survey of live fish transporters found that cleaning and disinfection practices after return to the UK were implemented. Currently, no UK-based transporters make movements between farms in mainland Europe. Thus, the likelihood that UK-owned transporters may become infected is negligible. Changes in the way in which UK-based live fish transporters operate in mainland Europe need to be monitored and development of a code of practice to minimise the risk of disease introduction considered. PMID:19326789

Peeler, E J; Thrush, M A

2009-02-12

117

Assessment of exotic fish disease introduction and establishment in the United Kingdom via live fish transporters.  

UK PubMed Central (United Kingdom)

Live fish transporters returning empty from mainland Europe may mechanically introduce exotic pathogens and parasites to the UK. A qualitative risk assessment approach was adopted to investigate the likelihood of introduction and establishment in rainbow trout farms of viral haemorrhagic septicaemia (VHS), infectious haematopoietic necrosis (IHN) and Gyrodactylus salaris via this route. A scenario tree was developed and estimates made for the likelihood of each step based on a review of the available information. The level of uncertainty associated with each step was qualitatively assessed. The likelihood of a lorry becoming contaminated with any of the 3 hazards was only greater than negligible if the lorry made movements between farms in mainland Europe. In these circumstances, the overall likelihood of introduction and establishment was extremely low (would occur very rarely), extremely low to negligible and very low (would occur rarely) for VHS, IHN and G. salaris, respectively. A high level of uncertainty existed due to the lack of data on farm-level prevalence, minimum infectious dose (of the viral hazards) and the large variability in duration and conditions of transport. A telephone survey of live fish transporters found that cleaning and disinfection practices after return to the UK were implemented. Currently, no UK-based transporters make movements between farms in mainland Europe. Thus, the likelihood that UK-owned transporters may become infected is negligible. Changes in the way in which UK-based live fish transporters operate in mainland Europe need to be monitored and development of a code of practice to minimise the risk of disease introduction considered.

Peeler EJ; Thrush MA

2009-02-01

118

National guidance for assessing the risks of consuming chemically contaminated fish  

Energy Technology Data Exchange (ETDEWEB)

The EPA`s Fish Contamination Program (FCP) provides technical assistance and guidance to State, Federal, and Tribal agencies for assessing human health risks associated with dietary exposure to chemically contaminated noncommercial freshwater and estuarine fish and shellfish. the program includes guidance documents which may be used for developing fish consumption advisories. One series of guidance documents, titled Guidance for Assessing Chemical Contaminant Data for Use in Fish Advisories, are designed to provide the States, Tribes, and other interested parties with a scientifically defensible, cost effective methodology for developing, implementing, managing and communicating risk-base fish consumption advisories. The fist document of the series, Volume 1: Fish Sampling and Analysis (September 1993), provides recommended methods for sampling strategies, field collection procedure, chemical analysis, data management and profiles of 24 chemicals which have been identified as analyses of concern with respect to dietary exposure to chemical contaminants in fish. volume 2: Risk Assessment and Fish Consumption Limits (June 1994), provides chemical specific risk based fish consumption limits for 24 analyses based on the amount and frequency of individual fish consumption patterns. Specific fish consumption limits and advice for the general population and women of child-bearing age are provided. Volume 3: Risk Management, is scheduled for release in late 1 994. This document will review management options which should be considered in the development of fish consumption advisories. Volume 4: Risk Communication, is scheduled for release in the fall of 1994. This document will address effective communication of fish consumption advisories to targeted audiences.

Bigler, J.

1994-12-31

119

Peat Depth Assessment Using Airborne Geophysical Data for Carbon Stock Modelling  

Science.gov (United States)

The Kyoto Agreement demands that all signatory countries have an inventory of their carbon stock, plus possible future changes to this store. This is particularly important for Ireland, where some 16% of the surface is covered by peat bog. Estimates of soil carbon stores are a key component of the required annual returns made by the Irish and UK governments to the Intergovernmental Panel on Climate Change. Saturated peat attenuates gamma-radiation from underlying rocks. This effect can be used to estimate the thickness of peat, within certain limits. This project examines this relationship between peat depth and gamma-radiation using airborne geophysical data generated by the Tellus Survey and newly acquired data collected as part of the EU-funded Tellus Border project, together encompassing Northern Ireland and the border area of the Republic of Ireland. Selected peat bog sites are used to ground truth and evaluate the use of airborne geophysical (radiometric and electromagnetic) data and validate modelled estimates of soil carbon, peat volume and depth to bedrock. Data from two test line sites are presented: one in Bundoran, County Donegal and a second line in Sliabh Beagh, County Monaghan. The plane flew over these areas at different times of the year and at a series of different elevations allowing the data to be assessed temporally with different soil/peat saturation levels. On the ground these flight test lines cover varying surface land use zones allowing future extrapolation of data from the sites. This research applies spatial statistical techniques, including uncertainty estimation in geostatistical prediction and simulation, to investigate and model the use of airborne geophysical data to examine the relationship between reduced radioactivity and peat depth. Ground truthing at test line locations and selected peat bog sites involves use of ground penetrating radar, terrestrial LiDAR, peat depth probing, magnetometry, resistivity, handheld gamma-ray spectrometry, moisture content and rainfall monitoring combined with a real-time Differential Global Positioning System (DGPS) to monitor temporal and spatial variability of bog elevations. This research will assist in determining the accuracy and limitations of modelling soil carbon and changes in peat stocks by investigating the attenuation of gamma-radiation from underlying rocks. Tellus Border is supported by the EU INTERREG IVA programme, which is managed by the Special EU Programmes Body in Northern Ireland, the border Region of Ireland and western Scotland. The Tellus project was funded by the Northern Ireland Development of Enterprise Trade and Investment and by the Rural Development Programme through the Northern Ireland Programme for Building Sustainable Prosperity.

Keaney, Antoinette; McKinley, Jennifer; Ruffell, Alastair; Robinson, Martin; Graham, Conor; Hodgson, Jim; Desissa, Mohammednur

2013-04-01

120

Wavelet decomposition and regime shifts. Assessing the effects of crude oil shocks on stock market returns  

Energy Technology Data Exchange (ETDEWEB)

While there is a large body of empirical studies on the relationship between crude oil price changes and stock market returns, they have failed to achieve a consensus on this subject. In this paper, we combine wavelet analysis and Markov Switching Vector Autoregressive (MS-VAR) approach to explore the impact of the crude oil (CO) shocks on the stock market returns for UK, France and Japan over the period from January 1989 to December 2007. Our procedure involves the estimation of the extended MS-VAR model in order to investigate the importance of the resultant wavelet filtering series (after removing random components) in determining the behavior of the stock market volatilities. We show that CO shocks do not affect the recession stock market phases (except for Japan). However, they significantly reduce moderate and/or expansion stock market phases temporarily. Moreover, this negative relationship appears to be more pronounced during the pre-1999 period. The empirical findings will prove extremely useful to investors who need to understand the exact effect of international oil changes on certain stocks prices as well as for policy managers who need a more thorough evaluation about the efficiency of hedging policies affected by oil price changes. (author)

Jammazi, Rania; Aloui, Chaker [International finance group-Tunisia, Faculty of Management and Economic Sciences of Tunis, Boulevard du 7 novembre, El Manar University, B.P. 248, C.P. 2092, Tunis Cedex (Tunisia)

2010-03-15

 
 
 
 
121

Wavelet decomposition and regime shifts: Assessing the effects of crude oil shocks on stock market returns  

Energy Technology Data Exchange (ETDEWEB)

While there is a large body of empirical studies on the relationship between crude oil price changes and stock market returns, they have failed to achieve a consensus on this subject. In this paper, we combine wavelet analysis and Markov Switching Vector Autoregressive (MS-VAR) approach to explore the impact of the crude oil (CO) shocks on the stock market returns for UK, France and Japan over the period from January 1989 to December 2007. Our procedure involves the estimation of the extended MS-VAR model in order to investigate the importance of the resultant wavelet filtering series (after removing random components) in determining the behavior of the stock market volatilities. We show that CO shocks do not affect the recession stock market phases (except for Japan). However, they significantly reduce moderate and/or expansion stock market phases temporarily. Moreover, this negative relationship appears to be more pronounced during the pre-1999 period. The empirical findings will prove extremely useful to investors who need to understand the exact effect of international oil changes on certain stocks prices as well as for policy managers who need a more thorough evaluation about the efficiency of hedging policies affected by oil price changes.

Jammazi, Rania, E-mail: jamrania2@yahoo.f [International finance group-Tunisia, Faculty of Management and Economic Sciences of Tunis, Boulevard du 7 novembre, El Manar University, B.P. 248, C.P. 2092, Tunis Cedex (Tunisia); Aloui, Chaker, E-mail: chaker.aloui@fsegt.rnu.t [International finance group-Tunisia, Faculty of Management and Economic Sciences of Tunis, Boulevard du 7 novembre, El Manar University, B.P. 248, C.P. 2092, Tunis Cedex (Tunisia)

2010-03-15

122

Assessment of an automated fish counter in a Canadian river  

UK PubMed Central (United Kingdom)

Abstract. In order to assess the accuracy and reliability of automated fish counters for counting adult Atlantic salmon, Salmo salar L., a ‘Logie' resistivity counter was installed in late June 1989 in the control dam above the fishway in Northeast River, Placentia, Newfoundland, Canada. The counter was in operation for 26 days (1-26 July). The accuracy of daily counts recorded by the counter was verified by visual counts of Atlantic salmon released from a trap located downstream of the counter and immediately above the fishway. All the fish released from the trap had to pass over the counter. A total of 517 salmon (mainly grilse) was released from the trap and the net number of upstream migrants recorded by the counter was also 517. This is the first test and use of an open-channel counter in eastern Canada. The results suggest that some counting fences and fishways may be easily adapted for installation of automated counters and that counters offer a cost-effective means of counting adult Atlantic salmon.

REDDIN DG; O'CONNELL MF; DUNKLEY DA

1992-01-01

123

Assessment of Sr, Cs and K radionuclide equilibrium concentration factors in Danube fish  

International Nuclear Information System (INIS)

Measurements based upon fallout activity were carried out for assessing some equilibrium concentration factors in fish of the Austrian region of the Danube river, the radionuclides being Cs-137, Sr-90 and K-40. Mean values were found as 250 for Cs-137 and 7 for Sr-90 in fish tissue and as 350 for Sr-90 in fish bone, and 1.2x103 for K-40. Well proved log-normal distributions for Cs-137 in fish tissue and Sr-90 in fish bone and a normal distribution for K-40 satisfactorily describe the scattering of data. (orig.)

1988-01-01

124

Assessment of Sr, Cs and K radionuclide equilibrium concentration factors in Danube fish  

Energy Technology Data Exchange (ETDEWEB)

Measurements based upon fallout activity were carried out for assessing some equilibrium concentration factors in fish of the Austrian region of the Danube river, the radionuclides being Cs-137, Sr-90 and K-40. Mean values were found as 250 for Cs-137 and 7 for Sr-90 in fish tissue and as 350 for Sr-90 in fish bone, and 1.2x10/sup 3/ for K-40. Well proved log-normal distributions for Cs-137 in fish tissue and Sr-90 in fish bone and a normal distribution for K-40 satisfactorily describe the scattering of data.

Tschurlovits, M.; Streisselberger, F.

1988-03-01

125

Assessment of dietary fish consumption in pregnancy: comparing one-, four- and thirty-six-item questionnaires.  

UK PubMed Central (United Kingdom)

OBJECTIVE: Fish consumption influences a number of health outcomes. Few studies have directly compared dietary assessment methods to determine the best approach to estimating intakes of fish and its component nutrients, including DHA, and toxicants, including methylmercury. Our objective was to compare three methods of assessing fish intake. DESIGN: We assessed 30 d fish intake using three approaches: (i) a single question on total fish consumption; (ii) a brief comprehensive FFQ that included four questions about fish; and (iii) a focused FFQ with thirty-six questions about different finfish and shellfish. SETTING: Obstetrics practices in Boston, MA, USA. SUBJECTS: Fifty-nine pregnant women who consumed ?2 monthly fish servings. RESULTS: Estimated intakes of fish, DHA and Hg were lowest with the one-question screener and highest with the thirty-six-item fish questionnaire. Estimated intake of DHA with the thirty-six-item questionnaire was 4·4-fold higher (97 v. 22 mg/d), and intake of Hg was 3·8-fold higher (1·6 v. 0·42 ?g/d), compared with the one-question screener. Plasma DHA concentration was correlated with fish intake assessed with the one-question screener (Spearman r = 0·27, P = 0·04), but not with the four-item FFQ (r = 0·08, P = 0·54) or the thirty-six-item fish questionnaire (r = 0·01, P = 0·93). In contrast, blood and hair Hg concentrations were similarly correlated with fish and Hg intakes regardless of the assessment method (r = 0·35 to 0·52). CONCLUSIONS: A longer questionnaire provides no advantage over shorter questionnaires in ranking intakes of fish, DHA and Hg compared with biomarkers, but estimates of absolute intakes can vary by as much as fourfold across methods.

Oken E; Guthrie LB; Bloomingdale A; Gillman MW; Olsen SF; Amarasiriwardena CJ; Platek DN; Bellinger DC; Wright RO

2013-07-01

126

Atlas of Irish Groundfish Trawl Surveys: Supporting fish stock assessment and new ecosystem advice  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This Atlas presents the key results from the Irish groundfish survey programme which is carried out annually in the waters around Ireland, and the Deepwater programme conducted between 2006 and 2009. The various groundfish surveys are described together with the gear used and the areas surveyed. A...

Marine Institute

127

Comparison of methods for measuring and assessing carbon stocks and carbon stock changes in terrestrial carbon pools. How do the accuracy and precision of current methods compare? A systematic review protocol  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Climate change and high rates of global carbon emissions have focussed attention on the need for high-quality monitoring systems to assess how much carbon is present in terrestrial systems and how these change over time. The choice of system to adopt should be guided by good science. There is a growing body of scientific and technical information on ground-based and remote sensing methods of carbon measurement. The adequacy and comparability of these different systems have not been fully evaluated. Methods A systematic review will compare methods of assessing carbon stocks and carbon stock changes in key land use categories, including, forest land, cropland, grassland, and wetlands, in terrestrial carbon pools that can be accounted for under the Kyoto protocol (above- ground biomass, below-ground biomass, dead wood, litter and soil carbon). Assessing carbon in harvested wood products will not be considered in this review. Discussion Developing effective mitigation strategies to reduce carbon emissions and equitable adaptation strategies to cope with increasing global temperatures will rely on robust scientific information that is free from biases imposed by national and commercial interests. A systematic review of the methods used for assessing carbon stocks and carbon stock changes will contribute to the transparent analysis of complex and often contradictory science.

Petrokofsky Gillian; Kanamaru Hideki; Achard Frédéric; Goetz Scott J; Joosten Hans; Holmgren Peter; Lehtonen Aleksi; Menton Mary CS; Pullin Andrew S; Wattenbach Martin

2012-01-01

128

Effects of human population density and proximity to markets on coral reef fishes vulnerable to extinction by fishing.  

Science.gov (United States)

Coral reef fisheries are crucial to the livelihoods of tens of millions of people; yet, widespread habitat degradation and unsustainable fishing are causing severe depletion of stocks of reef fish. Understanding how social and economic factors, such as human population density, access to external markets, and modernization interact with fishing and habitat degradation to affect fish stocks is vital to sustainable management of coral reef fisheries. We used fish survey data, national social and economic data, and path analyses to assess whether these factors explain variation in biomass of coral reef fishes among 25 sites in Solomon Islands. We categorized fishes into 3 groups on the basis of life-history characteristics associated with vulnerability to extinction by fishing (high, medium, and low vulnerability). The biomass of fish with low vulnerability was positively related to habitat condition. The biomass of fishes with high vulnerability was negatively related to fishing conducted with efficient gear. Use of efficient gear, in turn, was strongly and positively related to both population density and market proximity. This result suggests local population pressure and external markets have additive negative effects on vulnerable reef fish. Biomass of the fish of medium vulnerability was not explained by fishing intensity or habitat condition, which suggests these species may be relatively resilient to both habitat degradation and fishing. PMID:23282178

Brewer, T D; Cinner, J E; Green, A; Pressey, R L

2013-01-02

129

Effects of human population density and proximity to markets on coral reef fishes vulnerable to extinction by fishing.  

UK PubMed Central (United Kingdom)

Coral reef fisheries are crucial to the livelihoods of tens of millions of people; yet, widespread habitat degradation and unsustainable fishing are causing severe depletion of stocks of reef fish. Understanding how social and economic factors, such as human population density, access to external markets, and modernization interact with fishing and habitat degradation to affect fish stocks is vital to sustainable management of coral reef fisheries. We used fish survey data, national social and economic data, and path analyses to assess whether these factors explain variation in biomass of coral reef fishes among 25 sites in Solomon Islands. We categorized fishes into 3 groups on the basis of life-history characteristics associated with vulnerability to extinction by fishing (high, medium, and low vulnerability). The biomass of fish with low vulnerability was positively related to habitat condition. The biomass of fishes with high vulnerability was negatively related to fishing conducted with efficient gear. Use of efficient gear, in turn, was strongly and positively related to both population density and market proximity. This result suggests local population pressure and external markets have additive negative effects on vulnerable reef fish. Biomass of the fish of medium vulnerability was not explained by fishing intensity or habitat condition, which suggests these species may be relatively resilient to both habitat degradation and fishing.

Brewer TD; Cinner JE; Green A; Pressey RL

2013-06-01

130

Exposure assessment for trace elements from consumption of marine fish in Southeast Asia  

Energy Technology Data Exchange (ETDEWEB)

Concentrations of 20 trace elements were determined in muscle and liver of 34 species of marine fish collected from coastal areas of Cambodia, Indonesia, Malaysia and Thailand. Large regional difference was observed in the levels of trace elements in liver of one fish family (Carangidae): the highest mean concentration was observed in fish from the Malaysian coastal waters for V, Cr, Zn, Pb and Bi and those from the Java Sea side of Indonesia for Sn and Hg. To assess the health risk to the Southeast Asian populations from consumption of fish, intake rates of trace elements were estimated. Some marine fish showed Hg levels higher than the guideline values by U.S. Environmental Protection Agency and Joint FAO/WHO Expert Committee on Food Additives (JECFA). This suggests that consumption of these fish may be hazardous to the people. -- Intake of mercury through consumption of some marine fish species might be hazardous to the people in Southeast Asia.

Agusa, Tetsuro [Center for Marine Environmental Studies (CMES), Ehime University, Bunkyo-cho 2-5, Matsuyama 790-8577 (Japan); Kunito, Takashi [Department of Environmental Sciences, Faculty of Science, Shinshu University, 3-1-1 Asahi, Matsumoto 390-8621 (Japan); Sudaryanto, Agus [Center for Marine Environmental Studies (CMES), Ehime University, Bunkyo-cho 2-5, Matsuyama 790-8577 (Japan); Monirith, In [Center for Marine Environmental Studies (CMES), Ehime University, Bunkyo-cho 2-5, Matsuyama 790-8577 (Japan); Kan-Atireklap, Supawat [Center for Marine Environmental Studies (CMES), Ehime University, Bunkyo-cho 2-5, Matsuyama 790-8577 (Japan); Iwata, Hisato [Center for Marine Environmental Studies (CMES), Ehime University, Bunkyo-cho 2-5, Matsuyama 790-8577 (Japan); Ismail, Ahmad [Department of Biology, Faculty of Science and Environmental Studies, Universiti Putra Malaysia, 43400 Serdang, Selangor (Malaysia); Sanguansin, Joompol [Eastern Marine Fisheries Development Center, Ban Phe, Muang, Rayong 21160 (Thailand); Muchtar, Muswerry [Research and Development Center for Oceanology Indonesia Institute of Sciences, Jl. Pasir Putih 1, Ancol Timur, Jakarta 11048 (Indonesia); Tana, Touch Seang [Social and Cultural Observation Unit (OBSES), Office of the Council of Ministers, Phnom Penh (Cambodia); Tanabe, Shinsuke [Center for Marine Environmental Studies (CMES), Ehime University, Bunkyo-cho 2-5, Matsuyama 790-8577 (Japan)]. E-mail: shinsuke@agr.ehime-u.ac.jp

2007-02-15

131

Preliminary assessment of surf-zone and estuarine line-fish species of the Dwesa-Cwebe Marine Protected Area, Eastern Cape, South Africa  

Directory of Open Access Journals (Sweden)

Full Text Available A preliminary assessment of surf-zone and estuarine line fish was carried out in the DwesaCwebe Marine Protected Area (MPA), on the Wild Coast, South Africa. The purpose was to provide baseline data on inshore line-fish stocks in the MPA. A total of 28 species was recorded, of which 53% have a conservation status reflecting some concern and 43% are endemic to southern Africa. This highlights the value of the MPA for protection of important line-fish species. Within the MPA, localised differences were detected in species diversity, size frequency and catch per unit effort between unexploited and illegally exploited areas. These differences were more prominent in slow growing, long-lived species. It thus appears that illegal exploitation is negatively affecting fish populations within the MPA, which counteract and potentially could eliminate the benefits of fish protection typically associated with no-take MPAs. These results highlight the need for improved law enforcement and better communication with neighbouring communities to increase awareness. It is further recommended that the current no-take status of the MPA should be maintained. In addition, baseline fisheries information was collected on certain fish species that could be used to inform future conservation management of the MPA.Conservation implications: The Dwesa-Cwebe Marine Protected Area is unique and important for the conservation of key surf zone and estuarine fish species. However there is a significant risk to the fish populations due to illegal exploitation. Key interventions should include enhanced law enforcement but, more important, the creation of alternative livelihoods and long term sustainable benefits to local communities.

Jan A. Venter; Bruce Q. Mann

2012-01-01

132

Preliminary assessment of surf-zone and estuarine line-fish species of the Dwesa-Cwebe Marine Protected Area, Eastern Cape, South Africa  

Scientific Electronic Library Online (English)

Full Text Available Abstract in english A preliminary assessment of surf-zone and estuarine line fish was carried out in the Dwesa-Cwebe Marine Protected Area (MPA), on the Wild Coast, South Africa. The purpose was to provide baseline data on inshore line-fish stocks in the MPA. A total of 28 species was recorded, of which 53% have a conservation status reflecting some concern and 43% are endemic to southern Africa. This highlights the value of the MPA for protection of important line-fish species. Within the M (more) PA, localised differences were detected in species diversity, size frequency and catch per unit effort between unexploited and illegally exploited areas. These differences were more prominent in slow growing, long-lived species. It thus appears that illegal exploitation is negatively affecting fish populations within the MPA, which counteract and potentially could eliminate the benefits of fish protection typically associated with no-take MPAs. These results highlight the need for improved law enforcement and better communication with neighbouring communities to increase awareness. It is further recommended that the current no-take status of the MPA should be maintained. In addition, baseline fisheries information was collected on certain fish species that could be used to inform future conservation management of the MPA. CONSERVATION IMPLICATIONS: The Dwesa-Cwebe Marine Protected Area is unique and important for the conservation of key surf zone and estuarine fish species. However there is a significant risk to the fish populations due to illegal exploitation. Key interventions should include enhanced law enforcement but, more important, the creation of alternative livelihoods and long term sustainable benefits to local communities.

Venter, J.A.; Mann, B.Q.

2012-01-01

133

Regulatory impact assessment : future of UK's system for holding stocks of oil for use in the event of disruption  

International Nuclear Information System (INIS)

[en] This consultation document focuses on the adaption of the United Kingdom government's system for holding emergency stocks of oil to ensure the compliance with international obligations and security of energy supply objectives. The background to the study is traced, and the rational for government intervention is discussed along with the current system which bases obligations on company sales into final consumption, and the urgent need for a new system. Consultation within government resulting in agreement that the system should continue to be based on company obligations and public consultations are discussed. Potential options are assessed and problems with continuing with the existing system based on company obligations are highlighted

2007-01-01

134

Assessing carbon stocks and modelling win-win scenarios of carbon sequestration through land-use changes  

Energy Technology Data Exchange (ETDEWEB)

This publication presents a methodology and software tools for assessing carbon stocks and modelling scenarios of carbon sequestration that were developed and tested in pilot field studies in Mexico and Cuba. The models and tools enable the analysis of land use change scenarios in order to identify in a given area (watershed or district) land use alternatives and land management practices that simultaneously maximize food production, maximize soil carbon sequestration, maximize biodiversity conservation and minimize land degradation. The objective is to develop and implement 'win-win' options that satisfy the multiple goals of farmers, land users and other stakeholders in relation to food security, carbon sequestration, biodiversity and land conservation.

Ponce-Hernandez, R.; Koohafkan, P.; Antoine, J. (eds.)

2004-07-01

135

Assessment of the relationship between oil prices and US oil stocks  

International Nuclear Information System (INIS)

This paper qualitatively and quantitatively analyzes the relationship between US monthly ending oil stocks position with that of West Texas Intermediate (WTI) oil prices from February 1995 to July 2004. The paper concludes if other things are held constant, WTI is inversely related to the petroleum products (PPP), combined petroleum products and crude oil (CPPP), crude oil alone (Crude), total oil stocks including petroleum products, crude oil and strategic petroleum reserves SPR (Total), total gasoline (TGO), total distillate (TDO). It could not establish a statistically significant and negative relationship with SPR when run alone. One percent increase (decrease) in CPPP, PPP, Crude, Total, TGO and TDO leads to decrease (increase) in WTI, respectively, by 0.70, 0.43, 0.37, 0.97, 0.26 and 0.21 percent. Oil prices are largely influenced by total crude and Crude and PPP inventories levels while modestly with variations in gasoline and distillate stocks levels. Despite a healthy increase of over 22 percent in SPR from January 2001 to April 2004, it did not result in easing of oil prices. Primarily because SPR are meant for security of supply concern and are only released under extreme conditions by the President of United States, they are neither meant for the purposes of balancing supply-demand gap nor for the stability of oil prices. The aggressive SPR buildup in recent years is related to international terrorism, geopolitical situation in the Middle East, particularly in Iraq, that encourages US government to enhance its SPR to meet any short-term eventuality. The analyst must keep a close eye on CPPP and the total oil stocks variation to forecast WTI in the short run whilst gasoline and distillate influence oil prices modestly in the short run. SPR, on the other hand, are expected to play a pivotal role in balancing oil prices and in providing a critical resource for the economy in case of any major shortfall in the long run.

1995-02-00

136

Histological methods in the assessment of different feed effects on liver and intestine of fish  

Directory of Open Access Journals (Sweden)

Full Text Available This manuscript describes the importance of using histological methods to assess the effects of feed on the liver and intestine of fish. Due to the constantly increasing world production of fish and other aquatic organisms, it is necessary to replace fishmeal and fish oil in diets with less expensive raw materials of plant origin. Due to the increased fiber content, increased presence of carbohydrates, antinutritional factors, and inappropriate content of amino acids and new compounds can have negative effects on the digestive system of fish and therefore on fitness, health and production characteristics of cultivated fish. The liver and intestines are the most important organs for the digestion and absorption of nutrients from feed. Therefore, monitoring histological structure of fish liver and intestine is the method of choice in assessing the effects of nutrient mixtures that use raw materials of plant origin. For both of these vital organs the normal histological structure and the most important results obtained by research are discussed. This paper presents a critical review of the histological methods used in research on feed effects. Results related to the negative effects of raw soy-based feed on the occurrence of enteritis in carnivorous fish species are discussed. The results point out that use of modern approach in fish pathology such as improved histochemical, stereological, scoring, and other analytical methods could be a beneficial approach in an accurate assessment of new feed effects on fish.

Raškovi? Božidar S.; Stankovi? Marko B.; Markovi? Zoran Z.; Poleksi? Vesna D.

2011-01-01

137

An assessment of fish mortality at the Rance tidal power barrage, Brittany, France  

International Nuclear Information System (INIS)

This report describes the results of three weeks field work carried out on the Rance Estuary in August 1991. The objectives were to make a preliminary assessment of the relative frequency with which dead fish accumulate in the Rance barrage lock pit; to assess the likely cause of mortality; and to assess the success with which marine fish migrate across a tidal barrage by tagging a variety of species within the barrage basin. (author).

1992-01-01

138

An assessment of fish mortality at the Rance tidal power barrage, Brittany, France  

Energy Technology Data Exchange (ETDEWEB)

This report describes the results of three weeks field work carried out on the Rance Estuary in August 1991. The objectives were to make a preliminary assessment of the relative frequency with which dead fish accumulate in the Rance barrage lock pit; to assess the likely cause of mortality; and to assess the success with which marine fish migrate across a tidal barrage by tagging a variety of species within the barrage basin. (author).

Lockwood, S.J.; Baynes, S.M.

1992-12-31

139

Final Environmental Assessment: Rifle Creek Fish Screen Project.  

Science.gov (United States)

The Colorado Division of Wildlife (CDOW) is proposing to construct and operate a fish screen in Rifle Creek to prevent or minimize non-native fish from Rifle Gap Reservoir from entering the downstream Colorado River via Rifle Creek. The Bureau of Reclamat...

2011-01-01

140

Co-assessment of biomass and soil organic carbon stocks in a future reservoir area located in Southeast Asia.  

UK PubMed Central (United Kingdom)

An assessment of the organic carbon stock present in living or dead vegetation and in the soil on the 450 km2 of the future Nam Theun 2 hydroelectric reservoir in Lao People's Democratic Republic was made. Nine land cover types were defined on the studied area: dense, medium, light, degraded, and riparian forests; agricultural soil; swamps; water; and others (roads, construction sites, and so on). Their geographical distribution was assessed by remote sensing using two 2008 SPOT 5 images. The area is mainly covered by dense and light forests (59%), while agricultural soil and swamps account for 11% and 2%, respectively. For each of these cover types, except water, organic carbon density was measured in the five pools defined by the Intergovernmental Panel on Climate Change: aboveground biomass, litter, deadwood, belowground biomass, and soil organic carbon. The area-weighted mean carbon densities for these pools were estimated at 45.4, 2.0, 2.2, 3.4, and 62.2 tC/ha, respectively, i.e., a total of about 115±15 tC/ha for a soil thickness of 30 cm, corresponding to a total flooded organic carbon stock of 5.1±0.7 MtC. This value is much lower than the carbon density for some South American reservoirs for example where total organic carbon stocks range from 251 to 326 tC/ha. It can be mainly explained by (1) the higher biomass density of South American tropical primary rainforest than of forests in this study and (2) the high proportion of areas with low carbon density, such as agricultural or slash-and-burn zones, in the studied area.

Descloux S; Chanudet V; Poilvé H; Grégoire A

2011-02-01

 
 
 
 
141

Oil stocks  

Energy Technology Data Exchange (ETDEWEB)

This paper focuses on the need for the oil industry to hold stocks and the relationship between stocks and future prices. The role of future markets is explored, and the influence of public inventories on private oil stocks, and the just-in-time inventory management practices are considered. (UK)

Long, D.; Verleger, P. [Charles River Associates, Inc., Washington, DC (United States); Okugu, B. [OPEC, Vienna (Austria); Cantor, B.; Waguespeck, K. [Andersen (Arthur),Associates, Houston, TX (United States)

1996-11-01

142

Environmental assessment, K Pool fish rearing, Hanford Site, Richland, Washington  

International Nuclear Information System (INIS)

[en] The US Department of Energy (DOE) has a need to respond to a request to lease facilities at the Hanford Site 100-KE and 100-KW filter plant pools (K Pools) for fish rearing activities. These fish rearing activities would be: (1) business ventures with public and private funds and (2) long-term enhancement and supplementation programs for game fish populations in the Columbia River Basin. The proposed action is to enter into a use permit or lease agreement with the YIN or other parties who would rear fish in the 100-K Area Pools. The proposed action would include necessary piping, pump, and electrical upgrades of the facility; cleaning and preparation of the pools; water withdrawal from the Columbia River, and any necessary water or wastewater treatment; and introduction, rearing and release of fish. Future commercial operations may be included

1996-01-01

143

Environmental assessment, K Pool fish rearing, Hanford Site, Richland, Washington  

Energy Technology Data Exchange (ETDEWEB)

The US Department of Energy (DOE) has a need to respond to a request to lease facilities at the Hanford Site 100-KE and 100-KW filter plant pools (K Pools) for fish rearing activities. These fish rearing activities would be: (1) business ventures with public and private funds and (2) long-term enhancement and supplementation programs for game fish populations in the Columbia River Basin. The proposed action is to enter into a use permit or lease agreement with the YIN or other parties who would rear fish in the 100-K Area Pools. The proposed action would include necessary piping, pump, and electrical upgrades of the facility; cleaning and preparation of the pools; water withdrawal from the Columbia River, and any necessary water or wastewater treatment; and introduction, rearing and release of fish. Future commercial operations may be included.

NONE

1996-12-01

144

Fish Alternatives in Environmental Risk Assessment: Overview of the Current Landscape  

Science.gov (United States)

The need for alternative testing strategies has recently expanded into the realm of environmental risk assessment leading to the development of new alternatives to standard aquatic vertebrate testing such as the OECD 203 acute fish toxicity test. The fish embryo test (FET) is one...

145

[Hydroacoustic assessment of fish resources in reservoirs with different fishery management].  

UK PubMed Central (United Kingdom)

By using Biosonics DT-X echosounder (208 kHz), a hydroacoustic investigation was conducted on the fish resources in three mesotrophic reservoirs (Daxi Reservoir, Shahe Reservoir, and Jinniushan Reservoir) with different fishery management in late autumn and early winter 2011, and a GIS model was constructed to assess the fish resource distribution in the reservoirs. No significant difference was observed in the average size of fish in the three reservoirs, but the distribution curves of fish target strength (TS) showed that the fish size distribution proportion was different, and had close correlation with fishery management. The fish density in Daxi Reservoir (averagely 0.0183 ind x m(-3)) had no significant difference with that in Shahe Reservoir (averagely 0.0124 ind x m(-3)), but the fish density in Jinniushan Reservoir (averagely 0.0085 ind x m(-3)) was significantly lower than that in Daxi and Shahe reservoirs. There was no significant correlation between the horizontal distribution of fish density and the water depth in the three reservoirs. The fish in the three reservoirs were in group distribution, and fish aggregation was found in Daxi and Shahe reservoirs. In the three reservoirs, the fish biomass was the highest in downstream, and there was a greater biomass near the dam, except in Shahe Reservoir which was affected by fish catch activity. Based on the raster data obtained from GIS fish distribution model and the surface water area of each grid, the total amount of fish resources with the TS > -60 dB in the Daxi, Shahe and Jinniushan reservoirs was estimated as about 480000, 610000 and 520000 individuals, and that with the TS > -40 dB was about 50400, 52900 and 90700 individuals, respectively.

Sun MB; Gu XH; Zeng QF; Mao ZG; Gu XK

2013-01-01

146

A new technique for assessing fish passage survival at hydro power stations  

International Nuclear Information System (INIS)

[en] The HI-Z Turb'N Tag recovery method is presented as a new technique that has been successfully used at ten hydropower stations to determine turbine or spillway passage survival of fish. According to this technique, fish are tagged with the Turb'N Tag, which is pear-shaped, made of inflatable latex, and ca 35 mm long and 13 mm wide. The tag is designed to inflate after passage through the turbine, where it then floats the fish to the surface where it can be easily spotted and netted. One tag is sufficient to retrieve fish less than 18 cm long, while three tags may be needed for fish longer than 30 cm. In tests, fish were recovered in under 10 minutes from the tailrace after being tagged and released into a turbine. The tag allowed over 90% recovery of fish in most tests. The technique had minimal effect on the well-being of both hardy and sensitive species and provided an opportunity to examine recovered fish for injuries and retain them up to 72 h to assess possible delayed effects. The technique overcomes most of the logistical problems associated with conventional methods (netting, radio telemetry, mass mark-recapture) to determine turbine passage survival. The technique can also be used to assess effects of spill and fish bypass structures. 9 refs., 2 figs., 1 tab

1993-01-01

147

Genotoxicity Assessment of Mercuric Chloride in the Marine Fish Therapon jaruba.  

Directory of Open Access Journals (Sweden)

Full Text Available The aim of the present study was to standardize and to assess the predictive value of the cytogenetic analysis by Micronucleus (MN) test in fish erythrocytes as a biomarker for marine environmental contamination. Micronucleus frequency baseline in erythrocytes was evaluated in and genotoxic potential of a common chemical was determined in fish experimentally exposed in aquarium under controlled conditions. Fish (Therapon jaruba) were exposed for 96 h to a single heavy metal (mercuric chloride). Chromosomal damage was determined as micronuclei frequency in fish erythrocytes. Significant increase in MN frequency was observed in erythrocytes of fish exposed to mercuric chloride. Concentration of 0.25 ppm induced the highest MN frequency (2.95 micronucleated cells/1000 cells compared to 1 MNcell/1000 cells in control animals). The study revealed that micronucleus test, as an index of cumulative exposure, appears to be a sensitive model to evaluate genotoxic compounds in fish under controlled conditions.

Nagarajan Nagarani

2009-01-01

148

Assessment of fish passage technology applicable to John Sevier detention dam  

Energy Technology Data Exchange (ETDEWEB)

This report provides an assessment of existing technologies and developments in fish passage technology applicable to moving sauger and paddlefish upstream and downstream of the John Sevier detention dam. (ACR)

Pasch, R.W.

1986-12-01

149

Challenge of Assessing Climate Change Effects on Fish and Wildlife Resources in the Western United States.  

Science.gov (United States)

This paper presents a preliminary assessment of the sensitivity of western US fish and wildlife habitats and representative species to various scenarios of change. Output from global climate change models and professional judgement of environmental scient...

R. P. Breckenridge M. D. Otis R. C. Rope J. G. Cornish R. E. Trout

1988-01-01

150

Challenges in using fish communities for assessing the ecological integrity of non-perennial rivers  

Scientific Electronic Library Online (English)

Full Text Available Abstract in english Environmental Water Assessments (EWAs) aim to protect the ecological integrity of rivers amidst increasing anthropogenic pressures on freshwater resources, and fish communities are the ecosystem component most commonly included. The Fish Response Assessment Index (FRAI) was developed to assess the integrity of fish communities in South African rivers and is commonly applied in EWA studies. This paper reports on the suitability of the FRAI for the non-perennial Seekoei Riv (more) er and discusses some of the challenges faced. Our relatively long and thorough study on the Seekoei River confirmed the concerns that earlier, snapshot, fish integrity assessments in the Orange River system raised: that the existing fish indices are not ideally suited for these rivers with their naturally low species richness and hardy, generalist fish communities. Other difficulties with the use of a score-based method include prediction of the expected species, calculation of a frequency of occurrence rating, selection of the right sampling times for comparative purposes, loss of habitats and sampling points under different flow conditions, and problems experienced when using accumulated data to try to correct for a situation of having too few sampling points. At this stage a more generalised approach is suggested for the Seekoei River, and ultimately other similar non-perennial systems. This could include a number of community characteristics, such as abundance, species richness, species diversity and evenness, recruitment, fish health and the presence/absence of exotic species.

Avenant, MF

2010-07-01

151

Climate change vulnerability of native and alien freshwater fishes of California: a systematic assessment approach.  

UK PubMed Central (United Kingdom)

Freshwater fishes are highly vulnerable to human-caused climate change. Because quantitative data on status and trends are unavailable for most fish species, a systematic assessment approach that incorporates expert knowledge was developed to determine status and future vulnerability to climate change of freshwater fishes in California, USA. The method uses expert knowledge, supported by literature reviews of status and biology of the fishes, to score ten metrics for both (1) current status of each species (baseline vulnerability to extinction) and (2) likely future impacts of climate change (vulnerability to extinction). Baseline and climate change vulnerability scores were derived for 121 native and 43 alien fish species. The two scores were highly correlated and were concordant among different scorers. Native species had both greater baseline and greater climate change vulnerability than did alien species. Fifty percent of California's native fish fauna was assessed as having critical or high baseline vulnerability to extinction whereas all alien species were classified as being less or least vulnerable. For vulnerability to climate change, 82% of native species were classified as highly vulnerable, compared with only 19% for aliens. Predicted climate change effects on freshwater environments will dramatically change the fish fauna of California. Most native fishes will suffer population declines and become more restricted in their distributions; some will likely be driven to extinction. Fishes requiring cold water (<22°C) are particularly likely to go extinct. In contrast, most alien fishes will thrive, with some species increasing in abundance and range. However, a few alien species will likewise be negatively affected through loss of aquatic habitats during severe droughts and physiologically stressful conditions present in most waterways during summer. Our method has high utility for predicting vulnerability to climate change of diverse fish species. It should be useful for setting conservation priorities in many different regions.

Moyle PB; Kiernan JD; Crain PK; Quiñones RM

2013-01-01

152

Climate Change Vulnerability of Native and Alien Freshwater Fishes of California: A Systematic Assessment Approach  

Science.gov (United States)

Freshwater fishes are highly vulnerable to human-caused climate change. Because quantitative data on status and trends are unavailable for most fish species, a systematic assessment approach that incorporates expert knowledge was developed to determine status and future vulnerability to climate change of freshwater fishes in California, USA. The method uses expert knowledge, supported by literature reviews of status and biology of the fishes, to score ten metrics for both (1) current status of each species (baseline vulnerability to extinction) and (2) likely future impacts of climate change (vulnerability to extinction). Baseline and climate change vulnerability scores were derived for 121 native and 43 alien fish species. The two scores were highly correlated and were concordant among different scorers. Native species had both greater baseline and greater climate change vulnerability than did alien species. Fifty percent of California’s native fish fauna was assessed as having critical or high baseline vulnerability to extinction whereas all alien species were classified as being less or least vulnerable. For vulnerability to climate change, 82% of native species were classified as highly vulnerable, compared with only 19% for aliens. Predicted climate change effects on freshwater environments will dramatically change the fish fauna of California. Most native fishes will suffer population declines and become more restricted in their distributions; some will likely be driven to extinction. Fishes requiring cold water (<22°C) are particularly likely to go extinct. In contrast, most alien fishes will thrive, with some species increasing in abundance and range. However, a few alien species will likewise be negatively affected through loss of aquatic habitats during severe droughts and physiologically stressful conditions present in most waterways during summer. Our method has high utility for predicting vulnerability to climate change of diverse fish species. It should be useful for setting conservation priorities in many different regions.

Moyle, Peter B.; Kiernan, Joseph D.; Crain, Patrick K.; Quinones, Rebecca M.

2013-01-01

153

Climate change vulnerability of native and alien freshwater fishes of California: a systematic assessment approach.  

Science.gov (United States)

Freshwater fishes are highly vulnerable to human-caused climate change. Because quantitative data on status and trends are unavailable for most fish species, a systematic assessment approach that incorporates expert knowledge was developed to determine status and future vulnerability to climate change of freshwater fishes in California, USA. The method uses expert knowledge, supported by literature reviews of status and biology of the fishes, to score ten metrics for both (1) current status of each species (baseline vulnerability to extinction) and (2) likely future impacts of climate change (vulnerability to extinction). Baseline and climate change vulnerability scores were derived for 121 native and 43 alien fish species. The two scores were highly correlated and were concordant among different scorers. Native species had both greater baseline and greater climate change vulnerability than did alien species. Fifty percent of California's native fish fauna was assessed as having critical or high baseline vulnerability to extinction whereas all alien species were classified as being less or least vulnerable. For vulnerability to climate change, 82% of native species were classified as highly vulnerable, compared with only 19% for aliens. Predicted climate change effects on freshwater environments will dramatically change the fish fauna of California. Most native fishes will suffer population declines and become more restricted in their distributions; some will likely be driven to extinction. Fishes requiring cold water (alien fishes will thrive, with some species increasing in abundance and range. However, a few alien species will likewise be negatively affected through loss of aquatic habitats during severe droughts and physiologically stressful conditions present in most waterways during summer. Our method has high utility for predicting vulnerability to climate change of diverse fish species. It should be useful for setting conservation priorities in many different regions. PMID:23717503

Moyle, Peter B; Kiernan, Joseph D; Crain, Patrick K; Quiñones, Rebecca M

2013-05-22

154

The Assessment of Social Reporting on behalf of Accepted Corporations Listed in Tehran Stock Exchange  

Directory of Open Access Journals (Sweden)

Full Text Available During the recent years that many changes have accomplished in economy and social expectations, typically the accounting world has confronted the society with the socio-environmental effects of industries development. According to these changes in society and environment, accounting also affects from it s environment. In this study the feasibility of social reporting on behalf of accepted corporations listed in Tehran stock exchange has been studied. In this survey we accumulate required data about corporations using a questionnaire and due to the obviousness of statistical population size to estimate the sample size. Conclusions of research indicate that factors such as lack of appropriate accounting information system, lack of awareness of managers about the social cost and nonexistence of legal standards and high social reporting costs causes the avoidance of social reporting on behalf of Iranian corporations.

Hosseyn Karbasi Yazdi; Kobra Hemmati; Ali Bayat

2012-01-01

155

Open-grown crown radius of eleven bottomland hardwood species: Prediction and use in assessing stocking  

Energy Technology Data Exchange (ETDEWEB)

Equations were prepared to predict crown radius for eleven species of open-grown bottomland hardwood trees. Crown radius was predicted as a function of diameter at breast height (dbh) and as a function of dbh, total height, and crown ratio. Equations were prepared for individual species and species groups. Pecan has the largest crowns over a broad range of dbh. Eastern cottonwood has the smallest crowns for most levels of dbh. Sweetgum has relatively small crowns for trees of small dbh, but crown radius is comparable to most species at the largest dbh. The crown radius predictions may be used to calculate crown competition factor. B-lines of stocking may be calculated that represent a stand of one species as well as a mixed-species stand of any particular species proportion.

Goelz, J.C.G.

1996-08-01

156

Assessing the risk of alternative management strategies in a Mediterranean fishery: protecting the younger vs reducing fishing effort.  

Science.gov (United States)

A stochastic age-structured population model was developed to explore biologically favourable levels of effort and closing periods within the sardine pelagic fishery in the eastern Mediterranean Sea. Results suggested that the developed age-structured model captured the observed biomass fluctuations and catches reasonably well and represents the first comprehensive investigation of alternative management strategies for eastern Mediterranean sardine fishery that include stochasticity. The present study provided direct evidence for the importance of the correct timing of the temporal fishing ban. Significant benefits were found both in terms of biomass and catch from a corrective shift in the fishing closed period. The current findings suggested that protecting the younger age groups from fishing in the period October-December, by shifting the ban period earlier than December may profit, biologically, the stock and economically the fishing sector. Progressive reductions in fishing mortality/effort also yield significant positive biological and fishery benefits in the short term. PMID:23931664

Politikos, D V; Maravelias, C D; Tzanetis, D E

2013-01-01

157

Assessing the risk of alternative management strategies in a Mediterranean fishery: protecting the younger vs reducing fishing effort.  

UK PubMed Central (United Kingdom)

A stochastic age-structured population model was developed to explore biologically favourable levels of effort and closing periods within the sardine pelagic fishery in the eastern Mediterranean Sea. Results suggested that the developed age-structured model captured the observed biomass fluctuations and catches reasonably well and represents the first comprehensive investigation of alternative management strategies for eastern Mediterranean sardine fishery that include stochasticity. The present study provided direct evidence for the importance of the correct timing of the temporal fishing ban. Significant benefits were found both in terms of biomass and catch from a corrective shift in the fishing closed period. The current findings suggested that protecting the younger age groups from fishing in the period October-December, by shifting the ban period earlier than December may profit, biologically, the stock and economically the fishing sector. Progressive reductions in fishing mortality/effort also yield significant positive biological and fishery benefits in the short term.

Politikos DV; Maravelias CD; Tzanetis DE

2013-01-01

158

Spatial interpolation of in situ data by self-organizing map algorithms (neural networks) for the assessment of carbon stocks in European forests  

UK PubMed Central (United Kingdom)

Self-organizing maps (SOMs) are an advanced neural networks application. SOMs were applied for the spatially explicit estimation of forest carbon stocks for a test region in Thuringia (Germany). The approach utilizes in situ national forest inventory data and satellite remote sensing data (Landsat 7 ETM+) and provides maps showing a high-resolution spatial distribution of forest carbon stocks. The generated maps are compared to alternative estimates obtained by the k-nearest neighbour (kNN) method—a remote sensing based carbon assessment. Beside maps the SOM- and kNN-approaches were utilized to calculate statistical estimates of carbon stock and growing stock. The statistical estimates were validated by calculating bias and mean square errors with reference to in situ assessments. SOM- and kNN-approaches have been tested in a forested region in Central Germany. The results show that SOMs are an approach that has the ability to reproduce the spatial pattern of forest carbon stocks. SOMs are—with some restrictions—comparable to spatially explicit estimates generated by the kNN-method.

Stümer Wolfgang; Kenter Bernhard; Köhl Michael

2010-06-01

159

Closed recirculating culture of scorpaenid fish and puffer fish. Examination of nitrogen-excretion rate, proper stocking density and optimum temperature, and rearing experiments; Junkan roka hoshiki ni yoru oniokoze oyobi torafugu yogyo gijutsu no kaihatsu. Chisso haishutsuryo, tekisei shuyo mitsudo, koteki suion no kaimei oyobi shiiku shiken  

Energy Technology Data Exchange (ETDEWEB)

Nitrogen excretion rate, proper stocking density, and optimum temperature for growth were examined on scorpaenid fish and puffer fish to establish closed recirculating culture techniques. Nitrogen excretion rate of scorpaenid fish about 5, 10 and 150 g in body weight was 20, 28 and 10 mg-N/100 g/day after feeding, respectively. Necessary volume of net filter medium to produce 1 kg of fish was estimated to be 1 liter. Growth rate and survival rate of fish were not affected by rearing density of 10 to 30 kg/m{sup 2}-bottom area of cage. The optimum temperature for the growth was 27degC regardless of development stage. Nitrogen excretion rate of puffer fish about 23 g in body weight was 60 mg-N/100 g/day after feeding. Necessary volume of net filter medium to produce 1 kg of fish was estimated to be 2 liters. Growth rate of fish was not affected by rearing density of 6 to 50 kg/m{sup 3}-volume of cage. However, a survival rate was slightly decreased as the rearing density increased. For the fish of 3 g in body weight, growth at 18degC was significantly inferior to those at 21, 24 and 27degC. For the fish of 54 g, growth at 25degC was superior to those at 15, 20 and 30degC. Survival rate of both sizes of fish was decreased as the temperature increased. 59 refs., 9 figs., 9 tabs.

Furuta, T.; Kikuchi, K.; Iwata, N.; Honda, H. [Central Research Institute of Electric Power Industry, Tokyo (Japan)

1997-03-01

160

An evaluation of multi-annual management strategies for ICES roundfish stocks  

DEFF Research Database (Denmark)

Current scientific management objectives for ICES roundfish stocks are to ensure conservation of the biological resource and do not explicitly consider economic or social objectives. For example, there are currently no objectives to maximize the sustainable yield or to reduce variability in total allowable catches (TACs). This is despite the fact that the current system can result in wide annual fluctuations in TAC, limiting the ability of the fishing industry to plan for the future. Therefore, this study evaluated management strategies that stabilized catches by setting bounds on the interannual variability in TACs. An integrated modelling framework was used, which simulated both the real and observed systems and the interactions between system components. This allowed the evaluation of candidate management strategies with respect to the intrinsic properties of the systems, as well as our ability to observe, monitor, assess, and control them. Strategies were evaluated in terms of risk (measured as the probability of spawning-stock biomass falling below a biomass threshold for the stock) and cumulative yield. In general, bounds on interannual TAC change of 10% and 20% affected the ability to achieve management targets, although the outcome of applying TAC bounds could not have been pre-judged because results were highly dependent on the specific biology of the stock, current status, and the interaction with assessment and management. For example, for North Sea haddock, management became less responsive to fluctuations resulting from large recruitment events. Simulated target fishing mortality levels were rarely achieved, regardless of the TAC bound applied, and actual fishing mortality rates oscillated around the target. In the longer term, more restrictive bounds resulted in oscillations of greater amplitude and wavelength in yield and SSB. Bounds had less effect when a stock was close to the biomass corresponding to the target F. Risk for stocks that are declining or currently at low abundance may be greater, because if bounds restrict the extent to which TACs can be reduced each year, they could lead to collapse of the stock and the loss of all future revenue. However, for a recovered stock or one at high abundance, the loss of yield as a result of bounds would be smaller than that caused by the total collapse of the fishery. At low stock size or if the stock was declining, catches should be changed more rapidly than when the stock was increasing or at a high level, especially high stock sizes acting as an insurance against uncertainty. Therefore, rebuilding strategies, and strategies aimed at maintaining the stock above prescribed limits, should be considered separately. (c) 2005 International Council for the Exploration of the Sea. Published by Elsevier Ltd. All rights reserved.

Kell, L.T.; Pilling, G.M.

2006-01-01

 
 
 
 
161

Stream fishes and desirable fish stocks  

DEFF Research Database (Denmark)

Freshwater fi sh communities have always been valuable resources for society, particularly the species that migrate between freshwater and the sea. Historically, eel, salmon and trout were so abundant that good fi shing luck could turn a capable fi sherman into a wealthy person. Unfortunately, migrating fi sh became threatened by over-fi shing quite early in human history. The more recent construction of dams and other habitat destruction associated with development of towns, industries and intensive agriculture have reduced populations further. The largest Danish river, the River Gudenå, illustrates this historical decline and also the diffi culty of re-establishing healthy fi sh communities once the original populations have deteriorated or, in the case of salmon, become extinct. Efforts are currently needed to be made to effectively restore and manage fi sh communities in streams.

Dieperink, C.; Sand-Jensen, K.

2006-01-01

162

Survey and evaluation of instream habitat and stock restoration techniques for wild pink and chum salmon. Restoration study number 105-1 (restoration project 93063). Exxon Valdez oil spill state/federal natural resource damage assessment final report  

Energy Technology Data Exchange (ETDEWEB)

This project is the result of a three-year survey of the Exxon Valdez oil spill impact area to identify appropriate and cost-effective instream habitat restoration techniques for salmon, including spawning channels and improvement of fish passage through fish ladders or step-pool structures to overcome physical or hydrological barriers. Additional wild salmon stock rehabilitation measures include stream-side incubation boxes, remote egg-taking, incubation at existing hatcheries for fry stocking in oil-impacted streams, and fry rearing. Study results include the identification of the most promising instream habitat restoration projects in each of the spill-impacted areas.

Willette, T.M.; Dudiak, N.C.; Honnold, S.G.; Carpenter, G.; Dickson, M.

1995-08-01

163

Carbon stock assessment of three selected agroforestry systems in Bukidnon, Philippines  

Directory of Open Access Journals (Sweden)

Full Text Available Climate change, caused by global warming, is a phenomenon partly resulting from abundance of carbon dioxide in the atmosphere.It is the most pressing environmental problem of the world today. It persists, and it cannot be stopped. Rather, it can be mitigated. Agroforestrysystems as land use can reduce the atmospheric concentration of carbon dioxide. This study therefore aimed to generate data on the carbonstocks of three selected agroforestry systems located within the Province of Bukidnon. The methodologies used include measurement of treesat diameter breast height (dbh) and sampling of herbaceous vegetation, litter, and soil for carbon content determination and farmer interview.Results showed that carbon accumulation of agroforestry systems goes along with the following order: taungya agroforestry system (174 MgCha-1) > mixed multistorey system (162 MgC ha-1) > falcata-coffee multistorey system (92 MgC ha-1). Carbon was stored in the various pools inthe following order of magnitude: soil (77-92%) > trees (7-22%) > herbaceous vegetation and litter (1%). Compared with natural forests, theseselected agroforestry systems represents 23-44% of the total carbon stock. Policy programs promoting the establishment of agroforestry systemsin idle lands in Bukidnon should be considered.

Mildred M. Labata; Edgardo C. Aranico; Alicia Catalina E. Tabaranza; Jose Hermis P. Patricio; Ruben F. Amparado, Jr

2012-01-01

164

Carbon stock assessment of two agroforestry systems in a tropical forest reserve in the Philippines  

Energy Technology Data Exchange (ETDEWEB)

Carbon dioxide is the most abundant greenhouse gas (GHG) that causes global warming. Thus, land uses such as an agroforestry system have a significant role in moderating climate change since they can be sources and sinks of carbon. The aim of the study was to generate data on the carbon stocks of two agroforestry systems, specifically a Gmelina arborea-Theobroma cacao multistorey system and an alley cropping system with Gliricidia sepium hedges at the agroforestry research and demonstration area inside a forest reserve in Southern Luzon, Philippines. The multistorey system had a mean biomass of 258 Mg C ha{sup -1} and a carbon density of 185 Mg C ha{sup -1}. Carbon was stored in the various pools in the following order of magnitude: soil > tree biomass (above-ground) > necromass > understorey vegetation > roots. The Gliricidia hedgerow had a biomass density of 3.8 Mg C ha{sup -1}; total carbon density was 93 Mg C ha{sup -1}, of which 92 Mg C ha{sup -1} was in the soil.

Lasco, R.D.; Sales, R.F.; Estrella, R.; Saplaco, S.R.; Castillo, A.S.A.; Cruz, R.V.O.; Pulhin, F.B. [University of Philippines Los Banos, Laguna (Philippines). College of Forestry & Natural Resources Environmental Forestry Programme

2001-07-01

165

Assessment of the European Guide for Risk Prevention in Small Fishing Vessels. Guide applicability in Polish coastal fishing.  

UK PubMed Central (United Kingdom)

The European Commission--The Directorate General of Employment, Social Affairs, and Equal Opportunities is going to publish the European Guide for Risk Prevention in Small Fishing Vessels. The legislative basis was the Report COM (2009) 599 on the practical implementation of Health and Safety at Work Directives 93/103/EC (fishing vessels) and 92/29/EEC (medical treatment on board vessels), which recommended the drawing up of a non-binding guide for vessels under 15 m in length. The Guide draft was produced directly by Labour Asociados, SSL, Spain. The organization has asked IIMTM in Gdynia, Poland, to participate in the project of evaluating the draft of the Guide. The testing took place simultaneously and homogenously in other chosen European countries. The results of the assessment are presented below. They indicate some differences and specific challenges faced by fishermen working in small costal boats in the Baltic area. The Guide should take these under consideration.

Je?ewska M; Grubman-Nowak M; Jaremin B; Leszczy?ska I

2011-01-01

166

Assessment of the European Guide for Risk Prevention in Small Fishing Vessels. Guide applicability in Polish coastal fishing.  

Science.gov (United States)

The European Commission--The Directorate General of Employment, Social Affairs, and Equal Opportunities is going to publish the European Guide for Risk Prevention in Small Fishing Vessels. The legislative basis was the Report COM (2009) 599 on the practical implementation of Health and Safety at Work Directives 93/103/EC (fishing vessels) and 92/29/EEC (medical treatment on board vessels), which recommended the drawing up of a non-binding guide for vessels under 15 m in length. The Guide draft was produced directly by Labour Asociados, SSL, Spain. The organization has asked IIMTM in Gdynia, Poland, to participate in the project of evaluating the draft of the Guide. The testing took place simultaneously and homogenously in other chosen European countries. The results of the assessment are presented below. They indicate some differences and specific challenges faced by fishermen working in small costal boats in the Baltic area. The Guide should take these under consideration. PMID:22544505

Je?ewska, Maria; Grubman-Nowak, Marta; Jaremin, Bogdan; Leszczy?ska, Irena

2011-01-01

167

Impact of entrainment and impingement on fish populations in the Hudson River Estuary. Volume II. Impingement impact analyses, evaluations of alternative screening devices, and critiques of utility testimony relating to density-dependent growth, the age-composition of the striped bass spawning stock, and the LMS real-time life cycle model  

Energy Technology Data Exchange (ETDEWEB)

This volume includes a series of four exhibits relating to impacts of impingement on fish populations, together with a collection of critical evaluations of testimony prepared for the utilities by their consultants. The first exhibit is a quantitative evaluation of four sources of bias (collection efficiency, reimpingement, impingement on inoperative screens, and impingement survival) affecting estimates of the number of fish killed at Hudson River power plants. The two following exhibits contain, respectively, a detailed assessment of the impact of impingement on the Hudson River white perch population and estimates of conditional impingement mortality rates for seven Hudson River fish populations. The fourth exhibit is an evaluation of the engineering feasibility and potential biological effectiveness of several types of modified intake structures proposed as alternatives to cooling towers for reducing impingement impacts. The remainder of Volume II consists of critical evaluations of the utilities' empirical evidence for the existence of density-dependent growth in young-of-the-year striped bass and white perch, of their estimate of the age-composition of the striped bass spawning stock in the Hudson River, and of their use of the Lawler, Matusky, and Skelly (LMS) Real-Time Life Cycle Model to estimate the impact of entrainment and impingement on the Hudson River striped bass population.

Barnthouse, L. W.; Van Winkle, W.; Golumbek, J.; Cada, G. F.; Goodyear, C. P.; Christensen, S. W.; Cannon, J. B.; Lee, D. W.

1982-04-01

168

Population dynamics and stock assessment for Octopus maya (Cephalopoda:Octopodidae) fishery in the Campeche Bank, Gulf of Mexico  

Directory of Open Access Journals (Sweden)

Full Text Available The octopus (Octopus maya) is one of the most important fish resources in the Mexican Gulf of Mexico with a mean annual yield of 9000 ton, and a reasonable number of jobs created; O. maya represents 80% of the total octopus catch, followed by Octopus vulgaris. There are two artisanal fleets based on Octopus maya and a middle-size fleet that covers both species. Catch-at-length structured data from the artisanal fleets, for the 1994 season (August 1st to December 15th) were used to analyze the O. maya population dynamics and stock and to estimate the current level of exploitation. Von Bertalanffy growth parameters were: L = 252 mm, mantle length; K=1.4 year -1; oscillation parameters C=1.0, WP=0.6; and tz=0.842 years. A rough estimate of natural mortality was M=2.2, total mortality from catch curve Z=8.77, and exploitation rate F/Z=0.75. This last value suggests an intensive exploitation, even when yield per recruit analysis indicates both fleets may increase the minimum legal size on about 10% to increase yields. The length-based VPA also shows that the stock is being exploited under its maximum acceptable biological limit. These apparently contradictory results are explained by biological and behavioral characteristics of this species. Because most females die after reproduction, a new gross estimation of natural mortality was computed as M=3.3. The new estimate of exploitation rate was F/Z=0.57. This new value coincides with results from the length-VPA and the Thompson and Bell methods, the former suggesting that a reduction of 20% in fishing mortality may provide larger yields. This fishery resource is fully exploited and current management measures must be revised to sustain and probably optimize yields.Octopus maya es uno de los recursos pesqueros más importantes del Golfo de México, con rendimientos anuales promedio de 9 000 t, y constituye el 80% de la captura total, seguido por O. vulgaris. En la pesquería participan dos flotas artesanales sobre O. maya, y una de mediana altura capturando ambas especies. Datos de frecuencia de longitudes de la captura para la temporada de pesca 1994 (Agosto 1° a Diciembre 15) fueron usados para analizar la dinámica poblacional y el estado de explotación de O. maya. Los parámetros del modelo de von Bertalanffy fueron: L° = 252 mm longitud de manto, K = 1.4 años-1, C = 1.0 y WP = 0.6, y tZ = 0.842 años. Una estimación inicial de la mortalidad natural fue M = 2.2, la mortalidad total Z = 8.77, y tasa de explotación F/Z = 0.75, lo cual sugiere una intensa explotación. El análisis de rendimiento por recluta indica que podría aumentarse la talla mínima legal para incrementar los rendimientos. El VPA indica un recurso explotado al límite de su capacidad biológica. Debido a que las hembras mueren después de la reproducción, una nueva estimación de mortalidad natural, M = 3.3, y tasa de explotación, F/Z = 0.57 fueron obtenidas, coincidiendo con los resultados del VPA basado en longitudes y el método de Thompson y Bell.

Francisco Arreguín-Sánchez; Manuel J Solís -Ramírez; María E González de la Rosa

2000-01-01

169

Problems of stock definition in estimating relative contributions of Atlantic striped bass to the coastal fishery  

Science.gov (United States)

Stock contribution studies of mixed-stock fisheries rely on the application of classification algorithms to samples of unknown origin. Although the performance of these algorithms can be assessed, there are no guidelines regarding decisions about including minor stocks, pooling stocks into regional groups, or sampling discrete substocks to adequately characterize a stock. We examined these questions for striped bass Morone saxatilis of the U.S. Atlantic coast by applying linear discriminant functions to meristic and morphometric data from fish collected from spawning areas. Some of our samples were from the Hudson and Roanoke rivers and four tributaries of the Chesapeake Bay. We also collected fish of mixed-stock origin from the Atlantic Ocean near Montauk, New York. Inclusion of the minor stock from the Roanoke River in the classification algorithm decreased the correct-classification rate, whereas grouping of the Roanoke River and Chesapeake Bay stock into a regional (''southern'') group increased the overall resolution. The increased resolution was offset by our inability to obtain separate contribution estimates of the groups that were pooled. Although multivariate analysis of variance indicated significant differences among Chesapeake Bay substocks, increasing the number of substocks in the discriminant analysis decreased the overall correct-classification rate. Although the inclusion of one, two, three, or four substocks in the classification algorithm did not greatly affect the overall correct-classification rates, the specific combination of substocks significantly affected the relative contribution estimates derived from the mixed-stock sample. Future studies of this kind must balance the costs and benefits of including minor stocks and would profit from examination of the variation in discriminant characters among all Chesapeake Bay substocks.

Waldman, John R.; Fabrizio, Mary C.

1994-01-01

170

A quantitative health assessment index for rapid evaluation of fish condition in the field  

Energy Technology Data Exchange (ETDEWEB)

The health assessment index (HAI) is an extension and refinement of a previously published field necropsy system. The HAI is a quantitative index that allows statistical comparisons of fish health among data sets. Index variables are assigned numerical values based on the degree of severity or damage incurred by an organ or tissue from environmental stressors. This approach has been used to evaluate the general health status of fish populations in a wide range of reservoir types in the Tennessee River basin (North Carolina, Tennessee, Alabama, Kentucky), in Hartwell Reservoir (Georgia, South Carolina) that is contaminated by polychlorinated biphenyls, and in the Pigeon River (Tennessee, North Carolina) that receives effluents from a bleaches kraft mill. The ability of the HAI to accurately characterize the health of fish in these systems was evaluated by comparing this index to other types of fish health measures (contaminant, bioindicator, and reproductive analysis) made at the same time as the HAI. In all cases, the HAI demonstrated the same pattern of fish health status between sites as did each of the other more sophisticated health assessment methods. The HAI has proven to be a simple and inexpensive means of rapidly assessing general fish health in field situations. 29 refs., 5 tabs.

Adams, S.M. (Oak Ridge National Laboratory, TN (United States)); Brown, A.M. (Tennessee Valley Authority, Norris (United States)); Goede, R.W. (Utah Division of Wildlife Resources, Logan (United States))

1993-01-01

171

Some population parameters as bioindicators to assess the "reserve effect" on the fish assemblage  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Four population parameters were studied to use them as bioindicators to assess the effect of protection on the fish assemblage. Abundance and diversity were poor correlated with protection. Richness and size were more correlated with it, being suitable to assess more efficiently the "reserve effet"....

Bayle Sempere, Just T.; Ramos Esplá, Alfonso Ángel

172

Factors in exposure assessment: ethnic and socioeconomic differences in fishing and consumption of fish caught along the Savannah River.  

Science.gov (United States)

South Carolina has issued fish consumption advisories for the Savannah River based on mercury and radionuclide levels. We examine differences in fishing rates and fish consumption of 258 people interviewed while fishing along the Savannah River, as a function of age, education, ethnicity, employment history, and income, and test the assumption that the average consumption of fish is less than the recreational value of 19 kg/year assumed by risk assessors. Ethnicity and education contributed significantly to explaining variations in number of fish meals per month, serving size, and total quantity of fish consumed per year. Blacks fished more often, ate more fish meals of slightly larger serving sizes, and consumed more fish per year than did Whites. Although education and income were correlated, education contributed most significantly to behavior; people who did not graduate from high school ate fish more often, ate more fish per year, and ate more whole fish than people who graduated from high school. Computing consumption of fish for each person individually indicates that (1) people who eat fish more often also eat larger portions, (2) a substantial number of people consume more than the amount of fish used to compute risk to recreational fishermen, (3) some people consume more than the subsistence level default assumption (50 kg/year) and (4) Blacks consume more fish per year than Whites, putting them at greater risk from contaminants in fish. Overall, ethnicity, age, and education contributed to variations in fishing behavior and consumption. PMID:10765415

Burger, J; Stephens, W L; Boring, C S; Kuklinski, M; Gibbons, J W; Gochfeld, M

1999-06-01

173

Factors in exposure assessment: ethnic and socioeconomic differences in fishing and consumption of fish caught along the Savannah River.  

UK PubMed Central (United Kingdom)

South Carolina has issued fish consumption advisories for the Savannah River based on mercury and radionuclide levels. We examine differences in fishing rates and fish consumption of 258 people interviewed while fishing along the Savannah River, as a function of age, education, ethnicity, employment history, and income, and test the assumption that the average consumption of fish is less than the recreational value of 19 kg/year assumed by risk assessors. Ethnicity and education contributed significantly to explaining variations in number of fish meals per month, serving size, and total quantity of fish consumed per year. Blacks fished more often, ate more fish meals of slightly larger serving sizes, and consumed more fish per year than did Whites. Although education and income were correlated, education contributed most significantly to behavior; people who did not graduate from high school ate fish more often, ate more fish per year, and ate more whole fish than people who graduated from high school. Computing consumption of fish for each person individually indicates that (1) people who eat fish more often also eat larger portions, (2) a substantial number of people consume more than the amount of fish used to compute risk to recreational fishermen, (3) some people consume more than the subsistence level default assumption (50 kg/year) and (4) Blacks consume more fish per year than Whites, putting them at greater risk from contaminants in fish. Overall, ethnicity, age, and education contributed to variations in fishing behavior and consumption.

Burger J; Stephens WL Jr; Boring CS; Kuklinski M; Gibbons JW; Gochfeld M

1999-06-01

174

Assessment of physiological strain in inland fishing activity  

Directory of Open Access Journals (Sweden)

Full Text Available Ten fishermen aged between 19 and 48 years of age, were examined in the field during inland fishing activity, which they perform individually. Physiological strain in terms of heart rate varied between 86 and 115 beats/min with mean net cardiac cost of 32 beats/min. The average relative cardiac cost was 36%. Analysis of physiological responses revealed that the recommended limits of cardiac strain indices were surpassed during the majority of the fishing period. Average energy cost was estimated to be 3.3 kcal.min-1, which was about 34% of the VO2max. Average intensity of the workload entailed in the whole fishing shift appeared to be moderate and acceptable. Furthermore, the heat load in the working situation did not appear to be a serious threat to the health of the workers. Analysis of work revealed more static exertions in the work. To reduce the postural load and musculoskeletal discomforts of the fishermen, ergonomic interventions are required, which represents a further scope of study.

Biswas R; Samanta A

2006-01-01

175

Mercury contamination in human hair and fish from Cambodia: levels, specific accumulation and risk assessment  

Energy Technology Data Exchange (ETDEWEB)

Mercury (Hg) concentrations in human hair and fish samples from Phnom Penh, Kien Svay, Tomnup Rolork and Batrong, Cambodia, collected in November 1999 and December 2000 were determined to understand the status of contamination, and age- and sex-dependent accumulation in humans and to assess the intake of mercury via fish consumption. Mercury concentrations in human hair ranged from 0.54 to 190 {mu}g/g dry wt. About 3% of the samples contained Hg levels exceeding the no observed adverse effects level (NOAEL) of WHO (50 {mu}g/g) and the levels in some hair samples of women also exceeded the NOAEL (10 {mu}g/g) associated with fetus neurotoxicity. A weak but significant positive correlation was observed between age and Hg levels in hair of residents. Mercury concentrations in muscle of marine and freshwater fish from Cambodia ranged from <0.01 to 0.96 {mu}g/g wet wt. Mercury intake rates were estimated on the basis of the Hg content in fish and daily fish consumption. Three samples of marine fish including sharp-tooth snapper and obtuse barracuda, and one sample of sharp-tooth snapper exceeded the guidelines by US EPA and by Joint FAO/WHO Expert Committee on Food Additives (JECFA), respectively, which indicates that some fish specimens examined (9% and 3% for US EPA and JECFA guidelines, respectively) were hazardous for consumption at the ingestion rate of Cambodian people (32.6 g/day). It is suggested that fish is probably the main source of Hg for Cambodian people. However, extremely high Hg concentrations were observed in some individuals and could not be explained by Hg intake from fish consumption, indicating some other contamination sources of Hg in Cambodia. - A source other than fish may be responsible for high Hg in some Cambodians.

Agusa, Tetsuro [Center for Marine Environmental Studies (CMES), Ehime University, Bunkyo-cho 2-5, Matsuyama 790-8577 (Japan); Kunito, Takashi [Department of Environmental Sciences, Faculty of Science, Shinshu University, 3-1-1 Asahi, Matsumoto, Nagano 390-8621 (Japan); Iwata, Hisato [Center for Marine Environmental Studies (CMES), Ehime University, Bunkyo-cho 2-5, Matsuyama 790-8577 (Japan); Monirith, In [Center for Marine Environmental Studies (CMES), Ehime University, Bunkyo-cho 2-5, Matsuyama 790-8577 (Japan); Tana, Touch Seang [Social and Cultural Observation Unit (OBSES) of the Cabinet of the Council of Ministers, Phnom Penh (Cambodia); Subramanian, Annamalai [Center for Marine Environmental Studies (CMES), Ehime University, Bunkyo-cho 2-5, Matsuyama 790-8577 (Japan); Tanabe, Shinsuke [Center for Marine Environmental Studies (CMES), Ehime University, Bunkyo-cho 2-5, Matsuyama 790-8577 (Japan)]. E-mail: shinsuke@agr.ehime-u.ac.jp

2005-03-01

176

Assessment of copper and zinc levels in fish from freshwater ecosystems of Moldova.  

UK PubMed Central (United Kingdom)

PURPOSE: The aim of this work was to assess the levels of copper and zinc in fish from the main freshwater ecosystems of Moldova, in relation with species, habitat, age, sex, season, and development stage. METHODS: Fish from Cyprinidae and Percidae families (Cyprinus carpio, Carassius auratus gibelio, Rutilus rutilus heckeli, Abramis brama, Aristichthys nobilis, Hypophtalmichthys molitrix, Sander lucioperca) were collected from Prut and Dniester rivers, Cuciurgan, Dubasari, and Costesti-Stanca reservoirs, and ponds of farms in the Dniester delta. The Cu and Zn content of fish tissues (skeletal muscles, liver, gonads, gills, skin, and scales) was determined by flame atomic absorption spectrophotometer AAS-3, of water by graphite furnace HGA 900 of AAnalist 400. RESULTS: The level of heavy metals accumulation in muscles of immature fish follows their dynamics in water. The highest concentration of zinc was registered in the gonads of mature fish, and of copper-in the liver. The lowest Cu and Zn contents were recorded in the muscles and are in the United Nations Food and Agriculture Organization safety-permissible levels for human consumption. Cu and Zn contents in muscles of fish depend on specimen age. Their level in fish gonads was sharply increasing during pre-spawning period. During the early developmental stages, the metal concentration in fish eggs and larvae varies within wide limits, but the accumulation pattern is similar in the investigated species. CONCLUSIONS: The fish represent one of the most indicative factors for the estimation of trace metals pollution in freshwater systems and this is important not only for monitoring purposes, but also for the fish culture ones.

Zubcov E; Zubcov N; Ene A; Biletchi L

2012-07-01

177

Development of a spatially distributed model of fish population density for habitat assessment of rivers  

Science.gov (United States)

Flow conditions play an important role in sustaining biodiversity of river ecosystem. However, their relations to freshwater fishes, especially to fish population density, have not been clearly described. This study, therefore, aimed to propose a new methodology to quantitatively link habitat conditions, including flow conditions and other physical conditions, to population density of fish species. We developed a basin-scale fish distribution model by integrating the concept of habitat suitability assessment with a distributed hydrological model (DHM) in order to estimate fish population density with particular attention to flow conditions. Generalized linear model (GLM) was employed to evaluate the relationship between population density of fish species and major environmental factors. The target basin was Sagami River in central Japan, where the river reach was divided into 10 sections by estuary, confluences of tributaries, and river-crossing structures (dams, weirs). The DHM was employed to simulate river discharge from 1998 to 2005, which was used to calculate 10 flow indices including mean discharge, 25th and 75th percentile discharge, duration of low and high flows, number of floods. In addition, 5 water quality parameters and 13 other physical conditions (such as basin area, river width, mean diameter of riverbed material, and number of river-crossing structures upstream and downstream) of each river section were considered as environmental variables. In case of Sagami River, 10 habitat variables among them were then selected based on their correlations to avoid multicollinearity. Finally, the best GLM was developed for each species based on Akaike's information criterion. As results, population densities of 16 fish species in Sagami River were modelled, and correlation coefficients between observed and calculated population densities for 10 species were more than 0.70. The key habitat factors for population density varied among fish species. Minimum discharge (MID) was found to be positively correlated to 9 among 16 fish species. For duration of high and low flows (DHF and DLF), longer DHF/DLF was corresponded to lower population density for 7/6 fish species, respectively, such as Rhinogobius kurodai and Plecoglossus altivelis altivelis. Among physical habitat conditions, sinuosity index (SI, the ratio between actual river section length and straight line length) seems to be the most important parameter for fish population density in Sagami River basin, since it affects 12 out of 16 fish species, followed by mean longitudinal slope (S) and number of downstream dams (NLD). Above results demonstrated the applicability of fish distribution model to provide quantitative information on flow conditions required to maintain fish population, which enabled us to evaluate and project ecological consequences of water resource management policy, such as flood management and water withdrawal.

Sui, Pengzhe; Iwasaki, Akito; Ryo, Masahiro; Saavedra, Oliver; Yoshimura, Chihiro

2013-04-01

178

Lock, stock, and barrel: A comprehensive assessment of the determinants of terror  

Digital Repository Infrastructure Vision for European Research (DRIVER)

We assess the robustness of previous findings on the determinants of terrorism. Using extreme bound analysis, the three most comprehensive terrorism datasets, and focusing on the three most commonly analyzed aspects of terrorist activity, i.e., location, victim, and perpetrator, we re-assess the eff...

Gassebner, Martin; Luechinger, Simon

179

Impact of entrainment and impingement on fish populations in the Hudson River estuary. Volume III. An analysis of the validity of the utilities' stock-recruitment curve-fitting exercise and prior estimation of beta technique. Environmental Sciences Division publication No. 1792  

Energy Technology Data Exchange (ETDEWEB)

This report addresses the validity of the utilities' use of the Ricker stock-recruitment model to extrapolate the combined entrainment-impingement losses of young fish to reductions in the equilibrium population size of adult fish. In our testimony, a methodology was developed and applied to address a single fundamental question: if the Ricker model really did apply to the Hudson River striped bass population, could the utilities' estimates, based on curve-fitting, of the parameter alpha (which controls the impact) be considered reliable. In addition, an analysis is included of the efficacy of an alternative means of estimating alpha, termed the technique of prior estimation of beta (used by the utilities in a report prepared for regulatory hearings on the Cornwall Pumped Storage Project). This validation methodology should also be useful in evaluating inferences drawn in the literature from fits of stock-recruitment models to data obtained from other fish stocks.

Christensen, S. W.; Goodyear, C. P.; Kirk, B. L.

1982-03-01

180

Assessment of micronuclei induction in peripheral erythrocytes of fish exposed to xenobiotics under controlled conditions  

International Nuclear Information System (INIS)

[en] The aim of the present study was to standardize and to assess the predictive value of the cytogenetic analysis by MN test in fish erythrocytes as a biomarker for marine environmental contamination. MN frequency baseline in erythrocytes was evaluated in a number of fish species from a reference area (S. Teresa, La Spezia Gulf) and genotoxic potential of a number of common chemical contaminants and mixtures was determined in fish experimentally exposed in aquarium under controlled conditions. Fish (Scophthalmus maximus) were exposed for 3 weeks to 50 ppb of single chemicals (dialkyl phthalate, bisphenol A, tetrabromodiphenyl ether), 30 ppb nonylphenol and mixtures (North Sea oil and North Sea oil with alkylated phenols). Chromosomal damage was determined as micronuclei (MN) frequency in fish erythrocytes. Nuclear anomalies such as blebbed, notched and lobed nuclei were also recorded. Significant increase in MN frequency was observed in erythrocytes of fish exposed to bisphenol A and tetrabromodiphenylether. Chemical mixture North Sea oil + alkylated phenols induced the highest MN frequency (2.95 micronucleated cells/1000 cells compared to 1 MNcell/1000 cells in control animals). The study results revealed that micronucleus test, as an index of cumulative exposure, appears to be a sensitive model to evaluate genotoxic compounds in fish under controlled conditions

2006-06-01

 
 
 
 
181

Farmed fish welfare-suffering assessment and impact on product quality  

Directory of Open Access Journals (Sweden)

Full Text Available Fish welfare, suffering and the perception of pain were debated, together with several factors reducing infra vitam welfare of farmed fish (genetic, environment, density, malnutrition, starvation, cataracts, deformities, vaccination side effects, transport, handling, confinement, crowding, harvesting, killing method). Behavioural and physiological stress responses were considered as indicators of welfare reduction. The effects of pre-slaughter management practices, and the most commonly used stunning/slaughtering methods on welfare and quality reduction of farmed fish were discussed. A number of indicators can be used to assess fish welfare-suffering, both in a scientific and practical context, such as behavioural, haematic, cellular, tissue post mortem fish stress and quality indicators, but none of them are optimal. The best strategy for a reliable assessment of fish welfare/suffering and their impact on product quality is a multidisciplinary approach that takes into account animal behaviour and the different biochemical and physiological ante mortem and post mortem processes involved: several components, all influenced in a similar way by the same condition, suggest real welfare and quality reduction.

Bianca Maria Poli

2010-01-01

182

Health risk assessment for consumption of fish originating from ponds near Dabaoshan mine, South China.  

UK PubMed Central (United Kingdom)

Mining effluents are a potential source of toxic metals in the surrounding aquatic ecosystem and pose a potential health risk to humans from fish consumption. The objective of this paper is to assess the impact of the long-term Dabaoshan mining operation on heavy metal accumulation in different fish species. Heavy metal accumulation (lead (Pb), cadmium (Cd), zinc (Zn), and copper (Cu)) in four tissues (liver, muscle, intestine, and gills) of five carp species (Hypophthalmichthys molitrix, Ctenopharyngodon idellus, Megalobrama amblycephala, Aristichthys nobilis, and Carassius auratus auratus) from two fishponds exposed to effluent waters from Dabaoshan mine, South China. The bioaccumulation factor (BAF) and target hazard quotients were calculated to assess potential health risks to local residents through fish consumption. Levels of heavy metals varied depending on the analyzed tissues. C. auratus auratus accumulated the higher Pb, Cd, Zn, and Cu in the intestine compared with other fish species. Liver of all five species contained high concentrations of Pb, Cd, Zn, and Cu. The BAF for the studied metals showed a descending order of Cd>Zn>Cu>Pb for fishpond 1 and Zn>Cd>Cu>Pb for fishpond 2. Risk assessments suggested that potential human health risk may be present due to high Pb and Cd concentration in the muscle of some fish species exceeding the national and international limits, although the target hazard quotients were less than one.

Zhuang P; Li ZA; McBride MB; Zou B; Wang G

2013-08-01

183

EFFICACITÉ DES REPEUPLEMENTS EN TRUITES (Salmo trutta L. et Oncorhynchus mykiss W.) DE UN AN POUR LA PÊCHE PROFESSIONNELLE AUX FILETS ET LA PÊCHE AMATEUR À LA TRAÎNE DANS LE LAC DU BOURGET EFFICIENCY OF ONE YEAR OLD TROUT (Salmo trutta L.and Oncorhynchus mykiss W.) STOCKING FOR PROFESSIONNAL NETTING AND RECREATIONAL FISHING IN BOATS IN LAKE BOURGET  

Directory of Open Access Journals (Sweden)

Full Text Available L’étude visait à évaluer l’efficacité d’une pratique de repeuplement courante dans le lac du Bourget (4 400 ha) consistant à déverser directement en lac des truitelles de un an avec pour objectif de soutenir des captures de truite du lac. Les recaptures par la pêche amateur et professionnelle ont été évaluées pour un lot de 15 900 truites fario (Salmo trutta L.) domestiques de un an (longueur totale moyenne de 177 mm) déversées fin avril 1988. Elles sont respectivement de 3,8 % (33 kg/1 000 truitelles) pour la pêche professionnelle aux filets maillants et de 1,0 % (6 kg/1 000 truitelles) pour la pêche amateur à la traîne en bateau. En relation avec une forte croissance, l’essentiel des recaptures a été réalisé en fin de saison 1988 et en début de saison 1989. Les recaptures par la pêche professionnelle aux filets maillants ont été évaluées pour un lot de 10 000 truitelles fario domestiques (longueur totale moyenne de 179 mm) en comparaison avec un lot de 10 800 truitelles arc en ciel (Oncorhynchus mykiss W.) de un an (longueur totale moyenne de 219 mm) déversées en mai 1990. Les recaptures ont été respectivement de 3,2 % (20 kg/1 000 truitelles) pour la fario et de 7,0 % (42 kg/1 000 truitelles) pour l’arc en ciel. Pour la truite arc-en-ciel, l’essentiel des recaptures a été réalisé très rapidement sur une période brève : milieu et fin de saison 1990. Pour le lot de fario, l’essentiel de l’exploitation a été réalisé sur une période courte mais un peu plus tardive (fin de saison 1990 et début de saison 1991) que pour l’arc-en-ciel. Les repeuplements en mai avec des truitelles domestiques de un an conduisent effectivement à des captures de truite de lac en lac mais avec un rendement plutôt faible et en prenant des risques (écologiques et pathologiques). Ceci suggère de mobiliser les efforts de gestion vers la production naturelle et donc durable de la ressource truite de lac dans le lac du Bourget. The study aimed to assess the efficiency of a frequent stocking practice in Lake Bourget (4 400 ha) consisting in stocking directly in the lake one-year-old trout with the objective of sustaining catches of lake dwelling trout in the lake. The recaptures by recreational fishing in boat and professionnal fishing with nets were evaluated for a batch of 15 900 one year old domestic brown trout (Salmo trutta L.) stocked in April 1988 (mean total length: 177 mm). They were respectively 3.8% (33 kg/1 000) for the professional fishing and 1.0% (20 kg/1 000) for the recreational fishing. In relation with a high growth rate, most of the catches have been realized quickly, at the end of the 1988 fishing season and at the beginning of the 1989 fishing season. The recaptures by professional fishing have been evaluated for a batch of 10 000 domestic brown trout (mean total length 179 mm) in comparison with a batch of 10 800 rainbow trout (Oncorhynchus mykiss W.) stocked in Lake Bourget in May 1990 (mean total length of 219 mm). The recapture rates were evaluated at 3.2% (20 kg/1 000) for the brown trout and 7.0% (42 kg/1 000) for the rainbow trout. For the rainbow trout, most of the catches have been realized very quickly during a short period at the middle and at the end of the 1990 fishing season. For the brown trout, most of the catches have also been realized during a rather short but later period (end of the 1990 fishing season and beginning of the 1991 fishing season). The stockings in May with one-year-old trout sustained effectively catches of lake dwelling trout in lake but with a rather poor return rate and in taking some ecological and sanitary risks. This suggests to mobilize the management efforts for the natural production of a renewable trout resource in Lake Bourget system.

CHAMPIGNEULLE A.; CACHERA S.

2008-01-01

184

Developing a Bayesian framework for stock assessment and decision analysis of the red sea urchin fishery in Baja California, Mexico/ Desarrollo de un marco Bayesiano para la valoración del stock y el análisis de decisión de la pesquería del erizo rojo en Baja California, México  

Scientific Electronic Library Online (English)

Full Text Available Abstract in spanish La pesquería del erizo rojo (Strongylocentrotus franciscanus) es importante para la economía de Baja California (México). Su pesca comercial se inició a principios de los años 70 como resultado de la expansión de su mercado de exportación; sin embargo, se ha detectado una baja sustancial en sus capturas y abundancia desde 1986. Dada la falta de un índice de abundancia relativa independiente de la pesquería para todas las áreas de captura, se utilizaron datos de (more) CPUE y captura para llevar a cabo una valoración del stock del erizo rojo y realizar un análisis de decisión con relación a su pesquería. La dinámica poblacional fue descrita mediante el modelo de biomasa excedente de Schaefer usando métodos Bayesianos para estimar los parámetros del modelo y para proyectar la dinámica poblacional de la especie bajo diferentes escenarios de manejo, los cuales incluyeron estrategias de tasas de explotación constantes y capturas constantes. Los resultados sugieren que el stock actual es sólo 17% de la bioma virgen y que, para una estrategia de captura constante, un incremento del 10% en el nivel de captura actual podría causar el colapso de la pesquería en 20 años. Los resultados de las simulaciones sugieren que una estrategia de tasa de explotación constante entre 15% y 25% causaría que la población se recuperara y la captura se maximizara en 2024. Mayores niveles de explotación incrementarían la probabilidad de que la biomasa sea menor al 40% de la capacidad de carga de la población. Abstract in english The red sea urchin (Strongylocentrotus franciscanus) fishery is of importance to the economy of Baja California (Mexico). The commercial fishery started in the early 1970s as a result of expanding export markets, but has experienced substantial decline in landings and abundance since 1986. Fishery-independent surveys have not been conducted for all fishing areas, thus CPUE and catch data were used to conduct a stock assessment and decision analysis for the red sea urchin (more) stock. The red sea urchin population dynamics was described with the Schaefer biomass dynamic model. Bayesian approaches were used for the estimation of the model parameters and for projecting the population dynamics of the species under different management scenarios, including constant harvest rate and constant catch strategies. This study suggests that the current stock is only 17% of the virgin stock biomass and that, for a constant catch policy, a 10% increase in the current catch rate could potentially cause the collapse of the fishery in 20 years. Simulation results suggested that a constant harvest rate between 15% and 25% would cause the population to recover and maximize the catch in 2024. Higher harvest rate levels would increase the probability of the biomass being less than 40% of the population carrying capacity.

Jurado-Molina, J; Palleiro-Nayar, JS; Gutiérrez, NL

2009-06-01

185

Development of methods for assessing the vulnerability of Australian residential building stock to severe wind  

International Nuclear Information System (INIS)

Knowledge of the degree of damage to residential structures expected from severe wind is used to study the benefits from adaptation strategies developed in response to expected changes in wind severity due to climate change. This study will inform government, the insurance industry and provide emergency services with estimates of expected damage. A series of heuristic wind vulnerability curves for Australian residential structures has been developed. In order to provide rigor to the heuristic curves and to enable quantitative assessment to be made of adaptation strategies, work has commenced to produce a simulation tool to quantitatively assess damage to buildings from severe wind. The simulation tool accounts for variability in wind profile, shielding, structural strength, pressure coefficients, building orientation, component self weights, debris damage and water ingress via a Monte Carlo approach. The software takes a component-based approach to modelling building vulnerability. It is based on the premise that overall building damage is strongly related to the failure of key components (i.e. connections). If these failures can be ascertained, and associated damage from debris and water penetration reliably estimated, scenarios of complete building damage can be assessed. This approach has been developed with varying degrees of rigor by researchers around the world and is best practice for the insurance industry.

2010-01-01

186

Performance Assessment of the Food Industry of Tehran Stock Exchange Based on Balanced Score Card (BSC) Technique  

Directory of Open Access Journals (Sweden)

Full Text Available Major objective of the present paper was to study the role of balanced score card regarding performance assessment of companies listed in food and beverage industry in the stock exchange. This survey is descriptive and is regarded as a quasi-experimental research plan (Ex-Post design). The statistical population included 200 managers and research sample consisted of 99 persons based on Cochran formula. Questionnaire was used for data collection. Frequency tables and appropriate diagrams were applied to describe data and inferential statistics methods such as student's t-test were used to confirm or reject hypotheses. Variance analysis and t-test for two independent samples were used to study the impact of personal characteristics on responding to the hypotheses. Ranking of improvement degree of indexes for realization of purposes and determining rank of each factor was studied using Friedman test. Results of testing hypotheses reveal it is necessary for organizations to emphasize internal processes more given that planning and implementing efficient and suitable processes in the organization is led to offering appropriate services. About growth and learning scope it is notable that since employees are major capitals of the organization, special attention must be paid to this sector in order to satisfy employees and provide long-term benefits of the organization.

Morteza Asadi; Javad Mehrabi; Saharnaz Mohseni; Mohammad Hasan Tanhaei

2013-01-01

187

Risk assessments of human exposure to bioaccessible phthalate esters through market fish consumption.  

UK PubMed Central (United Kingdom)

The bioaccessibility of phthalate esters in 20 fish species collected from Hong Kong market was evaluated using an in vitro gastrointestinal model. The ?phthalate ester concentration detected in fresh water fish ranged from 1.66 to 3.14?g/g wet weight (ww) and in marine fish ranged from 1.57 to 7.10?g/g ww, respectively. di-2-Ethylhexyl phthalate (DEHP) and di-n-butyl phthalate (DBP) were the predominant compounds in both freshwater fish and marine fish. The digestible concentrations of phthalate esters ranged from 0.20 to 1.23?g/g ww (mean 0.35?g/g ww), and account for 2.44 to 45.5% (mean 16.8%) for raw concentrations of phthalate esters. In the present study, the accumulation ratio Rnn value of all phthalate esters was greater than 1 except for diisobutyl phthalate (DIBP), DBP and di-n-hexyl phthalate (DHP), suggesting that these phthalate esters could be accumulated during gastrointestinal digestion. Based on this health risk assessment, most of fish species were considered safe for consumption, however Hong Kong residents should take caution when consuming Mud carp and Bighead carp.

Cheng Z; Nie XP; Wang HS; Wong MH

2013-07-01

188

Assessing the potential for fish predation to impact zebra mussels (Dreissena polymorpha): Insight from bioenergetics models  

Science.gov (United States)

Rates of annual food consumption and biomass were modeled for several fish species across representative rivers and lakes in eastern North America. Results were combined to assess the relative potential of fish predation to impact zebra mussels (Dreissena polymorpha). Predicted annual food consumption by fishes in southern waters was over 100% greater than that in northern systems because of warmer annual water temperatures and presumed increases in metabolic demand. Although generally increasing with latitude, biomasses of several key zebra mussel fish predators did not change significantly across latitudes. Biomasses of some less abundant fish predators did increase significantly with latitude, but increases were not of the magnitude to offset predicted decreases in food consumption. Our results generally support the premise that fishes in rivers and lakes of the southern United States (U.S.) have inherently greater potential to impact zebra mussels by predation. Our simulations may provide a partial explanation of why zebra mussel invasions have not been as rapid and widespread in southern U.S. waters compared to the Great Lakes region. ?? Blackwell Munksgaard, 2004.

Eggleton, M. A.; Miranda, L. E.; Kirk, J. P.

2004-01-01

189

Risk assessments of human exposure to bioaccessible phthalate esters through market fish consumption.  

Science.gov (United States)

The bioaccessibility of phthalate esters in 20 fish species collected from Hong Kong market was evaluated using an in vitro gastrointestinal model. The ?phthalate ester concentration detected in fresh water fish ranged from 1.66 to 3.14?g/g wet weight (ww) and in marine fish ranged from 1.57 to 7.10?g/g ww, respectively. di-2-Ethylhexyl phthalate (DEHP) and di-n-butyl phthalate (DBP) were the predominant compounds in both freshwater fish and marine fish. The digestible concentrations of phthalate esters ranged from 0.20 to 1.23?g/g ww (mean 0.35?g/g ww), and account for 2.44 to 45.5% (mean 16.8%) for raw concentrations of phthalate esters. In the present study, the accumulation ratio Rnn value of all phthalate esters was greater than 1 except for diisobutyl phthalate (DIBP), DBP and di-n-hexyl phthalate (DHP), suggesting that these phthalate esters could be accumulated during gastrointestinal digestion. Based on this health risk assessment, most of fish species were considered safe for consumption, however Hong Kong residents should take caution when consuming Mud carp and Bighead carp. PMID:23688402

Cheng, Zhang; Nie, Xiang-Ping; Wang, Hong-Sheng; Wong, Ming-Hung

2013-07-01

190

A Comparative Assessment of Hydroponically Grown Cereal Crops for the Purification of Aquaculture Wastewater and the Production of Fish Feed  

Directory of Open Access Journals (Sweden)

Full Text Available Hydroponically grown wheat, barley and oats were examined for their ability to remove nutrients from aquaculture wastewater. Wheat, barley and oats seeds were germinated in water in a hydroponics system. The seedlings then received wastewater from an aquaculture system stocked with Arctic charr. During the experiment, the crops grew rapidly and fairly uniformly and showed no signs of mineral deficiency although fungal growth was evident. The average crop heights and yields at harvest were 19.0, 25.5 and 25.2 cm and 64, 59 and 42 t ha-1 for wheat, barley and oats, respectively. The hydroponically grown wheat, barley and oats were able to significantly reduce the pollution load of the aquaculture wastewater. The TS, COD, NH4+-N, NO2--N, NO3--N and PO43--P reductions ranged from 53.3 to 57.7%, from 55.7 to 78.7%, from 76.0 to 80.0% from 85.1 to 92.9%, from 62.1 to 79.3% and from 74.1 to 93.0%, respectively. The compartments containing barley produced the highest quality effluent, which was suitable for reuse in aquaculture operations. The average TS, COD, NH4+-N, NO2--N, NO3--N and PO43--P concentrations and pH of the final effluent from the compartments containing barley were 442, 64, 0.50, 0.02, 5.89 and 0.61 mg L-1 and 6.65, respectively. The nutritive value of the three wastewater grown crops was assessed to determine the suitability of using the plants as a component in fish feed. The three terrestrial crops meet the energy, fat, Ca, Mg, P, Na, S and Mn dietary requirements of aquatic animals, exceed the carbohydrate, crude fiber, Cl, K, Cu, Fe, Se and Zn requirements of fish and shellfish and do not contain sufficient amounts of protein to meet the dietary requirements of fish and shellfish. The crops will require supplementation with a high protein source that contains low concentrations of carbohydrates, crude fiber, Cl, K, Cu, Fe, Se and Zn. Common protein sources that could be used for supplementation included fishmeal, bone meal and blood meal.

A. M. Snow; A. M. Snow; Abdel E. Ghaly

2008-01-01

191

Assessment of fish mortality at the Rance tidal power barrage, Brittany, France.  

Science.gov (United States)

This report describes the results of three weeks field work carried out on the Rance Estuary in August 1991. The objectives were to make a preliminary assessment of the relative frequency with which dead fish accumulate in the Rance barrage lock pit; to a...

S. J. Lockwood S. M. Baynes

1992-01-01

192

Population structure and stock assessment of Hoplias malabaricus (Characiformes: Erythrinidae) caught by artisanal fishermen in river-reservoir transition area in Brazil  

Scientific Electronic Library Online (English)

Full Text Available Abstract in spanish Hoplias malabaricus representa una alternativa económica viable para los pescadores artesanales que viven a la orilla de ríos que actualmente cuentan con represas en Brasil. El objeto del presente estudio fue evaluar la dinámica de la reproducción, alimentación, crecimiento y nivel de explotación de la especie nativa Hoplias malabaricus, capturada por pescadores artesanales en la zona de transición entre el río Paranapanema y el Embalse de Jurumirim. En 2005, los (more) especimenes de H. malabaricus se obtuvieron utilizando redes agalleras de forma mensual y se registraron las siguientes características y datos biológicos de cada uno: longitud estándar, peso corporal, sexo, estadio reproductivo, peso de las gónadas y contenido estomacal. Estos datos fueron utilizados para estimar la proporción sexual, el período reproductivo y los hábitos alimenticios. Para evaluar los parámetros de crecimiento y el grado de explotación, los datos de frecuencia de la longitud estándar fueron analizados utilizando el software FISAT a través de la rutina ELEFAN I. Según los resultados obtenidos, la proporción sexual fue de 0.8:1 (macho:hembra); la reproducción fue observada durante todo el año, pero sobre todo en la primavera y el verano. El hábito alimentario fue piscívoro. Los parámetros de crecimiento y mortalidad fueron estimados en: L?=35.18cm, k=0.32/año; longevidad= 9.3, Z=1.25/año, M=0.63/año y F=0.62/año. La relación longitud-peso fue: Wt=-3.1663+2.7456lnLp. El análisis de rendimiento por recluta estimó los siguientes valores: E=0.496, Emax=0.916, E0.1=0.701 y E0.5=0.378. Puede concluirse que la población de H. malabaricus en la región estudiada todavía no está siendo altamente explotada. Abstract in english Hoplias malabaricus is a viable economic alternative for artisanal fishermen who used to live on the banks of rivers that now are dammed in Brazil. In order to preserve the species? natural stock, the main objectives of this study were to obtain bio-ecological information on this species reproduction, feeding dynamics and the description of the extent of its exploitation in river-reservoir transition area in Brazil. This way, from January to December 2005, different fish (more) ery catches were made with gill nets by artisanal fishermen, and a total of 426 individual H. malabaricus were obtained and sampled. From each specimen, the following biometric and biological data were analyzed: standard length, total weight, stomach contents, reproductive data such as sex, weight and gonadal maturation stage; with these data we estimated sex ratio, reproduction period and feeding habits. To assess growth parameters and infer on the degree of exploitation, the standard length frequency data were analysed using the FISAT (ELEFAN I) computer program. Data revealed a sex ratio of 0.8:1 (M:F), that reproduction occurs all year around, being more intense during spring and summer; it also showed that H. malabaricus is piscivorous. The growth parameters and mortality were estimated at: L?=35.18cm, k=0.32 year, longevity=9.3 years, Z=1.25 years, M=0.63 year and F=0.62 year. The weight-length relationship was: ln Wt=-3.1663+2.7456 ln Lp. The yield-per-recruit analysis produced the following values: E=0.496, Emax=0.916, E0.1=0.701 and E0.5=0.378. Overall, our data suggest that the stock of H. malabaricus is not yet overfished in the studied area. Rev. Biol. Trop. 59 (1): 71-83. Epub 2011 March 01.

Costa Novaes, José Luís; Carvalho, Edmir Daniel

2011-03-01

193

About stock markets predictability  

Directory of Open Access Journals (Sweden)

Full Text Available We argue that the financial markets have a predetermined outcome. They behave deterministically but appear to follow random patterns. Stock prices have nothing to do with future expectations; they are a reflection of previous convictions coming from the confident investors. A financial crisis is the result of the lack of confidence that characterizes a market moments before the crisis. Stocks returns are perfectly correlated to each other and it is possible to obtain high gains consistently. Finally we provide a different way of assessing risk and suggest a method to sense future performances.

Hicham Benjelloun

2011-01-01

194

Environmental Assessment for the Transfer of 1100 AREA, Southern Rail Connection and Rolling Stock, Hanford Site, Richland, Washington  

Energy Technology Data Exchange (ETDEWEB)

This environmental assessment (EA) has been prepared to assess potential environmental impacts associated with the U.S. Department of Energy's proposed action: the transfer of the 1100 Area, southern rail connection and rolling stock to a non-federal entity. Impact information contained herein will be used by the U.S. Department of Energy, Richland Operations Office Manager, to determine if the proposed action is a major federal action significantly affecting the quality of the human environment. If the proposed action is determined to be major and significant, an environmental impact statement will be prepared. If the proposed action is determined not to be major and significant, a Finding of No Significant Impact (FONSI) will be issued and the action can proceed. Criteria used to evaluate significance can be found in Title 40, Code of Federal Regulations (CFR) 1508.27. This EA was prepared in compliance with the ''National Environmental Policy Act'' (NEPA) of 1969, as amended, the Council on Environmental Quality (CEQ) Regulations for Implementing the Procedural Provisions of NEPA (40 CFR 1500-1508), and the U.S. Department of Energy Implementing Procedures for NEPA (10 CFR 1021). The following is a description of each section of the EA. (1) Purpose and Need for Action. This provides a brief statement concerning the problem or opportunity the U.S. Department of Energy is addressing with the proposed action. As necessary, background information is provided. (2) Description of the Proposed Action. A description with sufficient detail to identify potential environmental impacts is provided. (3) Alternatives to the Proposed Action. Reasonable alternative actions, which would address the Purpose and Need, are described. A no action alternative, as required by 10 CFR 1021, also is described. (4) Affected Environment. This provides a brief description of the locale in which the proposed action takes place, and which may be environmentally impacted. (5) Environmental Impacts. The range of environmental impacts, beneficial and adverse, are described for the proposed action. Impacts of alternatives briefly are discussed. (6) Permits and Regulatory Requirements. A brief description of permits and regulatory requirements for the proposed action is provided. (7) Organizations Consulted. Any outside agencies, groups, or individuals contacted as part of environmental assessment documentation preparation are listed. (8) References. Documents used to provide information or data are listed. The appendices contain additional information necessary to support an understanding of the proposed action, alternatives, and potential impacts is provided. Comments resulting from review of the environmental assessment by states and tribes or other stakeholders and the response to those comments will be included in the appendices.

N/A

1998-08-01

195

Assessment of heavy metals in two commercial fish species of four Turkish seas.  

UK PubMed Central (United Kingdom)

There is an increasingly need to assess the contaminant levels in fish as indicators of the health and well-being of both the fish and their consumers, including humans. Fish samples were collected through the coastal waters of Turkey and the contents of cadmium, copper, chrome, copper, iron, manganese, nickel, zinc and lead in the liver and muscle tissues were determined by ICP-AES. The highest levels of each metal were found in the liver and this was followed by the muscle in both species. Among the metals analyzed, Cu, Zn and Fe were the most abundant in the different tissues while Cd and Pb were the least abundant both in Mullus barbatus (red mullet) and Merlangius merlangus (whiting). Regional changes in metal (Cd, Cu, Pb, Fe and Zn) concentration were observed in the tissues of both species, but these variations may not influence consumption advisories.

Tepe Y; Türkmen M; Türkmen A

2008-11-01

196

Environmental effect assessment for sexual endocrine-disrupting chemicals: Fish testing strategy.  

UK PubMed Central (United Kingdom)

Current standard testing and assessment tools are not designed to identify specific and biologically highly sensitive modes of action of chemicals, such as endocrine disruption. This information, however, can be important to define the relevant endpoints for an assessment and to characterize thresholds of their sublethal, population-relevant effects. Starting a decade ago, compound-specific risk assessment procedures were amended by specifically addressing endocrine-disrupting properties of substances. In 2002, the Conceptual Framework, agreed upon by OECD's Task Force on Endocrine Disrupters Testing and Assessment, did not propose specific testing strategies, and appropriate testing methods had not yet been developed and approved. In the meantime, the OECD Test Guidelines Programme has undertaken important steps to revise established and to develop new test methods, which can be used to identify and quantify effects of endocrine-disrupting chemicals on mammals, birds, amphibians, fish, and invertebrates. For fish testing of endocrine-disrupting chemicals, the first Test Guidelines have recently been adopted by the OECD and validation of further test systems is under progress. Based on these test systems and the experience gained during their validation procedures, we propose a 3-step fish testing strategy: 1) Weight-of-evidence approach for identifying potential sexual endocrine-disrupting chemicals; even after advanced specification of systematic criteria, this step of establishing initial suspicion will still require expert judgment; 2) in vivo evaluation of sexual endocrine-disrupting activity in fish by applying in vivo fish screening assays; sufficient data are available to diagnose the aromatase-inhibition and estrogen-receptor agonist mechanisms of action by indicative endpoints (biomarkers), whereas the ability of the respective biomarkers in the screening assay to identify the estrogen-receptor antagonists and androgen-receptor agonists and antagonists requires further validation; 3) characterization of sexual endocrine-mediated adverse effects including threshold concentrations; in cases when the most sensitive population-relevant endpoints and the most sensitive time window for exposure are known for the mechanisms of action, the fish full life-cycle or 2-generation test, which are the normal definitive tests, might be abbreviated to, e.g., the fish sexual development test. In the European Union, the measurement of indicative endpoints in the definitive test might be crucial for the authorization procedure under REACH and plant-protection products. The results of the definitive tests can be used in existing schemes of compound-specific environmental risk assessments.

Knacker T; Boettcher M; Frische T; Rufli H; Stolzenberg HC; Teigeler M; Zok S; Braunbeck T; Schäfers C

2010-10-01

197

Environmental effect assessment for sexual endocrine-disrupting chemicals: Fish testing strategy.  

Science.gov (United States)

Current standard testing and assessment tools are not designed to identify specific and biologically highly sensitive modes of action of chemicals, such as endocrine disruption. This information, however, can be important to define the relevant endpoints for an assessment and to characterize thresholds of their sublethal, population-relevant effects. Starting a decade ago, compound-specific risk assessment procedures were amended by specifically addressing endocrine-disrupting properties of substances. In 2002, the Conceptual Framework, agreed upon by OECD's Task Force on Endocrine Disrupters Testing and Assessment, did not propose specific testing strategies, and appropriate testing methods had not yet been developed and approved. In the meantime, the OECD Test Guidelines Programme has undertaken important steps to revise established and to develop new test methods, which can be used to identify and quantify effects of endocrine-disrupting chemicals on mammals, birds, amphibians, fish, and invertebrates. For fish testing of endocrine-disrupting chemicals, the first Test Guidelines have recently been adopted by the OECD and validation of further test systems is under progress. Based on these test systems and the experience gained during their validation procedures, we propose a 3-step fish testing strategy: 1) Weight-of-evidence approach for identifying potential sexual endocrine-disrupting chemicals; even after advanced specification of systematic criteria, this step of establishing initial suspicion will still require expert judgment; 2) in vivo evaluation of sexual endocrine-disrupting activity in fish by applying in vivo fish screening assays; sufficient data are available to diagnose the aromatase-inhibition and estrogen-receptor agonist mechanisms of action by indicative endpoints (biomarkers), whereas the ability of the respective biomarkers in the screening assay to identify the estrogen-receptor antagonists and androgen-receptor agonists and antagonists requires further validation; 3) characterization of sexual endocrine-mediated adverse effects including threshold concentrations; in cases when the most sensitive population-relevant endpoints and the most sensitive time window for exposure are known for the mechanisms of action, the fish full life-cycle or 2-generation test, which are the normal definitive tests, might be abbreviated to, e.g., the fish sexual development test. In the European Union, the measurement of indicative endpoints in the definitive test might be crucial for the authorization procedure under REACH and plant-protection products. The results of the definitive tests can be used in existing schemes of compound-specific environmental risk assessments. PMID:20872646

Knacker, Thomas; Boettcher, Melanie; Frische, Tobias; Rufli, Hans; Stolzenberg, Hans-Christian; Teigeler, Matthias; Zok, Sabine; Braunbeck, Thomas; Schäfers, Christoph

2010-10-01

198

Relationship between horizontal hydroacoustic stock estimates and gillnet catches of surface-oriented fish in shallow Lake Balaton (Hungary) Relation entre les estimations horizontales hydroacoustiques du stock et les captures au filet maillant de poissons de surface en eaux peu profondes du lac Balaton (Hongrie)  

Directory of Open Access Journals (Sweden)

Full Text Available We examined whether gillnetting and hydroacoustics provide comparable relative fish density and fish size distribution estimates in the uppermost water layer of a shallow turbid lake and whether the inclusion of environmental and stock parameters could improve comparability of data between different gears. According to gillnetting, most fish shorter than 14 cm in total length were Alburnus alburnus, and most fish longer than 14 cm were Pelecus cultratus. Size distributions and median sizes obtained from gillnetting and acoustics differed. Pure acoustics-derived density estimates accounted for only Nous avons examiné si les filets maillants et l’hydroacoustique fournissent des données comparables de la densité des poissons et des estimations de distribution en taille des poissons dans la couche d’eau supérieure d’un lac peu profond trouble et si l’inclusion de paramètres environnementaux et du stock de poissons pourrait améliorer la comparabilité des données entre les différents engins. Selon la pêche au filet maillant, la plupart des poissons de longueur totale inférieure à 14 cm étaient Alburnus alburnus, et la plupart des poissons de plus de 14 cm étaient Pelecus cultratus. Les distributions de taille et les tailles médianes obtenues à partir des filets maillants et de l’acoustique sont différentes. Les estimations dérivées de la seule densité acoustique ne représentaient que moins de 8,8?% de la variation des captures au filet maillant en nombre et aucune corrélation n’a été trouvée dans les indices de biomasse. La plupart des variations observées dans les captures par unité d’effort des filets maillants ont été associées à la transparence de l’eau, aucune des autres variables étudiées n’ont un important pouvoir explicatif. Nous concluons que la possibilité d’établir un modèle puissant décrivant la relation entre les estimations de la densité des poissons par pêche au filet maillant et de l’acoustique est faible dans les habitats peu profonds et troubles, et il ne pourrait être valable que si l’échantillonnage et les paramètres environnementaux affectant l’efficacité de capture des filets maillants et le post-traitement des données acoustiques sont considérés. Cette étude rappelle encore une fois que les filets maillants doivent être utilisés avec précaution pour analyser les tendances de l’abondance des poissons.

György Á.I.; Tátrai I.; Specziár A.

2012-01-01

199

DDT in fishes from four different Amazon sites: exposure assessment for breast feeding infants  

Energy Technology Data Exchange (ETDEWEB)

Concerning DDT in food, based on clinical observations as well as experimental animals, the annual Joint FAO/WHO Meetings on Pesticide Residues held in 2000 estimated a Provisional Tolerable Daily Intake (PTDI) for DDT in 0.01 mg/kg/day. Marien and Laflamme have proposed a Tolerable Daily Intake (TDI) for breast feedings infants of 5 x 10{sup -3} mg/kg/day, and conducted an assessment to evaluate the public health significance of eating {sigma}ODDT contaminated fish, accomplished by establishing a daily intake level of DDT for the population of greatest concern, like breastfeeding infants. Their results indicated that mothers who frequently consume contaminated fish could have breast milk DDT concentrations highly enough to expose their infants to levels above the TDI. The aim of this study was to evaluate the ODDT (o,p'-DDT + p,p'-DDT + o,p'-DDE + p,p'-DDE + o,p'-DDD) levels in commercial fish samples from distinct Brazilian Amazon sites, which are consumed by the riverine populations, and to assess the potential health impacts from eating these fishes, especially for breastfeeding infants.

D' Amato, C.; Torres, J.P.; Malm, O. [Lab. de Radioisotopos Eduardo Penna Franca, Inst. de Biofisica, UFRJ, RJ (Brazil); Bastos, W. [Lab. de Biogeoquimica, UNIR, Porto Velho (Brazil); Claudio, L.; Markowitz, S. [International Training Program on Environmental and Occupational Health, Mount Sinai School of Medicine, Queens Coll., NY (United States)

2004-09-15

200

Assessing the sensitivity of habitats to fishing: from seabed maps to sensitivity maps(a.).  

UK PubMed Central (United Kingdom)

In the Welsh part of the Irish Sea, a method was developed for assessing the sensitivity of different seabed habitats to existing fishing activities, across a range of potential fishing intensities. The resistance of 31 habitats and their associated biological assemblage to damage by 14 categories of fishing activity were assessed along with the rate at which each habitat would recover following impact (resilience). Sensitivity was scored based on a combination of the resistance of a habitat to damage and its subsequent rate of recovery. The assessments were based, wherever possible, on scientific literature, with expert judgement used to extrapolate results to habitat and gear combinations not directly examined in the published literature. The resulting sensitivity matrices were then subject to further peer review at a series of workshops. Following consensus on the habitat sensitivity, these data were combined with the most resolved sea-floor habitat maps. These habitat sensitivity maps can help inform the development of site-specific management plans, as well as having a place in spatial planning and aiding managers in developing dialogue with other stakeholders. A case study of their application is provided.

Eno NC; Frid CL; Hall K; Ramsay K; Sharp RA; Brazier DP; Hearn S; Dernie KM; Robinson KA; Paramor OA; Robinson LA

2013-10-01

 
 
 
 
201

Fish micronucleus assay to assess genotoxic potential of arsenic at its guideline exposure in aquatic environment.  

UK PubMed Central (United Kingdom)

The exposure to arsenic, a potential genotoxic carcinogen in humans, via drinking water is a serious worldwide health hazard. The arsenic content of 10 ?g L(-1) in drinking water, however, has been established as its guideline standard (maximum contaminant limit) that has been estimated to pose minimum risk to cancer. Since micronucleus induction in the erythrocytes of fish is a sensitive indicator of genotoxic agents in water, the piscine micronucleus assay was used in the present experiment to assess the genotoxic potential of arsenic at its various exposure levels including the guideline value for drinking water. The experiments were conducted in two different species of fishes, the pond murrel (Channa punctatus) and the goldfish (Carassius auratus). Significant increases in the frequency of micronucleated erythrocytes were documented in a dose-dependent manner in both Channa and Carassius. The fishes, however, exhibited variations in inter-specific sensitivity to micronucleus induction following arsenic exposure. The exposure level of arsenic at its guideline value for drinking water, therefore, exhibited marked genotoxicity in fishes.

Kumar A; Kesari VP; Khan PK

2013-04-01

202

Fish micronucleus assay to assess genotoxic potential of arsenic at its guideline exposure in aquatic environment.  

Science.gov (United States)

The exposure to arsenic, a potential genotoxic carcinogen in humans, via drinking water is a serious worldwide health hazard. The arsenic content of 10 ?g L(-1) in drinking water, however, has been established as its guideline standard (maximum contaminant limit) that has been estimated to pose minimum risk to cancer. Since micronucleus induction in the erythrocytes of fish is a sensitive indicator of genotoxic agents in water, the piscine micronucleus assay was used in the present experiment to assess the genotoxic potential of arsenic at its various exposure levels including the guideline value for drinking water. The experiments were conducted in two different species of fishes, the pond murrel (Channa punctatus) and the goldfish (Carassius auratus). Significant increases in the frequency of micronucleated erythrocytes were documented in a dose-dependent manner in both Channa and Carassius. The fishes, however, exhibited variations in inter-specific sensitivity to micronucleus induction following arsenic exposure. The exposure level of arsenic at its guideline value for drinking water, therefore, exhibited marked genotoxicity in fishes. PMID:23494554

Kumar, Amod; Kesari, Vibudh P; Khan, Parimal K

2013-03-14

203

ASSESSING HEAVY METALS IN THE WATERS, FISH AND MACROINVERTEBRATES IN MANILA BAY, PHILIPPINES  

Directory of Open Access Journals (Sweden)

Full Text Available This study assessed the heavy metals particularly total cadmium, total lead and total chromium in the waters, fish and macroinvertebrates in Manila Bay, Philippines. The heavy metals monitoring in the waters of Manila Bay were carried out for six consecutive months, September to February of 2007-2008, covering both wet and dry periods. The collection of fishes and macroinvertebrates in this investigation lasted from September to November 2007. Results showed that the heavy metals particularly total chromium, total lead and total cadmium were evident in the waters, fish and macroinvertebrates. Significant differences on the total cadmium and total lead in the waters were noted for both the wet and dry periods. Accumulation of heavy metals in the aquatic organisms was species dependent. Highest heavy metal concentrations among the tissues in the studied fishes were evident in the liver as compared to the muscle. Continuous heavy metals monitoring is encouraged to effectively analyze the risk and impact of heavy metals on the environment and on the general public’s welfare.

GLENN SIA SU; KRISTINE JOY MARTILLANO; TESSA PAULA ALCANTARA; ELENA RAGRAGIO; JOSEFINA DE JESUS; ARNOLD HALLARE; GLICERIA RAMOS

2009-01-01

204

Effects of a toxic cyanobacterial bloom (Planktothrix agardhii) on fish: insights from histopathological and quantitative proteomic assessments following the oral exposure of medaka fish (Oryzias latipes).  

UK PubMed Central (United Kingdom)

Cyanobacterial toxic blooms often occur in freshwater lakes and constitute a potential health risk to human populations, as well as to fish and other aquatic organisms. Microcystin-LR (the cyanotoxin most commonly detected in the freshwater environment) is a potent hepatotoxin, deregulating the kinase pathway by inhibiting phosphatases 1 and 2A. Although toxicological effects have been clearly linked to the in vitro exposure of fish to purified microcystins, cyanotoxins are produced by the cyanobacteria together with numerous other potentially toxic molecules, and their overall and specific implications for the health of fish have still not been clearly established and remain puzzlingly difficult to assess. The medaka fish (Oryzias latipes) was chosen as an in vitro model for studying the effects of a cyanobacterial bloom on liver protein contents using a gel free quantitative approach, iTRAQ, in addition to pathology examinations on histological preparations. Fish were gavaged with 5 ?L cyanobacterial extracts (Planktothrix agardhii) from a natural bloom (La Grande Paroisse, France) containing 2.5 ?g equiv. MC-LR. 2h after exposure, the fish were sacrificed and livers were collected for analysis. Histological observations indicate that hepatocytes present glycogen storage loss, and cellular damages, together with immunological localization of MCs. Using a proteomic approach, 304 proteins were identified in the fish livers, 147 of them with a high degree of identification confidence. Fifteen of these proteins were statistically significantly different from those of controls (gavaged with water only). Overall, these protein regulation discrepancies clearly indicate that oxidative stress and lipid regulation had occurred in the livers of the exposed medaka fish. In contrast to previous pure microcystin-LR gavage experiments, marked induction of vitellogenin 1 protein was observed for the first time with a cyanobacterial extract. This finding was confirmed by ELISA quantification of vitellogenin liver content, suggesting that the Planktothrix bloom extract had induced the occurrence of an endocrine-disrupting effect.

Marie B; Huet H; Marie A; Djediat C; Puiseux-Dao S; Catherine A; Trinchet I; Edery M

2012-06-01

205

Effects of a toxic cyanobacterial bloom (Planktothrix agardhii) on fish: insights from histopathological and quantitative proteomic assessments following the oral exposure of medaka fish (Oryzias latipes).  

Science.gov (United States)

Cyanobacterial toxic blooms often occur in freshwater lakes and constitute a potential health risk to human populations, as well as to fish and other aquatic organisms. Microcystin-LR (the cyanotoxin most commonly detected in the freshwater environment) is a potent hepatotoxin, deregulating the kinase pathway by inhibiting phosphatases 1 and 2A. Although toxicological effects have been clearly linked to the in vitro exposure of fish to purified microcystins, cyanotoxins are produced by the cyanobacteria together with numerous other potentially toxic molecules, and their overall and specific implications for the health of fish have still not been clearly established and remain puzzlingly difficult to assess. The medaka fish (Oryzias latipes) was chosen as an in vitro model for studying the effects of a cyanobacterial bloom on liver protein contents using a gel free quantitative approach, iTRAQ, in addition to pathology examinations on histological preparations. Fish were gavaged with 5 ?L cyanobacterial extracts (Planktothrix agardhii) from a natural bloom (La Grande Paroisse, France) containing 2.5 ?g equiv. MC-LR. 2h after exposure, the fish were sacrificed and livers were collected for analysis. Histological observations indicate that hepatocytes present glycogen storage loss, and cellular damages, together with immunological localization of MCs. Using a proteomic approach, 304 proteins were identified in the fish livers, 147 of them with a high degree of identification confidence. Fifteen of these proteins were statistically significantly different from those of controls (gavaged with water only). Overall, these protein regulation discrepancies clearly indicate that oxidative stress and lipid regulation had occurred in the livers of the exposed medaka fish. In contrast to previous pure microcystin-LR gavage experiments, marked induction of vitellogenin 1 protein was observed for the first time with a cyanobacterial extract. This finding was confirmed by ELISA quantification of vitellogenin liver content, suggesting that the Planktothrix bloom extract had induced the occurrence of an endocrine-disrupting effect. PMID:22414781

Marie, Benjamin; Huet, Hélène; Marie, Arul; Djediat, Chakib; Puiseux-Dao, Simone; Catherine, Arnaud; Trinchet, Isabelle; Edery, Marc

2012-02-17

206

Ecological risk assessment of substances with suspected estrogenic activity using standard laboratory fish tests  

Energy Technology Data Exchange (ETDEWEB)

The assessment of risks to the aquatic environment in the European Union is generally based on a comparison of Predicted Environmental Concentrations (PEC) with Predicted No Effect Concentrations (PNEC) for surrogate, or representative, organisms of the receiving waters. Such risk assessments are required for new and priority existing chemicals, pesticides, and, in the near future, biocides; they are dependent on robust in vivo test data. Current strategies for ecological risk assessment were not designed to assess the risk of endocrine disrupters. The selection of suitable fish species and practical in vivo end points for determining endocrine disruption in fish are discussed, including the adaptation of some existing guidelines. This paper is partly based on a series of experiments conducted at the laboratory to look at the effects of a model alkylphenol (4-tert-pentylphenol), an industrial chemical intermediate, acting as a pseudo-estrogen on an all-male population of the common carp, Cyprinus carpio. Exposure to the test substance occurred at critical life stages for endocrine disruption. Biochemical parameters as well as histological parameters were applied, and their suitability to be used in ecological risk assessment is discussed.

Gimeno, S.; Bowmer, C.T.

1999-07-01

207

Submission of Danish Coastal Fish data to HELCOM FISH, for the Thematic Assessment : Data from six NOVANA stations 2006  

DEFF Research Database (Denmark)

Coastal fish communities are important components of Baltic Sea ecosystems. Coastal fish experts have been meeting on an annual basis since 2004 under the umbrella of HELCOM. In 2006, the expert group developed a metadatabase on monitoring activities, methods, parameters and species surveyed based on the data contained in the COBRA database. A GIS interactive map was subsequently created by HELCOM to improve access to the information in the metadatabase and to visualise coastal fish monitoring activities in the Baltic Sea. Link: http://www.helcom.fi/GIS/en_GB/coastalfishGIS/

Strand, Jakob

208

Assessment of Present Anadromous Fish Production Facilities in the Columbia River Basin, US Fish and Wildlife Hatcheries, Final Report.  

Energy Technology Data Exchange (ETDEWEB)

The goal of this report is to document current production practices for hatcheries which rear anadromous fish in the Columbia River Basin and to identify those facilities where production can be increased. A total of 85 hatchery and satellite facilities operated by the Idaho Department of Fish and Game, Oregon Department of Fish and Game, US Fish and Wildlife Service, Washington Department of Wildlife, and Washington Department of Fisheries were evaluated. The years 1985 to 1987 were used in this evaluation. During those years, releases averaged 143,306,596 smolts weighing 7,693,589 pounds. A total of 48 hatchery or satellite facilities were identified as having expansion capability. They were estimated to have the potential for increasing production by an 84,448,000 smolts weighing 4,853,306 pounds. 2 refs., 25 tabs.

Delarm, Michael R.; Smith, Robert Z.

1990-07-01

209

Assessment of Present Anadromous Fish Production Facilities in the Columbia River Basin, Washington Department of Fish Hatcheries, Final Report.  

Energy Technology Data Exchange (ETDEWEB)

The goal of this report is to document current production practices for hatcheries which rear anadromous fish in the Columbia River Basin and to identify those facilities where production can be increased. A total of 85 hatchery and satellite facilities operated by the Idaho Department of Fish and Game, Oregon Department of Fish and Game, US Fish and Wildlife Service, Washington Department of Wildlife, and Washington Department of Fisheries were evaluated. The years 1985 to 1987 were used in this evaluation. During those years, releases averaged 143,306,596 smolts weighing 7,693,589 pounds. A total of 48 hatchery or satellite facilities were identified as having expansion capability. They were estimated to have the potential for increasing production by an 84,448,000 smolts weighing 4,853,306 pounds. 2 refs., 25 figs.

Delarm, Michael R.; Smith, Robert Z.

1990-07-01

210

A review of image-based tools for automatic fish ageing from otolith features  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Most of European fish stocks are assessed using age-based models, and otolith interpretation for age estimations costs several million euros annually. In this context, automated ageing systems would provide a mean to 1) standardize ageing, 2) control ageing consistency within and between ageing labo...

Carbini, Sebastien; Chessel, Anatole; Benzinou, Abdesslam; Fablet, Ronan; Mahe, Kelig; De Pontual, Helene

211

A multivariate indicator to monitor changes in spatial patterns of age-structured fish populations  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Quantitative analysis of the spatial patterns in age-structured fish populations provides a useful complement to stock assessment methods. The spatial distribution of an age-structured population is characterized by indicators for location, dispersion and aggregation, which are estimated from survey...

Petitgas Pierre; Poulard Jean-charles

212

Application of sensory and microbial analysis to assess quality of fish in Siliguri city of West Bengal, India.  

UK PubMed Central (United Kingdom)

Sensory and certain microbial analyses were applied to assess the quality of raw fish sold at a market in Siliguri cityof West Bengal, India. In regular surveys undertaken during June to August 2008, a particular fish species was randomly selected, its source was noted and a sensory analysis, the quality index method (QIM) was applied to assess its quality Raw fish samples were also collected and a small quantity (about 1 g) of scales oran upper layer of the skin surface (forscale-less fish samples), gill, liverand a portion of gut with gut-contents were aseptically removed for enumeration of the total aerobic heterotrophic bacteria, Aeromonas spp., Pseudomonas spp., Salmonella spp. and coliform counts. Oreochromis mossambicus and Tenulosa ilisha recorded significantly higher QIM scores, compared to other species (p<0.05). Riverine fish, Lepidocephalichthys guntea and Channa punctatus scored the lowest QIM scores (0) while scores for Puntius ticto and Mystus vittatus and pond cultured species like Cirrhinus mrigala, Catla catla, Labeo rohita, Labeo bata and Cyprinus carpio were very marginal (p<0.05). Aeromonas spp., Salmonella spp. and total coliforms were recorded from all the studied species while Pseudomonas spp. was isolated from only seven species. Among the tissues examined, the lowest counts of total heterotrophic bacteria, Aeromonas spp., Pseudomonas spp., Salmonella spp. and total coliforms were recorded from the skin in every fish species. Highest counts of pathogenic bacteria (except Pseudomonas spp.) were recorded in Tenulosa ilisha for all the tissues except liver. Since fish are properly cooked in Bengali households, the risk of disease from fish consumption is relatively less. However, some tribes residing in the region are known to consume undercooked fish and proper cooking methods should be followed in view of the present findings to avoid health risks. Besides, utmost care should be taken while handling fish.

Jha P; Roy RP; Barat S

2010-09-01

213

Comparative toxicology for risk assessment of marine fishes and crustaceans. [Cyprinodon variegatus  

Energy Technology Data Exchange (ETDEWEB)

The goal of this study was to collect data on the effects of chemicals on marine fishes and crustaceans and to evaluate the predictive power of the data for assessing risks to marine resources. The data sets consisted of acute median lethal concentrations (LC{sub 50s}) and chronic maximum acceptable toxicant concentrations (MATCs). They were analyzed with regression models and simple comparisons. The conclusions include the following: (1) the variability found in the marine data was comparable to that found in freshwater data; (2) the standard marine test fish Cyprinodon variegatus appears to be representative of marine fishes; (3) the responses of marine crustaceans are so highly diverse that the concept of a representative crustacean is questionable; (4) mysid and penaeid shrimp appear to be particularly sensitive to toxic chemicals. These conclusions are subject to the constraints of the existing limited data base and should be confirmed by a systematic study of the relative sensitivity of marine organisms to chemicals with diverse modes of action.

Suter, G.W. II; Rosen, A.E. (Oak Ridge National Lab., TN (USA))

1988-05-01

214

First record of Chilodonella hexasticha (Ciliophora: Chilodonellidae) in Brazilian cultured fish: a morphological and pathological assessment.  

UK PubMed Central (United Kingdom)

Chilodonelids are small ciliated protozoans found worldwide and can be dangerous in culture conditions. This study presents morphometric data on the ciliate Chilodonella that is found in cultured Nile tilapia (Oreochromis niloticus), native bait fish tuvira (Gymnotus aff. inaequilabiatus) and native pacu (Piaractus mesopotamicus) and includes a histopathological assessment of the changes that occur in the pacu. For parasitic diagnosis, skin and gill samples were scraped onto slides, dried at room temperature, stained with Giemsa or impregnated with silver nitrate, and the measurements were obtained from photomicrographs. In the diseased pacu, the first gill arch was collected and fixed in a 10% buffered formalin solution for histopathological analysis. Parasite specimens from the different collection sites were identified morphologically as C. hexasticha Kiernik (1909). Diseased fish exhibited depigmentation, skin ulceration, scale loss, excessive mucus production and gill lesions. Histopathological analysis of pacu gills displayed epithelial proliferation with mononuclear inflammatory infiltrate, hemorrhages, and scattering necrosis. In Brazilian-farmed fish this is the first record of C. hexasticha, which has great pathogenic potential in cultured freshwater species. In addition, two new hosts are presented.

Pádua SB; Martins ML; Carrijo-Mauad JR; Ishikawa MM; Jerônimo GT; Dias-Neto J; Pilarski F

2013-01-01

215

Growth history and intrinsic factors influence risk assessment at a critical life transition for a fish  

Science.gov (United States)

Making the appropriate decision in the face of predation risk dictates the fate of prey, and predation risk is highest at life history boundaries such as settlement. At the end of the larval phase, most coral reef fishes enter patches of reef containing novel predators. Since vision is often obscured in the complex surroundings, chemical information released from damaged conspecific is used to forewarn prey of an active predator. However, larvae enter the reef environment with their own feeding and growth histories, which will influence their motivation to feed and take risks. The present study explored the link between recent growth, feeding history, current performance and behavioural risk taking in newly settling stages of a coral reef damselfish ( Pomacentrus amboinensis). Older and larger juveniles in good body condition had a stronger response to chemical alarm cues of injured conspecifics; these fish spent a longer time in shelter and displayed a more dramatic decrease in foraging behaviour than fish in lower body condition. Feeding experiments supported these findings and emphasized the importance of body condition in affecting risk assessment. Evidently, larval growth history and body condition influences the likelihood of taking risks under the threat of predation immediately after settlement, thereby affecting the probability of survival in P. amboinensis.

Lönnstedt, O. M.; McCormick, M. I.

2011-09-01

216

Risk and toxicity assessments of heavy metals in sediments and fishes from the Yangtze River and Taihu Lake, China.  

UK PubMed Central (United Kingdom)

Heavy metal pollution is one of the most serous environmental issues globally. To evaluate the metal pollution in Jiangsu Province of China, the total concentrations of heavy metals in sediments and fishes from the Yangtze River and Taihu Lake were analyzed. Ecological risk of sediments and human health risk of fish consumption were assessed respectively. Furthermore, toxicity of samples on expression of the stress responsive genes was evaluated using microbial live cell-array method. The results showed that the heavy metals concentrations in sediments from the Yangtze River were much higher than those in sediments from the Taihu Lake. However, the fishes from the Taihu Lake had higher concentrations of heavy metals than fishes from the Yangtze River. Ecological risk evaluation showed that the heavy metal contaminants in sediments from the Yangtze River posed higher risk of adverse ecological effects, while sediments from the study areas of Taihu Lake were relatively safe. Health risk assessment suggested that the heavy metals in fishes of both Yangtze River and Taihu Lake might have risk of adverse health effects to human. The toxicity assessment indicated that the heavy metals in these sediments and fishes showed transcriptional effects on the selected 21 stress responsive genes, which were involved in the pathways of DNA damage response, chemical stress, and perturbations of electron transport. Together, this field investigation combined with chemical analysis, risk assessment and toxicity bioassay would provide useful information on the heavy metal pollution in Jiangsu Province.

Fu J; Hu X; Tao X; Yu H; Zhang X

2013-07-01

217

Screening level fish community risk assessment of chemical warfare agents in the Baltic Sea.  

UK PubMed Central (United Kingdom)

Chemical warfare agents (CWAs) have been disposed of in various fashions over the past decades. Significant amounts (approximately 11,000 tonnes) have been dumped in the Baltic Sea east of the island Bornholm following the disarmament of Germany after World War II, causing concerns over potential environmental risks. Absence of risk based on assumptions of extremely low solubility of CWAs cannot alone dismiss these concerns. Existing and modelled fate and effects data were used in the analysis to assess the fish community risk level. The most realistic and also conservative assessment result is the scenario describing 70 m water depth for the most realistic dump-site area with a focus on chronic toxicity, at 0-20 cm above the sediment, yielding a total mixture toxic unit (TU) of 0.62. Triphenylarsine is the CWA with the highest realistic risk profile at 0.2 TU for the fish community followed by Adamsite (0.17), Clark I (0.086) and Yperite (0.083) TU. Adamsite is more persistent and constitutes a potential risk for a longer period than triphenylarsine. The seawater volume potentially at risk is <4 m above sediment and <58 km down current of dump sites. Further risk assessment of dumped CWAs in the Baltic Sea is warranted.

Sanderson H; Fauser P; Thomsen M; Sørensen PB

2008-06-01

218

Screening level fish community risk assessment of chemical warfare agents in the Baltic Sea.  

Science.gov (United States)

Chemical warfare agents (CWAs) have been disposed of in various fashions over the past decades. Significant amounts (approximately 11,000 tonnes) have been dumped in the Baltic Sea east of the island Bornholm following the disarmament of Germany after World War II, causing concerns over potential environmental risks. Absence of risk based on assumptions of extremely low solubility of CWAs cannot alone dismiss these concerns. Existing and modelled fate and effects data were used in the analysis to assess the fish community risk level. The most realistic and also conservative assessment result is the scenario describing 70 m water depth for the most realistic dump-site area with a focus on chronic toxicity, at 0-20 cm above the sediment, yielding a total mixture toxic unit (TU) of 0.62. Triphenylarsine is the CWA with the highest realistic risk profile at 0.2 TU for the fish community followed by Adamsite (0.17), Clark I (0.086) and Yperite (0.083) TU. Adamsite is more persistent and constitutes a potential risk for a longer period than triphenylarsine. The seawater volume potentially at risk is <4 m above sediment and <58 km down current of dump sites. Further risk assessment of dumped CWAs in the Baltic Sea is warranted. PMID:18079057

Sanderson, Hans; Fauser, Patrik; Thomsen, Marianne; Sørensen, Peter B

2007-11-09

219

Assessing the feasibility of native fish reintroductions: a framework applied to threatened bull trout  

Science.gov (United States)

Translocations to recover native fishes have resulted in mixed success. One reason for the failure of these actions is inadequate assessments of their feasibility prior to implementation. Here, we provide a framework developed to assess the feasibility of one type of translocation-reintroduction. The framework was founded on two simple components of feasibility: the potential for recipient habitats to support a reintroduction and the potential of available donor populations to support a reintroduction. Within each component, we developed a series of key questions. The final assessment was based on a scoring system that incorporated consideration of uncertainty in available information. The result was a simple yet transparent system for assessing reintroduction feasibility that can be rapidly applied in practice. We applied this assessment framework to the potential reintroduction of threatened bull trout Salvelinus confluentus into the Clackamas River, Oregon. In this case, the assessment suggested that the degree of feasibility for reintroduction was high based on the potential of recipient habitats and available donor populations. The assessment did not provide a comprehensive treatment of all possible factors that would drive an actual decision to implement a reintroduction,

Dunham, Jason; Gallo, Kirsten; Shively, Dan; Allen, Chris; Goehring, Brad

2011-01-01

220

A Multiple Watershed Approach to Assessing the Effects of Habitat Restoration Actions on Anadromous and Resident Fish Populations, Technical Report 2003-2004.  

Energy Technology Data Exchange (ETDEWEB)

Habitat protection and restoration is a cornerstone of current strategies to restore ecosystems, recover endangered fish species, and rebuild fish stocks within the Columbia River Basin. Strategies featuring habitat restoration include the 2000 Biological Opinion on operation of the Federal Columbia River Power System (FCRPS BiOp) developed by the National Marine Fisheries Service (NMFS), the 2000 Biological Opinion on Bull Trout developed by the US Fish and Wildlife Service (USFWS), and Sub-Basin Plans developed under the Fish and Wildlife Program of the Northwest Power and Conservation Council (NWPCC). There is however little quantitative information about the effectiveness of different habitat restoration techniques. Such information is crucial for helping scientists and program managers allocate limited funds towards the greatest benefits for fish populations. Therefore, it is critical to systematically test the hypotheses underlying habitat restoration actions for both anadromous and resident fish populations. This pilot project was developed through a proposal to the Innovative Projects fund of the NWPCC (ESSA 2002). It was funded by the Bonneville Power Administration (BPA) following reviews by the Independent Scientific Review Panel (ISRP 2002), the Columbia Basin Fish and Wildlife Authority (CBFWA 2002), the NWPCC and BPA. The study was designed to respond directly to the above described needs for information on the effectiveness of habitat restoration actions, including legal measures specified in the 2000 FCRPS BiOp (RPA 183, pg. 9-133, NMFS 2000). Due to the urgency of addressing these measures, the timeline of the project was accelerated from a duration of 18 months to 14 months. The purpose of this pilot project was to explore methods for evaluating past habitat restoration actions and their effects on fish populations. By doing so, the project will provide a foundation of retrospective analyses, on which to build prospective, multi-watershed designs for future habitat restoration actions. Such designs are being developed concurrently with this project by several other groups in the Columbia Basin (RME Workgroup 2003, NMFS 2003, Hillman and Paulsen 2002, Hillman 2003). By addressing questions about habitat restoration and monitoring (in coordination with other related efforts), we hope that this project will catalyze a shift in the Basin's paradigm of habitat restoration, moving from implementation of individual watershed projects towards rigorously designed and monitored, multiwatershed, adaptive management experiments. The project involved three phases of work, which were closely integrated with various related and ongoing efforts in the region: (1) Scoping - We met with a Core Group of habitat experts and managers to scope out a set of testable habitat restoration hypotheses, identify candidate watersheds and recommend participants for a data evaluation workshop. (2) Data Assembly - We contacted over 80 scientists and managers to help evaluate the suitability of each candidate watershed's historical data for assessing the effectiveness of past restoration actions. We eventually settled on the Yakima, Wenatchee, Clearwater, and Salmon subbasins, and began gathering relevant data for these watersheds at a workshop with habitat experts and managers. Data assembly continued for several months after the workshop. (3) Data Analysis and Synthesis - We explored statistical approaches towards retrospectively analyzing the effects of restoration 'treatments' at nested spatial scales across multiple watersheds (Chapters 2-5 of this report). These analyses provided a foundation for identifying existing constraints to testing restoration hypotheses, and opportunities to overcome these constraints through improved experimental designs, monitoring protocols and project selection strategies (Chapters 6 and 7 of this report). Finally, we developed a set of recommendations to improve the design, implementation, and monitoring of prospective habitat restoration programs in the Columbia River Basin (Chap

Marmorek, David

2004-03-01

 
 
 
 
221

Does predation by grey seals (Halichoerus grypus) affect Bothnian Sea herring stock estimates?  

DEFF Research Database (Denmark)

Mortality of small pelagic fish due to marine mammals is generally considered to be low compared with other sources of mortality. With recent recoveries of marine mammal predators worldwide, this may no longer hold. The grey seal (Halichoerus grypus) population in the Bothnian Sea has increased fivefold since 1985. Its main prey, herring (Clupea harrengus), is a key species for fisheries in the region. Yet, current stock assessments assume constant natural mortality, leading to a risk of biased stock estimates with increasing predation and misleading analyses of herring population dynamics. We estimated grey seal predation from diet data and reanalysed herring spawning stock biomass (SSB) during 1973–2009. Accounting for predation increased the herring SSB 16% (maximum 19%), but this was within the confidence intervals when ignoring predation. Although mortality in older individuals was inflated when accounting for seal predation, this did not change the conclusions about drivers of herring dynamics. Accounting for grey seal predation is important for abundance estimates of old herring, but currently not for SSB estimates, given the great uncertainties in the standard assessment. The grey seal impact on Bothnian Sea herring will need to be reassessed if stock age composition, grey seal feeding preferences, or total stock development change

Gårdmark, Anna; Östman, Örjan

2012-01-01

222

Biological assessments of Appalachian streams based on predictive models for fish, macroinvertebrate, and diatom assemblages  

Science.gov (United States)

We developed empirical models for fish, macroinvertebrate, and diatom assemblages to assess the biological condition of 268 streams sampled from 1993 to 2002 in 7 major river basins in the Appalachian region of the USA. These models estimate the expected taxonomic composition at each site based on observed variation in taxonomic composition at reference sites. The index, O/E, is the ratio of the number of predicted taxa that were observed (O) to that expected (E) to occur at a site and is a measure of taxonomic completeness. We compared how O/E for each assemblage varied among major landuse settings and whether impaired assemblages were associated with particular physicochemical conditions. We also examined concordance among assemblages in their response to stress. Biological, chemical, and physical data were collected following consistent protocols. We used land-cover criteria, published data, and topographic maps to classify sites by major landuse setting. Fish, macroinvertebrate, and diatom assemblages had been sampled at 73, 108, and 52, respectively, of the least disturbed sites used to establish reference conditions. The models accounted for a substantial portion of the natural variation in taxonomic composition across sites that was associated with biogeographic, climatic, and basin-scale factors and generally were unbiased across the range of environmental gradients observed in the region. Assessments at nonreference sites showed that impairment of fish and macroinvertebrate assemblages was most strongly associated with agriculture and urban land uses, whereas impairment of diatom assemblages was most strongly associated with mining in the basin. Concordance in assessments among assemblages was not strong. Assessments based on 2 assemblages differed in 28 to 57% of cases, and assessments were never concordant for cases where all 3 assemblages were sampled. Furthermore, only 1/2 of these cases would have been assessed as ecologically impaired had only 1 assemblage been sampled. Differences between observed and predicted frequencies of occurrence for individual taxa were generally consistent with known tolerances to environmental stressors and might aid in identifying causes of biological impairment. ?? 2008 by The North American Benthological Society.

Carlisle, D. M.; Hawkins, C. P.; Meador, M. R.; Potapova, M.; Falcone, J.

2008-01-01

223

Risk assessment of dietary exposure to methylmercury in fish in the UK.  

UK PubMed Central (United Kingdom)

Risk assessment of chemicals in food is generally based upon the results of toxicological studies in laboratory animals, allowing for uncertainties relating to interspecies differences, human variability, and gaps in the database. Use of quantitative human data is preferable if available, as in the example of methylmercury. Methylmercury is a neurotoxic environmental contaminant, for which fish is the main source of dietary exposure. Human data from poisoning incidents and epidemiological studies have been used by expert committees to derive a guideline intake level for methylmercury, based on the susceptibility of the most sensitive lifestage, the developing fetus. In the UK, an expert group of nutritionists and toxicologists was formed to review the benefits and risks associated with fish consumption. A formal risk-benefit analysis was not possible because the nutritional data were not sufficiently quantitative. The Committee on Toxicity of Chemicals in Food, Consumer Products and the Environment (COT), therefore, modified the risk assessment approach to derive different guideline intake levels for different subgroups of the population. The COT opinion was used to provide targeted advice on how much fish can be consumed without undue risk from the contaminants. Consumption by adults of one weekly portion (140 g) of shark, swordfish or marlin, would lead to an exceedance of the guideline intake for methylmercury of 40-90%, set to protect the developing fetus, without considering intake from the rest of the diet. Pregnant women and women who may become pregnant within 1 year were, therefore, advised to avoid consumption of these species. Intakes in other adults would be within a higher guideline intake, set to protect groups of the population other than the developing fetus. However, consumption by children of one weekly portion of these species could lead to an exceedance of this guideline intake by up to 60%, without considering intake from the rest of the diet. It was, therefore, advised that consumption of these species by children should be avoided.

Maycock BJ; Benford DJ

2007-03-01

224

Risk assessment of dietary exposure to methylmercury in fish in the UK.  

Science.gov (United States)

Risk assessment of chemicals in food is generally based upon the results of toxicological studies in laboratory animals, allowing for uncertainties relating to interspecies differences, human variability, and gaps in the database. Use of quantitative human data is preferable if available, as in the example of methylmercury. Methylmercury is a neurotoxic environmental contaminant, for which fish is the main source of dietary exposure. Human data from poisoning incidents and epidemiological studies have been used by expert committees to derive a guideline intake level for methylmercury, based on the susceptibility of the most sensitive lifestage, the developing fetus. In the UK, an expert group of nutritionists and toxicologists was formed to review the benefits and risks associated with fish consumption. A formal risk-benefit analysis was not possible because the nutritional data were not sufficiently quantitative. The Committee on Toxicity of Chemicals in Food, Consumer Products and the Environment (COT), therefore, modified the risk assessment approach to derive different guideline intake levels for different subgroups of the population. The COT opinion was used to provide targeted advice on how much fish can be consumed without undue risk from the contaminants. Consumption by adults of one weekly portion (140 g) of shark, swordfish or marlin, would lead to an exceedance of the guideline intake for methylmercury of 40-90%, set to protect the developing fetus, without considering intake from the rest of the diet. Pregnant women and women who may become pregnant within 1 year were, therefore, advised to avoid consumption of these species. Intakes in other adults would be within a higher guideline intake, set to protect groups of the population other than the developing fetus. However, consumption by children of one weekly portion of these species could lead to an exceedance of this guideline intake by up to 60%, without considering intake from the rest of the diet. It was, therefore, advised that consumption of these species by children should be avoided. PMID:17439921

Maycock, B J; Benford, D J

2007-03-01

225

Estimating the Worldwide Extent of Illegal Fishing  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Illegal and unreported fishing contributes to overexploitation of fish stocks and is a hindrance to the recovery of fish populations and ecosystems. This study is the first to undertake a world-wide analysis of illegal and unreported fishing. Reviewing the situation in 54 countries and on the high s...

Agnew, David J.; Pearce, John; Pramod, Ganapathiraju; Peatman, Tom; Watson, Reg; Beddington, John R.; Pitcher, Tony J.

226

Application of sensory and microbial analysis to assess quality of fish in Siliguri city of West Bengal, India.  

Science.gov (United States)

Sensory and certain microbial analyses were applied to assess the quality of raw fish sold at a market in Siliguri cityof West Bengal, India. In regular surveys undertaken during June to August 2008, a particular fish species was randomly selected, its source was noted and a sensory analysis, the quality index method (QIM) was applied to assess its quality Raw fish samples were also collected and a small quantity (about 1 g) of scales oran upper layer of the skin surface (forscale-less fish samples), gill, liverand a portion of gut with gut-contents were aseptically removed for enumeration of the total aerobic heterotrophic bacteria, Aeromonas spp., Pseudomonas spp., Salmonella spp. and coliform counts. Oreochromis mossambicus and Tenulosa ilisha recorded significantly higher QIM scores, compared to other species (pPuntius ticto and Mystus vittatus and pond cultured species like Cirrhinus mrigala, Catla catla, Labeo rohita, Labeo bata and Cyprinus carpio were very marginal (p<0.05). Aeromonas spp., Salmonella spp. and total coliforms were recorded from all the studied species while Pseudomonas spp. was isolated from only seven species. Among the tissues examined, the lowest counts of total heterotrophic bacteria, Aeromonas spp., Pseudomonas spp., Salmonella spp. and total coliforms were recorded from the skin in every fish species. Highest counts of pathogenic bacteria (except Pseudomonas spp.) were recorded in Tenulosa ilisha for all the tissues except liver. Since fish are properly cooked in Bengali households, the risk of disease from fish consumption is relatively less. However, some tribes residing in the region are known to consume undercooked fish and proper cooking methods should be followed in view of the present findings to avoid health risks. Besides, utmost care should be taken while handling fish. PMID:21387907

Jha, Prithwiraj; Roy, Rudra Prasad; Barat, S

2010-09-01

227

Carbon stock assessment for a forest-to-coffee conversion landscape in Sumber-Jaya (Lampung, Indonesia): from allometric equations to land use change analysis  

Energy Technology Data Exchange (ETDEWEB)

The change in stored carbon (C) stocks was assessed for a 700 km{sup 2} area where forest cover decreased from 60% to 10% in the last 30 years. At the same time, the area under coffee increased from 7% to 70% with a gradual evolution from open 'sun coffee' systems to multi-strata 'shade coffee' systems that provide a partial compensation for C loss. The use of a generic tropical forest rather than tree-specific allometric equation can lead to substantial (up to 100%) overestimates of aboveground biomass depending on wood density and tree shape. In the 1970 1984 period, while forest cover was reduced from 59.5% to 19.7%, the landscape lost on average 6.8 Mg C ha{sup -1} a{sup -1}. In the 1984 2000 period forest cover was further reduced to 12.6%, but the landscape lost only 0.39 Mg C ha{sup -1} a{sup -1}, as forest loss was partially compensated by an increase in shade coffee systems. Conversion of all current sun coffee to shade coffee systems while protecting the remaining forest, could increase average landscape level C stocks by 10 Mg ha{sup -1} over a time frame of say 20 years, or 0.5 Mg C ha{sup -1} a{sup -1}.

Meine van Noordwijk; Subekti Rahayu; Kurniatun Hairiah; Y.C. Wulan; A. Farida; Bruno Verbist [International Centre for Research in Agroforestry (ICRAF) SE Asia, Bogor (Indonesia)

2002-07-01

228

Arsenic concentration in rice, fish, meat and vegetables in Cambodia: a preliminary risk assessment.  

UK PubMed Central (United Kingdom)

To assess arsenic contaminations and its possible adverse health effects, food samples were collected from Kandal, Kratie and Kampong Cham in Cambodia. The highest and the lowest concentrations were observed in fish (mean 2,832 ng g(-1), ww) collected from Kandal province and cattle stomach (1.86 ± 1.10 ng g(-1), ww) collected from Kratie, respectively. The daily intake of arsenic via food consumption was 604, 9.70 and 136 ?g day(-1) in Kandal, Kratie and Kampong Cham, respectively. The arsenic dietary intake in Kandal ranked No. 1 among all the 17 compared countries or regions. Fish consumption contributed the greatest proportion of total arsenic daily intake in Kandal (about 63.0 %) and Kampong Cham (about 69.8 %). It is revealed to be a much more important exposure pathway than drinking water for residents in Kampong Cham. The results of risk assessment suggested that the residents in Cambodia, particularly for people in Kandal province, suffer high public health risks due to consuming arsenic-contaminated food.

Wang HS; Sthiannopkao S; Chen ZJ; Man YB; Du J; Xing GH; Kim KW; Mohamed Yasin MS; Hashim JH; Wong MH

2013-12-01

229

Arsenic concentration in rice, fish, meat and vegetables in Cambodia: a preliminary risk assessment.  

Science.gov (United States)

To assess arsenic contaminations and its possible adverse health effects, food samples were collected from Kandal, Kratie and Kampong Cham in Cambodia. The highest and the lowest concentrations were observed in fish (mean 2,832 ng g(-1), ww) collected from Kandal province and cattle stomach (1.86 ± 1.10 ng g(-1), ww) collected from Kratie, respectively. The daily intake of arsenic via food consumption was 604, 9.70 and 136 ?g day(-1) in Kandal, Kratie and Kampong Cham, respectively. The arsenic dietary intake in Kandal ranked No. 1 among all the 17 compared countries or regions. Fish consumption contributed the greatest proportion of total arsenic daily intake in Kandal (about 63.0 %) and Kampong Cham (about 69.8 %). It is revealed to be a much more important exposure pathway than drinking water for residents in Kampong Cham. The results of risk assessment suggested that the residents in Cambodia, particularly for people in Kandal province, suffer high public health risks due to consuming arsenic-contaminated food. PMID:23728998

Wang, Hong-Sheng; Sthiannopkao, Suthipong; Chen, Zhuo-Jia; Man, Yu-Bon; Du, Jun; Xing, Guang-Hua; Kim, Kyoung-Woong; Mohamed Yasin, Mohamed Salleh; Hashim, Jamal Hisham; Wong, Ming-Hung

2013-06-01

230

Using condition factor and blood variable biomarkers in fish to assess water quality.  

UK PubMed Central (United Kingdom)

The condition factor and blood variables, including erythrocyte lipid peroxidation (LPO) and the activity of antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx), in two ecologically distinct fish species (Astyanax fasciatus and Pimelodus maculatus) were evaluated at five sites in the Furnas Hydroelectric Power Station reservoir (Brazil) to assess water quality. Aldrin/dieldrin, endosulfan, heptachlor epoxide, and metolachlor were detected at different concentrations in four of the sites. Condition factor was not directly affected by such contaminants. A negative correlation between hematocrit and heptachlor was detected in P. maculatus. Positive correlations between red blood cells and heptachlor as well as an interactive effect of metolachlor and aldrin/dieldrin were detected in A. fasciatus. The erythrocytes of both species collected from the contaminated sites showed high levels of LPO, an increase in SOD and GPx activities and a decrease in CAT activity. Although the leukocyte number and the differential percentage of leukocytes varied among the sites, the hematological variables, the LPO levels, and the antioxidant enzyme activities could be used to assess water quality, regardless of the differences in the responses of the fish species.

Sadauskas-Henrique H; Sakuragui MM; Paulino MG; Fernandes MN

2011-10-01

231

Arsenic concentration in rice, fish, meat and vegetables in Cambodia: a preliminary risk assessment.  

UK PubMed Central (United Kingdom)

To assess arsenic contaminations and its possible adverse health effects, food samples were collected from Kandal, Kratie and Kampong Cham in Cambodia. The highest and the lowest concentrations were observed in fish (mean 2,832 ng g(-1), ww) collected from Kandal province and cattle stomach (1.86 ± 1.10 ng g(-1), ww) collected from Kratie, respectively. The daily intake of arsenic via food consumption was 604, 9.70 and 136 ?g day(-1) in Kandal, Kratie and Kampong Cham, respectively. The arsenic dietary intake in Kandal ranked No. 1 among all the 17 compared countries or regions. Fish consumption contributed the greatest proportion of total arsenic daily intake in Kandal (about 63.0 %) and Kampong Cham (about 69.8 %). It is revealed to be a much more important exposure pathway than drinking water for residents in Kampong Cham. The results of risk assessment suggested that the residents in Cambodia, particularly for people in Kandal province, suffer high public health risks due to consuming arsenic-contaminated food.

Wang HS; Sthiannopkao S; Chen ZJ; Man YB; Du J; Xing GH; Kim KW; Mohamed Yasin MS; Hashim JH; Wong MH

2013-06-01

232

Dose assessment of past accidental or chronic exposure using FISH chromosome painting  

International Nuclear Information System (INIS)

In order to evaluate the practicality of FISH (fluorescence in situ hybridisation) chromosome painting for retrospective biodosimetry, more information on the stability of translocations with time and the control level of translocations is needed. The temporal behaviour of translocation frequency in four accidentally exposed subjects showed that translocations remained relatively stable throughout the first post-accidental years. A decline in translocation yields was, however, observed in one subject exposed to both high dose and partial body irradiation that lead to severe aplasia. This finding implies that FISH biodosimetry may not be informative in cases where the dose has not been uniformly distributed. In our studies, significant age dependence and wide translocation range has been observed. In dose assessment of low dose exposure to a large number of people the age effect has been accounted for by comparing the results with a matched control group. Our data support the use of translocations for retrospective dosimetry for moderately high doses of the order of 1 Gy acute exposure with uniform whole-body exposures. In low dose chronic exposures, reliable assessment of past exposures can be achieved on group level. (author)

2000-01-01

233

Dredging of blue mussels ( Mytilus edulis L.) in a Danish sound: stock sizes and fishery-effects on mussel population dynamic  

DEFF Research Database (Denmark)

In April 1993, 1994 and 1995 the abundance of blue mussels, Mytilus edulis L., was estimated in Limfjorden, Denmark. The stocks were assessed by using a down-scaled model of a commercial mussel dredge which efficiency was analysed by comparing its samples with others collected by diver. The mean dredge efficiency was 17%. The fishing area in Limfjorden (700 km(2)) is divided into 22 fishery zones and mussel stock size was calculated for each zone. From April 1993 to April 1994 the total stock size declined from 771 000 to 616 000 t. In the same period, the exploitation rate in the fishery was 14% of the 1993 stock, and the size of mussel landings from each zone significantly correlated with their change in stock. In April 1995, the total mussel stock was reduced to 494 000 t. The mean exploitation rate in 1994-1995 was 15%. No correlation was observed between the size of mussel landings and the change in the mussel stock. In summer 1994, there was a long period of oxygen depletion in parts of Limfjorden. Thiscaused mortality of 33% of the mussels in the affected areas. In fishery zones without oxygen depletion a 46% increase in the mussel stocks was estimated. The massive loss of blue mussels caused by oxygen depletion exceeds the annual landings of mussels from the fishery. (C) 1999 Elsevier Science B.V. All rights reserved

Dolmer, Per; Kristensen, Per Sand

1999-01-01

234

A national risk assessment for intersex in fish arising from steroid estrogens.  

UK PubMed Central (United Kingdom)

The occurrence of intersex fish is widespread in the rivers of England and Wales. The extent of intersex in fish populations is believed to be strongly linked to their exposure to steroid estrogens. The present study presents, to our knowledge, the first national, catchment-based risk assessment for steroid estrogens in the world. A graphical information system-based model predicted the concentrations of estradiol (E2), estrone, and ethinylestradiol, which were combined and compared with known biological effect levels to predict the risk of endocrine disruption for 10,313 individual river reaches (21,452 km) receiving effluent from more than 2000 sewage treatment plants serving more than 29 million people. The large scale of this assessment underlines the usefulness of computer-based risk assessment methods. Overall, 61% [corrected] of the modeled reaches (all percentages are in terms of the total river length modeled) in England and Wales were predicted to be not at risk from endocrine disruption (mean concentrations, <1 ng/L E2 equivalents). A large range existed in the percentage of river reaches at risk in the various regions, from 5% in Wales to 67% in the Thames catchment. Important factors influencing this proportion are the population density, particularly their location, and the available dilution. A very small proportion of reaches (approximately 1-3%) were predicted to be at high risk (>10 ng/L E2 equivalents). Many of these high-risk reaches, however, were ditches, which were composed almost entirely of sewage effluent. The model could be applied equally well to any other chemical of concern emanating from the human population that would be impractical to assess by measurement.

Williams RJ; Keller VD; Johnson AC; Young AR; Holmes MG; Wells C; Gross-Sorokin M; Benstead R

2009-01-01

235

Fish Breeding in Nigeria  

Directory of Open Access Journals (Sweden)

Full Text Available Fish breeding is a very important activity ensuring availability of fingerlings for the stocking of ponds, pens, tanks and cages. The breeding habits of fishes in nature differ from specie to specie Different species of fish choose different places in the aquatic environment for breeding. Most species do not breed when in captivity due to a number of factors. In Nigeria, induced breeding of African mud catfish through injection of ova prim hormone or pituitary gland is the main practice. This article reviews the wild sources of fish seeds, some cultivable fishes. carp breeding, relationship between the endocrine system and gonad development, function of the Central Nervous System (CNS) in propagation, influence of ecological conditions on gonad development, artificial propagation of common carp, natural induced spawning, salmon culture and an innovation in the sea to educate fish breeders, fish genetics and fish culturist in other to facilitate their productivity.

J.A. Akankali; E.I. Seighabo; J.F.N. Abowei

2011-01-01

236

Laboratory and field assessment of the potential of larvivorous, air-breathing fishes as predators of culicine mosquitoes  

UK PubMed Central (United Kingdom)

The suitability of three indigenous, air-breathing fishes as predators of mosquito larvae were assessed under field and laboratory conditions using Culex quinquefasciatus as prey. In the laboratory, the fishes Anabas testudineus, Clarias batrachus and Heteropneustes fossilis consumed an average 14.4-1158.0 fourth-instar mosquito larvae/day. The prey consumption rate increased as a function of prey density but decreased with container size (range 2 to 16 l). For all three predatory fishes, the Manly's prey selectivity index for the mosquito larvae was not significantly lowered in presence of alternative preys that included areneids, chironomid larvae, small fishes and tadpoles. In the field the presence of these fish species in large experimental macrocosms significantly lowered the abundance of mosquito larvae. The results of predation pattern and the prey preference by the fishes, A. testudineus, C. batrachus and H. fossilis, support their use as biological resource in the mosquito larval habitats like rice fields and temporary pools to regulate the pest and vector mosquito populations. The habitat similarity with the mosquito immatures and the ability of these fishes to tolerate low level of oxygen in aquatic systems favor their augmentative release as a part of a biological control program.

Bhattacharjee Indranil; Aditya Gautam; Chandra Goutam

2009-05-01

237

Residual levels, tissue distribution and risk assessment of organochlorine pesticides (OCPs) in edible fishes from Taihu Lake, China.  

UK PubMed Central (United Kingdom)

Tissue distribution and bioaccumulation of organochlorine pesticides (OCPs) in edible fishes collected from Taihu Lake, Cyprinus carpio (C. carpio) and Ctenopharyngodon idellus (C. idellus), were studied. OCPs were detected in all samples with hexachlorocyclohexanes (HCHs), aldrins (including aldrin, dieldrin, endrin, endrin aldehyde, and endrin ketone), heptachlors (heptachlor and heptachlor epoxide) and dichlorodiphenyltrichloroethanes (DDTs) being the predominant compounds for both fish species. Gill and gonad were found to be the dominant tissues for OCP bioaccumulation followed by liver, while muscle showed the least affinity of OCPs for both fishes. Tissue distribution indicated the exchange of contaminants between water and gill, as well as the food intake from environment were the dominant pathways for OCP bioaccumulation in gill-breathing fish, and the following tissue distribution was affected by both the physiological properties of target tissues and physicochemical characteristics of pesticides. OCP residues in fish were species-specific (45.63-1575.26 ng/g dry weight (dw) for C. idellus; 8.40-60.23 ng/g dw for C. carpio) mainly due to the growth rate of individuals as well as the metabolic capacity difference among species. HCHs and DDTs observed in fishes from Taihu Lake were comparable and moderate with other reported places in China. Human exposure risk assessment performed with the estimated daily intake values demonstrated the consumption of target fish species in Taihu Lake at present was safe.

Zhao Z; Zhang L; Wu J; Fan C

2013-11-01

238

Residual levels, tissue distribution and risk assessment of organochlorine pesticides (OCPs) in edible fishes from Taihu Lake, China.  

Science.gov (United States)

Tissue distribution and bioaccumulation of organochlorine pesticides (OCPs) in edible fishes collected from Taihu Lake, Cyprinus carpio (C. carpio) and Ctenopharyngodon idellus (C. idellus), were studied. OCPs were detected in all samples with hexachlorocyclohexanes (HCHs), aldrins (including aldrin, dieldrin, endrin, endrin aldehyde, and endrin ketone), heptachlors (heptachlor and heptachlor epoxide) and dichlorodiphenyltrichloroethanes (DDTs) being the predominant compounds for both fish species. Gill and gonad were found to be the dominant tissues for OCP bioaccumulation followed by liver, while muscle showed the least affinity of OCPs for both fishes. Tissue distribution indicated the exchange of contaminants between water and gill, as well as the food intake from environment were the dominant pathways for OCP bioaccumulation in gill-breathing fish, and the following tissue distribution was affected by both the physiological properties of target tissues and physicochemical characteristics of pesticides. OCP residues in fish were species-specific (45.63-1575.26 ng/g dry weight (dw) for C. idellus; 8.40-60.23 ng/g dw for C. carpio) mainly due to the growth rate of individuals as well as the metabolic capacity difference among species. HCHs and DDTs observed in fishes from Taihu Lake were comparable and moderate with other reported places in China. Human exposure risk assessment performed with the estimated daily intake values demonstrated the consumption of target fish species in Taihu Lake at present was safe. PMID:23729160

Zhao, Zhonghua; Zhang, Lu; Wu, Jinglu; Fan, Chengxin

2013-06-01

239

Environmental and human health risk assessment of organic micro-pollutants occurring in a Spanish marine fish farm  

Energy Technology Data Exchange (ETDEWEB)

In this work the risk posed to seawater organisms, predators and humans is assessed, as a consequence of exposure to 12 organic micro-pollutants, namely metronidazole, trimethoprim, erythromycin, simazine, flumequine, carbaryl, atrazine, diuron, terbutryn, irgarol, diphenyl sulphone (DPS) and 2-thiocyanomethylthiobenzothiazole (TCMTB). The risk assessment study is based on a 1-year monitoring study at a Spanish marine fish farm, involving passive sampling techniques. The results showed that the risk threshold for irgarol concerning seawater organisms is exceeded. On the other hand, the risk to predators and especially humans through consumption of fish is very low, due to the low bioconcentration potential of the substances assessed. - Exposure and effects of twelve organic micro-pollutants are evaluated at a Spanish fish farm.

Munoz, Ivan, E-mail: ivanmuno@ual.e [Departamento de Hidrogeologia y Quimica Analitica, Universidad de Almeria, 04120 Almeria (Spain); Martinez Bueno, Maria J., E-mail: mjbueno@ual.e [Departamento de Hidrogeologia y Quimica Analitica, Universidad de Almeria, 04120 Almeria (Spain); Agueera, Ana, E-mail: aaguera@ual.e [Departamento de Hidrogeologia y Quimica Analitica, Universidad de Almeria, 04120 Almeria (Spain); Fernandez-Alba, Amadeo R., E-mail: amadeo@ual.e [Departamento de Hidrogeologia y Quimica Analitica, Universidad de Almeria, 04120 Almeria (Spain)

2010-05-15

240

Environmental and human health risk assessment of organic micro-pollutants occurring in a Spanish marine fish farm  

International Nuclear Information System (INIS)

In this work the risk posed to seawater organisms, predators and humans is assessed, as a consequence of exposure to 12 organic micro-pollutants, namely metronidazole, trimethoprim, erythromycin, simazine, flumequine, carbaryl, atrazine, diuron, terbutryn, irgarol, diphenyl sulphone (DPS) and 2-thiocyanomethylthiobenzothiazole (TCMTB). The risk assessment study is based on a 1-year monitoring study at a Spanish marine fish farm, involving passive sampling techniques. The results showed that the risk threshold for irgarol concerning seawater organisms is exceeded. On the other hand, the risk to predators and especially humans through consumption of fish is very low, due to the low bioconcentration potential of the substances assessed. - Exposure and effects of twelve organic micro-pollutants are evaluated at a Spanish fish farm.

2010-01-01

 
 
 
 
241

New Zealand boiler stock  

Energy Technology Data Exchange (ETDEWEB)

After brief descriptions of information sources on energy-using equipment and assessments of their usefulness, the records on steam boilers held by the Ministry of Transport are discussed in detail, and the data which were extracted from them are reviewed. The data are then analyzed at the national level, and regional patterns are explored. The analysis is intended primarily as an introduction to the main characteristics of the boiler stock; however, it also indicates how the information gathered might be used. Finally, some recommendations are made for the maintenance and up-dating of steam boiler records as a source of information on energy demand. (LEW)

Burton, B.; Jackson, L.

1982-07-01

242

Multibiomarker approach in Oreochromis mossambicus (Peters, 1892) fish to assess the impact of pollution in Mula River  

Directory of Open Access Journals (Sweden)

Full Text Available This article examines the advantages of the use of biomarkers as environmental indicators by applying it to Mula River, in Pune, which is in a critical environmental situation. We use a multi-biomarker approach in Oreochromis mossambicus fish as an integrated strategy to assess the impact of pollution. It comprehends a general biomarkers of fish immunity i.e. the respiratory burst activity, and specific biomarkers of contaminant exposure such as acetylcholinesterase (AChE) activity and oxidative stress. Our results revealed different effects in the fish from polluted river water than control fish. Activities of antioxidative enzymes, phagocytic activity and neurotransmitter activity was significantly influenced (P < 0.05) in dose dependent manner. This study indicates the usefulness of integrating a set of biomarkers to define the effects of anthropogenic inputs in aquatic bodies under complex polluted situations.

Dipti R. Gohil; Sapana B. Gadekar; Archana A. Sharbidre

2012-01-01

243

Risk assessment of N-nitrosodimethylamine formed endogenously after fish-with-vegetable meals.  

UK PubMed Central (United Kingdom)

The consumption of fish and nitrate-rich vegetables may lead to the formation of the genotoxic carcinogen N-nitrosodimethylamine (NDMA) in the stomach. To assess human cancer risk associated with this formation, a dynamic in vitro gastrointestinal model was used to simulate NDMA formation in the stomach after a fish + vegetable meal. The experimental results were combined with statistical modeling of Dutch food consumption data resulting in predicted exposures to endogenously formed NDMA in the population. The 95th percentile of the long-term exposure distribution was around 4 ng/kg-bw in young children and 0.4 ng/kg-bw in adults. By comparing this exposure with the Benchmark Dose Lower bound (BMDL) 10 for liver cancer in a chronic carcinogenicity study, a chronic margin of exposure (MOE) was calculated of 7000 and 73,000 for young children and adults. Furthermore, the long-term exposure distribution was combined with a dose-response analysis of the liver cancer incidence data to obtain a cancer risk distribution for the human population. The 95th percentile of that distribution was 6 x 10(-6) extra risk for 5-year-old children and 8 x 10(-7) for adults. The liver cancer data allowed for the analysis of the relationship between tumor incidence and time to tumor. For an extra risk of 10(-6), the decrease in time to tumor was conservatively estimated at 3.8 min in the rat, equivalent to 0.1 days in humans. We also combined acute exposure estimates with the BMDL10 from an acute carcinogenicity study for NDMA, resulting in an acute MOE of 110,000. We conclude that the combined consumption of fish and nitrate-rich vegetables appears to lead to marginal increases of additional cancer risk.

Zeilmaker MJ; Bakker MI; Schothorst R; Slob W

2010-07-01

244

Risk assessment of N-nitrosodimethylamine formed endogenously after fish-with-vegetable meals.  

Science.gov (United States)

The consumption of fish and nitrate-rich vegetables may lead to the formation of the genotoxic carcinogen N-nitrosodimethylamine (NDMA) in the stomach. To assess human cancer risk associated with this formation, a dynamic in vitro gastrointestinal model was used to simulate NDMA formation in the stomach after a fish + vegetable meal. The experimental results were combined with statistical modeling of Dutch food consumption data resulting in predicted exposures to endogenously formed NDMA in the population. The 95th percentile of the long-term exposure distribution was around 4 ng/kg-bw in young children and 0.4 ng/kg-bw in adults. By comparing this exposure with the Benchmark Dose Lower bound (BMDL) 10 for liver cancer in a chronic carcinogenicity study, a chronic margin of exposure (MOE) was calculated of 7000 and 73,000 for young children and adults. Furthermore, the long-term exposure distribution was combined with a dose-response analysis of the liver cancer incidence data to obtain a cancer risk distribution for the human population. The 95th percentile of that distribution was 6 x 10(-6) extra risk for 5-year-old children and 8 x 10(-7) for adults. The liver cancer data allowed for the analysis of the relationship between tumor incidence and time to tumor. For an extra risk of 10(-6), the decrease in time to tumor was conservatively estimated at 3.8 min in the rat, equivalent to 0.1 days in humans. We also combined acute exposure estimates with the BMDL10 from an acute carcinogenicity study for NDMA, resulting in an acute MOE of 110,000. We conclude that the combined consumption of fish and nitrate-rich vegetables appears to lead to marginal increases of additional cancer risk. PMID:20351056

Zeilmaker, Marco J; Bakker, Martine I; Schothorst, Ronald; Slob, Wout

2010-03-29

245

Assessment of Hydroponically Grown Macrophytes for Their Suitability as Fish Feed  

Directory of Open Access Journals (Sweden)

Full Text Available Water hyacinth, water lettuce and parrot's feather plants were examined for their ability to remove nutrients from aquaculture wastewater at two retention times. During the experiment, the aquatic plants grew rapidly in the hydroponics system and appeared healthy with green color. At hydraulic retention times (HRTs) of 6 and 12 days, the average water hyacinth, water lettuce and parrot's feather yields were 83, 51 and 51 g (dm) m-2 and 49, 29 and 22 g (dm) m-2, respectively. The aquatic plants were able to significantly reduce the pollution load of the aquaculture wastewater. The TS, COD, NH4+-N, NO2--N, NO3--N and PO43--P reductions ranged from 21.4 to 48.0%, from 71.1 to 89.5%, from 55.9 to 76.0%, from 49.6 to 90.6%, from 34.5 to 54.4% and from 64.5 to 76.8%, respectively. Generally, the reductions increased with longer retention times and were highest in compartments containing water hyacinth followed by compartments containing water lettuce and parrot's feather. The nutritive value of the three wastewater grown plants was assessed to determine the suitability of using the plants as a component in fish feed. The three wastewater grown plants did not contain sufficient amounts of protein and fat to meet the dietary requirements of fish and shellfish. They also contained high concentrations of K, Cu, Fe, Mn, Se and Zn, which can lead to reduced feed intake, weight gain and growth rates in fish and shellfish.

A. M. Snow; Abdel E. Ghaly

2008-01-01

246

Augmented Fish Health Monitoring for Washington Department of Wildlife, 1989 Annual Report.  

Energy Technology Data Exchange (ETDEWEB)

The augmented fish health monitoring project is funded by the Bonneville Power Administration (BPA) with the mandate to collect fish health data on anadromous fish stocks of the BPA Columbia River Basin in a standardized manner. The project began in 1986 and the data reported here was collected in the fourth year. This segment of the project was carried out by the Washington Department of Wildlife and summarizes fish health findings at anadromous game fish hatcheries in Washington State operated by the BPA. Information gathered to data has provided impetus to alter facility design and management practices for improved fish health through prevention. Treatment efficacy can be better assessed due to the monthly monitoring of fish stocks and insight is being gained into disease prevention and control. The ultimate goal, of course, is to improve fish health for better survival in the wild. Tagged returns at index hatcheries within this project area will provide some indication of the impact of improving fish health on providing greater adult returns as well as an improved product for the fishery. 3 refs., 2 figs., 16 tabs.

Kerwin, John L.; Roberts, Steve; Oman, Leni; Bolding, Bruce

1991-04-01

247

By-Catch Impacts in Fisheries: Utilizing the IUCN Red List Categories for Enhanced Product Level Assessment in Seafood LCAs.  

UK PubMed Central (United Kingdom)

Overexploitation of fish stocks causes concern not only to fisheries managers and conservation biologists, but also engages seafood consumers; more integrated product perspectives would be useful. This could be provided by life cycle assessment (LCA); however, further complements of present LCA methodology are needed to assess seafood production, one being by-catch impacts. We studied the scientific rationale behind using the IUCN Red List of Threatened Species™ for assessment of impacts relating to fish species' vulnerability. For this purpose, the current Red List status of marine fish in Sweden was compared to the advice given in fisheries as well as key life history traits known to indicate sensitivity to high fishing pressure. Further, we quantified the amount of threatened fish (vulnerable, endangered, or critically endangered) that was discarded in demersal trawl fisheries on the Swedish west coast. The results showed that not only did the national Red List of marine fish have a high consistency with advice given in fisheries and indices of vulnerability, the different fishing practices studied were also found to have vastly different amounts of threatened fish discarded per kilo landing. The suggested approach is therefore promising as a carrier of aggregated information on the extent to which seafood production interferes with conservation priorities, in particular for species lacking adequate stock assessment. To enable extensive product comparisons, it is important to increase coverage of fish species by the global IUCN Red List, and to reconsider the appropriate assessment unit (species or stocks) in order to avoid false alarms.

Hornborg S; Svensson M; Nilsson P; Ziegler F

2013-07-01

248

By-Catch Impacts in Fisheries: Utilizing the IUCN Red List Categories for Enhanced Product Level Assessment in Seafood LCAs.  

UK PubMed Central (United Kingdom)

Overexploitation of fish stocks causes concern not only to fisheries managers and conservation biologists, but also engages seafood consumers; more integrated product perspectives would be useful. This could be provided by life cycle assessment (LCA); however, further complements of present LCA methodology are needed to assess seafood production, one being by-catch impacts. We studied the scientific rationale behind using the IUCN Red List of Threatened Species™ for assessment of impacts relating to fish species' vulnerability. For this purpose, the current Red List status of marine fish in Sweden was compared to the advice given in fisheries as well as key life history traits known to indicate sensitivity to high fishing pressure. Further, we quantified the amount of threatened fish (vulnerable, endangered, or critically endangered) that was discarded in demersal trawl fisheries on the Swedish west coast. The results showed that not only did the national Red List of marine fish have a high consistency with advice given in fisheries and indices of vulnerability, the different fishing practices studied were also found to have vastly different amounts of threatened fish discarded per kilo landing. The suggested approach is therefore promising as a carrier of aggregated information on the extent to which seafood production interferes with conservation priorities, in particular for species lacking adequate stock assessment. To enable extensive product comparisons, it is important to increase coverage of fish species by the global IUCN Red List, and to reconsider the appropriate assessment unit (species or stocks) in order to avoid false alarms.

Hornborg S; Svensson M; Nilsson P; Ziegler F

2013-11-01

249

Interrenal dysfunction in fish from contaminated sites: In vivo and in vitro assessment  

Energy Technology Data Exchange (ETDEWEB)

Cortisol, synthesized in the interrenal cells of teleost head kidney, has a major role in the physiologic response to physical and chemical stressors. Plasma levels of cortisol increase in physiologically competent fish acutely exposed to stressors such as cadmium or mercury. The effects of chronic low level exposures are less well understood. The author has diagnosed an endocrine impairment characterized by a reduced capacity to elevate plasma cortisol levels in response to an acute standardized capture stress in yellow perch (Perca flavescens) and in northern pike (Esox lucius) sampled at sites contaminated by mixtures of pollutants (heavy metals, polycyclic aromatic hydrocarbons, and polychlorinated biphenyls), by heavy metals, or by bleached kraft mill effluent. The studies with fish, as well as with amphibians at contaminated sites, demonstrated that low level chronic exposures impair secretion of corticosteroids. The author has developed new tests for assessment of the functional integrity of teleost and amphibian interrenal tissue using an adrenocorticotropic hormone (ACTH) challenge, in vivo and in vitro. The reduced ability to respond to ACTH indicates that the normal neuroendocrine response to stressors may be disrupted and that the ability to cope with biotic and abiotic stressors in the environment may be significantly reduced in the impaired animals.

Hontela, A. [Univ. du Quebec, Montreal, Quebec (Canada)

1998-01-01

250

Flow cytometric assessment of DNA damage in the fish Catla catla (Ham.) exposed to gamma radiation  

International Nuclear Information System (INIS)

Environmental mutagens such as ionizing radiation and chemicals induce DNA damage in a wide variety of organisms. The International Commission on Radiological Protection (lCRP) has recently emphasized the need to protect non-human biota from the potential effects of ionizing radiation. Radiation exposures to non-humans can occur as a result of low-level radioactive discharges into the environment. Molecular genetic effects at low-level radiation exposures are largely unexplored and systematic studies using sensitive biomarkers are required to assess DNA damage in representative non-human species. The objective of the study was to detect DNA damage in the fish Catla catla exposed to gamma radiation using flow cytometry at different time intervals. Increases in the coefficient of variation (CV) of the G0/G1 peak, indicating abnormal DNA distributions were observed in fish exposed to gamma radiation than in controls. Significant increase in the CV was observed from day 12-90 and thereafter decreased. This increase in CV might be due to DNA damage in the cell populations at G0/G1 phase or deletions and duplications caused by improper repair of chromosomes in the cell-cycle machinery. Ionizing radiation induced cell-cycle perturbations and apoptosis were also observed after gamma radiation exposure. (author)

2012-01-01

251

Challenge of assessing climate change effects on fish and wildlife resources in the western United States  

Energy Technology Data Exchange (ETDEWEB)

This paper presents a preliminary assessment of the sensitivity of western US fish and wildlife habitats and representative species to various scenarios of change. Output from global climate change models and professional judgement of environmental scientists and natural resource managers was used to provide an initial assessment. The basic premise of model calculations was a doubling of atmospheric CO/sub 2/ concentrations and the resulting greenhouse effect. A conceptual monitoring strategy is presented that provides guidance on identification and selection of sensitive indicators that could be integrated into a program that assesses the functional response of ecosystems to climate change. Ideas are presented on how to develop a monitoring program that has the potential of showing detectable response within practical limits of time and effort. The last section of this report addresses management options and policy issues that require attention when assessing climate change effects on F and W resources. Items discussed include how to manage and set policy regarding: habitat protection; rare, threatened, and endangered species; level of management; monitoring; and future land acquisitions. These will be challenging issues that will require policy and management attention to protect F and W resources for future enjoyment. 35 refs., 6 tabs.

Breckenridge, R.P.; Otis, M.D.; Rope, R.C.; Cornish, J.G.; Trout, R.E.

1988-01-01

252

Public Review Draft: A Method for Assessing Carbon Stocks, Carbon Sequestration, and Greenhouse-Gas Fluxes in Ecosystems of the United States Under Present Conditions and Future Scenarios  

Science.gov (United States)

The Energy Independence and Security Act of 2007 (EISA), Section 712, authorizes the U.S. Department of the Interior to develop a methodology and conduct an assessment of the Nation's ecosystems focusing on carbon stocks, carbon sequestration, and emissions of three greenhouse gases (GHGs): carbon dioxide, methane, and nitrous oxide. The major requirements include (1) an assessment of all ecosystems (terrestrial systems, such as forests, croplands, wetlands, shrub and grasslands; and aquatic ecosystems, such as rivers, lakes, and estuaries), (2) an estimation of annual potential capacities of ecosystems to increase carbon sequestration and reduce net GHG emissions in the context of mitigation strategies (including management and restoration activities), and (3) an evaluation of the effects of controlling processes, such as climate change, land use and land cover, and wildlfires. The purpose of this draft methodology for public review is to propose a technical plan to conduct the assessment. Within the methodology, the concepts of ecosystems, carbon pools, and GHG fluxes used for the assessment follow conventional definitions in use by major national and international assessment or inventory efforts. In order to estimate current ecosystem carbon stocks and GHG fluxes and to understand the potential capacity and effects of mitigation strategies, the method will use two time periods for the assessment: 2001 through 2010, which establishes a current ecosystem GHG baseline and will be used to validate the models; and 2011 through 2050, which will be used to assess future potential conditions based on a set of projected scenarios. The scenario framework is constructed using storylines of the Intergovernmental Panel on Climate Change (IPCC) Special Report Emission Scenarios (SRES), along with initial reference land-use and land-cover (LULC) and land-management scenarios. An additional three LULC and land-management mitigation scenarios will be constructed for each storyline to enhance carbon sequestration and reduce GHG fluxes in ecosystems. Input from regional experts and stakeholders will be solicited to construct realistic and meaningful scenarios. The methods for mapping the current LULC and ecosystem disturbances will require the extensive use of both remote-sensing data and in-situ (for example, forest inventory data) to capture and characterize landscape-change events. For future potential LULC and ecosystem disturbances, key drivers such as socioeconomic, policy, and climate assumptions will be used in addition to biophysical data. The product of these analyses will be a series of maps for each future year for each scenario. These annual maps will form the basis for estimating carbon storage and GHG emissions. For terrestrial ecosystems, carbon storage, carbon-sequestration capacities, and GHG emissions under the current and projected future conditions will be assessed using the LULC and ecosystem-disturbance estimates in map format with a spatially explicit biogeochemical ensemble modeling system that incorporates properties of management activities (such as tillage or harvesting) and properties of individual ecosystems (such as elevation, vegetation characteristics, and soil attributes). For aquatic ecosystems, carbon burial in sediments and GHG fluxes are functions of the current and projected future stream flow and sediment transports, and therefore will be assessed using empirical modeling methods. Validation and uncertainty analysis methods described in the methodology will follow established guidelines to assess the quality of the assessment results. The U.S. Environmental Protection Agency's Level II ecoregions map (which delineates 24 ecoregions for the Nation) will be the practical instrument for developing and delivering assessment results. Consequently, the ecoregion will be the reporting unit of the assessment because the mitigation scenarios, assessment results, validation, and uncertainty analysis will be

Zhu, Zhiliang, ed.; Bergamaschi, Brian; Bernknopf, Richard; Clow, David; Dye, Dennis; Faulkner, Stephen; Forney, William; Gleason, Robert; Hawbaker, Todd; Liu, Jinxun; Liu, Shuguang; Prisley, Stephen; Reed, Bradley; Reeves, Matthew; Rollins, Matthew; Sleeter, Benjamin; Sohl, Terry; Stackpoole, Sarah; Stehman, Stephen; Striegl, Rob; Wein, Anne; Zhu, Zhiliang

2010-01-01

253

Variable stocking effect and endemic population genetic structure in Murray cod Maccullochella peelii.  

UK PubMed Central (United Kingdom)

Microsatellite markers were utilized to examine the genetic structure of Murray cod Maccullochella peelii throughout its distribution in the Murray--Darling Basin (MDB) of eastern Australia, and to assess the genetic effects of over three decades of stocking hatchery-reared fingerlings. Bayesian analysis using the programme Structure indicated that the species is largely genetically panmictic throughout much of its extensive range, most probably due to the high level of connectivity between catchments. Three catchments with terminal wetlands (the Lachlan, Macquarie and Gwydir), however, contained genetically distinct populations. No stocking effects were detected in the catchments that were genetically panmictic (either because of low genetic power or lack of effects), but the genetically differentiated Gwydir and Macquarie catchment populations were clearly affected by stocking. Conversely, there was no genetic evidence for survival and reproduction of stocked fish in the Lachlan catchment. Therefore, stocking of M. peelii throughout the MDB has resulted in a range of genetic effects ranging from minimal detectable effect, to substantial change in wild population genetic structure.

Rourke ML; McPartlan HC; Ingram BA; Taylor AC

2011-07-01

254

Stock enhancement programme for black sea bream, Acanthopagrus schlegelii (Bleeker), in Hiroshima Bay, Japan: a review  

UK PubMed Central (United Kingdom)

This paper reviews the stock enhancement programme for black sea bream (Acanthopagrus schlegelii) in Hiroshima Bay. This bay is one of the biggest production areas for black sea bream in Japan, accounting for about 10% of the total catch of the species in this country in 2004. After intensive fishing pressure caused a drastic decline in the catch of the species in this bay in the 1970s, a stock enhancement programme was conducted in its northern part since 1982 to restore the depleted population. The number of black sea bream juveniles released in 1996 surpassed 9 million, representing the third main species stocked in Japan. Almost 1.4 million of these juveniles were released into Hiroshima Bay. The fast acclimatization of hatchery-reared juveniles released into the bay may have contributed to the recovery of landings in the late 1980s and 1990s. However, this recovery was accompanied by a reduction in the market price of black sea bream. Further studies to assess the effectiveness of the stock enhancement programme as well as the carrying capacity of Hiroshima Bay to maintain the stock of black sea bream at a stable, healthy level are desirable. The necessity of evaluating the secondary effects derived from using a reduced number of breeders as well as finding new markets are suggested.

Gonzalez EB; Umino T; Nagasawa K

2008-09-01

255

Harvest Management and Recovery of Snake River Salmon Stocks : Recovery Issues for Threatened and Endangered Snake River Salmon : Technical Report 7 of 11.  

Energy Technology Data Exchange (ETDEWEB)

Management measures to regulate salmon fishing harvest have grown increasingly complex over the past decade in response to the needs for improved protection for some salmon runs and to alter harvest sharing between fisheries. The development of management plans that adequately address both needs is an immensely complicated task, one that involves a multitude of stocks, each with its own migration patterns and capacity to sustain exploitation. The fishing industry that relies on these fish populations is also highly diverse. The management task is made especially difficult because the stocks are often intermingled on the fishing grounds, creating highly mixed aggregates of stocks and species on which the fisheries operate. This situation is the one confronting harvest managers attempting to protect Snake River salmon. This report provides an overview of some of the factors that will need to be addressed in assessing the potential for using harvest management measures in the recovery of Snake River salmon stocks. The major sections of the report include the following: perspectives on harvest impacts; ocean distribution and in-river adult migration timing; description of management processes and associated fisheries of interest; and altemative harvest strategies.

Lestelle, Lawrence C.; Gilbertson, Larry G.

1993-06-01

256

From fish chemical characterisation to the benefit-risk assessment--part A.  

UK PubMed Central (United Kingdom)

Proximate composition, fatty acid profile, cholesterol, ?-tocoferol content and essential (K, Na, Cl, S, Mg, Ca, Zn, Cu, Fe, Mn, and Se) and contaminant element (Hg/MeHg, Cd, Pb, and As) levels in silver scabbardfish (Lepidopus caudatus), hake (Merluccius merluccius), and ray (Raja spp.) were investigated. Results showed that these species contain high protein, low cholesterol and energy levels, being its consumption recommended. Polyunsaturated fatty acids (PUFA) were the dominant group of the fatty acids, being 80% of the n-3 family. Attending to the dietary reference intakes (DRIs), these fish species are a good source of Se and the other minerals can give a relevant contribution to the DRIs in a balanced diet. More than one weekly meal of silver scabbardfish has to be avoided due to the organic mercury concentration. More accurate dietary recommendations require a probabilistic assessment, which will be the focus of this study's Part B.

Afonso C; Lourenço HM; Cardoso C; Bandarra NM; Carvalho ML; Castro M; Nunes ML

2013-04-01

257

Assessing Cumulative Thermal Stress in Fish During Chronic Exposure to High Temperature  

Energy Technology Data Exchange (ETDEWEB)

As environmental laws become increasingly protective, and with possible future changes in global climate, thermal effects on aquatic resources are likely to receive increasing attention. Lethal temperatures for a variety of species have been determined for situations where temperatures rise rapidly resulting in lethal effects. However, less is known about the effects of chronic exposure to high (but not immediately lethal) temperatures and even less about stress accumulation during periods of fluctuating temperatures. In this paper we present a modeling framework for assessing cumulative thermal stress in fish. The model assumes that stress accumulation occurs above a threshold temperature at a rate depending on the degree to which the threshold is exceeded. The model also includes stress recovery (or alleviation) when temperatures drop below the threshold temperature as in systems with large daily variation. In addition to non-specific physiological stress, the model also simulates thermal effects on growth.

Bevelhimer, M.S.; Bennett, W.R.

1999-11-14

258

Stock-based vs. fleet-based evaluation of the multi-annual management plan for the cod stocks in the Baltic Sea  

DEFF Research Database (Denmark)

This study evaluated the EU 2008 multi-annual plan for Baltic cod stock recovery. The plan combines harvest control rules that set TACs with reductions in direct effort (E) and fishing mortality (F). Performance and robustness of the plan are tested with a management strategy evaluation model (MSE). Stochastic simulations are carried out under different scenarios of recruitment and sources of uncertainties. Under the different magnitudes of errors investigated, the plan in its current design is likely to reach precautionary targets for the Eastern and the Western Baltic cod stocks by 2015. It is, however, more sensitive to implementation errors (e.g. catch misreporting) than to observation errors (e.g. data collection) when the (i) current settings of the ICES single-stock assessment model are maintained. (ii) intended fishing effort reduction is fully complied with, and (iii) biological parameters are assumed constant. For the Eastern Baltic stock, additional sources of uncertainties from fishery adaptation to the plan are tested using a fleet-based and spatially explicit version of the model which leads to higher reductions in F and no significant change in management robustness. The relative difference between both approaches is mainly due to differences in exploitation patterns in catching the same amount of fish. The effort control is demonstrated to be more efficient when supplemented with a TAC and avoids un-intended effects from fishery responses, e.g. spatial effort reallocation. Medium term economic evaluation of fishery performance shows an initial reduction in profit with effort and TAC reductions, but profit is always positive. (C) 2009 Elsevier B.V. All rights reserved.

Bastardie, Francois; Vinther, Morten

2010-01-01

259

Rapid assessment of the toxicity of oil sands process-affected waters using fish cell lines.  

UK PubMed Central (United Kingdom)

Rapid and reliable toxicity assessment of oil sands process-affected waters (OSPW) is needed to support oil sands reclamation projects. Conventional toxicity tests using whole animals are relatively slow, costly, and often subjective, while at the same time requiring the sacrifice of test organisms as is the case with lethal dosage/concentration assays. A nonlethal alternative, using fish cell lines, has been developed for its potential use in supporting oil sands reclamation planning and to help predict the viability of aquatic reclamation models such as end-pit lakes. This study employed six fish cell lines (WF-2, GFSk-S1, RTL-W1, RTgill-W1, FHML, FHMT) in 24 h viability assays for rapid fluorometric assessment of cellular integrity and functionality. Forty-nine test water samples collected from the surface of oil sands developments in the Athabasca Oil Sands deposit, north of Fort McMurray, Alberta, Canada, were evaluated in blind. Small subsample volumes (8 ml) were mixed with 2 ml of 5× concentrated exposure media and used for direct cell exposures. All cell line responses in terms of viability as measured by Alamar blue assay, correlated well with the naphthenic acids (NA) content in the samples (R (2) between 0.4519 and 0.6171; p<0.0001) when data comparisons were performed after the bioassays. NA or total acid-extractable organics group has been shown to be responsible for most of the acute toxicity of OSPW and our results further corroborate this. The multifish cell line bioassay provides a strong degree of reproducibility among tested cell lines and good relative sensitivity of the cell line bioassay as compared to available in vivo data that could lead to cost effective, high-throughput screening assays.

Sansom B; Vo NT; Kavanagh R; Hanner R; Mackinnon M; Dixon DG; Lee LE

2013-01-01

260

Rapid assessment of the toxicity of oil sands process-affected waters using fish cell lines.  

Science.gov (United States)

Rapid and reliable toxicity assessment of oil sands process-affected waters (OSPW) is needed to support oil sands reclamation projects. Conventional toxicity tests using whole animals are relatively slow, costly, and often subjective, while at the same time requiring the sacrifice of test organisms as is the case with lethal dosage/concentration assays. A nonlethal alternative, using fish cell lines, has been developed for its potential use in supporting oil sands reclamation planning and to help predict the viability of aquatic reclamation models such as end-pit lakes. This study employed six fish cell lines (WF-2, GFSk-S1, RTL-W1, RTgill-W1, FHML, FHMT) in 24 h viability assays for rapid fluorometric assessment of cellular integrity and functionality. Forty-nine test water samples collected from the surface of oil sands developments in the Athabasca Oil Sands deposit, north of Fort McMurray, Alberta, Canada, were evaluated in blind. Small subsample volumes (8 ml) were mixed with 2 ml of 5× concentrated exposure media and used for direct cell exposures. All cell line responses in terms of viability as measured by Alamar blue assay, correlated well with the naphthenic acids (NA) content in the samples (R (2) between 0.4519 and 0.6171; p<0.0001) when data comparisons were performed after the bioassays. NA or total acid-extractable organics group has been shown to be responsible for most of the acute toxicity of OSPW and our results further corroborate this. The multifish cell line bioassay provides a strong degree of reproducibility among tested cell lines and good relative sensitivity of the cell line bioassay as compared to available in vivo data that could lead to cost effective, high-throughput screening assays. PMID:23263937

Sansom, Bryan; Vo, Nguyen T K; Kavanagh, Richard; Hanner, Robert; Mackinnon, Michael; Dixon, D George; Lee, Lucy E J

2012-12-14

 
 
 
 
261

Factors in exposure assessment: Ethnic and socio-economic differences in fishing and consumption of fish caught along the Savannah River  

Energy Technology Data Exchange (ETDEWEB)

South Carolina has issued fish consumption advisories for the Savannah River based on mercury and radionuclide levels. The authors examine differences in fishing rates and fish consumption of 258 people interviewed while fishing along the Savannah River, as a function of age, education, ethnicity, employment history, and income, and test the assumption that the average consumption of fish is less than the recreational value of 19 kg/year assumed by risk assessors. Ethnicity and education contributed significantly to explaining variations in number of fish meals per month, serving size, and total quantity of fish consumed per year. Blacks fished more often, ate more fish meals of slightly larger serving sizes, and consumed more fish per year than did Whites. Although education and income were correlated, education contributed most significantly to behavior; people who did not graduate from high school ate fish more often, ate more fish per year, and ate more whole fish than people who graduated from high school. Computing consumption of fish for each person individually indicates that (1) people who eat fish more often also eat larger portions, (2) a substantial number of people consume more than the amount of fish used to compute risk to recreational fishermen, (3) some people consume more than the subsistence level default assumption (50 kg/year) and (4) Blacks consume more fish per year than Whites, putting them at greater risk from contaminants in fish. Overall, ethnicity, age, and education contributed to variations in fishing behavior and consumption.

Burger, J. [Rutgers-the State Univ., Piscataway, NJ (United States). Nelson Biological Lab.]|[Environmental and Occupational health Sciences Inst., Piscataway, NJ (United States); Stephens, W.L.; Boring, C.S. [Environmental and Occupational health Sciences Inst., Piscataway, NJ (United States)]|[Savannah River Ecology Lab., Aiken, SC (United States); Kuklinski, M. [Environmental and Occupational health Sciences Inst., Piscataway, NJ (United States); Gibbons, J.W. [Savannah River Ecology Lab., Aiken, SC (United States); Gochfeld, M. [Environmental and Occupational Health Sciences Inst., Piscataway, NJ (United States)]|[Univ. of Medicine and Dentistry of New Jersey, Newark, NJ (United States). Robert Wood Johnson Medical School

1999-06-01

262

The IUCN Red List of Threatened Species: an assessment of coral reef fishes in the US Pacific Islands  

Science.gov (United States)

Widespread declines among many coral reef fisheries have led scientists and managers to become increasingly concerned over the extinction risk facing some species. To aid in assessing the extinction risks facing coral reef fishes, large-scale censuses of the abundance and distribution of individual species are critically important. We use fisheries-independent data collected as part of the NOAA Pacific Reef Assessment and Monitoring Program from 2000 to 2009 to describe the range and density across the US Pacific of coral reef fishes included on The International Union for the Conservation of Nature's (IUCN) 2011 Red List of Threatened Species. Forty-five species, including sharks, rays, groupers, humphead wrasse ( Cheilinus undulatus), and bumphead parrotfish ( Bolbometopon muricatum), included on the IUCN List, were recorded in the US Pacific Islands. Most species were generally rare in the US Pacific with the exception of a few species, principally small groupers and reef sharks. The greatest diversity and densities of IUCN-listed fishes were recorded at remote and uninhabited islands of the Pacific Remote Island Areas; in general, lower densities were observed at reefs of inhabited islands. Our findings complement IUCN assessment efforts, emphasize the efficacy of large-scale assessment and monitoring efforts in providing quantitative data on reef fish assemblages, and highlight the importance of protecting populations at remote and uninhabited islands where some species included on the IUCN Red List of Threatened Species can be observed in abundance.

Zgliczynski, B. J.; Williams, I. D.; Schroeder, R. E.; Nadon, M. O.; Richards, B. L.; Sandin, S. A.

2013-09-01

263

Possibility of manufacturing lube base stocks from Bombay High crude  

Energy Technology Data Exchange (ETDEWEB)

Lube base stocks production potential of BH crude oil has been assessed both in terms of quality and quantity. Data obtained are discussed with some important imported crudes known to yield acceptable quality of lube base stocks in economical yields. Some views on possible utilization of BH lube base stocks are also presented.

Singh, H.; Gupta, P.C.; Anwar, M.; Chaudhary, G.S.; Kishore, K.; Kaushik, R.S.; Kumar, M.M.; Lal, M.

1985-12-01

264

Genetic analyses of Asian seabass stocks using novel polymorphic microsatellites  

UK PubMed Central (United Kingdom)

To study genetic diversity of two cultured and one wild stock of Asian seabass (Lates calcarifer) in South-East Asia and their relationships, thirty-six polymorphic microsatellites were isolated from partial genomic libraries. The average allele number of the 36 microsatellites present among 32 individuals, was 7.4/locus, ranging from 2 to 17. One multiplex PCR set of nine polymorphic microsatellites was used to genotype 294 individuals from three stocks. High levels of allelic and genetic diversity were observed in all three stocks (average allele number = 8.2/locus and He = 0.75 in the wild stock; allele number = 9.6 and He = 0.76 in Singapore stock I; and allele number = 8.0 and He = 0.72 in Singapore stock II). FIS values within each stock were very low. Significant genetic differentiation (FST = 0.03, P < 0.05) and private alleles were detected among the three stocks. Thus, it may be possible to form a new superior broodstock with high genetic diversity by combining fish from different stocks. The developed polymorphic microsatellites, and especially the multiplex PCR set, are useful in monitoring genetic diversity of cultured stocks and for studying the genetic structure of wild stocks of Asian seabass.

Zhu ZY; Lin G; Lo LC; Xu YX; Feng F; Chou R; Yue GH

2006-06-01

265

Assessment of Heavy Metals in the Fish Collected from the River Ravi, Pakistan  

Directory of Open Access Journals (Sweden)

Full Text Available The toxicity of heavy metals viz. aluminium (Al), arsenic (As), barium (Ba), chromium (Cr), nickel (Ni) and zinc (Zn) in fish at three main public fishing sites of the river Ravi viz. Shahdara bridge, Baloki headworks and Sidhnai barrage has been studied from June, 2009 to May, 2010. The concentrations of heavy metals in the body organs (gills, liver, kidney, intestine, reproductive organs, skin, muscle, fins, scales, bones, fats) of three fish species viz. Catla catla, Labeo rohita and Cirrhina mrigala were determined. The present results reveal that the toxicity of metals fluctuated significantly in fish at all the three sampling stations with season. The fish samples collected from all the three sampling stations had significantly higher aluminium and zinc. However, the fish at Sidhnai barrage showed significantly lower metallic toxicity, followed by that at Baloki headworks and Shahdara bridge. Significantly higher metals were observed in fish liver, followed by that of kidney, gills, intestine, reproductive organs, skin, scales, fins, bones, muscle and fats. The accumulation of metals in carnivorous fish body organs showed significantly direct dependence on the metallic toxicity of herbivorous cyprinids. Fish liver and kidney showed significantly higher abilities for the accumulation of all metals while accumulations were lowest in fish muscle and fats. The health status of river Ravi at three main public fishing sites viz. Shahdara bridge, Baloki headworks and Sidhnai barrage, with respect to eco-toxicity of Al, As, Ba, Cr, Ni and Zn was above the recommended permissible standards.

Ghazala Jabeen*, Muhammad Javed and Hamda Azmat

2012-01-01

266

Exposure and effects assessment of persistent organohalogen contaminants in arctic wildlife and fish.  

UK PubMed Central (United Kingdom)

Persistent organic pollutants (POPs) encompass an array of anthropogenic organic and elemental substances and their degradation and metabolic byproducts that have been found in the tissues of exposed animals, especially POPs categorized as organohalogen contaminants (OHCs). OHCs have been of concern in the circumpolar arctic for decades. For example, as a consequence of bioaccumulation and in some cases biomagnification of legacy (e.g., chlorinated PCBs, DDTs and CHLs) and emerging (e.g., brominated flame retardants (BFRs) and in particular polybrominated diphenyl ethers (PBDEs) and perfluorinated compounds (PFCs) including perfluorooctane sulfonate (PFOS) and perfluorooctanic acid (PFOA) found in Arctic biota and humans. Of high concern are the potential biological effects of these contaminants in exposed Arctic wildlife and fish. As concluded in the last review in 2004 for the Arctic Monitoring and Assessment Program (AMAP) on the effects of POPs in Arctic wildlife, prior to 1997, biological effects data were minimal and insufficient at any level of biological organization. The present review summarizes recent studies on biological effects in relation to OHC exposure, and attempts to assess known tissue/body compartment concentration data in the context of possible threshold levels of effects to evaluate the risks. This review concentrates mainly on post-2002, new OHC effects data in Arctic wildlife and fish, and is largely based on recently available effects data for populations of several top trophic level species, including seabirds (e.g., glaucous gull (Larus hyperboreus)), polar bears (Ursus maritimus), polar (Arctic) fox (Vulpes lagopus), and Arctic charr (Salvelinus alpinus), as well as semi-captive studies on sled dogs (Canis familiaris). Regardless, there remains a dearth of data on true contaminant exposure, cause-effect relationships with respect to these contaminant exposures in Arctic wildlife and fish. Indications of exposure effects are largely based on correlations between biomarker endpoints (e.g., biochemical processes related to the immune and endocrine system, pathological changes in tissues and reproduction and development) and tissue residue levels of OHCs (e.g., PCBs, DDTs, CHLs, PBDEs and in a few cases perfluorinated carboxylic acids (PFCAs) and perfluorinated sulfonates (PFSAs)). Some exceptions include semi-field studies on comparative contaminant effects of control and exposed cohorts of captive Greenland sled dogs, and performance studies mimicking environmentally relevant PCB concentrations in Arctic charr. Recent tissue concentrations in several arctic marine mammal species and populations exceed a general threshold level of concern of 1 part-per-million (ppm), but a clear evidence of a POP/OHC-related stress in these populations remains to be confirmed. There remains minimal evidence that OHCs are having widespread effects on the health of Arctic organisms, with the possible exception of East Greenland and Svalbard polar bears and Svalbard glaucous gulls. However, the true (if any real) effects of POPs in Arctic wildlife have to be put into the context of other environmental, ecological and physiological stressors (both anthropogenic and natural) that render an overall complex picture. For instance, seasonal changes in food intake and corresponding cycles of fattening and emaciation seen in Arctic animals can modify contaminant tissue distribution and toxicokinetics (contaminant deposition, metabolism and depuration). Also, other factors, including impact of climate change (seasonal ice and temperature changes, and connection to food web changes, nutrition, etc. in exposed biota), disease, species invasion and the connection to disease resistance will impact toxicant exposure. Overall, further research and better understanding of POP/OHC impact on animal performance in Arctic biota are recommended. Regardless, it could be argued that Arctic wildlife and fish at the highest potential risk of POP/OHC exposure and mediated effects are East Greenland, Svalbard and (West and South) Hudson Bay

Letcher RJ; Bustnes JO; Dietz R; Jenssen BM; Jørgensen EH; Sonne C; Verreault J; Vijayan MM; Gabrielsen GW

2010-07-01

267

Estuarine fish health assessment: Evidence of wastewater impacts based on nitrogen isotopes and histopathology  

International Nuclear Information System (INIS)

Sewage effluent is a powerful agent of ecological change in estuaries. While the effects of sewage pollution on water quality are usually well documented, biological responses of exposed organisms are not. We quantified health impacts in the form of pathological tissue changes across multiple organs in estuarine fish exposed to elevated levels of treated wastewater. Structural pathologies were compared in wild populations of four fish species from two subtropical estuaries on the east coast of Australia that differ substantially in the amount of direct wastewater loadings. Uptake of sewage-derived nitrogen by fish was traced with stable nitrogen isotopes. Pathologies were common in the liver, spleen, gill, kidney and muscle tissues, and included granulomas, melanomacrophage aggregates, and multiple deformities of the gill epithelia. Tissue deformities were more frequent in fish exposed directly to wastewater discharges. Mullet (Valamugil georgii) were most affected, with only a single specimen free of pathologies in the sewage-impacted estuary. Similarly, in those fish that had structural abnormalities, more deformities were generally found in individuals from sites receiving sewage. These spatial contrasts in impaired fish health correspond to significantly enriched ?15N values in fish muscle as a consequence of fish assimilating sewage-N. Overall, the pattern of lower health and enriched ?15N values in fish from sewage-impacted areas suggests that organism health is lowered by sewage inputs to estuaries. Measurements of organism health are required to understand the effects of sewage on estuarine ecosystems, and histopathology of fishes is a powerful tool to achieve this.

2007-01-01

268

Consequences of bias in age estimation on assessment of the northern stock of European hake (Merluccius merluccius) and on management advice  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The results of a pilot tagging study on hake (Merluccius merluccius), conducted in the northern part of the Bay of Biscay in 2002, indicate that growth rates for this stock may be currently underestimated because of biased estimates of age. The impact that such a bias may have on the stock dynamics ...

Bertignac Michel; De Pontual Helene

269

Dispersal, growth, and diet of stocked and wild northern pike fry in a shallow natural lake, with implications for the management of stocking programs  

DEFF Research Database (Denmark)

Increasing evidence suggests that stocking northern pike Esox lucius has had limited success, especially when age-0 fish are stocked into water bodies where the recruitment of northern pike already occurs. To better understand the ecology of wild and stocked fry, we investigated the dispersal, growth, and food composition of advanced pike fry (similar to 30 mm) stocked at a high density at a common release site in a shallow natural lake that contained wild young-of- the-year (age-0) pike. The stocked pike fry colonized the entire lake shoreline within just a few days. Dispersal was inversely related to size at stocking, suggesting that smaller fish were displaced by competitively superior larger individuals. While the stocked pike were initially larger than the wild age-0 pike, suboptimal growth was evident among the stocked pike and they were smaller than the wild ones at the end of the growing season. Stomach analyses revealed that the stocked pike ingested less diverse prey items and had higher fractions of empty stomachs throughout the study period. Overall, the fraction of stocked pike in samples rapidly declined over the season, which may have been caused by differential survival or immigration into or emigration out of the study system. Our study adds to the existing literature suggesting that the stocking of age-0 northern pike into waters with naturally reproducing pike populations will result in limited success. We propose two potentially complementary explanations for the apparent low fitness of stocked individuals in competition with wild conspecifics: (1) genetic-based local maladaptation among the stocked fish and (2) carryover effects from the hatchery. The latter may be less likely because the fry stocked were the offspring of wild fish and only spent a few weeks in the hatchery.

Skov, Christian Houlberg; Koed, Anders

2011-01-01

270

Dispersal, growth and diet of stocked and wild northern pike fry in a shallow natural lake, with implications for management of stocking programs  

DEFF Research Database (Denmark)

Increasing evidence suggests that stocking northern pike Esox lucius has had limited success, especially when age-0 fish are stocked into water bodies where the recruitment of northern pike already occurs. To better understand the ecology of wild and stocked fry, we investigated the dispersal, growth, and food composition of advanced pike fry (?30 mm) stocked at a high density at a common release site in a shallow natural lake that contained wild youngof- the-year (age-0) pike. The stocked pike fry colonized the entire lake shoreline within just a few days. Dispersal was inversely related to size at stocking, suggesting that smaller fish were displaced by competitively superior larger individuals. While the stocked pike were initially larger than the wild age-0 pike, suboptimal growth was evident among the stocked pike and they were smaller than the wild ones at the end of the growing season. Stomach analyses revealed that the stocked pike ingested less diverse prey items and had higher fractions of empty stomachs throughout the study period. Overall, the fraction of stocked pike in samples rapidly declined over the season, which may have been caused by differential survival or immigration into or emigration out of the study system. Our study adds to the existing literature suggesting that the stocking of age-0 northern pike into waters with naturally reproducing pike populations will result in limited success. We propose two potentially complementary explanations for the apparent low fitness of stocked individuals in competition with wild conspecifics: (1) genetic-based local maladaptation among the stocked fish and (2) carryover effects from the hatchery. The latter may be less likely because the fry stocked were the offspring of wild fish and only spent a few weeks in the hatchery

Skov, Christian; Koed, Anders

2011-01-01

271

Augmented Fish Health Monitoring for Washington Department of Wildlife, 1988 Annual Report.  

Energy Technology Data Exchange (ETDEWEB)

The augmented fish health monitoring project is funded by the Bonneville Power Administration with the mandate to collect fish health data on anadromous fish stocks of the Columbia River Basin in a standardized manner. The project began in 1986 and the data reported here was collected in the third year. This segment of the project was carried out by the Washington Department of Wildlife and summarizes fish health findings at anadromous game hatcheries in Washington State operated by the BPA. Information gathered to date has provided impetus to alter facility design and management practices for improved fish health through prevention. Treatment efficacy can be better assessed due to the monthly monitoring of fish stocks and insight is being gained into disease prevention and control. The ultimate goal, of course, is to improve fish health for better survival in the wild. Tagged returns at index hatcheries within this project area will indicate the impact of improving fish health on providing greater adult returns as well as an improved product for the fishery. 2 refs., 3 figs., 15 tabs.

Gearheard, Jim

1988-10-01

272

Fugitive Salmon: Assessing the Risks of Escaped Fish from Net-Pen Aquaculture  

Science.gov (United States)

This peer-reviewed resource from BioScience journal is the risks associated with aquaculture.The farming of salmon and other marine finfish in open net pens continues to increase along the world's coastlines as the aquaculture industry expands to meet human demand. Farm fish are known to escape from pens in all salmon aquaculture areas. Their escape into the wild can result in interbreeding and competition with wild salmon and can facilitate the spread of pathogens, thereby placing more pressure on already dwindling wild populations. Here we assess the ecological, genetic, and socioeconomic impacts of farm salmon escapes, using a risk-assessment framework. We show that risks of damage to wild salmon populations, ecosystems, and society are large when salmon are farmed in their native range, when large numbers of salmon are farmed relative to the size of wild populations, and when exotic pathogens are introduced. We then evaluate the policy and management options for reducing risks and discuss the implications for farming other types of marine finfish.

ROSAMOND NAYLOR, KJETIL HINDAR, IAN A. FLEMING, REBECCA GOLDBURG, SUSAN WILLIAMS, JOHN VOLPE, FRED WHORISKEY, JOSH EAGLE, DENNIS KELSO, and MARC MANGEL (;)

2005-05-01

273

Stocking impact and temporal stability of genetic composition in a brackish northern pike population (Esox lucius L.), assessed using microsatellite DNA analysis of historical and contemporary samples.  

Science.gov (United States)

During the last decade, brackish northern pike populations in Denmark have been subject to stocking programmes, using nonindigenous pike from freshwater lakes, in order to compensate for drastic population declines. The present study was designed to investigate the genetic impact of stocking freshwater pike into a brackish pike population in Stege Nor, Denmark. We analysed polymorphism at eight microsatellite loci in samples representing the indigenous Stege Nor population prior to stocking (ie from 1956 to 1957), along with a sample of the contemporary Stege Nor population and samples from the three populations used for stocking. Despite large numbers of stocked fry, the results from both individual and population level admixture analyses demonstrated extremely poor performance and 250), but there were indications of bottlenecks in all samples and populations. We ascribe this finding to historical rather than recent bottlenecks, possibly dating back to founder events associated with postglacial recolonisation. PMID:15999144

Larsen, P F; Hansen, M M; Nielsen, E E; Jensen, L F; Loeschcke, V

2005-08-01

274

Stocking impact and temporal stability of genetic composition in a brackish northern pike population ( Esox lucius L.), assessed using microsatellite DNA analysis of historical and contemporary samples  

DEFF Research Database (Denmark)

During the last decade, brackish northern pike populations in Denmark have been subject to stocking programmes, using nonindigenous pike from freshwater lakes, in order to compensate for drastic population declines. The present study was designed to investigate the genetic impact of stocking freshwater pike into a brackish pike population in Stege Nor, Denmark. We analysed polymorphism at eight microsatellite loci in samples representing the indigenous Stege Nor population prior to stocking (ie from 1956 to 1957), along with a sample of the contemporary Stege Nor population and samples from the three populations used for stocking. Despite large numbers of stocked fry, the results from both individual and population level admixture analyses demonstrated extremely poor performance and 250), but there were indications of bottlenecks in all samples and populations. We ascribe this finding to historical rather than recent bottlenecks, possibly dating back to founder events associated with postglacial recolonisation.

Larsen, Peter Foged; Hansen, Michael MØller

2005-01-01

275

Hexavalent chromium in fish from the Sepetiba Bay in Rio de Janeiro, Brazil: a risk assessment to human health  

Directory of Open Access Journals (Sweden)

Full Text Available Introduction: Certain metals, among them hexavalent chromium influence the stability of ecosystems and cause adverse effects on human health. Thus, this study aimed to estimate a risk model of human health associated with fish consumption from the Sepetiba Bay. Methodology: This risk assessment methodology was developed by the United States Environmental Protection Agency (USEPA). The models were implemented using the USEPA toxicological databases and samples from the Sepetiba Bay, Rio de Janeiro. Results: The intoxication and carcinogenic risk estimated for fish consumption of M. furnieri and C. acoupa species were considered small. Conclusion: Based on the analysis, we conclude that the toxicological risk or carcinogenic injury to health due to fish consumption with high levels of cromo6+ coming from Sepetiba Bay is low. Still, it emphasizes the validity of utilizing monitoring methods in coastal environments, for health and environmental control.

Adalberto Luiz Miranda Filho; Anne Karin Madureira da Mota; Carla da Costa Cruz; Carlos Alexandre Rey Matias; Aldo Pacheco Ferreira

2011-01-01

276

Screening level dose rate assessment of fishes exposed to artificial radionuclides of the Beloyarskoe storage pond  

International Nuclear Information System (INIS)

Aquatic biota in the Beloyarskoe storage pond of the nuclear power station are exposed to radioactivity released from the fast-breeder reactor. A simple conservative screening level model was used to estimate absorbed (whole body) dose rates for aquatic organisms. Four species of fishes were studied, (non-bottom-feeding fish, and bottom-feeding fish). The analysis was based on radionuclide concentrations reported in papers published by Russian Academy of Sciences. (authors)

2000-01-01

277

Arsenic contamination in the freshwater fish ponds of Pearl River Delta: bioaccumulation and health risk assessment.  

UK PubMed Central (United Kingdom)

This study investigated the extent of arsenic (As) contamination in five common species of freshwater fish (northern snakehead [Channa argus], mandrarin fish [Siniperca chuatsi], largemouth bass [Lepomis macrochirous], bighead carp [Aristichthys nobilis] and grass carp [Ctenopharyngodon idellus]) and their associated fish pond sediments collected from 18 freshwater fish ponds around the Pearl River Delta (PRD). The total As concentrations detected in fish muscle and sediment in freshwater ponds around the PRD were 0.05-3.01 mg kg(-1) wet weight (w. wt) and 8.41-22.76 mg kg(-1) dry weight (d. wt), respectively. In addition, the As content was positively correlated (p < 0.05) to total organic carbon (TOC) contents in sediments. Biota sediment accumulation factor (BSAF) showed that omnivorous fish and zooplankton accumulated higher concentrations of heavy metals from the sediment than carnivorous fish. In addition, feeding habits of fish also influence As accumulation in different fish species. In this study, two typical food chains of the aquaculture ponds were selected for investigation: (1) omnivorous food chain (zooplankton, grass carp and bighead carp) and (2) predatory food chain (zooplankton, mud carp and mandarin fish). Significant linear relationships were obtained between log As and ? (15)N. The slope of the regression (-0.066 and -0.078) of the log transformed As concentrations and ? (15)N values, as biomagnifications power, indicated there was no magnification or diminution of As from lower trophic levels (zooplankton) to fish in the aquaculture ponds. Consumption of largemouth bass, northern snakehead and bighead carp might impose health risks of Hong Kong residents consuming these fish to the local population, due to the fact that its cancer risk (CR) value exceeded the upper limit of the acceptable risk levels (10(-4)) stipulated by the USEPA.

Cheng Z; Chen KC; Li KB; Nie XP; Wu SC; Wong CK; Wong MH

2013-07-01

278

Assessing the roles of environmental factors in coastal fish production in the northern Baltic Sea: a Bayesian network application.  

Science.gov (United States)

Environmental conditions play a crucial role in the distribution and abundance of fish species in any area. Much research has been attributed to the requirements and tolerance limits of commercially exploited fish species. It is rare, however, that studies have been able to address the relative importance of potentially restrictive environmental factors; extensive enough to allow for estimation of the effect of several environmental factors through the fishes' life span. The coastline of Finland in the northern Baltic Sea offers a unique natural experimental setting that can be used to assess the relative importance of various environmental factors for the species occupying it. The area includes major variations in several crucial environmental factors: salinity, temperature regime, represented by winter ice duration, coastline characteristics, and eutrophic status. Furthermore, Finland has collected extensive and spatially representative data of water quality and environmental factors, as well as a long and extraordinarily spatially detailed data set of commercial catches of several fish species. In this article, we make an attempt to correlate the environmental data to the commercial catches of fish species, assuming that the commercial catches reflect, to some reasonable degree, the productivity of that species in that area (compared to other areas and combinations of environmental factors, not to other species). We use a Bayesian network approach to examine the sensitivity of the species to the environmental factors. PMID:21309077

Uusitalo, Laura; Kuikka, Sakari; Kauppila, Pirkko; Söderkultalahti, Pirkko; Bäck, Saara

2011-03-23

279

Assessing the roles of environmental factors in coastal fish production in the northern Baltic Sea: a Bayesian network application.  

UK PubMed Central (United Kingdom)

Environmental conditions play a crucial role in the distribution and abundance of fish species in any area. Much research has been attributed to the requirements and tolerance limits of commercially exploited fish species. It is rare, however, that studies have been able to address the relative importance of potentially restrictive environmental factors; extensive enough to allow for estimation of the effect of several environmental factors through the fishes' life span. The coastline of Finland in the northern Baltic Sea offers a unique natural experimental setting that can be used to assess the relative importance of various environmental factors for the species occupying it. The area includes major variations in several crucial environmental factors: salinity, temperature regime, represented by winter ice duration, coastline characteristics, and eutrophic status. Furthermore, Finland has collected extensive and spatially representative data of water quality and environmental factors, as well as a long and extraordinarily spatially detailed data set of commercial catches of several fish species. In this article, we make an attempt to correlate the environmental data to the commercial catches of fish species, assuming that the commercial catches reflect, to some reasonable degree, the productivity of that species in that area (compared to other areas and combinations of environmental factors, not to other species). We use a Bayesian network approach to examine the sensitivity of the species to the environmental factors.

Uusitalo L; Kuikka S; Kauppila P; Söderkultalahti P; Bäck S

2012-07-01

280

Concentration and exposure assessment of mercury in commercial fish and other seafood marketed in Oman.  

UK PubMed Central (United Kingdom)

The results of this study present analytical data of the mercury levels in several fish and shellfish species to create awareness among individuals of the risks associated with consuming fish contaminated with mercury. Mercury concentrations varied from a mean of 0.02 mg/kg in Indian mackerel to 0.19 mg/kg in shark in both fresh and frozen fish, from 0.02 mg/kg in sardines to 0.18 mg/kg in skipjack tuna in canned fish, and from 0.02 mg/kg in Indian mackerel to 0.79 mg/kg in shark in dried fish. Shellfish contained a slightly higher amount of mercury than fresh or frozen fish with a mean of 0.09 mg/kg. Trophic position, followed by habitat, was the most important factors for variability in mercury concentrations in fish and shellfish. The maximum safe weekly intake (MSWI) values of mercury were significantly higher for herbivores than for carnivores. The MSWI value for total mercury in the case of consuming most (72%) fish species was more than 5 kg; however, the MSWI value was never more than 5 kg in most (66%) shellfish species. Risks were identified upon consumption of 120 g of dried shark when exceeding the provisional tolerable weekly intake threshold (1.6 ?g/kg) for methylmercury. Therefore, fish-eating populations should reduce the quantity of dried shark to efficiently diminish the exposure to mercury.

Al-Mughairi S; Yesudhason P; Al-Busaidi M; Al-Waili A; Al-Rahbi WA; Al-Mazrooei N; Al-Habsi SH

2013-07-01

 
 
 
 
281

Toxicity of melamine, an adulterant in fish feeds: experimental assessment of its effects on tilapia.  

UK PubMed Central (United Kingdom)

Unscrupulous inclusion of melamine in fish feeds can be harmful to fish and may be hazardous to human health. An eight-week feeding trial examined the effects of melamine (inclusion levels; 5-30 g kg?¹ feed) on the growth performance, feed efficiency, histopathological changes and melamine residues in sex-reversed red tilapia, Oreochromis niloticus (L.) × O.mossambicus (Peters). Fish which received melamine-containing feeds grew less, utilized feeds less efficiently and performed poorly, besides exhibiting defects such as fin erosion, anorexia, sluggish swimming behaviour, paling/darkening of skin and low survival. Melamine concentration in the fish reflected its inclusion level in the feeds, and the content was higher in the viscera than in the fish fillet or whole fish. Histopathological alterations were evident in the kidney, liver and gills of fish subjected to melamine treatment - the severity of lesions corresponded to its dosage. Enlargement of renal tubules was observed in the kidney of fish fed with ?10 g melamine kg?¹ feed, although, crystals were not deposited. Fish subjected to melamine insult had more prominent lesions in liver than in kidney. Toxic effects on the gills manifested as epithelial hyperplasia of the primary and secondary lamellae. The anomalies were severe at higher intake levels of melamine.

Phromkunthong W; Nuntapong N; Boonyaratpalin M; Kiron V

2013-06-01

282

The Rhine red, the fish dead-the 1986 Schweizerhalle disaster, a retrospect and long-term impact assessment.  

UK PubMed Central (United Kingdom)

BACKGROUND: The November 1, 1986 fire at a Sandoz Ltd. storehouse at Schweizerhalle, an industrial area near Basel, Switzerland, resulted in chemical contamination of the environment. The storehouse, which was completely destroyed by the fire, contained pesticides, solvents, dyes, and various raw and intermediate materials. The majority of the approximately 1,250 t of stored chemicals was destroyed in the fire, but large quantities were introduced into the atmosphere, into the Rhine River through runoff of the fire-fighting water, and into the soil and groundwater at the site. The chemicals discharged into the Rhine caused massive kills of benthic organisms and fish, particularly eels and salmonids. Public and private reaction to the fire and subsequent chemical spill was very strong. This happened only a few months after the Chernobyl accident and it destroyed the myth of immunity of Switzerland regarding such catastrophes. AIM: This article reviews the damaging events of November 1986 and aims at striking stock two decades later. RESULTS AND DISCUSSION: In the aftermath of this once-per-century accident, the aim was to obtain new knowledge for the environmental sciences and to achieve progress for water pollution control issues. The following themes are discussed: mitigation measures by the chemical industry and by the governmental authorities, activities of environmental protection organizations, chemical and biological monitoring, alert organization, ecological damages, ecotoxicological effects assessment, recovery and alteration of the river biology, return of the salmon, drinking water supplies, research programs, education of environmental scientists, and visions for the future. CONCLUSIONS: The catastrophic pollution of the Rhine in November 1986 has triggered by the openly visible damages of the river biology that subsequently significant progress was made towards the prevention of such environmental catastrophes. The crucial risk reduction measures in the chemical industry, legal regulations and controls as well as chemical and biological monitoring of the river water quality were substantially improved. Politics and chemical industry have learned their lectures and have proceeded accordingly. RECOMMENDATIONS: A drastic acute contamination, as it has happened at Schweizerhalle in 1986, is clearly recognizable by the toxic effects, which it is causing. This can lead to mitigation activities, which are positive considering a long-term perspective. However, the less obvious effects of chronic water pollution should receive more attention as well as the ongoing alteration of the biocenosis. A high water quality must be demanded for using water from the Rhine to produce drinking water. In that context, micropollutants should also be considered and particular attention should be payed to emerging contaminants. PERSPECTIVES: The big chemical storehouse fire of 1986 had an important impact on the transboundary cooperation and has improved the willingness for international cooperation. The fire catastrophe of Schweizerhalle has triggered many activities in particular for the Rhine River. Overall, the effects are positive on the basis of a long-term perspective. The applied whole basin approach gives an example on a global basis for other river systems, which still are more heavily polluted.

Giger W

2009-08-01

283

The Application of Traits-Based Assessment Approaches to Estimate the Effects of Hydroelectric Turbine Passage on Fish Populations  

Energy Technology Data Exchange (ETDEWEB)

One of the most important environmental issues facing the hydropower industry is the adverse impact of hydroelectric projects on downstream fish passage. Fish that migrate long distances as part of their life cycle include not only important diadromous species (such as salmon, shads, and eels) but also strictly freshwater species. The hydropower reservoirs that downstream-moving fish encounter differ greatly from free-flowing rivers. Many of the environmental changes that occur in a reservoir (altered water temperature and transparency, decreased flow velocities, increased predation) can reduce survival. Upon reaching the dam, downstream-migrating fish may suffer increased mortality as they pass through the turbines, spillways and other bypasses, or turbulent tailraces. Downstream from the dam, insufficient environmental flow releases may slow downstream fish passage rates or decrease survival. There is a need to refine our understanding of the relative importance of causative factors that contribute to turbine passage mortality (e.g., strike, pressure changes, turbulence) so that turbine design efforts can focus on mitigating the most damaging components. Further, present knowledge of the effectiveness of turbine improvements is based on studies of only a few species (mainly salmon and American shad). These data may not be representative of turbine passage effects for the hundreds of other fish species that are susceptible to downstream passage at hydroelectric projects. For example, there are over 900 species of fish in the United States. In Brazil there are an estimated 3,000 freshwater fish species, of which 30% are believed to be migratory (Viana et al. 2011). Worldwide, there are some 14,000 freshwater fish species (Magurran 2009), of which significant numbers are susceptible to hydropower impacts. By comparison, in a compilation of fish entrainment and turbine survival studies from over 100 hydroelectric projects in the United States, Winchell et al. (2000) found useful turbine passage survival data for only 30 species. Tests of advanced hydropower turbines have been limited to seven species - Chinook and coho salmon, rainbow trout, alewife, eel, smallmouth bass, and white sturgeon. We are investigating possible approaches for extending experimental results from the few tested fish species to predict turbine passage survival of other, untested species (Cada and Richmond 2011). In this report, we define the causes of injury and mortality to fish tested in laboratory and field studies, based on fish body shape and size, internal and external morphology, and physiology. We have begun to group the large numbers of unstudied species into a small number of categories, e.g., based on phylogenetic relationships or ecological similarities (guilds), so that subsequent studies of a few representative species (potentially including species-specific Biological Index Testing) would yield useful information about the overall fish community. This initial effort focused on modifying approaches that are used in the environmental toxicology field to estimate the toxicity of substances to untested species. Such techniques as the development of species sensitivity distributions (SSDs) and Interspecies Correlation Estimation (ICE) models rely on a considerable amount of data to establish the species-toxicity relationships that can be extended to other organisms. There are far fewer studies of turbine passage stresses from which to derive the turbine passage equivalent of LC{sub 50} values. Whereas the SSD and ICE approaches are useful analogues to predicting turbine passage injury and mortality, too few data are available to support their application without some form of modification or simplification. In this report we explore the potential application of a newer, related technique, the Traits-Based Assessment (TBA), to the prediction of downstream passage mortality at hydropower projects.

Cada, Glenn F [ORNL; Schweizer, Peter E [ORNL

2012-04-01

284

Causes and methods to estimate cryptic sources of fishing mortality(a.).  

UK PubMed Central (United Kingdom)

Cryptic, not readily detectable, components of fishing mortality are not routinely accounted for in fisheries management because of a lack of adequate data, and for some components, a lack of accurate estimation methods. Cryptic fishing mortalities can cause adverse ecological effects, are a source of wastage, reduce the sustainability of fishery resources and, when unaccounted for, can cause errors in stock assessments and population models. Sources of cryptic fishing mortality are (1) pre-catch losses, where catch dies from the fishing operation but is not brought onboard when the gear is retrieved, (2) ghost-fishing mortality by fishing gear that was abandoned, lost or discarded, (3) post-release mortality of catch that is retrieved and then released alive but later dies as a result of stress and injury sustained from the fishing interaction, (4) collateral mortalities indirectly caused by various ecological effects of fishing and (5) losses due to synergistic effects of multiple interacting sources of stress and injury from fishing operations, or from cumulative stress and injury caused by repeated sub-lethal interactions with fishing operations. To fill a gap in international guidance on best practices, causes and methods for estimating each component of cryptic fishing mortality are described, and considerations for their effective application are identified. Research priorities to fill gaps in understanding the causes and estimating cryptic mortality are highlighted.

Gilman E; Suuronen P; Hall M; Kennelly S

2013-10-01

285

Multibiomarker approach in fish to assess the impact of pollution in a large Brazilian river, Paraiba do Sul  

Energy Technology Data Exchange (ETDEWEB)

This article examines the advantages of the use of biomarkers as environmental indicators by applying it to Paraiba do Sul watershed, one of the most important Brazilian water bodies, which is in a critical environmental situation. We use a multibiomarker approach in fish as an integrated strategy to assess the impact of pollution. It comprehends a general biomarker of fish health, the condition factor (CF), and specific biomarkers of contaminant exposure such as metallothionein (MT), acetylcholinesterase (AChE) activity and biliary polycyclic aromatic hydrocarbons (PAH) metabolites. Our results revealed different effects in the fish from diverse locations with varying degrees of pollution. Furthermore, fish located just upstream of the water-treatment plant of the metropolitan area of Rio de Janeiro has shown to be affected by metals. This study indicates the usefulness of integrating a set of biomarkers to define the effects of anthropogenic inputs in aquatic bodies under complex polluted situations. - Integrated approach using biomarkers proofs suitable for environmental assessment of a diversely polluted river.

Linde-Arias, Ana Rosa [Laboratorio de Toxicologia, Centro de Estudos da Saude do Trabalhador e Ecologia Humana, Escola Nacional de Saude Publica Sergio Arouca, Fundacao Oswaldo Cruz, Leopoldo Bulhoes, 1480, Rio de Janeiro (Brazil)], E-mail: arlinde@ensp.fiocruz.br; Inacio, Alan F.; Novo, Leonardo A.; Alburquerque, Carla de; Moreira, Josino C. [Laboratorio de Toxicologia, Centro de Estudos da Saude do Trabalhador e Ecologia Humana, Escola Nacional de Saude Publica Sergio Arouca, Fundacao Oswaldo Cruz, Leopoldo Bulhoes, 1480, Rio de Janeiro (Brazil)

2008-12-15

286

Multibiomarker approach in fish to assess the impact of pollution in a large Brazilian river, Paraiba do Sul  

International Nuclear Information System (INIS)

This article examines the advantages of the use of biomarkers as environmental indicators by applying it to Paraiba do Sul watershed, one of the most important Brazilian water bodies, which is in a critical environmental situation. We use a multibiomarker approach in fish as an integrated strategy to assess the impact of pollution. It comprehends a general biomarker of fish health, the condition factor (CF), and specific biomarkers of contaminant exposure such as metallothionein (MT), acetylcholinesterase (AChE) activity and biliary polycyclic aromatic hydrocarbons (PAH) metabolites. Our results revealed different effects in the fish from diverse locations with varying degrees of pollution. Furthermore, fish located just upstream of the water-treatment plant of the metropolitan area of Rio de Janeiro has shown to be affected by metals. This study indicates the usefulness of integrating a set of biomarkers to define the effects of anthropogenic inputs in aquatic bodies under complex polluted situations. - Integrated approach using biomarkers proofs suitable for environmental assessment of a diversely polluted river.

2008-01-01

287

Risk assessment of aflatoxins B1 (AFB1) in corn arepas in Colombia and chemical risk assessment case study mercury in Fish  

International Nuclear Information System (INIS)

The power point presentation is about: Identify the pair substrate (corn, wheat and rice) - mycotoxin (DON, AFB1) higher risk for the Colombian population, based on the exposure assessment and mercury in freshwater fish from Colombia. This report answer some the following questions: what are the most consumed products in the country, which may create a risk for the Colombian population, what are the prevention and control recommendations to reduce potential contamination of the products selected, what are economic activities and their impact areas that contribute most to the incorporation of of mercury in freshwater fish from Colombia,what are the species that may pose greater accumulation of mercury and methylmercury identified , what is the risk associated with the consumption of the species, what are the preventive measures to minimize exposure from consumption of fish with mercury and methylmercury and possible intervention strategies

2013-01-01

288

Self-assessment of hearing status and risk of noise-induced hearing loss in workers in a rolling stock plant.  

UK PubMed Central (United Kingdom)

Noise measurements and questionnaire inquiries were carried out for 124 workers of a rolling stock plant to develop a hearing conservation program. On the basis of that data, the risk of noise-induced hearing loss (NIHL) was evaluated. Additionally, the workers' hearing ability was assessed with the (modified) Amsterdam inventory for auditory disability and handicap, (m)AIADH. The workers had been exposed to noise at A-weighted daily noise exposure levels of 74-110 dB for 1-40 years. Almost one third of the workers complained of hearing impairment and the (m)AIADH results showed some hearing difficulties in over half of them. The estimated risk of hearing loss over 25 dB in the frequency range of 3-6 kHz was 41-50% when the standard method of predicting NIHL specified in Standard No. ISO 1999:1990 was used. This risk increased to 50-67% when noise impulsiveness, coexposure to organic solvents, elevated blood pressure and smoking were included in calculations.

Pawlaczyk-?uszczy?ska M; Dudarewicz A; Zamojska M; Sliwinska-Kowalska M

2012-01-01

289

Self-assessment of hearing status and risk of noise-induced hearing loss in workers in a rolling stock plant.  

Science.gov (United States)

Noise measurements and questionnaire inquiries were carried out for 124 workers of a rolling stock plant to develop a hearing conservation program. On the basis of that data, the risk of noise-induced hearing loss (NIHL) was evaluated. Additionally, the workers' hearing ability was assessed with the (modified) Amsterdam inventory for auditory disability and handicap, (m)AIADH. The workers had been exposed to noise at A-weighted daily noise exposure levels of 74-110 dB for 1-40 years. Almost one third of the workers complained of hearing impairment and the (m)AIADH results showed some hearing difficulties in over half of them. The estimated risk of hearing loss over 25 dB in the frequency range of 3-6 kHz was 41-50% when the standard method of predicting NIHL specified in Standard No. ISO 1999:1990 was used. This risk increased to 50-67% when noise impulsiveness, coexposure to organic solvents, elevated blood pressure and smoking were included in calculations. PMID:22721544

Pawlaczyk-?uszczy?ska, Ma?gorzata; Dudarewicz, Adam; Zamojska, Ma?gorzata; Sliwinska-Kowalska, Mariola

2012-01-01

290

Disposable E-Tongue for the Assessment of Water Quality in Fish Tanks  

Directory of Open Access Journals (Sweden)

Full Text Available A disposable screen-printed e-tongue based on sensor array and pattern recognition that is suitable for the assessment of water quality in fish tanks is described. The characteristics of sensors fabricated using two kinds of sensing materials, namely (i) lipids (referred to as Type 1), and (ii) alternative electroactive materials comprising liquid ion-exchangers and macrocyclic compounds (Type 2) were evaluated for their performance stability, sensitivity and reproducibility. The Type 2 e-tongue was found to have better sensing performance in terms of sensitivity and reproducibility and was thus used for application studies. By using a pattern recognition tool i.e. principal component analysis (PCA), the e-tongue was able to discriminate the changes in the water quality in tilapia and catfish tanks monitored over eight days. E-tongues coupled with partial least squares (PLS) was used for the quantitative analysis of nitrate and ammonium ions in catfish tank water and good agreement were found with the ion-chromatography method (relative error, ±1.04- 4.10 %).

Chew-Cheen Chang; Bahruddin Saad; Misni Surif; Mohd Noor Ahmad; Ali Yeon Md Shakaff

2008-01-01

291

Fish acute toxicity syndromes and their use in the QSAR approach to hazard assessment  

Energy Technology Data Exchange (ETDEWEB)

Implementation of the Toxic Substances Control Act of 1977 creates the need to reliably establish testing priorities because laboratory resources are limited and the number of industrial chemicals requiring evaluation is overwhelming. The use of quantitative structure activity relationship (QSAR) models as rapid and predictive screening tools to select more potentially hazardous chemicals for in-depth laboratory evaluation has been proposed. Further implementation and refinement of quantitative structure-toxicity relationships in aqueous toxicology and hazard assessment requires the development of a mode-of-action database. With such a database, a qualitative structure-activity relationship can be formulated to assign the proper mode of action, and respective QSAR, to a given chemical structure. In this review, the development of fish acute toxicity syndromes (FATS), which are toxic-response sets based on various behavioral and physiological-biochemical measurements, and their projected use in the mode-of-action database are outlined. Using behavioral parameters monitored in the fathead minnow during acute toxicity testing, FATS associated with acetylcholinesterase (AChE) inhibitors and narcotics could be reliably predicted. However, compounds classified as oxidative phosphorylation uncouplers or stimulants could not be resolved. Refinement of this approach by using respiratory-cardiovascular responses in the rainbow trout, enabled FATS associated with AChE inhibitors, convulsants, narcotics, respiratory blockers, respiratory membrane irritants, and uncouplers to be correctly predicted.

McKim, J.M.; Bradbury, S.P.; Niemi, G.J.

1987-04-01

292

Monitoring concepts useful in the assessment of climate change effects on US fish and wildlife resources  

Energy Technology Data Exchange (ETDEWEB)

The objectives of this paper are to: (1) discuss the sensitivity of fish and wildlife resources and their habitats to climate changes as a basis for selecting indicators of climate change effects; (2) outline an anticipatory monitoring approach for trend assessment; and (3) identify regional and national challenges for management response to affected wildlife resources. It is important to note the fundamental differences between measuring meteorological and atmospheric parameters for the presence of global climatic changes and monitoring for their influence on a particular ecosystem. Measuring meteorological and atmospheric parameters of climate change is a relatively well defined problem that is based on three important elements: changes can be measured using existing techniques for observing standard meteorological parameters, data describing meteorological conditions are available in many cases in enough detail to develop baselines for the evaluation of trends, and global climate and circulation models, while limited in many respects, provide a solid conceptual framework that is capable of generating testable hypotheses about the direction and magnitude of anticipated changes. 9 refs.

Breckenridge, R.P.; Otis, M.D.

1988-01-01

293

PREVALENCE OF ESCHERICHIA COLI IN FOOD FISHES ASSESSED FROM DOMESTIC RETAIL FISH MARKET, GUNTUR CITY, ANDHRA PRADESH, INDIA: A CASE STUDY  

Directory of Open Access Journals (Sweden)

Full Text Available The prevalence of Escherichia coli in fin fish and shell fish samples collected from domestic retail fish market, Guntur City, Andhra Pradesh, India. Domestic fish markets in India are poorly maintained hygienic conditions and are prone to several microbiological pathogens which in turn lead to spread of food safety illness such asdiarrhea etc. Most of the low income group people access their food fishes from the local fish markets. Studied over a period of one Year (November 2009 - December 2010). Of the different freshwater, brakishwater, marinewater fin fishes and shell fishes were analyzed, the highest incidence of Escherichia coli was seen in freshwater fishes, (79.76%) followed by the brakishwater fishes (78.84%). Among the crustaceans (95.2%) showed the highest incidence followed by Macrobrachium rosenbargii (54.16%). Both fin fishes and crustaceans the incidence of Escherichia coli was seen in crustaceans. A well marked seasonal variation in the incidence pattern was observed in both fin fishes and crustaceans with higher incidence during monsoon season fallowed by post-monsoon and pre-monsoon. Results were revealed that the E.coli loads remained higher in Macrobrachium rosenbargii than other finfish and shellfishes. The fishes were contaminated with E.coli indicating poor hygiene and sanitary condition in domestic fish market. The percentages of the prevallance of E.coli were compared to seasonal variation highest in monsoon.

BUJJAMMA POLIMETLA; SUMANTH KUMAR KUNDA

2013-01-01

294

Assessment of committed effective dose due to consumption of Red Sea coral reef fishes collected from the local market (Sudan)  

International Nuclear Information System (INIS)

[en] An assessment of committed effective dose (CED) due to consumption of Red Sea fish containing ''2''1''0Po and ''1''3''7Cs was performed for 23 different marine fish samples collected from the local market at Port Sudan. The fish were classified according to their feeding habits into three categories: carnivores, herbivores, and omnivores. Measured activity concentrations of 2''1''0Po were found in the ranges 0.25-6.42 (carnivores), 0.7- 5 (omnivores) and 1.5-3.8 (herbivores) Bq/kg fresh weight. In the same study, activity concentrations of Cs-137 were determined to be in the ranges 0.1-0.46 (carnivores), 0.09-0.35 (omnivores) and 0.09-0.32 (herbivores) Bq/kg fresh weigh, which were several times lower than those of ''2''1''0Po. Appropriate conversion factors were used to derive the CED, which was found to be 0.012, 0.01 and 0.01 (?Sv/Yr) in carnivores, omnivores and herbivores, respectively, for ''1'''3''7Cs. This contributes about 0.4% of the total dose exclusively by ingestion of fish. For ''2''1''0Po, it was found to be 3.47, 4.81and 4.14 (?Sv/Yr) in carnivores, omnivores and herbivores, respectively, which represents 99.6% of the total dose (exclusively by ingestion of fish ). The results of CED calculations suggest that the dose received by the Sudanese population from the consumption of marine fish is rather small and that the contribution of ''1''3''7Cs is negligible compared to ''2''1''0Po.(Author)

2008-01-01

295

Assessment of Committed Effective Dose due to consumption of Red Sea coral reef fishes collected from the local market (Sudan)  

Energy Technology Data Exchange (ETDEWEB)

An assessment of Committed Effective Dose (CED) due to consumption of Red Sea fish containing {sup 210}Po and {sup 137}Cs was performed for 23 different marine fish samples collected from the local market at Port Sudan. The fish were classified according to their feeding habits into three categories: carnivores, herbivores, and omnivores. Measured activity concentrations of {sup 210}Po were found in the ranges 0.25-6.42 (carnivores), 0.7-5 (omnivores) and 1.5-3.8 (herbivores) Bq/kg fresh weight. In the same study, activity concentrations of Cs-137 were determined to be in the ranges 0.1-0.46 (carnivores), 0.09-0.35 (omnivores) and 0.09-0.32 (herbivores) Bq/kg fresh weight, which were several times lower than those of {sup 210}Po. Appropriate conversion factors were used to derive the CED, which was found to be 0.012, 0.01 and 0.01 ({mu}Sv/yr) in carnivores, omnivores and herbivores, respectively, for {sup 137}Cs. This contributes about 0.4% of the total dose exclusively by ingestion of fish. For {sup 210}Po, it was found to be 3.47, 4.81 and 4.14 ({mu}Sv/yr) in carnivores, omnivores and herbivores, respectively, which represents 99.6% of the total dose (exclusively by ingestion of fish). The results of CED calculations suggest that the dose received by the Sudanese population from the consumption of marine fish is rather small and that the contribution of {sup 137}Cs is negligible compared to {sup 210}Po.

Hassona, Rifaat K. [Sudan Atomic Energy Commission, Khartoum, P.O. Box 3001 (Sudan)], E-mail: rifaatk@yahoo.com; Sam, A.K. [Sudan Atomic Energy Commission, Khartoum, P.O. Box 3001 (Sudan); Osman, O.I. [Chemistry Department, Faculty of Science, University of Khartoum (Sudan); Sirelkhatim, D.A. [Sudan Atomic Energy Commission, Khartoum, P.O. Box 3001 (Sudan); LaRosa, J. [Formerly at IAEA Marine Environment Laboratory, 4 Quai Antoine 1er, MC 98000 (Monaco)

2008-04-15

296

Assessment of Committed Effective Dose due to consumption of Red Sea coral reef fishes collected from the local market (Sudan)  

International Nuclear Information System (INIS)

[en] An assessment of Committed Effective Dose (CED) due to consumption of Red Sea fish containing 210Po and 137Cs was performed for 23 different marine fish samples collected from the local market at Port Sudan. The fish were classified according to their feeding habits into three categories: carnivores, herbivores, and omnivores. Measured activity concentrations of 210Po were found in the ranges 0.25-6.42 (carnivores), 0.7-5 (omnivores) and 1.5-3.8 (herbivores) Bq/kg fresh weight. In the same study, activity concentrations of Cs-137 were determined to be in the ranges 0.1-0.46 (carnivores), 0.09-0.35 (omnivores) and 0.09-0.32 (herbivores) Bq/kg fresh weight, which were several times lower than those of 210Po. Appropriate conversion factors were used to derive the CED, which was found to be 0.012, 0.01 and 0.01 (?Sv/yr) in carnivores, omnivores and herbivores, respectively, for 137Cs. This contributes about 0.4% of the total dose exclusively by ingestion of fish. For 210Po, it was found to be 3.47, 4.81 and 4.14 (?Sv/yr) in carnivores, omnivores and herbivores, respectively, which represents 99.6% of the total dose (exclusively by ingestion of fish). The results of CED calculations suggest that the dose received by the Sudanese population from the consumption of marine fish is rather small and that the contribution of 137Cs is negligible compared to 210Po

2008-04-15

297

Population-level assessments should be emphasized over community/ecosystem-level assessments. Environmental Sciences Division Publication No. 1535. [Concerning the impact of power plants on fish populations  

Energy Technology Data Exchange (ETDEWEB)

Arguments are presented in favor of emphasizing population-level assessments over community/ecosystem-level assessments. The two approaches are compared on each of four issues: (1) the nature of entrainment/impingement impacts; (2) the ability to forecast reliably for a single fish population as contrasted to the ability to forecast for an aquatic community or ecosystem; (3) practical considerations involving money, manpower, time, and the need to make decisions; and (4) the nature of societal and economic concerns. The conclusion on each of these four issues is that population-level assessments provide the optimal approach for evaluating the effects of entrainment and impingement mortality.

Van Winkle, W.

1980-01-01

298

Fish Passage Assessment of an Advanced Hydropower Turbine and Conventional Turbine Using Blade-Strike Modeling  

Directory of Open Access Journals (Sweden)

Full Text Available Hydropower is the largest renewable energy source in the world. However, in the Columbia and Snake River basins, several species of Pacific salmon and steelhead have been listed for protection under the Endangered Species Act due to significant declines of fish population. Dam operators and design engineers are thus faced with the task of making hydroelectric facilities more fish friendly through changes in hydro-turbine design and operation. Public Utility District No. 2 of Grant County, Washington, applied for relicensing from the U.S. Federal Energy Regulatory Commission to replace the 10 turbines at Wanapum Dam with advanced hydropower turbines that were designed to increase power generation and improve fish passage conditions. We applied both deterministic and stochastic blade-strike models to compare fish passage performance of the newly installed advanced turbine to an existing turbine. Modeled probabilities were compared to the results of a large-scale live-fish survival study and a Sensor Fish study under the same operational parameters. Overall, injury rates predicted by the deterministic model were higher than experimental rates of injury, while those predicted by the stochastic model were in close agreement with experimental results. Fish orientation at the time of entry into the plane of the leading edges of the turbine runner blades was an important factor contributing to uncertainty in modeled results. The advanced design turbine had slightly higher modeled injury rates than the existing turbine design; however, no statistical evidence suggested significant differences in blade-strike injuries between the two turbines, thus the hypothesis that direct fish survival rate through the advanced hydropower turbine is equal to or higher than that for fish passing through the conventional turbine could not be rejected.

Zhiqun Deng; Thomas J. Carlson; Dennis D. Dauble; Gene R. Ploskey

2011-01-01

299

Assessing genetic diversity of Brazilian reef fishes by chromosomal and DNA markers.  

Science.gov (United States)

Little is known on genetics of Brazilian coral reef fish and most of this information is limited to chromosome characterization of major representative species. The diploid chromosome number in marine fish varies from 2n= 22-26 to 2n = 240-260. Despite of this apparent diversity, most studied marine species have a diploid complement with 48 acrocentric chromosomes. This latter trend is mostly observed among Perciformes, an important major taxon of coral reef fishes. Studies in the families Pomacentridae, Pomacanthidae and Chaetodontidae, for example, have shown a common karyotype pattern entirely formed by 48 uniarmed chromosomes. However, rare numerical and structural chromosome polymorphisms and cryptic chromosome rearrangements involving heterochromatin segments and/or nucleolar organizing sites have been reported among such fishes. Although new chromosome forms can contribute to the establishment of genetically isolated populations, their role in reef fish speciation at marine realm still is an open question. More recently, genomic DNA analyses using RAPD and microsatellites, and sequencing and RFLP of mitochondrial DNA have increasingly been used in Atlantic reef fish species. Genetic homogeneity over wide geographical ranges has been reported for different fish groups, in contrast to several cases of population substructuring related to environmental constraints or evolutionary history. Amazonas outflow and upwelling on the Southeastern coast of Brazil are believed to be strong barriers to dispersal of some reef species. Moreover, it is suggested that the pattern of speciation and population structure at South Atlantic is quite distinctive from Pacific Ocean, even when comparing closely related taxa. Further genetic studies are strongly encouraged in Brazilian reef fishes in order to provide a reliable scenario of the genetic structure in this important and diverse fish group. PMID:16502093

Galetti, Pedro Manoel; Molina, Wagner Franco; Affonso, Paulo Roberto A M; Aguilar, Cecília Teixeira

2006-01-01

300

Natural Propagation and Habitat Improvement, Washington, Volume IIA, Tumwater Falls and Dryden Dam Fish Passage, 1983 Final Report.  

Energy Technology Data Exchange (ETDEWEB)

This engineering feasibility and predesign report on the Tumwater Falls and Dryden Dam Fish Passage Project provides BPA with information for planning purposes and will serve as a discussion document for interested agencies. Tumwater Falls and Dryden Dams, both on the Wenatchee River, were built in the early 1900's as diversions for hydropower, and irrigation and hydropower, respectively. The present fishway facilities at both sites are inadequate to properly pass the anadromous fish runs in the Wenatchee River. These runs include spring and summer chinook salmon, sockeye salmon, coho salmon and steelhead trout. Predesign level drawings are provided in this report that represent fishway schemes capable of adequately passing present and projected fish runs. The effects of present passage facilities on anadromous fish stocks is addressed both quantitatively and qualitatively. The quantitative treatment assesses losses of adult migrants due to the structures and places an estimated value on those fish. The dollar figure is estimated to be between $391,000 and $701,000 per year for both structures. The qualitative approach to benefits deals with the concept of stock vigor, the need for passage improvements to help ensure the health of the anadromous fish stock. 29 references, 27 figures, 5 tables.

Unknown Author

1984-05-01

 
 
 
 
301

A simple and effective digital imaging approach for tuna fish length measurement compatible with fishing operations  

UK PubMed Central (United Kingdom)

Fish length measurement of commercial catches is an important data input to many fish stock assessments to appraise stock status and to provide management advice for sustainable fisheries. However, as the process of measurement is usually laborious or complex, it is difficult to operate on longline fishing vessels on deck. This study proposes an effective technique for measuring a tuna's snout to fork length (SNFL) in digital images or photographs taken on the deck of tuna fishing vessels by observers using hand-held camera. Photographic factors, such as direction angle, top-view angle, and distance to fish body were examined in terms of estimation error. Hough transform (HT) and projective transform (PT) were applied to conduct line detection in automatic mode and to correct for projective distortion of the fish images, respectively. Experimental results showed that the estimation error was within 5% when the image was taken with a direction angle of 315-0° or 135-225°, and with a top-view angle of more than 45°. The PT correction reduced the estimation error especially in small top-view angle samples, with an average improvement of 64% and 48% in manual mode and in automatic mode, respectively. The proposed method was validated with the results showing that, after 30min of practice, an operator can successfully make a measurement within a minute while the average (±std. dev.) estimation error was 4.5±4.4% using the developed software program. With slight modification, the developed approach could be adapted to various applications concerning size measurement of plants or animals using photometric approach.

Hsieh Ching-Lu; Chang Hsiang-Yun; Chen Fei-Hung; Liou Jhao-Huei; Chang Shui-Kai; Lin Ta-Te

2011-01-01

302

Assessing the use of existing data to compare plains fish assemblages collected from random and fixed sites in Colorado  

Science.gov (United States)

The U.S. Geological Survey, in cooperation with Colorado Parks and Wildlife, assessed the potential use of combining recently (2007 to 2010) and formerly (1992 to 1996) collected data to compare plains fish assemblages sampled from random and fixed sites located in the South Platte and Arkansas River Basins in Colorado. The first step was to determine if fish assemblages collected between 1992 and 1996 were comparable to samples collected at the same sites between 2007 and 2010. If samples from the two time periods were comparable, then it was considered reasonable that the combined time-period data could be used to make comparisons between random and fixed sites. In contrast, if differences were found between the two time periods, then it was considered unreasonable to use these data to make comparisons between random and fixed sites. One-hundred samples collected during the 1990s and 2000s from 50 sites dispersed among 19 streams in both basins were compiled from a database maintained by Colorado Parks and Wildlife. Nonparametric multivariate two-way analysis of similarities was used to test for fish-assemblage differences between time periods while accounting for stream-to-stream differences. Results indicated relatively weak but significant time-period differences in fish assemblages. Weak time-period differences in this case possibly were related to changes in fish assemblages associated with environmental factors; however, it is difficult to separate other possible explanations such as limited replication of paired time-period samples in many of the streams or perhaps differences in sampling efficiency and effort between the time periods. Regardless, using the 1990s data to fill data gaps to compare random and fixed-site fish-assemblage data is ill advised based on the significant separation in fish assemblages between time periods and the inability to determine conclusive explanations for these results. These findings indicated that additional sampling will be necessary before unbiased comparisons can be made between fish assemblages collected from random and fixed sites in the South Platte and Arkansas River Basins.

Zuellig, Robert E.; Crockett, Harry J.

2013-01-01

303

ASSESSMENT METHODS OF CORMORANT (Phalacrocorax carbo) DIET  

Directory of Open Access Journals (Sweden)

Full Text Available Various cormorant diet assessment methods are used to assess their daily meal in order to evaluate, using these and other data, the damage to commercial fish farms as well as the damage on open waters caused by cormorants. All of the parameters used for evaluating the damage to fish stock (number of birds, density and fish structure, daily meal, fish price, degree of protection and preservation etc.) are specific for an individual fishpond or other body of water and can only be used for that locality and not elsewhere. The results on the lowest and highest values of fish mass that cormorants eat daily vary extensively. By examining the available literature, the following values for individual adults have been determined: pellets — 347 g, pellets of captive cormorants — 371 g, stomach content — 359.5 g, regurgitations — 260 to 539 g, energy requirements — 751 g, stomach temperature — 336±98 g.

Krešimir Terzi?; An?elko Opa?ak; Dinko Jelki?; Tihomir Florijan?i?

2008-01-01

304

Assessment of ascending capacity of migratory fish in fishways by eco-hydraulic experiments (I) - Baffled fishways  

Energy Technology Data Exchange (ETDEWEB)

This paper presents an echo-hydraulic experimental approach to assessment of ascending capacity of migratory fish in a baffled fishways. Sweetfish, Plecoglossus altivelis, trout, Oncorhynchus mykiss, are used in these experiments. Ascending environment of the migratory fish in rivers is analyzed through the results of eco-hydraulic experiments. Important factors affecting the ascending capacity of migratory fish in baffled fishways are the discharge and slope of fishways and the fall height between the fishways entrance and the river bed. In these fishways the migratory capacity of sweetfish for a given fishways discharge is mainly affected by fishways slope, whereas the ascending capacity of trout for a given fishways slope was influenced by the change of fishways discharge. Loss of ascending properties of landlocked salmon, Oncorhynchus masou var ishikawai, was confirmed by these experiments. An ascending hydraulic criteria of the baffled fishways is defined by means of dimensionless factor F{sub f} and falling head H{sub f}. Ascending capacity of migratory fish in existing baffled fishways in river of eastern coastal region is poor because the slope of fishways is very steep. (author). 11 refs., 7 tabs., 8 figs.

Park, Sang-Deog [Kangnung National University, Kangnung(Korea)

2001-08-31

305

Assessment of metal status in drainage canal water and their bioaccumulation in Oreochromis niloticus fish in relation to human health.  

UK PubMed Central (United Kingdom)

The purpose of this study was to assess metal concentrations (Al, Cd, Pb, Hg and Ni) in Sabal drainage canal (Al-Menoufiya Province, River Nile Delta, Egypt) water as well as their accumulation in some selected organs (skin, muscles and kidneys) of Oreochromis niloticus fish to evaluate their hazard levels in relation to the maximum residual limits for human consumption. Drainage canal water was found to be heavily polluted with metals which far exceeded the permissible limits. It was found that metals accumulated in organs of O. niloticus in concentrations higher than those of canal water. Kidneys of O. niloticus contained the highest concentrations of the detected metals, while skin appeared to be the least preferred site for the bioaccumulation of metals as the lowest metals concentrations were detected in this tissue. The present study shows that fish organs contained high levels of metals exceeding the permissible limits values. Metals in muscle of fish were higher than the maximum permissible concentrations for human consumption. Thus, consuming fish caught from drainage canals is harmful to the consumers.

Authman MM; Abbas HH; Abbas WT

2013-01-01

306

Assessment of metal status in drainage canal water and their bioaccumulation in Oreochromis niloticus fish in relation to human health.  

Science.gov (United States)

The purpose of this study was to assess metal concentrations (Al, Cd, Pb, Hg and Ni) in Sabal drainage canal (Al-Menoufiya Province, River Nile Delta, Egypt) water as well as their accumulation in some selected organs (skin, muscles and kidneys) of Oreochromis niloticus fish to evaluate their hazard levels in relation to the maximum residual limits for human consumption. Drainage canal water was found to be heavily polluted with metals which far exceeded the permissible limits. It was found that metals accumulated in organs of O. niloticus in concentrations higher than those of canal water. Kidneys of O. niloticus contained the highest concentrations of the detected metals, while skin appeared to be the least preferred site for the bioaccumulation of metals as the lowest metals concentrations were detected in this tissue. The present study shows that fish organs contained high levels of metals exceeding the permissible limits values. Metals in muscle of fish were higher than the maximum permissible concentrations for human consumption. Thus, consuming fish caught from drainage canals is harmful to the consumers. PMID:22451326

Authman, Mohammad M N; Abbas, Hossam H; Abbas, Wafaa T

2012-03-27

307

Assessment of metals in fish from Lake Macquarie, New South Wales, Australia.  

UK PubMed Central (United Kingdom)

The concentrations of the metals cadmium, copper, mercury, lead, silver, selenium and zinc were measured in the muscle and gonad tissues of five species of fish, yellowfin bream (Acanthopagrus australis), silverbiddy (Gerres subfasciatus) and trumpeter whiting (Sillago maculata), southern log finned goby (Favonigobious lateralis), and the halfbridled goby (Arenigobius frenatus) from the contaminated Lake Macquarie NSW and three relatively uncontaminated reference estuaries, Wallis Lake, Port Stephens, and St. Georges Basin NSW. Fish from Lake Macquarie were found to have elevated concentrations of selenium, lead, cadmium, and zinc in one or both of these tissues in these species. Increased concentrations relative to background concentrations were most often observed at Cockle Bay, the site with the highest concentrations of these metals in sediments. The degree to which fish accumulated metals appeared to be related to life history characteristics of the species, with sediment-dwelling fish showing the greatest propensity to accumulate metals.

Roach AC; Maher W; Krikowa F

2008-02-01

308

SMALL FISH MODELS FOR IDENTIFYING AND ASSESSING THE EFFECTS OF ENDOCRINE DISRUPTING CHEMICALS  

Science.gov (United States)

Endocrine-disrupting chemicals (EDCs), in particular those which affect the hypothalamic-pituitary-gonadal (HPG) axis of vertebrates, have become a focus of regulatory screening and testing throughout the world. Small fish species, principally the fathead minnow (Pimephales prom...

309

Monitoring Concepts Useful in the Assessment of Climate Change Effects on US Fish and Wildlife Resources.  

Science.gov (United States)

The objectives of this paper are to: (1) discuss the sensitivity of fish and wildlife resources and their habitats to climate changes as a basis for selecting indicators of climate change effects; (2) outline an anticipatory monitoring approach for trend ...

R. P. Breckenridge M. D. Otis

1988-01-01

310

Assessment of Trace Metal Composition in Fish Samples from Nworie River  

Directory of Open Access Journals (Sweden)

Full Text Available This investigation surveyed heavy metal content of fish samples from Nworie river. The elements studied were Pb, Fe, Cd, Mn, Hg, Cu and Zn. The fish samples were collected from different locations in the river. The fish samples were analyzed for heavy metals using Atomic Absorption Spectrophotometer (AAS). The elemental toxicants Fe, Cd, Mn were identified in fresh fish specie Tilapia guineensis of mean values 3.275, 0.048 and 0.103 ppm, respectively, whereas Pb was below detection level. The analysis also shows Cu and Zn level of mean values 1.247 ppm and 3.241 ppm in Tilapia guineensis respectively. Also Hg was below detection level in Tilapia guineensis. The analysis of frozen fish samples purchased from Ekeonunwa market located 3 km from the river shows Pb, Fe and Cd levels of mean values 0.50, 4.73 and 0.05 ppm respectively. Also frozen fish analysis shows concentration of Mn, Hg, Cu and Zn of mean values 11.82, 0.0083, 8.00 and 1.02 ppm, respectively. There are three institutions that discharge untreated waste products into Nworie river. In view of this, there is need to determine the level of contamination of the river, since the inhabitants depend on the river for fishing and other domestic uses. This study is aimed at determining the level of heavy metal contaminants in fish samples from Nworie river. The effects of these elemental toxicants and the associated health hazards were examined.

I.J. Alinnor; I.A. Obiji

2010-01-01

311

Ecological risk assessment in a large river-reservoir. 6: Bioindicators of fish population health  

International Nuclear Information System (INIS)

Spatial distribution of contaminants in the sediments and biota of a large reservoir ecosystem were related to a variety of biological responses in fish populations and communities to determine possible relationships between contaminant loading in the environment and fish health. Much of the contaminant inventory in the Clinch River/Watts Bar Reservoir (CR/WBR) system has originated from three US Department of Energy facilities on the Oak Ridge Reservation, which borders this system in its upper reaches. Fish sampled from areas of the CR/WBR system with the highest levels of contaminants in the sediments and biota, primarily mercury and PCBs, had the most dramatic bioindicator responses. The major changes observed were induction of detoxification enzymes, organ dysfunction, increased frequency of histopathological lesions, impaired reproduction, and reduced fish community integrity. Mercury, the dominant contaminant, displayed a decreasing concentration gradient from the upper reaches of Poplar Creek to the lower Clinch River, which was consistent with a downstream gradient in several of the biological responses. A multivariate analysis using all of the individual fish health responses at each site in a discriminant analysis procedure also revealed a downstream gradient in integrated fish health. In Poplar Creek where contaminant concentrations were the highest, statistical correlations were observed between individual bioindicator responses such as contaminant exposure indicators, organ dysfunction, histopathological damage, and reproductive impairment. Relationships between contaminant loading and fish community indices such as species richness and relative abundance, however, were more difficult to establish in Poplar Creek because of the possible dominating influence of food and habitat availability on fish community dynamics. Using a suite of bioindicators that encompass a range of levels of biological organization and response-sensitivity scales improves the probability of identifying cause and effect and helps in distinguishing between natural and anthropogenic sources of stress in aquatic ecosystems

1999-01-01

312

A histology-based fish health assessment of the tigerfish, Hydrocynus vittatus from a DDT-affected area  

Science.gov (United States)

The Pongolapoort Dam (PPD) in the Phongola River, Kwa-Zulu Natal, South Africa and the surrounding area are classified as intermediate to low risk malaria areas and are continually being treated with DDT for malaria vector control. DDT is known as an endocrine disrupting chemical posing estrogenic and anti-androgenic properties and therefore might impact on the health of the 18 freshwater fish species found within this system. Of these species the tigerfish, Hydrocynus vittatus, is targeted by both recreational and local subsistence fishermen and was recently included in the South African threatened or protected species list. Their protected status and importance as a food source therefore emphasises the need for their health status elucidation. Previous research on H. vittatus in the Phongola floodplain highlighted DDT biomagnification in this species. Recent data show that the sum of the DDT levels in February 2009 (5403.9 ng/g lipid) and July 2009 (5537.4 ng/g lipid) is still comparable to the high levels found 30 years earlier. The aim of the current study was thus to determine the health status of H. vittatus in relation to DDT exposure by means of a histology-based fish health assessment protocol. Tigerfish were collected in February 2009 (n = 30) and July 2009 (n = 15) and gill, kidney and liver tissue were subjected to histological analyses. Mean Index values showed that the Kidney Index (IK), Gill Index (IG) and Fish Index (IFISH) were higher in fish from the February survey while the Liver Index was higher in those collected during July. Liver alterations identified included intercellular oedema, granular degeneration, vacuolation, nuclear pleomorphism and lymphocyte infiltration. Kidney alterations included dilation of the glomerulus capillaries, vacuolation and hyaline droplet degeneration. Gill alterations identified included telangiectasia and hyperplasia of the secondary lamella, congestion, and rupture of pillar cells. Although histological alterations were observed, the histology based fish health assessment protocol indicated that the H. vittatus population in PPD were in a healthy state. The histological assessment did not reflect the DDT exposure induced effects that were anticipated. However, the biomagnification effects in other tertiary consumers in the PPD such as crocodiles and fish eagles cannot be ruled out.

McHugh, K. J.; Smit, N. J.; van Vuren, J. H. J.; van Dyk, J. C.; Bervoets, L.; Covaci, A.; Wepener, V.

313

Quality loss assessment in fish-based ready-to-eat foods during refrigerated storage  

Directory of Open Access Journals (Sweden)

Full Text Available The present research addresses the quality loss in two different ready-to-eat (RTE) seafoods. With this aim, chemical and microbiological parameters were measured in tuna lasagne (TL) and hake roe foods which were refrigerated (4°C) for up to 35 and 71 days, respectively. Both foods showed a significant lipid oxidation (peroxide and interaction compound formation) development with storage time, which was especially marked in the case of the TL product, which also underwent an important lipid hydrolysis development. Both RTE products showed a low microbial development, no matter how much time had elapsed since the expiration dates; thus, low total viable count scores and volatile amine formation were attained while the presence of pathogen microorganisms was not detected. In view of the current increasing consumer demand for high quality refrigerated foods, the assessment of lipid damage related to nutritional and sensory values is recommended when fish-based RTE products are encountered.Se estudió la pérdida de calidad de dos productos marinos elaborados (lasaña de atún, TL; huevas de merluza) conservados en refrigeración (4 °C) durante 35 y 71 días, respectivamente. Ambos alimentos mostraron un desarrollo importante de la oxidación lipídica (formación de peróxidos y compuestos de interacción) durante el periodo de conservación, siendo mayor en el caso de TL; asimismo, el producto TL experimentó un importante desarrollo de hidrólisis lipídica. Sin embargo, ambos alimentos experimentaron un desarrollo bajo en microorganismos mesófilos y aminas volátiles; por otra parte, no maniferstaron presencia de microorganismos patógenos a lo largo del periodo de conservación, a pesar de sobrepasar el tiempo de caducidad. De acuerdo con la creciente demanda de nuevas preparaciones de alimentos refrigerados de calidad alta, se recomienda el estudio de las alteraciones lipídicas en elaboraciones basadas en alimentos de origen marino debido a su fuerte relación con la pérdida de calidades sensorial y nutricional.

Pourashouri, P.; Chapela, M. J.; Atanassova, M.; Cabado, A. G.; Vieites, J. M.; Aubourg, S. P.

2013-01-01

314

Genetic enetic characterization of curimba (“Prochilodus lineatus”) stocks used in stock enhancement programs Caracterização genética de estoques de curimba ("Prochilodus lineatus") utilizados em programas de repovoamento  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The aim with this study was to determine the genetic diversity of P. lineatus stocks, destined to stocking programs, with the RAPD molecular marker (Random Amplified Polymorphic DNA). Fifty two broodstocks of two fish farmings located at Salto Grande - SP (A) and Palotina - PR (B) counties and 32 ju...

Taís da Silva Lopes; Ricardo Pereira Ribeiro; Nelson Mauricio Lopera Barrero; Rodolfo Nardez Sirol; Jayme Aparecido Povh

315

Assessment of NMYC amplification: a comparison of FISH, quantitative PCR monoplexing and traditional blotting methods used with formalin-fixed, paraffin-embedded neuroblastomas.  

UK PubMed Central (United Kingdom)

OBJECTIVE: To determine the degree of agreement between fluorescence in situ hybridization (FISH), Southern blot analysis and LightCycler monoplex polymerase chain reaction (PCR) analysis in the assessment of NMYC gene amplification status in neuroblastoma. STUDY DESIGN: We performed a retrospective analysis of NMYC amplification, using FISH, LightCycler monoplex PCR and Southern blot techniques to assess NMYC amplification in a series of 18 neuroblastomas and 20 histologically normal tissues (15 lymph nodes, 2 pancreas specimens, 1 section each of thyroid, prostate and uterus). RESULTS: Nine neuroblastomas were NMYC amplified, and the remaining cases were nonamplified. All cases yielded interpretable results by Southern blotting and PCR monoplexing techniques. A single case of neuroblastoma was difficult to interpret by FISH due to high background debris. A single case demonstrated low-level NMYC amplification by LightCycler PCR monoplexing but was nonamplified by the other 2 techniques. FISH analysis in 1 case showed amplification, while the other 2 techniques demonstrated nonamplified status. The case in which FISH analysis incorrectly demonstrated amplification was the same one in which there was high background debris. The Southern blot results were reported as amplified or nonamplified, while numeric amplification ratios were obtained by both FISH and PCR LightCycler monoplex analysis. Comparison of these techniques demonstrated FISH to underestimate the degree of amplification in cases in which the amplification level was high by PCR. In fact, FISH appeared to saturate at amplification ratios > 10. CONCLUSION: The study revealed a high level of concordance between the 3 techniques for assessment of NMYC amplification status. However, FISH analysis has the advantage of allowing concurrent assessment of NMYC amplification status and architecture. LightCycler PCR monoplexing appears to have the advantage of more accurately quantitating high levels of NMYC amplification, including those amplified 20-fold or higher. Both FISH and PCR LightCycler monoplexing have the advantage of being performable on formalin-fixed, paraffin-embedded tissue.

Layfield LJ; Willmore-Payne C; Shimada H; Holden JA

2005-02-01

316

Refugia of marine fish in the Northeast Atlantic during the Last Glacial Maximum: concordant assessment from archaeozoology and palaeotemperature reconstructions  

Directory of Open Access Journals (Sweden)

Full Text Available Archaeozoological finds of the remains of marine and amphihaline fish from the Last Glacial Maximum (LGM) ca. 21 ka ago show evidence of very different species ranges compared to the present. We show how an ecological niche model (ENM) based on palaeoclimatic reconstructions of sea surface temperature and bathymetry can be used to effectively predict the spatial range of marine fish during the LGM. The results indicate that the ranges of marine fish species that are now in Northwestern Europe were almost completely displaced southward from the modern distribution. Significantly, there is strong evidence that there was an invasion of fish of current economic importance into the Western Mediterranean through the Straits of Gibraltar, where they were exploited by Palaeolithic human populations. There has been much recent interest in the marine glacial refugia to understand how the ranges of the economically important fish species will be displaced with the future climate warming. Recent ENM studies have suggested that species ranges may not have been displaced far southward during the coldest conditions of the LGM. However, archaeozoological evidence and LGM ocean temperature reconstructions indicate that there were large range changes, and certain marine species were able invade the Western Mediterranean. These findings are important for ongoing studies of molecular ecology that aim to assess marine glacial refugia from the genetic structure of living populations, and they pose questions about the genetic identity of vanished marine populations during the LGM. The research presents a challenge for future archaeozoological work to verify palaeoclimatic reconstructions and delimit the glacial refugia.

A. J. Kettle; A. Morales-Muñiz; E. Roselló-Izquierdo; D. Heinrich; L. A. Vøllestad

2010-01-01

317

Toxic impact of two organophosphate insecticides on biochemical parameters of a food fish and assessment of recovery response.  

Science.gov (United States)

Sublethal effects of chlorpyrifos (CPF) and monocrotophos (MCP) on fish biochemical constituents were investigated along with the assessment of recovery response after cessation of intoxication. The fish, Clarias batrachus were exposed to 1.656 mg(-l) and 2.114 mg(-l) of CPF and MCP for 28 days. After 28 days, they were released in freshwater and allowed to recover for 21 days. The CPF exposure resulted in the decrease of carbohydrate and glycogen content, whereas MCP intoxication caused mixed response. Pyruvate and lactate contents were altered under the stress of CPF and MCP. Recovery of these alterations was observed after the cessation of toxicity. Exposure of C. batrachus to CPF and MCP resulted in decreased activity of lactate dehydrogenase in the kidney, liver and muscle but its activity increased in the gills. The CPF caused inhibition of succinate dehydrogenase enzyme in all tissues. Induction in the activity of malate dehydrogenase was caused by both insecticides. Glycogen phosphorylase a was induced in all tissues, whereas glycogen phosphorylase ab showed both induction and inhibition. Of the two insecticides, CPF was more toxic and the recovery response was less. These results are important in the assessment of the risk caused by organophosphate insecticides on nontarget organisms, especially the food fish. PMID:21983276

Narra, Madhusudan Reddy; Begum, Ghousia; Rajender, Kodimyala; Rao, J Venkateswara

2011-10-07

318

Toxic impact of two organophosphate insecticides on biochemical parameters of a food fish and assessment of recovery response.  

UK PubMed Central (United Kingdom)

Sublethal effects of chlorpyrifos (CPF) and monocrotophos (MCP) on fish biochemical constituents were investigated along with the assessment of recovery response after cessation of intoxication. The fish, Clarias batrachus were exposed to 1.656 mg(-l) and 2.114 mg(-l) of CPF and MCP for 28 days. After 28 days, they were released in freshwater and allowed to recover for 21 days. The CPF exposure resulted in the decrease of carbohydrate and glycogen content, whereas MCP intoxication caused mixed response. Pyruvate and lactate contents were altered under the stress of CPF and MCP. Recovery of these alterations was observed after the cessation of toxicity. Exposure of C. batrachus to CPF and MCP resulted in decreased activity of lactate dehydrogenase in the kidney, liver and muscle but its activity increased in the gills. The CPF caused inhibition of succinate dehydrogenase enzyme in all tissues. Induction in the activity of malate dehydrogenase was caused by both insecticides. Glycogen phosphorylase a was induced in all tissues, whereas glycogen phosphorylase ab showed both induction and inhibition. Of the two insecticides, CPF was more toxic and the recovery response was less. These results are important in the assessment of the risk caused by organophosphate insecticides on nontarget organisms, especially the food fish.

Narra MR; Begum G; Rajender K; Rao JV

2012-05-01

319

Current and future prospects of commercial fish farming in Zambia  

Directory of Open Access Journals (Sweden)

Full Text Available According to the survey conducted, there were 15 land based commercial fish farms in Lusaka, Copperbelt and Northern provincesand 10 cage culture operators, mainly based on Lake Kariba. Fish production per hectare ranged between 13 and 18 tonnes while total productionwas estimated to be approximately 4971.37 metric tons. The weight of fish at harvest from ponds and tanks ranged from 250g to 350g per piecewhile under cage culture, where fish were regularly fed with floating pellets, ranged from 400 to 450g. Fish stocking density by most farmerswas 30,000 fingerlings per hectare and between 12,000 and 15,000 for cage culture. Those who operated fish hatcheries employed a technologythat manipulated genetic materials of Oreochromis andersonii and O. niloticus, resulting in production of all-male tilapia, simply referred to as“super males”. Environmental considerations remained a great challenge to the development of both land based commercial fish farms and cageculture on Lake Kariba. Higher fees were charged to do environmental impact assessment (EIA) studies before commencement of operation.

Confred G. Musuka; Felix F. Musonda

2012-01-01

320

Evolutionary Stable Stock Markets  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper shows that a stock market is evolutionary stable if andnonly if stocks are evaluated by expected relative dividends. Any othernmarket can be invaded by portfolio rules that will gain market wealthnand hence change the valuation. In the model the valuation of assetsnis given by the wealth ...

Evstigneev, Igor V; Hens, Thorsten; Schenk-Hoppé, Klaus Reiner

 
 
 
 
321

Stocks.com  

Science.gov (United States)

Stocks.com is a large metasite of investment resources from CyberFinancialNet, Inc. The searchable list spans topics of stocks and bonds, online investment services, and international government sites. Services on-site include a company data search engine and investment portfolio (registration required).

322

Coal stocks gain momentum  

Energy Technology Data Exchange (ETDEWEB)

Coal stock prices showed a healthy increase in the earnings period ending May 28 1993, according to COAL's Coal Mining Stock Index, compiled from 10 of the US coal industry's most dynamic stocks. The six month period studied in the index ran from Dec. 1, 1992 to May 28, 1993. The profile of coal stocks gained 75.38 points, or 3.48% from the last six-month term. Analysts say coal's outlook is improving, but stocks are still down from this time last year. Analysts agree that increased production and productivity coupled with an economic slowdown will be challenging for growth. In the future, coal businesses must restructure in order to remain competitive. 1 fig., 3 tabs.

Bloom, M.A.

1993-09-01

323

Assessment of carcinogenic potential of repeated fish fried oil in mice.  

Science.gov (United States)

Our prior studies have shown that single topical treatment of repeated fish fried oil extract (RFFE), containing various polycyclic aromatic hydrocarbons (PAHs), to the dorsal epidermis of mice caused enhancement of DNA damage along with higher expression of p53 and p21WAF1 proteins and cell-cycle arrest. In the present study carcinogenic potential of repeated fish fried oil (RFFO) and RFFE was assessed. Single topical application of RFFO (100 microL/animal) and RFFE (100-500 microg/animal) to Swiss albino female mice resulted in significant induction (1.8- to 7.4-fold) of ornithine decarboxylase activity. Twice weekly topical application of methylcholanthrene (MCA) for 24 wk or single topical application of 7,12-dimethylbenzanthracene (DMBA) or RFFO or RFFE, as initiator followed by twice weekly application of 12-O-tetradecanoyl phorbol myristate acetate (TPA) as promoter for 24 wk, resulted in development of skin papillomas after 6, 7, 18, and 9 wk, respectively. The cumulative number of tumors in MCA, DMBA/TPA, RFFE (200 microg)/TPA, and RFFE (500 microg)/TPA groups were 276, 168, 34, and 58 after 24 wk while negligible or minimal initiating activity was noticed in RFFO/TPA group. No tumors were found in animals either given twice weekly topical application of RFFO or a single initiating dose of DMBA followed by twice weekly application of RFFO. Histopathology of skin of animals treated with RFFE/TPA showed marked proliferation of epidermal layers along with abnormal mitosis and multinucleated tumor appearance. Skin of animals in groups RFFO/TPA and DMBA/RFFO showed sloughing and regeneration of epidermal layers, oedema along with proliferation of fibroblasts. Histochemical localization of gamma-glutamyl transpeptidase was found to be substantially higher in skin of mice treated with RFFO/TPA and RFFE/TPA. Animals treated with RFFO/TPA, DMBA/RFFO, and RFFE/TPA resulted in significant induction of cutaneous aryl hydrocarbon hydroxylase (AHH) (421-432%), ethoxyresorufin-O-deethylase (252-316%), and glutathione S-transferase (133-245%) activities. Animals treated with RFFO/TPA, DMBA/RFFO, and RFFE/TPA led to significant reduction in glutathione content (39-44%) with a concomitant increase in lipid peroxidation (254-492%). Animals treated with RFFO/TPA and RFFE/TPA led a significant decrease in catalase (43-69%) and superoxide dismutase (20-31%) activities while glutathione reductase activity was found to be diminished (23-51%) in RFFO, RFFO/TPA, DMBA/RFFO, and RFFE/TPA treated groups. These results suggest that RFFE possess skin tumor initiating activity and that it may have weak promoting activity as well, which may involve free radicals. PMID:16683249

Pandey, Manoj K; Das, Mukul

2006-10-01

324

Assessment of carcinogenic potential of repeated fish fried oil in mice.  

UK PubMed Central (United Kingdom)

Our prior studies have shown that single topical treatment of repeated fish fried oil extract (RFFE), containing various polycyclic aromatic hydrocarbons (PAHs), to the dorsal epidermis of mice caused enhancement of DNA damage along with higher expression of p53 and p21WAF1 proteins and cell-cycle arrest. In the present study carcinogenic potential of repeated fish fried oil (RFFO) and RFFE was assessed. Single topical application of RFFO (100 microL/animal) and RFFE (100-500 microg/animal) to Swiss albino female mice resulted in significant induction (1.8- to 7.4-fold) of ornithine decarboxylase activity. Twice weekly topical application of methylcholanthrene (MCA) for 24 wk or single topical application of 7,12-dimethylbenzanthracene (DMBA) or RFFO or RFFE, as initiator followed by twice weekly application of 12-O-tetradecanoyl phorbol myristate acetate (TPA) as promoter for 24 wk, resulted in development of skin papillomas after 6, 7, 18, and 9 wk, respectively. The cumulative number of tumors in MCA, DMBA/TPA, RFFE (200 microg)/TPA, and RFFE (500 microg)/TPA groups were 276, 168, 34, and 58 after 24 wk while negligible or minimal initiating activity was noticed in RFFO/TPA group. No tumors were found in animals either given twice weekly topical application of RFFO or a single initiating dose of DMBA followed by twice weekly application of RFFO. Histopathology of skin of animals treated with RFFE/TPA showed marked proliferation of epidermal layers along with abnormal mitosis and multinucleated tumor appearance. Skin of animals in groups RFFO/TPA and DMBA/RFFO showed sloughing and regeneration of epidermal layers, oedema along with proliferation of fibroblasts. Histochemical localization of gamma-glutamyl transpeptidase was found to be substantially higher in skin of mice treated with RFFO/TPA and RFFE/TPA. Animals treated with RFFO/TPA, DMBA/RFFO, and RFFE/TPA resulted in significant induction of cutaneous aryl hydrocarbon hydroxylase (AHH) (421-432%), ethoxyresorufin-O-deethylase (252-316%), and glutathione S-transferase (133-245%) activities. Animals treated with RFFO/TPA, DMBA/RFFO, and RFFE/TPA led to significant reduction in glutathione content (39-44%) with a concomitant increase in lipid peroxidation (254-492%). Animals treated with RFFO/TPA and RFFE/TPA led a significant decrease in catalase (43-69%) and superoxide dismutase (20-31%) activities while glutathione reductase activity was found to be diminished (23-51%) in RFFO, RFFO/TPA, DMBA/RFFO, and RFFE/TPA treated groups. These results suggest that RFFE possess skin tumor initiating activity and that it may have weak promoting activity as well, which may involve free radicals.

Pandey MK; Das M

2006-10-01

325

Assessment and exploitation of the pomfret fishery by the industrial fishing fleets in Bangladesh  

Directory of Open Access Journals (Sweden)

Full Text Available In this study, pomfret fishery data were collected from the 93 commercial fishing trawlers from July 2008 to June 2009 in Bangladesh. Total fish production of these fishing trawlers was 30191.071 MetricTons (MT). Among them, the estimated catch of pomfret was 305.466 MT of which caught within total 18651961.05 hours and an average catch per hour of pomfret was 0.016 kilogram (kg). Three species of pomfret were recorded under the family stromateidae and carangidae. The average tow duration of per trawler per day was 16.25 hours. The percentage contribution by weight showed that, the highest catchof percentage was 1.88 and the lowest was 0.38; and the average catch percentage of pomfret was 1.01 of the total fish production in the trawl fishing. The highest landing of pomfret was recorded 65.460 MTin the month of November, 2008 and lowest was 1.146 MT in July, 2008 at the same study period.

Roy Bikram Jit; Nripendra Kumar Singha; S.M. Hasan Ali; Gaziur Haman

2013-01-01

326

Mercury in fishes from Augusta Bay (southern Italy): risk assessment and health implication.  

Science.gov (United States)

Our study reports on the total mercury (HgT) concentrations measured in the muscles and livers of several benthic, demersal and pelagic fish species caught inside and outside of Augusta Bay (southern Italy), a semi-enclosed marine area, highly contaminated by the uncontrolled (since the 1950s to 1978s) discharge of the largest European petrochemical plant. Mercury levels in fish tissues are discussed with regard to specific habitat, size and/or age of the specimens and HgT distribution in the bottom sediments. Results suggest a still active Hg release mechanism from the polluted sediments to the marine environment. Also, the high HgT concentrations measured in fishes caught in the external area of the bay imply a potential role of Augusta Bay as a pollutant source for the Mediterranean ecosystem. Finally, values of hazard target quotient (THQ) and estimated weekly intake (EWI) demonstrate that consumption of fishes caught inside the bay represents a serious risk for human health. Also, data indicate that intake of fishes caught from the external area of the bay, especially for that concern demersal and benthic species, could be represent a significant component of risk for the local population. PMID:23485481

Bonsignore, M; Salvagio Manta, D; Oliveri, E; Sprovieri, M; Basilone, G; Bonanno, A; Falco, F; Traina, A; Mazzola, S

2013-02-24

327

Population structure and stock assessment of Hoplias malabaricus (Characiformes: Erythrinidae) caught by artisanal fishermen in river-reservoir transition area in Brazil  

Directory of Open Access Journals (Sweden)

Full Text Available Hoplias malabaricus is a viable economic alternative for artisanal fishermen who used to live on the banks of rivers that now are dammed in Brazil. In order to preserve the species’ natural stock, the main objectives of this study were to obtain bio-ecological information on this species reproduction, feeding dynamics and the description of the extent of its exploitation in river-reservoir transition area in Brazil. This way, from January to December 2005, different fishery catches were made with gill nets by artisanal fishermen, and a total of 426 individual H. malabaricus were obtained and sampled. From each specimen, the following biometric and biological data were analyzed: standard length, total weight, stomach contents, reproductive data such as sex, weight and gonadal maturation stage; with these data we estimated sex ratio, reproduction period and feeding habits. To assess growth parameters and infer on the degree of exploitation, the standard length frequency data were analysed using the FISAT (ELEFAN I) computer program. Data revealed a sex ratio of 0.8:1 (M:F), that reproduction occurs all year around, being more intense during spring and summer; it also showed that H. malabaricus is piscivorous. The growth parameters and mortality were estimated at: L?=35.18cm, k=0.32 year, longevity=9.3 years, Z=1.25 years, M=0.63 year and F=0.62 year. The weight-length relationship was: ln Wt=-3.1663+2.7456 ln Lp. The yield-per-recruit analysis produced the following values: E=0.496, Emax=0.916, E0.1=0.701 and E0.5=0.378. Overall, our data suggest that the stock of H. malabaricus is not yet overfished in the studied area. Rev. Biol. Trop. 59 (1): 71-83. Epub 2011 March 01.Hoplias malabaricus representa una alternativa económica viable para los pescadores artesanales que viven a la orilla de ríos que actualmente cuentan con represas en Brasil. El objeto del presente estudio fue evaluar la dinámica de la reproducción, alimentación, crecimiento y nivel de explotación de la especie nativa Hoplias malabaricus, capturada por pescadores artesanales en la zona de transición entre el río Paranapanema y el Embalse de Jurumirim. En 2005, los especimenes de H. malabaricus se obtuvieron utilizando redes agalleras de forma mensual y se registraron las siguientes características y datos biológicos de cada uno: longitud estándar, peso corporal, sexo, estadio reproductivo, peso de las gónadas y contenido estomacal. Estos datos fueron utilizados para estimar la proporción sexual, el período reproductivo y los hábitos alimenticios. Para evaluar los parámetros de crecimiento y el grado de explotación, los datos de frecuencia de la longitud estándar fueron analizados utilizando el software FISAT a través de la rutina ELEFAN I. Según los resultados obtenidos, la proporción sexual fue de 0.8:1 (macho:hembra); la reproducción fue observada durante todo el año, pero sobre todo en la primavera y el verano. El hábito alimentario fue piscívoro. Los parámetros de crecimiento y mortalidad fueron estimados en: L?=35.18cm, k=0.32/año; longevidad= 9.3, Z=1.25/año, M=0.63/año y F=0.62/año. La relación longitud-peso fue: Wt=-3.1663+2.7456lnLp. El análisis de rendimiento por recluta estimó los siguientes valores: E=0.496, Emax=0.916, E0.1=0.701 y E0.5=0.378. Puede concluirse que la población de H. malabaricus en la región estudiada todavía no está siendo altamente explotada.

José Luís Costa Novaes; Edmir Daniel Carvalho

2011-01-01

328

Stock Identification of Columbia River Chinook Salmon and Steelhead Trout, 1984-1985 Annual Report.  

Energy Technology Data Exchange (ETDEWEB)

Fish were collected from 60 stocks of chinook salmon and 62 stocks of steelhead trout. Electrophoretic analyses were completed on 43 stocks of chinook salmon and 41 stocks of steelhead trout and meristic counts were completed on 43 stocks of chinook and 41 stocks of steelhead. Statistical comparisons between year classes of our electrophoretic data indicate that most enzyme systems are stable over time but some may be dynamic and should be used with caution in our analyses. We also compared neighboring stocks of both spring chinook and steelhead trout. These comparisons were between stocks of the same race from adjacent stream systems and/or hatcheries. Differences in isozyme gene frequencies can be used to estimate genetic segregation between pairs of stocks. Analysis of the chinook data suggests that, as expected, the number of statistically significant differences in isozyme gene frequencies increases as the geographic distance between stocks increases. The results from comparisons between adjacent steelhead stocks were inconclusive and must await final analysis with more data. Cluster analyses using either isozyme gene frequencies or meristic characters both tended to group the chinook and steelhead stocks by geographic areas and by race and both methods resulted in generally similar grouping patterns. However, cluster analyses using isozyme gene frequencies produced more clusters than the analyses using meristic characters probably because of the greater number of electrophoretic characters compared to the number of meristic characters. Heterozygosity values for each stock were computed using the isozyme gene frequencies. The highest heterozygosity values for chinook were observed in summer chinook and the hatchery stocks while the lowest values were observed in the spring chinook and wild stocks. The results of comparisons of heterozygosity values among areas were inconclusive. The steelhead heterozygosity values were higher in the winter stocks than in the summer stocks and similar between hatchery and wild stocks. Heterozygosity values among the areas were very similar for the steelhead stocks. Analysis of variance tests indicate that significant differences exist among the stocks for scales in the lateral series, scale rows above the lateral line, anal rays, dorsal rays, vertebrae and paired fin rays for both steelhead and chinook. Tests on gill raker and branchiostegal counts will be conducted when those counts are completed. Morphometric characters were compared between fed and starved groups of steelhead trout to determine which characters may be affected by condition factor or fatness of the fish. The results show that the linear characters, some head measurements and the truss-type characters in the caudal peduncle are most likely to be unaffected by condition factor. The measurements in the gut area of the fish appear to be unsuitable for discriminating among the stocks since they are highly affected by condition factor.

Schreck, Carl B.; Sharpe, Cameron; Li, Hiram W. (Oregon State University, Oregon Cooperative Fishery Research Unit, Corvallis, OR)

1985-09-21

329

Mercury assessment and evaluation of its impact on fish in the Cecina river basin (Tuscany, Italy)  

International Nuclear Information System (INIS)

[en] This paper reports the results of mercury contamination monitoring in the Cecina river basin (Tuscany, Italy). Mercury was measured in the waters, sediments and fish species of the river and its most important tributaries. In fish specimens the organic form was also determined. The results showed high mercury levels in most of the samples analysed. Particularly high concentrations were found in the sediments of the S. Marta canal flowing into the Cecina, where a chlor-alkali plant discharges its wastes, and high levels were still detectable 31 km downstream from the confluence. Near the S. Marta confluence many fish specimens were very contaminated and a study on Leuciscus cephalus cabeda growth suggested that at this site mercury accumulation occurs in these organisms since they are very young. - Mercury entering water from a chlor-alkali plant near Tuscany has led to contamination of river food webs

2005-01-01

330

Use of fish farms to assess river contamination: Combining biomarker responses, active biomonitoring, and chemical analysis.  

Science.gov (United States)

Here we addressed the possible effects of trace levels of contaminants on fish by means of a combination of biomarker responses, active biomonitoring (ABM), and chemical analysis. In environmental studies, cytochromes P4501A (Cyp1A) and Cyp3A and related enzyme activities (7-ethoxyresorufin-O-deethylase, EROD, and benzyloxy-4-[trifluoromethyl]-coumarin-O-debenzyloxylase, BFCOD, respectively) are commonly used as biomarkers for evidencing exposure to a variety of contaminants. In a rainbow trout (Oncorhynchus mykiss) fish farm that is routinely sampled to obtain references regarding normal levels of such enzyme activities in freshwater fish, we observed a strong and punctual increase in these activities at the end of 2011. In order to shed light on the causes of this induction, we transferred some fish to a fish farm with controlled conditions and examined them using an active biomonitoring (ABM) approach. EROD activity showed a decrease of 80% from the original values after 7 days in the control farm, while BFCOD activity was also reduced after 15 days. Although not significant, a decrease in cyp1A and cyp3A mRNA levels was also observed. To determine the presence of pollutants, water and sediment samples from the river feeding the fish farm were analyzed by two-dimensional gas chromatography-time-of-flight mass spectrometry (GC×GC-TOF-MS). The screening study reflected a weak inflow of pollutants in the monitored area, which is located far from any industrial activity or densely populated cities. Trace levels of polyaromatic hydrocarbons (PAHs) and personal care products (the polycyclic musk fragrance HHCB, and triclosan) were detected in sediments, at concentrations ranging from 0.01 to 38ng/g dry weight, and in water from 4 to 441ng/L. The approach followed in this study proved useful as a biomonitoring technique for the early detection of trace contaminants. PMID:23928255

Quesada-García, Alba; Valdehita, Ana; Torrent, Fernando; Villarroel, Morris; Hernando, M Dolores; Navas, José M

2013-07-22

331

Assessing RET/PTC in thyroid nodule fine-needle aspirates: the FISH point of view.  

Science.gov (United States)

RET/PTC rearrangement and BRAF(V600E) mutation are the two prevalent molecular alterations associated with papillary thyroid carcinoma (PTC), and their identification is increasingly being used as an adjunct to cytology in diagnosing PTC. However, there are caveats associated with the use of the molecular approach in fine-needle aspiration (FNA), particularly for RET/PTC, that should be taken into consideration. It has been claimed that a clonal or sporadic presence of this abnormality in follicular cells can distinguish between malignant and benign nodules. Nevertheless, the most commonly used PCR-based techniques lack the capacity to quantify the number of abnormal cells. Because fluorescence in situ hybridization (FISH) is the most sensitive method for detecting gene rearrangement in a single cell, we compared results from FISH and conventional RT-PCR obtained in FNA of a large cohort of consecutive patients with suspicious nodules and investigated the feasibility of setting a FISH-FNA threshold capable of distinguishing non-clonal from clonal molecular events. For this purpose, a home brew break-apart probe, able to recognize the physical breakage of RET, was designed. While a ?3% FISH signal for broken RET was sufficient to distinguish nodules with abnormal follicular cells, only samples with a ?6.8% break-apart FISH signal also exhibited positive RT-PCR results. On histological analysis, all nodules meeting the ?6.8% threshold proved to be malignant. These data corroborate the power of FISH when compared with RT-PCR in quantifying the presence of RET/PTC in FNA and validate the RT-PCR efficiency in detecting clonal RET/PTC alterations. PMID:23722226

Caria, Paola; Dettori, Tinuccia; Frau, Daniela V; Borghero, Angela; Cappai, Antonello; Riola, Alessia; Lai, Maria L; Boi, Francesco; Calò, Piergiorgio; Nicolosi, Angelo; Mariotti, Stefano; Vanni, Roberta

2013-06-27

332

Assessment of Dissolved Oxygen Mitigation at Hydropower Dams Using an Integrated Hydrodynamic/Water Quality/Fish Growth Model  

Energy Technology Data Exchange (ETDEWEB)

Dissolved oxygen (DO) in rivers is a common environmental problem associated with hydropower projects. Approximately 40% of all FERC-licensed projects have requirements to monitor and/or mitigate downstream DO conditions. Most forms of mitigation for increasing DO in dam tailwaters are fairly expensive. One area of research of the Department of Energy's Hydropower Program is the development of advanced turbines that improve downstream water quality and have other environmental benefits. There is great interest in being able to predict the benefits of these modifications prior to committing to the cost of new equipment. In the case of turbine replacement or modification, there is a need for methods that allow us to accurately extrapolate the benefits derived from one or two turbines with better design to the replacement or modification of all turbines at a site. The main objective of our study was to demonstrate a modeling approach that integrates the effects of flow and water quality dynamics with fish bioenergetics to predict DO mitigation effectiveness over long river segments downstream of hydropower dams. We were particularly interested in demonstrating the incremental value of including a fish growth model as a measure of biological response. The models applied are a suite of tools (RMS4 modeling system) originally developed by the Tennessee Valley Authority for simulating hydrodynamics (ADYN model), water quality (RQUAL model), and fish growth (FISH model) as influenced by DO, temperature, and available food base. We parameterized a model for a 26-mile reach of the Caney Fork River (Tennessee) below Center Hill Dam to assess how improvements in DO at the dam discharge would affect water quality and fish growth throughout the river. We simulated different types of mitigation (i.e., at the turbine and in the reservoir forebay) and different levels of improvement. The model application successfully demonstrates how a modeling approach like this one can be used to assess whether a prescribed mitigation is likely to meet intended objectives from both a water quality and a biological resource perspective. These techniques can be used to assess the tradeoffs between hydropower operations, power generation, and environmental quality.

Bevelhimer, Mark S [ORNL; Coutant, Charles C [ORNL

2006-07-01

333

Pond Fish Culture Practices in Nigeria  

Directory of Open Access Journals (Sweden)

Full Text Available Pond fish culture practices in Nigeria was reviewed to refresh the minds of fish and other interested stake holders on some basic principles involved in pond fish culture. Fish pond system is the commonest agricultural techniques in the Niger Delta Region of Nigeria. Profit making, job creation, provision of raw materials for several industries and increase in foreign exchange earnings are some benefits. However, loss of land and introduction some water borne diseases are some disadvantages in pond fish culture. This articles reviews the fish pond management processes, stocking of ponds, feeding of fish, types of culture, fish farming combined with other branches of agriculture, rearing of fish for purposes other than food, other fish culture, types of fish used for fish culture in central east Africa, general biology of the species of value in fish culture and suitable combinations of fish for stocking to reawaken the minds of individuals, companies and government on the need to develop pond fish culture in Nigeria.

J.A. Akankali; J.F.N. Abowei; A. Eli

2011-01-01

334

Quality Index Method (QIM) to assess the freshness and shelf life of fish  

Scientific Electronic Library Online (English)

Full Text Available Abstract in english The aim of this work was to develop a sensory method as the objective measure of quality of the fishes at all the key stages of fishery chain, from catch to consumer. The Quality Index Method (QIM) is based on a structured scaling for quality measurements and provides accurate and precise information concerning the freshness and a prediction of the remaining shelf-life for specie-specific fishes. The method is discussed and some future outlooks and need are pointed in ord (more) er to stimulate the implementation of QIM in the relevant parts of the fishery chain giving unique information of the quality.

Bernardi, Daniella Cristina; Mársico, Eliane Teixeira; Freitas, Mônica Queiroz de

2013-08-01

335

Fish Loss in Austrian Fish-Ponds as a Result Of Otter (Lutra lutra L.) Predation  

Directory of Open Access Journals (Sweden)

Full Text Available This paper summarises work on the relationship between otters and fish farmers in a country where there is a compensation scheme for fish losses attributed to otters. The results show that otters are no threat to fish farming. Otters do forage in fish ponds and some fish are damaged/eaten, but there is more use of large ponds than small ones. Otter predation can cause secondary damage to carp stocks. "Missing" fish are often attributed to otters when no other cause can be found. In the cold winter months when many water bodies are frozen over, fish ponds cdan be an essential food source for otters.

Michaela Bodner

1995-01-01

336

Fish can get diseases too  

Science.gov (United States)

Infectious diseases are increasingly recognized as an important component of the ecology of fish in the wild. Many of the viral, bacterial, protozoan and fungal pathogens of fish that were initially discovered in captive fish have their origin among wild populations; however, the impact of disease among these free-ranging stocks has been difficult to study. At the WFRC, combinations of field and laboratory investigations, aided by the tools of molecular biology, have begun to provide information on the ecology of infectious diseases among natural populations of fish in both freshwater and marine ecosystems.

Thorsteinson, Lyman

2005-01-01

337

Preliminary yield per recruit analysis of the Indian Ocean yellowfin and bigeye fisheries The stock assessment of tunas in the Indian Ocean  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Ce document présente des estimations de F par âge et par engin sur l'albacore et le patudo par les diverses pêcheries thonières de l'Océan Indien et tente d'analyser l'interaction théorique, en termes de production par recrue, entreengins de surface et palangre sur le stock d'albacore au moyen de si...

Marsac, Francis

338

Assessment of heavy metal concentrations in water, sediment and biota (fish and crabs) samples from the Densu Delta  

International Nuclear Information System (INIS)

The aim of the study was assess the concentration of some selected heavy metals in water, sediments and biota (fish and crab) sampled from the Densu Delta. In situ and laboratory based analysis were carried out to measure the following physicochemical properties of surface water from the delta; temperature, pH, electrical conductivity (EC), salinity, total dissolved solids (TDS), alkalinity, sodium ion concentration (Na+), potassium ion concentration (K+), chloride ion concentration (Cl), bicarbonate concentration, phosphate concentration, nitrate concentration, sulphate concentration and biochemical oxygen demand (BOD). Heavy metal (Fe, Zn, Cu, Ni, Cd, Cr, Pb and Hg) concentrations in water, sediments, fish and crab sampled at six sites from the Densu Delta wetland in the month of December, 2009 were analysed using VARIAN Fast Sequential Atomic Absorption Spectrophotometer (AAS) model AA240 FS. Two fish species; Blackchin tilapia (Sarotherodon melanotheron), White mullet (Mugil curema) and one species of crab; Blue swimming crab (Callinectes amnicola) were collected from the Densu Delta wetland and analysed. Heavy metal contents in the fish were higher in gill tissue than muscle tissue while in crabs concentrations were higher in the soft tissue than the shell. Levels of Fe, Zn and Cu in the muscle tissue of S. melanotheron were greater than the levels detected in the muscle tissue of M. curema. Cd, Ni and Hg were detected in gill tissue but not in the muscle tissue of S. melanotheron, M. curema on the other hand contained these metals in both gill and muscle tissue. The maximum level of Fe (34.98 mg/L), Zn (25.08 mg/L) in the muscle of S. melanotheron was observed at Bortianor and Zn (2.70 mg/L) was observed at Tetegu. In the M. curema, the maximum level of Fe (34.66 mg/L), Zn (15.9 mg/L) and Cu (1.43 mg/L) was detected at Aplaku, Tetegu and Faana respectively. Heavy metal concentrations were higher in sediment than water. The presence of elevated levels of Cd and Ni in the muscle tissue of the white mullet fish from Tetegu and Faana, is a potential public health hazard to the inhabitants of these two communities and other neighbouring communities who depend on fish from the delta as their source of protein. (au)

2010-01-01

339

ALK-Rearranged Lung Cancer in Chinese: A Comprehensive Assessment of Clinicopathology, IHC, FISH and RT-PCR.  

UK PubMed Central (United Kingdom)

Approximately 3-7% of non-small cell lung cancers harbor an anaplastic lymphoma kinase (ALK) gene fusion, constituting a new molecular subtype of lung cancer that responds to crizotinib, an ALK inhibitor. Although previous studies have evaluated ALK-rearranged lung cancers, the comprehensive analysis of lung cancer in Chinese has not well assessed. Herein, we identified 44 cases of ALK-rearranged samples by fluorescent in-situ hybridization (FISH), immunohistochemistry (IHC), and reverse transcription polymerase chain reaction (RT-PCR) in a large number of surgically resected lung cancers. All 44 ALK-rearranged lung cancers were adenocarcinomas, with 2 cases having additional focal squamous components. The goal was to analyse the clinicopathological features of ALK-rearranged lung adenocarcinomas. Our data showed that a cribriform structure, prominent extracellular mucus and any type of mucous cell pattern may be either sensitive or specific to predict an ALK rearrangement. We used FISH as the standard detection method. We compared the ALK rearrangement accuracy of FISH, RT-PCR and IHC. RT-PCR could define both the ALK fusion partner and the fusion variant, but seemed unable to detect all translocations involving the ALK gene. It is noteworthy that IHC using the D5F3 antibody (Cell Signaling Technology) showed higher sensitivity and specificity than the ALK1 antibody (Dako). Therefore, we conclude that IHC remains a cost-effective and efficient technique for diagnosing ALK rearrangements and that D5F3 can be the optimal screening antibody in clinical practice.

Li Y; Pan Y; Wang R; Sun Y; Hu H; Shen X; Lu Y; Shen L; Zhu X; Chen H

2013-01-01

340

Assessment of toxic effects of triclosan on the swordtail fish (Xiphophorus helleri) by a multi-biomarker approach.  

UK PubMed Central (United Kingdom)

The toxic effects of triclosan (TCS) on the swordtail fish (Xiphophorus helleri) were assessed based on various biomarkers including enzymatic activities of ethoxyresorufin O-deethylase (EROD), erythromycin N-demethylase (ERND) and glutathione-s-transferase (GST) and mRNA expression levels of CYP1A, CYP3A, glutathione S-transferase (GST) and P-glycoprotein (P-gp). The acute toxicity test showed the LC(50) value of 1.47 mg L(-1) for TCS. The mRNA expressions of CYP1A, CYP3A, GST and P-gp showed dose-effect relationships in female swordtail fish when exposed to TCS, These mRNA expression levels were found more sensitive to TCS exposure than the enzymatic activities of EROD, ERND and GST do. In addition, the male fish displayed higher gene expression levels and more dramatic changes in enzyme activities than the females did. Our data further demonstrated that TCS was a typical inducer to Phase I and Phase II metabolism enzymes and genes, suggesting it is a potential ecotoxicological risk to aquatic ecosystems.

Liang X; Nie X; Ying G; An T; Li K

2013-01-01