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The spawning grounds of the chub mackerel (Scomber japonicus) and spotted mackerel (Scomber australasicus) in the East China Sea were estimated based on catch statistics of the Japanese large- and medium-type purse seine fishery from 1992 to 2006. Biometric data were obtained from specimens caught by purse seiners in the East China Sea from 1998 to 2006. Gonadosomatic index (GSI) at 50% sexual maturity of chub mackerel and spotted mackerel females was 2.5 and 2.6, respectively. Using this criterion for GSI, chub mackerel larger than 275 mm and spotted mackerel larger than 310 mm in fork length were considered to be mature. Mature chub mackerel was observed in the area of 15-22degC sea surface temperature (SST), and mature spotted mackerel was observed in the area of 17-25degC SST. The spawning period of chub mackerel ranged from February to June, and that of spotted mackerel ranged from February to May in the East China Sea. The spawning grounds were estimated from the distributions of catch per unit effort (CPUE) of spawners and SST. As a result, the spawning ground of chub mackerel was estimated to be in the central and southern part of the East China Sea and the area west of Kyushu in February, March, and April, and in the central part of the East China Sea, the area west of Kyushu and Tsushima Straight in May, and in Tsushima Straight and western part of the Sea of Japan in June. The spawning ground of spotted mackerel was estimated to be in the central and southern part of the East China Sea and southern coastal area of Kyushu in February, March, and April, and the central and southern part of the East China Sea and the area west of Kyushu in May.

:  Univariate and multivariate autoregressive integrated moving average (ARIMA) models were used to model and forecast the monthly pelagic production of fish species in the Mediterranean Sea during 1990–2005. Autocorrelation (AC) and partial autocorrelation (PAC) functions were estimated, which led to the identification and construction of seasonal ARIMA models, suitable in explaining the time series and forecasting the future catch per unit of effort (CPUE) values. Univariate and multivariate ARIMA models satisfactorily predicted the total pelagic fish production and the production of anchovy, sardine, and horse mackerel. The univariate ARIMA models demonstrated a good performance in terms of explained variability and predicting power. The current findings revealed a strong autoregressive character providing relatively high R2 and satisfactory forecasts that were close to the recorded CPUE values. The present results also indicated that the multivariate ARIMA outperformed the univariate ARIMA models in terms of fitting accuracy. The opposite was evidenced when testing the forecasting accuracy of the two methods, where the univariate ARIMA models overall performed better than the multivariate models. The observed seasonal pattern in the monthly production series was attributed to the intrinsic nature of the pelagic fishery. As anchovy, sardine, and horse mackerel represent main target species in the Mediterranean pelagic fishery, the findings of the present study provided direct support for the potential use of accurate forecasts in decision making and fisheries management in the Mediterranean Sea.

The total content of fat soluble vitamins and their percentages in the recommended daily intake for humans per 100 g portion, fatty acids composition, the atherogenic (IA) and thrombogenicity (IT) indices in two freshwater fish species - Common carp (Cyprinus carpio) and European catfish (Sillurus glanis) were investigated. Retinol contents in fresh edible tissues of the Common carp and European catfish were found to be 30.8 +/- 3.4 mg/100 g wet weight (ww) for the Common carp 30.8 +/- 3.4 microg/100 g ww and 1.9 +/- 0.1 microg/100 g ww for the European catfish, cholecalciferol contents 14.8 +/- 1.0 and 3.1 +/- 0.1 microg/100 g ww, and alpha-tocopherol contents 2764.5 +/- 44.0 and 2182.5 +/- 31.5 microg/100 g ww, resp. The sum of monounsaturated FA accounted for 50.02% (catfish) and 23.15% (carp). Polyunsaturated FA (PUFA) showed a higher level in the carp (36.75%) and a lower one in the catfish (21.64%). Both fishes are good sources of cholecalciferol in terms of the recommended daily intake of vitamins established in Bulgaria. Three fat soluble vitamins, n-3 PUFAs content, and IA value were higher in carp. IT values were similar for both species.

The monthly and geographical abundances and size compositions of Pacific saury were compared between the high-seas and coastal fishing grounds in the northwestern Pacific during 2000-2005 based on Taiwanese fishery data. The large-sized saury was dominant (44.3-71.4% of the catch) in the beginning of the fishing season, while the medium-sized saury followed and dominated from September to the end of the fishing season (70.1-92.4% of the catch). In the high seas, the total catch per unit effort (CPUE) (about 71.2% of the mean coastal value) and both the large- (about 55.0%) and medium-sized saury CPUEs (about 81.8%) were significantly smaller than those in the coastal waters. The mean proportions of the large- and medium-sized saury in the high-seas catch were about 86.6 and 107.0% of the coastal values, respectively. CPUEs for the total catch and the catch of medium-sized saury varied in a highly consistent way. The total and medium-sized CPUEs were negatively correlated with the sea-water temperature. When the temperature was held the same statistically, the total and medium-sized CPUEs were larger in the shoreward, southward, and shallower waters of the fishing grounds, while the large-sized CPUE was larger in the shoreward waters.

The catch per unit effort (CPUE) is a widely used index for assessing the abundance of exploited populations in fishery management. To obtain appropriate CPUE values, it is essential to standardize catch-effort data from fisheries. This task is particularly important for squid fisheries because squid generally have a short life-span and are vulnerable to environmental variability, and thus effective fishery management should take such factors into account. In this study, we analyzed unit catches of paired vessels operating under similar fishing conditions to calculate their relative fishing power (RFP) in order to standardize the CPUE of the Taiwanese fleet jigging for Illex argentinus in the Southwest Atlantic. To evaluate the appropriateness of the method, we used a logbook dataset covering eleven years (1993-2003), in which 93.5% of the total catch during the period was included. The results indicate that 98.7% of the fishing effort can be standardized according to the estimated RFP. Compared to nominal CPUE, the standardized CPUE values projected an explainable temporal pattern, indicating an increasing trend in abundance from 1995 to 1999 and a subsequent sharp plunge from 1999 to 2003. However, the RFP was not related to apparent physical factors of the vessel, such as gross tonnage or vessel length. Our evaluations suggest that the RFP method is appropriate for standardizing the CPUE, so that it can serve as an abundance index that reflects the annual recruitment size of the squid fishery, because the quality of the method can potentially take possible affecting factors into account in order to satisfy the general assumptions of standardization criteria. However, the effects of varying the settings of parameters should be carefully examined prior to applying this standardization method to other squid fisheries.

The effect of water temperature and flow on the migration of fish was observed using weekly inspections of a fishpass on the lowland section of the River Elbe (Střekov, Czech Republic) from spring to fall 2003 and 2004. The effect was examined separately for immature (up to 2 years old) and adult fish and also the most abundant species (roach Rutilus rutilus, bleak Alburnus alburnus, chub Squalius cephalus, gudgeon Gobio gobio). More than 13 thousand fish from 23 species were recorded in the fishpass during both years. The highest levels of fish occurrence in the fishpass were observed during the spring spawning migrations of adults (April–May) as well as during the late summer and fall migrations of adult and immature fish (September–November). While the total number of both fish age categories was significantly related to the interaction of water temperature and flow, however, responses of individual species and age categories differed from each other. The numbers of adult bleak, chub and gudgeon increased with higher temperature. The maximum numbers of adult bleak migrated at medium values of temperature (15–20 °C) and flow (140–270 m3 s-1). The abundances of adult chub and adult plus immature gudgeon were higher with higher flow. The numbers of immature bleak and chub decreased with increasing flow. The numbers of adult and immature roach were influenced only by water flow with maximal numbers migrating under medium values of flow. Generally, we observed that immature fish and small- and middle-sized species required lower values of water flow than adult fish or large species to facilitate their movement. The exception was gudgeon, which required higher values of flow for its migration, a feature that could be related to its bottom dwelling nature or rheophily.

After growing steadily, particularly in the last four decades, aquaculture is for the first time set to contribute half of the fish consumed by the human population worldwide. This reflects not only the vitality of the aquaculture sector but also global economic growth and continuing developments in fish processing and trade. Until a year or so ago, production trends in aquaculture and capture fisheries were continuing without any drastic modifications - with the capture fisheries sector regularly producing between 90 and 95 million tonnes per year, and aquaculture production growing rapidly, albeit at a gradually slowing pace. This issue of The State of World Fisheries and Aquaculture features some aspects of fisheries and aquaculture that may receive increasing attention. These include climate change, the use of marine genetic resources in areas beyond national jurisdiction, and the proliferation of private standards and certification schemes in the international fish trade. This report also highlights some of FAO's special studies. Among these are the use of wild-fishery resources as seed and feed in aquaculture, and reviews of the world's shrimp fisheries and of the management of marine capture fisheries in the Pacific Ocean.

:  The recruitment abundance index of Pacific bluefin tuna Thunnus orientalis was estimated from 1980 to 2003 fishing year by using the troll fishery data in Nagasaki Prefecture, western Japan. It has been shown that the troll fishery in Nagasaki Prefecture operates with good time–area coverage of the species habitat, and that the fishing power slightly changed during the period analyzed, based on fisheries statistics, published information, and interviews with the fishers. Average catch per unit effort (CPUEs) were standardized by a generalized linear model (GLM) considering the effects of fishing year, season and landing area. Standardized CPUE of age‐0 bluefin tuna showed larger fluctuations year by year than the nominal CPUE combined for all ages. High CPUEs in fishing years of 1981, 1994, 1996 and 1999 were observed. Data from these years agreed with the higher recruitments estimated by virtual population analysis (VPA) or higher catch of age‐0 fish reported for the Pacific side. The age‐specific standardized CPUE of age‐0 bluefin tuna in this study was judged to be a useful indicator of recruitment.

Biological parameters, length-frequency distributions and catches of king soldier bream, Argyrops spinifer, in Oman according to fleet (gear/technique) and region was compiled by monthly sampling in 2001 to 2002. Length cohort and yield per recruit analyses were examined. The results showed that: the status of the stock is healthy, the average fishing mortality rate is moderate (0.1) and acts in general on the adult fraction of the stock; An increase in total fishing effort would not lead to any long-term substantial increase of the catch (according the uncertainty of M value); however, the spawning stock biomass would decrease significantly; A moderate (about 20 percentage) modification of minimum length limit in catches would not affect, substantially, the sustainable yield and the spawning stock biomass; Any regulation of trawler fishing by closed season (i.e. restricted trawler activities during some seasons) would not have a significant effect on the long-term yield

A procedure is suggested for estimation of the approximate confidence intervals of the extracted catch per unit effort (CPUE) year trend in the delta-type two-step model used for CPUE standardization with a lot of zero-catch data. This method is a simple way to combine the Taylor expansion and delta method and is suitable for practical use. This model was applied to the catch and effort data with more than 80% zero catch for silky shark in the North Pacific Ocean caught by Japanese training vessels. As a result, realistic values of the 95% confidence interval of CPUE year trend are obtained. A method for left-right ynsymmetrical interval estimation based on the asymptotic normality of the natural logarithm of CPUE is also suggested. In the example of silky shark, both CPUE year trends obtained from these two methods are similar.