Sardinella Zunasi Research Articles

Effect of fermentation on antioxidant, antimicrobial, anti-inflammatory, and anti-Helicobacter pylori adhesion activity of Ulmus davidiana var. japonica root bark.

The limited yield of Ulmus davidiana var. japonica root bark (URB) extract is considered an economic loss to the food industry. Improving extraction yield and bioactivity through fermentation increase the industrial usage of URB. The study aims to optimize the fermentation with cellulolytic and pectinolytic bacteria and evaluate the bioactivity and anti-Helicobacter pylori activity of the fermented URB extract. URB fermentation with the Bacillus licheniformis FLa3, isolated from salted seafood (Sardinella zunasi), under optimal conditions (37°C, pH 6, 10% inoculum dose, and 36h) improved the extraction yield by 36% compared to the control. The antioxidant and antimicrobial activity of the fermented extract were significantly higher than non-fermented extract. High-performance liquid chromatography results confirmed that the fermentation increased the proportion of bioactive components such as catechin (171.7%), epicatechin (144.3%), quercetin (27.3%), and kaempferol (16.7%). The results confirmed that the fermentation increased both the extraction yield and bioactivity.

Nutritional contribution of terrestrial organic carbon to four fish species in the Yellow River Estuary and adjacent coastal waters

Only a small amount of terrestrial organic carbon was found in the ocean organic carbon pool, though 0.40 Gt terrestrial organic carbon was transported to ocean via estuaries each year. This finding indicated that large quantity of terrestrial organic carbon was depleted in the estuaries and coasts, which provided additional materials and energy for the ecosystem. To investigate the material and energy supplement of terrestrial organic carbon transported by the Yellow River to the estuary and coastal system, the nutritional contribution of terrestrial organic carbon to four fish species: <italic>Acanthogobius ommaturus</italic>, <italic>Cynoglossus joyneri</italic>, <italic>Chaeturichthys stigmatias</italic>, <italic>Sardinella zunasi</italic>, was studied using multivariate analysis of similarity (MANOSIM) and stable isotope analysis in R (SIAR). In MANOSIM, the similarity carbon and nitrogen stable isotope in the temporal level was studied by the factors of species and seasons, and that in the spatial level was studied by the factors of species and stations. The similarity was judged by <italic>R</italic>. <italic>R</italic><0.25, similarity was high. 0.25≤<italic>R</italic>≤0.50, similarity was in the middle level. <italic>R</italic>>0.50, similarity was in the low level. In the study of SIAR, the nutritional sources of four fish species were considered as riverine, terrestrial and marine sources. The carbon stable isotope of riverine, terrestrial and marine source was (-30.0±0.4) ‰, (-26.0±0.4) ‰, and (-18.1±0.9) ‰ respectively. And the nitrogen stable isotope of riverine, terrestrial and marine source was (9.0±0.7) ‰, (1.0±0.7) ‰, and (6.0±1.2) ‰ respectively. Trophic enrichment factors (TEF) of carbon and nitrogen stable isotope was (1.1±1.3) ‰ and (2.8±1.4) ‰ respectively. We found that carbon and nitrogen stable isotope of four species showed no significant difference either in temporal level (<italic>R</italic>=0.08, <italic>P</italic><0.01) or in spatial level (<italic>R</italic>=0.19, <italic>P</italic><0.01) by MANOSIM. However, temporal and spatial variations of nutritional contribution of terrestrial organic carbon to four species were obvious. The nutritional contribution of terrestrial organic carbon was 8.7%, 7.3%, 4.3% and 32.0% higher in summer than that in autumn for <italic>Acanthogobius ommaturus</italic>, <italic>Cynoglossus joyneri</italic>, <italic>Chaeturichthys stigmatias</italic> and <italic>Sardinella zunasi</italic> respectively. And nutritional contribution of terrestrial organic carbon was 19.8%, 12.4%, 14.1% and 13.2% higher in estuary than that in coast for <italic>Acanthogobius ommaturus</italic>, <italic>Cynoglossus joyneri</italic>, <italic>Chaeturichthys stigmatias</italic> and <italic>Sardinella zunasi</italic> respectively. Temporal and spatial variations of Yellow River transporting terrestrial organic carbon may lead to variations.

Comparative otolith morphology and species identification of clupeids from Japan

The amount of interspecific and ontogenetic variation in otolith shape among clupeid fishes from Japan was investigated to create a key to identify otoliths of these species found in the stomach contents of piscivorous predators, fossiliferous beds, and archaeological sites. The interspecific comparison with 12 species (Clupea pallasii, Etrumeus micropus, Herklotsichthys quadrimaculatus, Ilisha elongata, Konosirus punctatus, Nematalosa come, Nematalosa japonica, Sardinella aurita, Sardinella melanura, Sardinella zunasi, Sardinops melanostictus, and Spratelloides gracilis) revealed morphological variation in otolith shape, OL:OH and AL:RL ratios, rostrum, marginal structures, and features of the crista superior. Intraspecific changes were analyzed in two species (E. micropus and S. melanostictus), revealing ontogenetic changes in OL:OH ratio and consequently otolith shape as well as changes in marginal features. Overall, this study shows that the key morphological features can be used as diagnostic features for identification of clupeid otoliths.

Nutritional characteristics of marine fish Sardinella zunasi Bleeker and immunostimulatory activities of its glycoprotein.

Sardinella zunasi Bleeker, an edible and medicinal marine fish, is largely distributed in tropical oceans. However, the chemical composition and nutritional properties of this species have not yet been investigated. In the present study, proximate composition, fatty acids, amino acids, taurine, and minerals of S. zunasi Bleeker were characterized, and the immunostimulatory properties of its glycoprotein were evaluated. The results indicated the presence of crude protein (19.66%), crude lipid (6.29%) and carbohydrate (0.74%) in S. zunasi Bleeker; monounsaturated fatty acids and polyunsaturated fatty acids in the fatty acid composition of S. zunasi Bleeker were 25.00% and 31.01%, respectively; S. zunasi Bleeker was rich in taurine (219 mg/100 g) and essential amino acids (5.57 g/100 g). In addition, the glycoprotein of S. zunasi consisted of protein and sugars, with a total content of 34.25% and 16.27%, respectively. The glycoprotein showed significant effects on promoting NO, TNF-α and IL-6 in a dose-dependent manner in RAW264.7 macrophage cells. Thus, these findings provide a scientific basis for the further utilization of glycoprotein from S. zunasi Bleeker.

莱州湾鱼类群落优势种生态位

PDF HTML阅读 XML下载 导出引用 引用提醒 莱州湾鱼类群落优势种生态位 DOI: 10.5846/stxb201408281711 作者: 作者单位: 山东省海洋资源与环境研究院,山东省海洋资源与环境研究院,山东省海洋资源与环境研究院,烟台市水产研究所 作者简介: 通讯作者: 中图分类号: S931.1 基金项目: 山东省渔业资源增殖效果评价（SD-XGPJ-2012-2）；山东省优秀中青年科学家科研奖励基金（BS2012HZ030） Ecological niche of dominant species of fish assemblages in Laizhou Bay, China Author: Affiliation: Shandong Marine Resource and Environment Research Institute,Shandong Provincial Key Laboratory of Restoration for Marine Ecology,Shandong Marine Resource and Environment Research Institute,Shandong Provincial Key Laboratory of Restoration for Marine Ecology,Shandong Marine Resource and Environment Research Institute,Shandong Provincial Key Laboratory of Restoration for Marine Ecology,Yantai Fisheries Research Institute Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:根据2011年5月、8月、10月和12月莱州湾底拖网调查资料，对该海域鱼类群落优势种的生态位进行了研究。结果表明，全年调查共捕获鱼类49种，各季节优势种种类数分别为春季3种，夏季5种，秋季3种，冬季4种。夏、冬季优势种的丛生指数较低，春、秋季较高；冬、春季优势种的平均拥挤度较低，夏、秋季较高。基于欧氏距离的优势种丰度聚类结果同优势度排序结果吻合。主成分分析（PCA）表明，青鳞小沙丁鱼（Sardinella zunasi）和赤鼻棱鳀（Thryssa kammalensis）分别是影响第一轴和第二轴的主要种类。绯鱼衔（Callionymus beniteguri）、鲬（Platycephalus indicus）、髭缟虾虎鱼（Tridentiger barbatus）和短吻红舌鳎（Cynoglossus joyneri）是时空二维生态位宽度最高的种类（>2）。时空生态位显著重叠（>0.6）的种类有7组，其中银姑鱼（Pennahia argentata）和皮氏叫姑鱼（Johnius belengerii）重叠值最高（0.798）。δ13C值变幅（CR）最大的种类为斑鱼祭（Konosirus punctatus），δ15N值变幅（NR）最大的种类为青鳞小沙丁鱼；青鳞小沙丁鱼和鱼祭生态位总面积超过20，皮氏叫姑鱼生态位总面积最小（1.38）且与其他优势种营养生态位重叠较高。等级聚类、排序、PCA和优势种排序结果较一致，而与时空生态位宽度分析结果差异较大，表明莱州湾鱼类群落结构受洄游鱼类的影响较大。时空生态位宽度较高的种类主要为集群特征不明显的周年定居种（绯鱼衔、鲬、短吻红舌鳎等底层鱼类），而季节洄游种（青鳞小沙丁鱼、鱼祭、赤鼻棱鳀等中上层鱼类）因时间生态位宽度较低导致时空生态位宽度较低。时空生态位和营养生态位分析表明，生态位重叠导致的资源利用性竞争并不是导致莱州湾鱼类群落结构现状的决定性因素，而更多可能是人为干扰形成的。 Abstract:Laizhou Bay, an estuary of the Yellow River, is one of the three most important bays of the Bohai Sea, China. It is characterized by a high level of primary productivity and is one of the most important spawning and feeding grounds for most fish species in the Yellow Sea and Bohai Sea. After decades of overfishing, the dominant species of the fish assemblage have been altered. Ecological niche describes how an organism or population responds to the distribution of resources. Therefore, studies on ecological niches are extremely important to clarify the ecological dynamics of different species and the mechanism of interspecific coexistence and competition, as they are a fundamental tool for the conservation and assessment of fish stocks, as well as for the analysis of the ecosystem as a whole. Data were obtained from a bottom trawl survey conducted in Laizhou Bay (119°05'-120°00'E, 37°12'-37°40'N) in 2011. The most dominant species that contributed to 97.2% of biomass and 98.4% of abundance were used for the hierarchical cluster analysis, non-metric multidimensional scaling (NMDS), principal component analysis (PCA), and spatio-temporal niche analysis. Tissue samples were collected from the 12 most dominant species recorded in the trawl-survey catches. δ13C and δ15N stable-isotope analyses were performed to assess the trophic niche. A total of 49 fishes were collected. The assemblage density of dominant species was low in the summer and winter and high in the spring and autumn. The mean crowding of the dominant species was low in the spring and winter, and high in the summer and autumn. The results of the hierarchical cluster analysis based on the Euclidean distance showed a similarity with the results of the ecological dominance analysis. The PCA showed that Sardinella zunasi was one of the species that mostly affected the first axis, and Thryssa kammalensis mostly affected the second axis. Callionymus beniteguri had the highest value of tempo-spatial niche width, followed by Platycephalus indicus, Tridentiger barbatus, and Cynoglossus joyneri. Significant overlap of spatio-temporal niche occurred between the seven groups:Pennahia argentata vs. Setipinna taty (0.798), S. taty vs. Johnius belangerii (0.793), C. joyneri vs. J. belangerii (0.771), Chaeturichthys stigmatias vs. J. belangerii (0.770), Konosirus punctatus vs. Scomberomorus niphonius (0.763), and K. punctatus vs. C. joyneri (0.625). Konosirus punctatus had the highest δ13C range (CR=9.2), and J. belangerii had the highest δ15N range (NR=7.1). The total area (TA) of the trophic niche of S. zunasi and K. punctatus were the highest, both being larger than 20. Johnius belangerii had the lowest TA (1.38); however, it had a significant overlap with other species, such as C. stigmatias, C. joyneri, and P. argentata. The results showed a similar trend with cluster analysis, NMDS, and PCA; however, the trend was different with the tempo-spatial niche analysis. The non-migration species, which lives throughout year in the bay, with lower assemblage densities had a higher value of spatio-temporal niche width. The seasonal migratory species had a lower tempo-spatial niche width because of the low temporal niche width. The high spatio-temporal niche overlap between the most dominant species found in this study also reflected a high degree of homogeneity of fish assemblies in the Laizhou Bay. Competition owing to niche overlap was not the decisive factor that formed the community structure of nekton in the Laizhou Bay. The community structures might be most affected by anthropogenic activities. 参考文献 相似文献 引证文献

Length-weight and length-length relationships of eight fish species from Bohai Bay, China

Length–weight and length–length relationships (LWRs and LLRs) for eight fish species collected quarterly by trawl net in Bohai Bay, China, were estimated in a total of 1,395 specimens from 2012 to 2015. These were Pholis fangi, Setipinna taty, Engraulis japonicus, Larimichthys polyactis, Thryssa kammalensis, Scomberomorus niphonius, Johnius grypotus and Sardinella zunasi. The LWRs for the last two fish species are first reports for FishBase.

여수와 진도 연안 낭장망에 어획된 어류 혼획률 월 변화 및 미성어 비율

We examined monthly changes in the rate of fishes by-caught by gape net with wings and their immature ratio in the coast of Yeosu and Jindo Island, Korea. A minus correlation between bycatch rate, the ratio of fishes except for anchovy, Engraulis japonicus, to all fishes collected by gape net with wings, and individuals of the collected anchovy was significantly observed, implying that as the anchovy catch decreased and the bycatch rate increased. Immature ratios by the dominant bycatch species during the study is the following; Leiognathus nuchalis was 72.7~99.0%, Sphyraena pinguis was 84.0%, Sardinella zunasi was 90.0%, others (Leptocephalus, Trichiurus lepturus, Ammodytes personatus, Sphyraena pinguis, Trachurus japonicas, Mugil cephalus and Erisphex pottii) were 100.0%. In order to decrease the high bycatch rates of immature fishes in spring and autumn, our study suggested increasing of codend mesh size and developing suitable bycatch reduction devices in a gape net with wings.

진도 연안 낭장망에 어획된 어류의 종조성

【Species composition of the fish in the coastal waters of Jindo was determined using monthly sample collection by a gape net with wings in 2014. Of a total of 41 fishes collected, the dominant species were Engraulis japonicus, Thryssa kammalensis, Sardinella zunasi, Leiognathus nuchalis, Amblychaeturichthys hexanema, Neosalanx anderssoni, Acanthogobius flavimanus. The former three species were the migratory species and the other four species were the resident species. These 7 fishes accounted for 99.6% of the total number of individuals collected. Monthly species composition did not show a clear seasonal trend. The peak number of individuals occurred in May, lowest in November. Fish were divided into four groups by the cluster analysis.】

완도 연안 낭장망에 채집된 어류 군집구조의 12년 전후 변화

Our aim was to compare the community structure of fish in the coast of Wando Island between 2001 and 2013. Using a gape net with wings, we collected 61 taxa, wherein the most dominant species was Engraulis japonicus. The sea temperature in the middle layer of the survey station in 2001 (after June) was obviously higher than that in 2013, which was < <TEX>$20^{\circ}C$</TEX>. Except for Thryssa kammalensis in 2013, the log transformed individuals of seven dominant species, selected using a SIMPER (similarity-percentages procedure) analysis, decreased. Decreases in the individuals of Gobiidae spp., the warm-water species Trichiurus japonicus and Conger myriaster, and the migratory species Syngnathus schlegeli, Setipinna taty and Sardinella zunasi, which arrive in the southern coastal waters of Korea during summer-autumn, could be due to decreasing sea temperature in 2013. Thus, fish species diversity, estimated from rarefaction and k-dominance curves, declined in the coastal waters of Wando Island from 2001 to 2013, resulting in a significant difference in fish community structure.

전남지역 낭장망의 어구 및 어획물 비교

This study was carried out to compare the regional fishing gears and catches of the gape net with wings used in Jeonnam, Korea. The total length of the gear used in Yeosu, Wando and Jindo was 107.0m, 64.0m, 52.8m, and the size of codend was 4.3mm. 7.8mm. 9.8mm, respectively. The total number of bycatch species from anchovy (Engraulis japonicus) catches in Yeosu, Wando, and Jindo during the survey period were 21, 13, and 13 species. A total of individuals of anchovy accounted for over 90% out of total catches in all survey areas. The proportion of anchovy individuals was constantly high up to October in Yeosu, but it showed a sharp reduction to 18% in October in Wando with the increase of the individuals of Kammal thryssa (Thryssa kammalensis) and Big eyed herring (Sardinella zunasi). In Jindo, individuals of anchovy occupied over 99.8% out of total catches up to August. Since August, the number of individuals of Big eyed herring (Sardinella zunasi), Kammal thryssa (Thryssa kammalensis), and Slimy (Leiognathus nuchalis) has increased while the number of anchovy individuals were decreased.

莱州湾及黄河口水域鱼类群落结构的季节变化

PDF HTML阅读 XML下载 导出引用 引用提醒 莱州湾及黄河口水域鱼类群落结构的季节变化 DOI: 10.5846/stxb201303060354 作者: 作者单位: 上海海洋大学海洋科学学院 上海;山东省渔业资源与生态环境重点实验室 中国水产科学研究院黄海水产研究所 青岛;山东省渔业资源与生态环境重点实验室 中国水产科学研究院黄海水产研究所 青岛,山东省渔业资源与生态环境重点实验室 中国水产科学研究院黄海水产研究所 青岛;山东省渔业资源与生态环境重点实验室 中国水产科学研究院黄海水产研究所 青岛,山东省渔业资源与生态环境重点实验室 中国水产科学研究院黄海水产研究所 青岛,山东省渔业资源与生态环境重点实验室 中国水产科学研究院黄海水产研究所 青岛,山东省渔业资源与生态环境重点实验室 中国水产科学研究院黄海水产研究所 青岛 作者简介: 通讯作者: 中图分类号: 基金项目: 国家重点基础研究发展计划资助项目（2011CB409805，2010CB951204）；山东省优秀中青年科学家科研奖励基金资助项目（BS2012HZ030）；山东省泰山学者专项基金资助项目 Seasonal variations in fish community structure in the Laizhou Bay and the Yellow River Estuary Author: Affiliation: College of Marine Sciences, Shanghai Ocean University, Shanghai;Shandong Provincial Key Laboratory of Fishery Resources and Ecological Environment, Yellow Sea Fisheries Research Institute, CAFS, Qingdao,,,,Shandong Provincial Key Laboratory of Fishery Resources and Ecological Environment, Yellow Sea Fisheries Research Institute, CAFS, Qingdao Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:根据2011年5月-2012年4月对莱州湾及黄河口水域9个航次的渔业底拖网调查数据，对该水域鱼类群落结构特征及其季节变化进行了初步研究。结果表明：莱州湾及黄河口水域共捕获鱼类62种，隶属于11目、34科、53属，主要由暖水种和暖温种组成，其中鲈形目种类最多（37种），其次是鲉形目（7种）和鲽形目（6种）。春季优势种包括矛尾鰕虎鱼（Chaeturichthys stigmatias）、鲱衔（Callionymus beniteguri）、短吻红舌鳎（Cynoglossus joyneri）、矛尾复鰕虎鱼（Synechogobius hasta）和方氏云鳚（Enedrias fangi），其渔获量占总渔获量的70.8%；夏季包括矛尾鰕虎鱼、斑鰶（Konosirus punctatus）、鲱衔和短吻红舌鳎，占总渔获量的68.1%；秋季包括矛尾鰕虎鱼、赤鼻棱鳀（Thrissa kammalensis）、鳀（Engraulis japonicus）、青鳞小沙丁鱼（Sardinella zunasi）、斑鰶、小黄鱼（Larimichthys polyactis）和矛尾复鰕虎鱼，占总渔获量的87.1%。平均单位时间渔获量存在显著季节变化，以秋季最高（22.63kg/h），其次是夏季（16.75kg/h），春季最低（1.29kg/h）。春季（5月）平均单位时间渔获量为0.69kg/h，为1959年、2003年、2006年和2008年春季（5月）的0.3%、0.3%、1.7%和541.2%，鱼类资源量虽有所回升，但总体呈大幅下降的趋势。鱼类种类数、丰富度指数和多样性指数夏季较高，秋季次之，春季最低，但是以渔获尾数计算的均匀度指数，夏季最大，春季最小，以渔获量计算的均匀度指数则相反，且丰富度指数和多样性指数与表层温度呈极显著相关（P<0.01），丰富度指数和均匀度指数与表层盐度呈极显著相关（P<0.01）。 Abstract:Seasonal variations in fish community structure characteristics in the Laizhou Bay and the Yellow River Estuary were analyzed by combining data collected from bottom trawl surveys on 9 different voyages in May-November, 2011 and March-April, 2012 with existing historical data. A total 62 fish species were caught, belonging to 11 orders and 34 families, which mainly comprised warm water and warm temperate species. The Perciformes were the most abundant (37 species), followed by the Scorpaeniformes (7 species) and Pleuronectiformes (6 species). In terms of total catch per haul (kg) and the number per haul, warm temperate species were the most abundant followed by warm water species and cold temperate species. The warm temperate species catches were highest in spring in the coastal region, whereas warm water and warm temperate species catches were higher in summer and autumn, which were mostly distributed in the northeast Laizhou Bay deep-water area in autumn. Warm temperate species were widely distributed in summer and warm water species were mostly distributed in the coastal region of southern Laizhou Bay. The dominant species in spring were mainly non-commercial demersal fish; Chaeturichthys stigmatias, Callionymus beniteguri, Synechogobius hasta, and Enedrias fangi accounted for 66.4% of the total catch. The dominant species in summer were also mainly non-commercial demersal fish species; C. stigmatias and C. beniteguri accounted for 44.6% of the total catch. While in autumn, the dominant species were mainly commercial pelagic fish; Engraulis japonicus, Sardinella zunasi, and Konosirus punctatus accounted for 40.8% of the total catch. According to the dominance curve, the dominant species were most prominent in summer, autumn, and spring in that order. The catch per haul exhibited significant seasonal variation, being highest in autumn (22.66 kg/h) followed by summer (16.75kg/ h) then spring (1.29 kg/ h). The average catch per haul of the dominant species in spring (May) was 0.69 kg/h, which is 0.3%, 0.3%, 1.7%, and 541.2% of the surveys in the spring (May) of 1959, 2003, and 2008, respectively. Despite the small increase in fish resources, the overall trend shows a substantial decrease. Species composition exhibited higher similarities in adjacent months, i.e. each month of the same season and the months of summer and autumn. The number of fish species and abundance and diversity indices were all highest in summer, followed by autumn and then spring. However, the evenness index calculated by number was highest in summer and lowest in spring, this trend was inversed when the index was calculated by weight. The species abundance and diversity indices were significantly correlated with sea surface temperature (P<0.01). The species abundance index and evenness index were significantly correlated with sea surface salinity (P<0.01). 参考文献 相似文献 引证文献

Determination of the trophic levels of four fish species in Engraulidae and Clupeidae in Laizhou Bay based on stable carbon and nitrogen isotopes

Long-term overfishing and environmental pollution has led to a high degree of change in Laizhou Bay fisheries resource structures. Since 1980, small pelagic fish have become the new dominant species in this area.These small pelagic fish play a connecting role in the food chain and are often one of the key groups in marine ecosystems. Research on the trophic level of Engraulidae and Clupeidae fish in Laizhou Bay based on stomach content analysis has provided useful but dated information. More up-to-date research is now necessary. Based on bottom trawl surveys in Laizhou Bay during summer and autumn, 2011, the stable isotope signatures of four Engraulidae and Clupeidae species revealed that the stable carbon isotope ratios ranged from 21.97‰ to 11.67‰,while stable nitrogen isotope ratios ranged from 8.54‰ to 15.95‰. ANOVA analysis revealed that δ13C and δ15N varied significantly among the four species(P0.05). Linear regression analysis between fork length and stable isotopic ratios showed that Sardinella zunasi and Konosirus punctatus had significant ontogenetic variation in terms of δ15N(P0.05), while Setipinna taty and Thrissa kammalensis did not(P0.05). The S. zunasi trophic level ranged from 2.80 to 4.88, with the average being 3.52±0.46; the K. punctatus trophic level ranged from 2.71to 4.29, with the average being 3.34±0.33; the T. kammalensis trophic level ranged from 3.38 to 4.42, with the average being 3.97±0.28; the S. taty trophic level ranged from 3.28 to 4.13, with the average being 3.76±0.23.According to the stable carbon and nitrogen isotope results, we can draw the following conclusions:(1) The stable carbon isotope values showed that K. punctatus trophic level range( 20.92 to 11.67) almost covers that of the remaining three species( 21.97 to 16.8), meaning that K. punctatus inhabits a wide depth range which is different to that of other pelagic fish;(2) The K. punctatus trophic level decreases with increasing fork length while that of S. zunasi increases with increasing fork length, no such changes were observed in the other two species;(3) The T. kammalensis trophic level is about 0.7 times larger than that reported from the traditional stomach content analysis, which may be related to increased feeding on shrimp. The trophic level of the other three species was slightly higher according to the stable isotope results, but not significantly so.

진도해역 낭장망의 어획물 실태에 따른 어업관리 방안

In this study, we conducted field surveys to investigate and analyze species and length composition of catch from gape net with wings being set in two areas - Masari, Supomri - located in southern part of Jin-do for understanding fishing characteristics of gape net with wings fishery from March to September of 2011. And with those results, we attempted to propose fishery management strategy to harvest fisheries resources continuously. Catch obtained from field surveys comprised total 78 species, which accounted for 53 species of fish, 20 species of crustacean, 4 species of cephalopod and one of polychaete. As to species composition in weight, it showed that there was 88.5% for pisces, 9.0% for cephalopoda and 2.5% for crustacea. As to catch specifics by area, there was 36 species (596,891 individual, 456,551g) of pisces, 17 species (35,815 individual, 12,909g) of crustacea and 3 species (2,876 individual, 3,004g) of cephalopoda in Masari area. In Supumri area, there was 41 species (396,898 individual, 281,457g) of pisces, 15 species (16,113 individual, 7,772g) of crustacea and 4 species (6,792 individual, 72,329g) of cephalopoda and one polychaeta (36 individual, 11g). Catch of anchovy by month recorded on high level on June, July, September in both areas. When considering size composition by month, it was found that new populations recruit to these fishing grounds on June and September. Most of bycatch species including hairtail (Trichiurus lepturus), dotted gizzard shad (Konosirus punctatus), conger eel (Leptocephalous), Pacific sandlance (Ammodytes personatus), horse mackerel (Trachurus japonicus) were juvenile, and grass puffer (Takifugu niphobles), Kammal thryssa (Thryssa kammalensis), Japanese sardinella (Sardinella zunasi) were also small in size. As a result, it is considered that gape net with wings fishery which is likely to catch juvenile needs to be set fishing prohibit period for conserving above stocks during the period excluding main fishing periods of anchovy or fisheries management such as expanding mesh size for preventing juvenile catch.

Structure and distribution of fish resources in the Yellow Sea off Shandong during spring and autumn 2006

Marine ecosystems,particularly the structure of fish assemblages are increasingly affected by human activity.We evaluated the structure and distribution of fish resources using data collected by trawl surveys in May and October of 2006 in the Yellow Sea off Shandong(35o00?—38o00?N,120o30?—124o00?E).We collected sam-ples at 45 sites and standardized the survey data using the sweep area and capture coefficient.The capture coeffi-cient was set to 0.55 for pelagic fish,0.35 for demersal fish,and 0.25 for benthic fish.The abundance index was much higher in the coastal waters than in the deeper,offshore waters in spring.During this time,most species mi-grate to the coastal regions to spawn.In addition,winter-spawning species,such as pacific sandeel(Ammodytes personatus),were still feeding in the coastal waters during the time of the surveys.In autumn,the abundance in-dex was slightly higher in the coastal waters than in the offshore areas.The highest abundance index was meas-ured in Haizhou Bay,both in spring and autumn.We collected a total of 61 species,50 in spring and 50 in autumn.The structure of fish resources was analyzed based on economic value,habitat layer,and temperature-adapted components.The lower-valued species were dominant in spring and autumn.The lower-valued species constituted 91.0% of the biomass in spring and 80.9% in autumn.The demersal fish were dominant in spring(76.7% of the biomass) whereas pelagic fish,dominated in autumn(75.1% of the biomass).The biomass was dominated by cold-water species(75.0%) in spring and warm-water species(50.1%) in autumn.In spring,the top 10 species by biomass were pacific sandeel,Japanese anchovy(Engraulis japonicas),fang's blenny(Pholis fangi),pacific cod(Gadus macrocephalus),spotted mackerel(Scomberomorus niphonius),smallhead hairtail(Eupleurogrammus punctamanus),yellow croaker(Larimichthys polyactis),silver pomfret(Pampus argenteus),scaly hairfin anchovy(Setipinna taty),and grassfish(Liparis tanakae).Conversely,the assemblage was dominated by Japanese anchovy,Japanese sardinella(Sardinella zunasi),pacific sandeel,yellow croaker,rednose anchovy(Thrissa kammalensis),silver pomfret,gizzard shad(Konosirus punctatus),smallhead hairtail,spotted mackerel,and scaly hairfin an-chovy in autumn.We used the Normalized Biomass Size Spectra(NBSS) to compare the community composition between months and years.Species that contributed 0.01% to the total biomass were excluded.The slope was regressed by log2(total biomass of every weight class/10) to log2(upper limit of average individual weight class).The NBSS slope was ?1 in both spring and autumn,suggesting the biomass decreased as individual body weight increased.The average individual body weight was 2.36 g/individual in spring and 3.34 g/individual in autumn.The proportion of species whose average individual body weight was 10 g was 95.74% in spring and 82.09% in autumn.Compared with the 1980s,we conclude that: 1) The low-valued species are more dominant,2) though there has been a partial recovery in the fishery,the larger,high value species have not recovered at the same rate,and 3) the dominant species has changed significantly due to an increase in the number of fang's blenny.Given our results,we propose an earlier beginning to the closed fishing period during summer.

Non-functional hermaphroditism in three species of Clupeiformes from Tokyo Bay, Japan

Intersexual gonads were detected in three clupeiform species, Sardinops melanostictus, Sardinella zunasi and Englaulis japonicus, collected in Tokyo Bay off Yokohama City, Japan, of which appearance rates were 18.2, 34.6 and 33.9 %, respectively. While spermatogenesis proceeded normally in these individuals, previtellogenic stage oocytes were detected outside of the testes in the hermaphrodites, appearing as a single cell or small clusters. The results suggest that these species are non-functional hermaphrodites. As intersexual gonads have been reported in other clupeiform species collected before significant pollution and/or at sites far from urban influences, such non-functional hermaphrodites may be common occurrence in the order. However, high rates of hermaphrodite appearance also suggest the possibility that the development of these oocytes were induced by environmental estrogens.

서해 하구역과 연안역 유영생물의 군집구조 비교

To elucidate the species compositions of estuarine and inshore fauna and compare productivities between them, catch were collected by bag nets in the Han River estuary off Ganghwa Island and the inshore waters off Jangbong Island for 24 hours at the spring tide from March to December 2010. Community structures of nekton assemblages were different with area, month, taxonomic groups. Although the diversity of estuarine nekton assemblage was lower than that of inshore nekton assemblage, the productivity of nekton assemblage in estuary was higher than that in the inshore waters. Nekton assemblages were distributed according to habitat environment: the estuarine species, Coilia mystus, Chelon haematocheilus, Collichthys lucidus were prominent in the Han River estuary off Ganghwa Island, and marine species, Thryssa kammalensis, Sardinella zunasi, Portunus trituberculatus were prominent in the inshore waters off Jangbong Island. Palaemon gravieri, Exopalaemon carinicauda, Synechogobius hasta were inhabited in both waters. The health assessment of estuarine ecosystem based on scientific research will be contributed to the effective management of estuary with determination of order and direction in policy.

Temporal occurrence patterns and habitat use of fish in the Mangyeong estuary on the western coast of Korea in 2003, before dike enclosure

We documented the temporal occurrence patterns and habitat use of fish in the Mangyeong River estuary on the western coast of Korea from February to December 2003 based on monthly samples collected with a stow net. A total of 46 fish species were collected during the study period. Chelon haematocheilus, Konosirus punctatus, Neosalanx jordani, Sardinella zunasi, Synechogobius hasta, and Thryssa kammalensis were the predominate species, accounting for 84.4% of the collected fish. We classified the fish as brackish water (BF), coastal migratory (CMF), diadromous (DF), or freshwater (FF) fish. BF such as C. haematocheilus, S. hasta, and Coilia nasus were the most abundant and were collected almost year-round. As water temperatures increased in spring, adult CMF, such as K. punctatus, S. zunasi, T. kammalensis, T. adelae, Johnius grypotus, Miichthys miiuy, and Larimichthys polyactis, entered the estuary. In summer, large numbers of their juvenile offspring were caught, indicating a peak in fish abundance. The juveniles grew in the estuary before moving out to deeper waters for overwintering. Diadromous juveniles, such as those of Anguilla japonica (commonly known as glass eel), were collected in the spring during their upstream migration. FF, such as Carassius cuvieri and Acheilognathus rhombeus, were collected during the rainy season. In terms of the number of species, the number of individuals, and the biomass, the ratio of BF to all other fish type classifications in the Mangyeong Estuary (without a dam) was higher than that in the Geum River estuary (with a dam). The fish assemblage in the Mangyeong Estuary still maintained estuarine characteristics before dike enclosure, providing habitats for BF, nursery grounds for CMF, and migratory pathways for DF.

Genetic differentiation of Japanese sardinella (Sardinella zunasi) populations in the Northwest Pacific revealed by ISSR analysis

Knowledge of population genetic structure plays an important role in fisheries management. In this research, Inter-Simple-Sequence-Repeat (ISSR) markers were employed to evaluate the genetic structure of Japanese sardinella (Sardinella zunasi) populations in the Northwest Pacific. Eighty seven individuals from 5 locations were screened using 4 highly polymorphic primers. A total of 173 polymorphic loci were detected out of 191 loci amplified. Small but significant genetic differentiation was detected between the Chinese and Japanese populations by both AMOVA and pairwise FST analyses, which was further supported by cluster analysis. We consider that climate change during glaciations should be responsible for the genetic differentiation. Isolation by geographic distance among populations was observed, indicating that the distance might also lead to the genetic differentiation. However, no genetic structure was found within the populations off both the Chinese and Japanese coasts, indicating a high-level along-coast gene flow, which might result from ocean current transport and common ground for over-wintering.

Determination of brominated flame retardants and brominated dioxins in fish collected from three regions of Japan

The concentrations of brominated dioxins which are polybrominated dibenzo-p-dioxins/polybrominated dibenzofurans (PBDD/DFs) and mono-bromo polychlorinated dibenzo-p-dioxins/dibenzofurans, polybrominated diphenyl ethers (PBDEs) and tetrabromobisphenol A (TBBPA) were investigated in a total of 45 fish samples collected from three regions in Japan. In the brominated dioxins, 1,2,3,4,6,7,8-heptabromodibenzofuran (HpBDF) was the most abundant congener, and it was found in seven fish samples at 0.10-25.6 pg/g wet weight (ww). The highest concentration of 1,2,3,4,6,7,8-HpBDF was found in the pike eel. Regarding other congeners, 2,3,7,8-tetrabromodibenzo-p-dioxin was detected in the sea bream at 0.02 pg/g ww, and 2,3,7,8-tetrabromodibenzofuran was detected in the conger eel at 0.03 pg/g ww. 3-Bromo-2,7,8-trichlorodibenzofuran was detected in the Sardinella zunasi and the conger eel at 0.01 pg/g ww and 0.02 pg/g ww, respectively. Using toxic equivalency factors of chlorinated dioxins, we calculated the PBDD/DFs concentrations of these fish samples at 0.001-0.256 pg TEQ/g ww. PBDEs were detected in all of the fish samples. The concentrations of total PBDEs were 0.01-2.88 ng/g ww. The seerfish and the yellowtail containd PBDEs in high concentrations. The most dominant congener in most of the fish was 2,2',4,4'-tetrabromo diphenyl ether. TBBPA was detected in 29 fish samples at 0.01-0.11 ng/g ww. The mean level of TBBPA was about one-tenth or less of the total level of PBDEs. A good correlation was obtained between total PBDEs and fat content. On the other hand, no correlation was obtained between TBBPA and fat content. The daily intakes from fish were estimated to be 0.58 ng/kg body weight (bw)/day for total PBDEs, 0.03 ng/kg bw/day for TBBPA, and 0.01 pg TEQ/kg bw/day for brominated dioxins in the case assuming that the average bw of a Japanese adult person is 50 kg and that the average fish consumption is 82 g/day. For PBDEs, the provisionally calculated value was much less than the lowest observed adverse effect level value (1 mg/kg bw/day). For brominated dioxins, the daily intake was at a very low level compared with the Japanese daily intake of polychlorinated dioxins from fish. Even if the value of PBDD/DFs is added to the amount of chlorinated dioxin exposure, it was estimated that it is less than the tolerable daily intake (4 pg TEQ/kg bw/day) in Japan.

Comparison of fish fauna in three areas of adjacent eutrophic estuarine lagoons with different salinities

Variation in fish assemblages was investigated to clarify the migration patterns and growth rates of marine, brackish and freshwater species in three adjacent areas with different salinities. In the polyhaline Lake Nakaumi, Japan, benthic fishes and crustaceans were negatively affected by oxygen depletion in the lower water under stratification during the warm seasons. On the other hand, marine and brackish species that once migrated into the Honjo Area, which is isolated from L. Nakaumi and has a homogeneous salinity structure, remained and grew there until winter. In the mesohaline Lake Shinji, two types of fishes were distinguished: one that migrated into the lake during the warmer seasons; and the other which stayed in the lake during winter. Fauna and production in L. Shinji were compared with those of a comprehensive study carried out approximately 35 years ago. For 35 years, Konosirus punctatus and Sardinella zunasi have increased in abundance, while Carassius sp. and Hypomesus nipponensis have decreased. Even with the recent acceleration in eutrophication of the lake, fish production during the warmer seasons has not declined for 35 years, but the fish fauna have drastically changed.