A wealth of literature has been published in the studies of Chinese fresh-water fish chromosomes within recent years.In this paper,we review the inter-and intraspecific genetic diversities found in Chinese fresh-water...A wealth of literature has been published in the studies of Chinese fresh-water fish chromosomes within recent years.In this paper,we review the inter-and intraspecific genetic diversities found in Chinese fresh-water fishes,and explore the characteristics and mechanisms that underline these diversities and variations. We also propose the hypothesis how the genetic diversities had evolved in the fresh-water fishes.展开更多
Phylogeny of the sinipercine fishes, their relationships with some fossils and their systematic position were studied in this paper. Consisting of 2 sister groups, the sinipercine fishes were grouped as 2 genera - Cor...Phylogeny of the sinipercine fishes, their relationships with some fossils and their systematic position were studied in this paper. Consisting of 2 sister groups, the sinipercine fishes were grouped as 2 genera - Coreoperca and Siniperca, while the genus Coreosiniperca was unwarranted for its type being a member in Siniperca, Having many special characters, Tungtingichthys was denied as the ancestor of the sinipercine fishes, however, Siniperca wusiangensis was taken as one member in Siniperca and some fossil percoids found in Japan had close relationship with sinipercine fishes. All characters of the sinipercine fishes are not concordant with that in Serranidae or Percichthyidae which leads to the conclusion that either the sinipercine fishes are not in Percichthyidae, or the defining characters of Percichthyidae listed by Gosline (1966) are wrong. But at present, we can only put the sinipercine fishes in Percichthyidae.展开更多
According to an ancient belief from Turkish, Greek, Roman, and many Europe countries, an auspicious eye can bring fortunesto the people, protect them from evil.
The hypertrophic subtropic Donghu Lake’s dense water bloom(of mainly Microcystis Anaabaena andOscillatoria)that occurred annually from the beginning of the 1970s, has disappeared since 1985. The infiuenceof planktivo...The hypertrophic subtropic Donghu Lake’s dense water bloom(of mainly Microcystis Anaabaena andOscillatoria)that occurred annually from the beginning of the 1970s, has disappeared since 1985. The infiuenceof planktivorous fishes (silver and bighead carps) on the water bloom was studied for three years usingthe enclosure method. The enclosures stocked densely with bighead and/or silver carp were free of waterbloom during the experimental period. The water bloom that appeared in the fish-free enclosures was completelyeliminated in 10-20 days by introduction of silver and/or bighead carp(grass carp was not effectivein controlling water bloom).This study showed clearly that grazing pressure by planktivorous fishes is a keyfactor in eliminating water bloom from the lake.展开更多
AIM To study the cell types,localization,distribution density and morphology of APUDcells in the intestinal mucosa of stomachlessteleost fishes.METHOD By using the peroxidase-antiperoxidase complex(PAP)immunocytochemi...AIM To study the cell types,localization,distribution density and morphology of APUDcells in the intestinal mucosa of stomachlessteleost fishes.METHOD By using the peroxidase-antiperoxidase complex(PAP)immunocytochemical staining technique theidentification,localization and morphology ofimmunoreactive(IR)endocrine cells seattered inthe intestinal mucosa of grass carp(Cyenopharyngodon idellus),black carp(Mylopharyngodon piceus)and common carp(Cyprinus carpio)were investigated with 20kinds of antisera prepared against mammalianpeptide hormones of APUD cells,and likewise byusing avidin-biotin-peroxidase complex(ABC)method those of silver carp(Hypophthalmichthys molitrix),bighead(Aristichthys nobilis),silver crucian carp(Carassius gibelio)and bluntnose black bream(Megalobrama amblyocephala)were alsostudied with 5 different antisera.Thereplacement of the first antiserum by phosphatebuffered saline(PBS)was employed as a control.IR endocrine cells were counted with asquare-mesh ocular micrometer from 10 fieldsselected randomly in every section of each partof the intestine specimen.The average numberof IR endocrine cells per mm2 was counted toquantify their distribution density.RESULT Gastrin(GAS)-,Gastric inhibitorypeptide(GIP)-,glucagon(GLU)-,glucagon-likeimmunoreactants(GLI)-,bovine pancreaticpolypeptide(BPP)-,leucine-enkephalin(ENK)-and substance P(SP)-IR endocrine cells werefound in the gut of grass carp,black carp andcommon carp,and somatostatin(SOM)-IRendocrine cells were only seen in common carp.GAS-,GIP-and GLU-IR endocrine cells werefound in the intestinal mucosa of silver carp,bighead,silver crucian carp and bluntnose blackbream.Most of IR endocrine cells had the higherdistribution density in the foregut and midgut,and were longer in shape.They had a long apicalcytoplasmic process extended to the gut lumenand a basal process extended to adjacent cellsor basement membrane and touched with it.Sometimes,the basal cytoplasmic processformed an enlarged synapse-like structure in thecontiguous part with basement membrane.Thisphenomenon provided new morphologicalevidence for neuroendocrine and paracrinesecretory function of these enteroendocrinecells.CONCLUTION At least 8 kinds of IR endocrinecells were found in the gut of stomachlessteleost species for the first time in China.TheseIR endocrine cells scattering in the gut mucosabelong to the APUD system.Among them,thehormones secreted by SP-,ENK-,SOM-and GLU-IR endocrine cells belong to the peptides of dualdistribution in the brain and gut.This providednew evidence for the concept of brain-gutpeptide.According to the cell types,distribution density,morphologicalcharacteristics and variety in shape of APUDcells in the gut of stomachless teleost fishes,itis deemed that the digestive tract of fishes isalso an endocrine organ of great importance andcomplexity.展开更多
The Cr, Zn, Cu, Cd, Pb contents were determined in Cyprinus carpio Linnaeus, Carassius auratus Linnaeus, Hypophthalmichthys molitrix and Aristichthys nobilis, which were caught from Meiliang Bay, Taihu Lake, a large, ...The Cr, Zn, Cu, Cd, Pb contents were determined in Cyprinus carpio Linnaeus, Carassius auratus Linnaeus, Hypophthalmichthys molitrix and Aristichthys nobilis, which were caught from Meiliang Bay, Taihu Lake, a large, shallow and eutrophic lake of China. The results showed that: (1) the Cr, Cu, Pb, Cd contents in the edible parts of the four fish species were much lower than Chinese Food Health Criterion (1994), but the Zn contents were higher than the Criterion; (2) Cd contents were the highest in the liver of fish, Pb contents were almost the same in all organs of fish, Cr contents mainly enriched in the skin and gonads, Zn contents were the highest in the gonad (♀), and Cu contents were the highest in the liver; (3) the total metal accumulation was the greatest in the liver and the lowest in the muscle. The total metal accumulation was the highest in C. auratus L. This investigation indicated that fish products in Taihu Lake were still safe for human consumption, but the amount consumed should be controlled under the Chinese Food Health Criterion to avoid excessive intake of Zn.展开更多
Evaluation of spatial-temporal variability of species composition and diversity in oceanic ecosystems is not easy because it is usually difficult to obtain sufficient data quantifying such variability.In this study,we...Evaluation of spatial-temporal variability of species composition and diversity in oceanic ecosystems is not easy because it is usually difficult to obtain sufficient data quantifying such variability.In this study,we examined pelagic species diversity indicators,species richness,Shannon-Wiener index of diversity and Hurlbert's species evenness,for fish assemblages from two areas(north and south) in the North Pacific Ocean(2°±12°N,178°E±165°W) during May±July 2008.The assemblages were based on data collected by an onboard scientific observer during a commercial longline fishing trip.The species richness and Shannon-Wiener diversity index of fish assemblages in the northern area were slightly higher than those in the southern area,although these differences were not significant(t test,P.0.05).Non-parametric multidimensional scaling and analysis of similarities indicated that there were significant differences in fish assemblages between the two areas(P,0.01).展开更多
Length-frequency data of eight commercial fish species in the Beibu Gulf (Golf of Tonkin), northern South China Sea, were collected during 2006-2007. Length-weight relationships and growth and mortality parameters w...Length-frequency data of eight commercial fish species in the Beibu Gulf (Golf of Tonkin), northern South China Sea, were collected during 2006-2007. Length-weight relationships and growth and mortality parameters were analyzed using FiSAT II software. Five species had isometric growth, two species had negative allometric growth, and one species had positive allometric growth. Overall, the exploitation rates of the eight species were lower in 2006 2007 than in 1997-1999: for four species (Saurida tumbil, Saurida undosquamis, Argyrosomus macrocephalus, and Nemipterus virgatus) it was lower in 2006-2007 than in 1997 1999, for two species (Parargyrops edita and Trichiurus haumela) it remained the same, and for the other two species (Trachurus japonicus and Decapterus maruadsi) it was higher in 2006~007 than in 1997-1999. The exploitation rates might have declined because of the decline in fishing intensity caused by high crude oil prices. The optimum exploitation rate, estimated using Beverton-Holt dynamic pool models, indicated that although fishes in the Beibu Gulf could sustain high exploitation rates, the under-size fishes at first capture resulted in low yields. To increase the yield per recruitment, it is more effective to increase the size at first capture than to control fishing effort.展开更多
Spatial distribution and abundance of small fishes were studied in autumn 2007 in the Xiaosihai Lake, a shallow lake along the middle reach of the Changjiang (Yangtze) River. Based on the plant cover, the lake was d...Spatial distribution and abundance of small fishes were studied in autumn 2007 in the Xiaosihai Lake, a shallow lake along the middle reach of the Changjiang (Yangtze) River. Based on the plant cover, the lake was divided into three major habitats: Myriophyllum spicaturn habitat (MS habitat), Trapa bispinosa habitat (TB habitat), and non-vegetation habitat (NV habitat). A modified pop-net was used for quantitative sampling of small fishes in the three habitats, and the Zippin's removal method was used for estimating densities of the small fishes. A total of 13 species belonging to 5 families were collected, with 11 species in MS habitat, 7 species in TB habitat, and 5 species in NV habitat. Habitat type had significant effect on the spatial distribution of small fishes. The Shannon-Wiener diversity index in the MS, TB and NV habitats were 1.28, 0.56 and 0.54, respectively. The total density and biomass of small fishes were significantly higher in the MS habitat (13.68 ind/m^2 and 4.44 g/m^2) than in the TB habitat (1.41 ind/m^2 and 0.54 g/m^2) and the NV habitat (1.08 ind/m^2 and 0.40 g/m^2), and were not significantly different between the TB habitat and the NV habitat. Water depth had no significant effect on spatial distribution of the small fishes. It was suggested that vegetation type played an important role in habitat selectivity of small fishes, and the presence of submersed vegetation should be of significance in the conservation of small fish diversity.展开更多
The relationship between the spatiotemporal distribution of three dominant small pelagic fishes,including chub mackerel(Scomber japonicus),horse mackerel(Trachurus trecae)and round sardinella(Sardinella aurita),and th...The relationship between the spatiotemporal distribution of three dominant small pelagic fishes,including chub mackerel(Scomber japonicus),horse mackerel(Trachurus trecae)and round sardinella(Sardinella aurita),and the environmental factors in Mauritanian waters were analyzed by using 4 years of logbook data of commercial purse seine fisheries to improve the efficiency of fishery and management of sustainable exploitation.A Tweedie-generalized additive model(GAM)of 8-day average catches and the monthly geostatistical analysis of daily catches were used in this study to analyze the influence of environmental factors on catch per unit of effort(CPUEs)and to map the spatial distribution of three mixed dominant small pelagic fishes,respectively.A 10'×10' grid was used,and environmental factors were processed from remote sensing,including 8-day average sea surface temperature(SST),the nearest distance between SST fronts and CPUE position(Df),chlorophyll-a(Chl-a)concentration,salinity,and eddy kinetic energy.Results showed that 1)the distribution of three dominant small pelagic fishes might be related to the intensity of upwelling in Mauritanian waters;2)oceanic fronts might play a key role in the ecology of chub mackerel,horse mackerel,and round sardinella;3)Chl-a concentration might be associated with the feeding grounds of chub mackerel;4)the target species distribution appeared sensitive to gradient changes in the amount of salinity;5)three zones(northern,central,and southern)with variable abundances were delineated;and 6)a high concentration of the center of gravity in the central zone might be related to the strong upwelling of nutrient-rich waters.This study can provide new insights to enhance the fishery efficiency and sustainable exploitation management of purse seiners in certain area off Mauritania.展开更多
In this review, I explore the effects of both social organization and the physical environment, specifically habitat complexity, on the brains and behavior of highly visual African cichlid fishes, drawing on examples ...In this review, I explore the effects of both social organization and the physical environment, specifically habitat complexity, on the brains and behavior of highly visual African cichlid fishes, drawing on examples from primates and birds where appropriate. In closely related fishes from the monophyletic Ectodinii clade of Lake Tanganyika, both forces influence cichlid brains and behavior. Considering social influences first, visual acuity differs with respect to social organization (monogamy versus polygyny). Both the telencephalon and amygdalar homologue, area Dm, are larger in monogamous species. Monogamous species are found to have more vasotocin-immunoreactive cells in the preoptic area of the brain. Habitat complexity also influences brain and behavior in these fishes. Total brain size, telencephalic and cerebellar size are positively correlated with habitat complexity. Visual acuity and spatial memory are enhanced in cichlids living in more complex environments. However habitat complexity and social forces affect cichlid brains differently. Taken together, our field data and plasticity data suggest that some of the species-specific neural effects of habitat complexity could be the consequence of the corresponding social correlates. Environmental forces, however, exert a broader effect on brain structures than social ones do, suggesting allometric expansion of the brain structures in concert with brain size and/or co-evolntion of these structures [Current Zoology 56 (1): 144-156, 2010].展开更多
Heavy metal concentrations of Ni, Mg, Co, Cr, Cd and Cu were investigatedusing flame Atomic Absorption Spectrophotometer (AAS) in the liver, kidney, muscle, scale, gonad, gill and stomach of Cheilinus trilobatus fish ...Heavy metal concentrations of Ni, Mg, Co, Cr, Cd and Cu were investigatedusing flame Atomic Absorption Spectrophotometer (AAS) in the liver, kidney, muscle, scale, gonad, gill and stomach of Cheilinus trilobatus fish species from the northern Gulf of Aqaba. Cheilinus trilobatus fish species were collected during the period May to August 2013. The results indicated significant differences between different organs of Cheilinus trilobatus for Ni (p = 0.0002), Fe (p = 0.0213), Co (p p Cheilinus trilobatus and its length. The levels of metal concentration of the present study were generally lower or within the ranges of those found in the fish of the Red Sea. After all, Cheilinus trilobatus fish species was found to be safe for consumption and do not pose a significant threat to the health of human consumers.展开更多
Compound-specific stable isotope analysis of individual amino acids(CSIA-AA)has been widely used in ecological and biogeochemical studies.It has been proven to be powerful in tracing the diet sources and trophic inter...Compound-specific stable isotope analysis of individual amino acids(CSIA-AA)has been widely used in ecological and biogeochemical studies.It has been proven to be powerful in tracing the diet sources and trophic interactions.However,assessing the N sources of mesopelagic fishes has been inconclusive because the mesopelagic fishes’unique domain(water depth ranged from 0 to 1000 m)and unresolved nitrogen isotopes of various forms.This study proposes a new method for coupling instruments(ion chromatography and PreconIRMS)and chemical method of oxidation-reduction of amino acids,and also combinedδ15N of AAs withδ13C of fatty acids(FAs)to analyze the trophic interactions of mesopelagic fishes in the South China Sea(SCS).AAs were isolated by ion chromatography with high peak resolution and collected by an automated fraction collector.The chemical method then converted the AAs into N2 O with a robust oxidation yields and suitable molar ratio of NH2 OH to.Finally,theδ15N of AAs at 20 nmol were measured with a reasonable precision(<0.6‰).With this method,this study report the first batch high precisionδ15N of AAs andδ13C of FAs of mesopelagic fishes collected from SCS.Diaphus luetkeni,Chauliodus minimus and Bathygadus antrodes showed similarδ13C values of 20:4 n-6(~-28‰),while Argyropelecus affinis and Stomias had similar values(~-32‰).These results reflect that mesopelagic fishes had complex diet sources.An increase of 4‰inδ15N of glutamic acid(Glu)was found between piscivorous and planktivorous fishes,which might suggest a trophic discrimination factor of mesopelagic fishes in the SCS.This study usedδ13C of 20:4 n-6 to reveal the diet sources of mesopelagic fishes andδ15N of Glu to clarify trophic level between piscivorous and planktivorous fishes.Thus,this combinative method could therefore ultimately be applied in a variety of deep-sea ecosystem.展开更多
Accurate species identification is a key component of biodiversity research.DNA barcoding is an effective molecular method used for fish species identification.We aimed to study the DNA barcoding of fish in Zhoushan c...Accurate species identification is a key component of biodiversity research.DNA barcoding is an effective molecular method used for fish species identification.We aimed to study the DNA barcoding of fish in Zhoushan coastal waters,explore the differences and applicability of two gene fragments(12S rRNA and COI)of DNA barcoding in fish species identification,and established a comprehensive fish barcoding reference database.Two hundred and eighty-seven captured fish samples from Zhoushan coastal waters were identified using morphological characteristics and DNA barcoding.A total of 26412S rRNA sequences(belonging to eight orders,31 families,55 genera,and 66 species)and 188 COI sequences(belonging to seven orders,30 families,48 genera,and 58 species)were obtained.The lengths of the 12S rRNA sequences ranged from 165 to 178 bp,and the guanine-cytosine(GC)content was 45.37%.The average 12S rRNA interspecific and intraspecific genetic distances(K2P)were 0.10%and 26.66%,respectively.The length of the COI sequence ranged 574–655 bp,and the content of GC was 45.97%.The average 12S rRNA interspecific and intraspecific genetic distances(K2P)were 0.16%and 27.45%,respectively.The minimum interspecific genetic distances of 12S rRNA and COI(1.23%and 1.86%)were both greater than their maximum intraspecific genetic distances(2.42%and 8.66%).Three molecular analyses(NJ tree,ABGD,and GMYC)were performed to accurately identify and delineate species.Clustering errors occurred when the 12S rRNA sequences were delimited using the NJ tree method,and the delimitation results of ABGD and GMYC are consistent with the final species identification results.Our results demonstrate that DNA barcoding based on 12S rRNA and COI can be used as an effective tool for fish species identification,and 12S rRNA has good application prospects in the environmental DNA(eDNA)metabarcoding of marine fish.展开更多
Analysis of stomach contents of samples of clupeid fiishes (Japanese anchovy, half-fin anchovy, zunas’ scaled sardine, rednosed glassnose and tapertail anchovy) collected from the catches of a 1982-1984 fishery resou...Analysis of stomach contents of samples of clupeid fiishes (Japanese anchovy, half-fin anchovy, zunas’ scaled sardine, rednosed glassnose and tapertail anchovy) collected from the catches of a 1982-1984 fishery resource survey showed they are zooplanktonivorous. Similar food groups, such as copepoda, Chaetognatha, Amphipoda and Mysidacea were found in the stomach. Dietary similarity coefficients were studied to evaluate the degree of similarity in the dietary species-pairs.Sea-sonal variation is discussed.展开更多
文摘A wealth of literature has been published in the studies of Chinese fresh-water fish chromosomes within recent years.In this paper,we review the inter-and intraspecific genetic diversities found in Chinese fresh-water fishes,and explore the characteristics and mechanisms that underline these diversities and variations. We also propose the hypothesis how the genetic diversities had evolved in the fresh-water fishes.
文摘Phylogeny of the sinipercine fishes, their relationships with some fossils and their systematic position were studied in this paper. Consisting of 2 sister groups, the sinipercine fishes were grouped as 2 genera - Coreoperca and Siniperca, while the genus Coreosiniperca was unwarranted for its type being a member in Siniperca, Having many special characters, Tungtingichthys was denied as the ancestor of the sinipercine fishes, however, Siniperca wusiangensis was taken as one member in Siniperca and some fossil percoids found in Japan had close relationship with sinipercine fishes. All characters of the sinipercine fishes are not concordant with that in Serranidae or Percichthyidae which leads to the conclusion that either the sinipercine fishes are not in Percichthyidae, or the defining characters of Percichthyidae listed by Gosline (1966) are wrong. But at present, we can only put the sinipercine fishes in Percichthyidae.
文摘According to an ancient belief from Turkish, Greek, Roman, and many Europe countries, an auspicious eye can bring fortunesto the people, protect them from evil.
基金This work was supported by FEBL(State Key Laboratory for Freshwater Ecology and Biotechnology of China)fundsNational Natural Science Foundation of China (Grant NO.3937014)
文摘The hypertrophic subtropic Donghu Lake’s dense water bloom(of mainly Microcystis Anaabaena andOscillatoria)that occurred annually from the beginning of the 1970s, has disappeared since 1985. The infiuenceof planktivorous fishes (silver and bighead carps) on the water bloom was studied for three years usingthe enclosure method. The enclosures stocked densely with bighead and/or silver carp were free of waterbloom during the experimental period. The water bloom that appeared in the fish-free enclosures was completelyeliminated in 10-20 days by introduction of silver and/or bighead carp(grass carp was not effectivein controlling water bloom).This study showed clearly that grazing pressure by planktivorous fishes is a keyfactor in eliminating water bloom from the lake.
基金the National Natural Science Foundation of China.No.39070666.
文摘AIM To study the cell types,localization,distribution density and morphology of APUDcells in the intestinal mucosa of stomachlessteleost fishes.METHOD By using the peroxidase-antiperoxidase complex(PAP)immunocytochemical staining technique theidentification,localization and morphology ofimmunoreactive(IR)endocrine cells seattered inthe intestinal mucosa of grass carp(Cyenopharyngodon idellus),black carp(Mylopharyngodon piceus)and common carp(Cyprinus carpio)were investigated with 20kinds of antisera prepared against mammalianpeptide hormones of APUD cells,and likewise byusing avidin-biotin-peroxidase complex(ABC)method those of silver carp(Hypophthalmichthys molitrix),bighead(Aristichthys nobilis),silver crucian carp(Carassius gibelio)and bluntnose black bream(Megalobrama amblyocephala)were alsostudied with 5 different antisera.Thereplacement of the first antiserum by phosphatebuffered saline(PBS)was employed as a control.IR endocrine cells were counted with asquare-mesh ocular micrometer from 10 fieldsselected randomly in every section of each partof the intestine specimen.The average numberof IR endocrine cells per mm2 was counted toquantify their distribution density.RESULT Gastrin(GAS)-,Gastric inhibitorypeptide(GIP)-,glucagon(GLU)-,glucagon-likeimmunoreactants(GLI)-,bovine pancreaticpolypeptide(BPP)-,leucine-enkephalin(ENK)-and substance P(SP)-IR endocrine cells werefound in the gut of grass carp,black carp andcommon carp,and somatostatin(SOM)-IRendocrine cells were only seen in common carp.GAS-,GIP-and GLU-IR endocrine cells werefound in the intestinal mucosa of silver carp,bighead,silver crucian carp and bluntnose blackbream.Most of IR endocrine cells had the higherdistribution density in the foregut and midgut,and were longer in shape.They had a long apicalcytoplasmic process extended to the gut lumenand a basal process extended to adjacent cellsor basement membrane and touched with it.Sometimes,the basal cytoplasmic processformed an enlarged synapse-like structure in thecontiguous part with basement membrane.Thisphenomenon provided new morphologicalevidence for neuroendocrine and paracrinesecretory function of these enteroendocrinecells.CONCLUTION At least 8 kinds of IR endocrinecells were found in the gut of stomachlessteleost species for the first time in China.TheseIR endocrine cells scattering in the gut mucosabelong to the APUD system.Among them,thehormones secreted by SP-,ENK-,SOM-and GLU-IR endocrine cells belong to the peptides of dualdistribution in the brain and gut.This providednew evidence for the concept of brain-gutpeptide.According to the cell types,distribution density,morphologicalcharacteristics and variety in shape of APUDcells in the gut of stomachless teleost fishes,itis deemed that the digestive tract of fishes isalso an endocrine organ of great importance andcomplexity.
基金Projects supported by the National Natural Science Foundation of China(No.40673078,40203007).
文摘The Cr, Zn, Cu, Cd, Pb contents were determined in Cyprinus carpio Linnaeus, Carassius auratus Linnaeus, Hypophthalmichthys molitrix and Aristichthys nobilis, which were caught from Meiliang Bay, Taihu Lake, a large, shallow and eutrophic lake of China. The results showed that: (1) the Cr, Cu, Pb, Cd contents in the edible parts of the four fish species were much lower than Chinese Food Health Criterion (1994), but the Zn contents were higher than the Criterion; (2) Cd contents were the highest in the liver of fish, Pb contents were almost the same in all organs of fish, Cr contents mainly enriched in the skin and gonads, Zn contents were the highest in the gonad (♀), and Cu contents were the highest in the liver; (3) the total metal accumulation was the greatest in the liver and the lowest in the muscle. The total metal accumulation was the highest in C. auratus L. This investigation indicated that fish products in Taihu Lake were still safe for human consumption, but the amount consumed should be controlled under the Chinese Food Health Criterion to avoid excessive intake of Zn.
基金Supported by the China National Fishery Observer Programthe Shanghai Leading Academic Discipline Project (No. S30702)
文摘Evaluation of spatial-temporal variability of species composition and diversity in oceanic ecosystems is not easy because it is usually difficult to obtain sufficient data quantifying such variability.In this study,we examined pelagic species diversity indicators,species richness,Shannon-Wiener index of diversity and Hurlbert's species evenness,for fish assemblages from two areas(north and south) in the North Pacific Ocean(2°±12°N,178°E±165°W) during May±July 2008.The assemblages were based on data collected by an onboard scientific observer during a commercial longline fishing trip.The species richness and Shannon-Wiener diversity index of fish assemblages in the northern area were slightly higher than those in the southern area,although these differences were not significant(t test,P.0.05).Non-parametric multidimensional scaling and analysis of similarities indicated that there were significant differences in fish assemblages between the two areas(P,0.01).
基金Supported by the Chinese Ministry of Agriculture under the Investigation of Fishery Stocks in China Seas Program (No. 070404)the Special Project of the Social Commonwealth Research National Institute (Nos.2009TS08, 2010YD10)
文摘Length-frequency data of eight commercial fish species in the Beibu Gulf (Golf of Tonkin), northern South China Sea, were collected during 2006-2007. Length-weight relationships and growth and mortality parameters were analyzed using FiSAT II software. Five species had isometric growth, two species had negative allometric growth, and one species had positive allometric growth. Overall, the exploitation rates of the eight species were lower in 2006 2007 than in 1997-1999: for four species (Saurida tumbil, Saurida undosquamis, Argyrosomus macrocephalus, and Nemipterus virgatus) it was lower in 2006-2007 than in 1997 1999, for two species (Parargyrops edita and Trichiurus haumela) it remained the same, and for the other two species (Trachurus japonicus and Decapterus maruadsi) it was higher in 2006~007 than in 1997-1999. The exploitation rates might have declined because of the decline in fishing intensity caused by high crude oil prices. The optimum exploitation rate, estimated using Beverton-Holt dynamic pool models, indicated that although fishes in the Beibu Gulf could sustain high exploitation rates, the under-size fishes at first capture resulted in low yields. To increase the yield per recruitment, it is more effective to increase the size at first capture than to control fishing effort.
基金Supported by the National Natural Science Foundation of China (Nos. 30571440, 30830025)The National Key Technology R&D Program (No. 2007BAD37B03)the National Basic Research Program of China (973 Program) (No. 2007CB109205)
文摘Spatial distribution and abundance of small fishes were studied in autumn 2007 in the Xiaosihai Lake, a shallow lake along the middle reach of the Changjiang (Yangtze) River. Based on the plant cover, the lake was divided into three major habitats: Myriophyllum spicaturn habitat (MS habitat), Trapa bispinosa habitat (TB habitat), and non-vegetation habitat (NV habitat). A modified pop-net was used for quantitative sampling of small fishes in the three habitats, and the Zippin's removal method was used for estimating densities of the small fishes. A total of 13 species belonging to 5 families were collected, with 11 species in MS habitat, 7 species in TB habitat, and 5 species in NV habitat. Habitat type had significant effect on the spatial distribution of small fishes. The Shannon-Wiener diversity index in the MS, TB and NV habitats were 1.28, 0.56 and 0.54, respectively. The total density and biomass of small fishes were significantly higher in the MS habitat (13.68 ind/m^2 and 4.44 g/m^2) than in the TB habitat (1.41 ind/m^2 and 0.54 g/m^2) and the NV habitat (1.08 ind/m^2 and 0.40 g/m^2), and were not significantly different between the TB habitat and the NV habitat. Water depth had no significant effect on spatial distribution of the small fishes. It was suggested that vegetation type played an important role in habitat selectivity of small fishes, and the presence of submersed vegetation should be of significance in the conservation of small fish diversity.
基金funded by the Ministry of Agriculture and Rural Affairs of the P.R.China under Project of Fishery Exploration in 2017(No.D-8006-17-0138)
文摘The relationship between the spatiotemporal distribution of three dominant small pelagic fishes,including chub mackerel(Scomber japonicus),horse mackerel(Trachurus trecae)and round sardinella(Sardinella aurita),and the environmental factors in Mauritanian waters were analyzed by using 4 years of logbook data of commercial purse seine fisheries to improve the efficiency of fishery and management of sustainable exploitation.A Tweedie-generalized additive model(GAM)of 8-day average catches and the monthly geostatistical analysis of daily catches were used in this study to analyze the influence of environmental factors on catch per unit of effort(CPUEs)and to map the spatial distribution of three mixed dominant small pelagic fishes,respectively.A 10'×10' grid was used,and environmental factors were processed from remote sensing,including 8-day average sea surface temperature(SST),the nearest distance between SST fronts and CPUE position(Df),chlorophyll-a(Chl-a)concentration,salinity,and eddy kinetic energy.Results showed that 1)the distribution of three dominant small pelagic fishes might be related to the intensity of upwelling in Mauritanian waters;2)oceanic fronts might play a key role in the ecology of chub mackerel,horse mackerel,and round sardinella;3)Chl-a concentration might be associated with the feeding grounds of chub mackerel;4)the target species distribution appeared sensitive to gradient changes in the amount of salinity;5)three zones(northern,central,and southern)with variable abundances were delineated;and 6)a high concentration of the center of gravity in the central zone might be related to the strong upwelling of nutrient-rich waters.This study can provide new insights to enhance the fishery efficiency and sustainable exploitation management of purse seiners in certain area off Mauritania.
基金supported by NSF grants IBN-02180005 to Caroly Shumway (CAS) and IBN-021795 to Hans Hofmann (HAH)a German-American Research Networking Program grant to CAS and HAH+1 种基金the New England Aquarium to CASthe Bauer Center for Genomics Research to HAH
文摘In this review, I explore the effects of both social organization and the physical environment, specifically habitat complexity, on the brains and behavior of highly visual African cichlid fishes, drawing on examples from primates and birds where appropriate. In closely related fishes from the monophyletic Ectodinii clade of Lake Tanganyika, both forces influence cichlid brains and behavior. Considering social influences first, visual acuity differs with respect to social organization (monogamy versus polygyny). Both the telencephalon and amygdalar homologue, area Dm, are larger in monogamous species. Monogamous species are found to have more vasotocin-immunoreactive cells in the preoptic area of the brain. Habitat complexity also influences brain and behavior in these fishes. Total brain size, telencephalic and cerebellar size are positively correlated with habitat complexity. Visual acuity and spatial memory are enhanced in cichlids living in more complex environments. However habitat complexity and social forces affect cichlid brains differently. Taken together, our field data and plasticity data suggest that some of the species-specific neural effects of habitat complexity could be the consequence of the corresponding social correlates. Environmental forces, however, exert a broader effect on brain structures than social ones do, suggesting allometric expansion of the brain structures in concert with brain size and/or co-evolntion of these structures [Current Zoology 56 (1): 144-156, 2010].
文摘Heavy metal concentrations of Ni, Mg, Co, Cr, Cd and Cu were investigatedusing flame Atomic Absorption Spectrophotometer (AAS) in the liver, kidney, muscle, scale, gonad, gill and stomach of Cheilinus trilobatus fish species from the northern Gulf of Aqaba. Cheilinus trilobatus fish species were collected during the period May to August 2013. The results indicated significant differences between different organs of Cheilinus trilobatus for Ni (p = 0.0002), Fe (p = 0.0213), Co (p p Cheilinus trilobatus and its length. The levels of metal concentration of the present study were generally lower or within the ranges of those found in the fish of the Red Sea. After all, Cheilinus trilobatus fish species was found to be safe for consumption and do not pose a significant threat to the health of human consumers.
基金The National Basic Research Program(973 Program)of China under contract No.2014CB441502the National Natural Science Foundation of China under contract No.41876074the Cross-research Center Project by QNLM under contract No.JCZX202007。
文摘Compound-specific stable isotope analysis of individual amino acids(CSIA-AA)has been widely used in ecological and biogeochemical studies.It has been proven to be powerful in tracing the diet sources and trophic interactions.However,assessing the N sources of mesopelagic fishes has been inconclusive because the mesopelagic fishes’unique domain(water depth ranged from 0 to 1000 m)and unresolved nitrogen isotopes of various forms.This study proposes a new method for coupling instruments(ion chromatography and PreconIRMS)and chemical method of oxidation-reduction of amino acids,and also combinedδ15N of AAs withδ13C of fatty acids(FAs)to analyze the trophic interactions of mesopelagic fishes in the South China Sea(SCS).AAs were isolated by ion chromatography with high peak resolution and collected by an automated fraction collector.The chemical method then converted the AAs into N2 O with a robust oxidation yields and suitable molar ratio of NH2 OH to.Finally,theδ15N of AAs at 20 nmol were measured with a reasonable precision(<0.6‰).With this method,this study report the first batch high precisionδ15N of AAs andδ13C of FAs of mesopelagic fishes collected from SCS.Diaphus luetkeni,Chauliodus minimus and Bathygadus antrodes showed similarδ13C values of 20:4 n-6(~-28‰),while Argyropelecus affinis and Stomias had similar values(~-32‰).These results reflect that mesopelagic fishes had complex diet sources.An increase of 4‰inδ15N of glutamic acid(Glu)was found between piscivorous and planktivorous fishes,which might suggest a trophic discrimination factor of mesopelagic fishes in the SCS.This study usedδ13C of 20:4 n-6 to reveal the diet sources of mesopelagic fishes andδ15N of Glu to clarify trophic level between piscivorous and planktivorous fishes.Thus,this combinative method could therefore ultimately be applied in a variety of deep-sea ecosystem.
基金Supported by the Zhejiang Provincial Key Research and Development Program (No.2021C02047)。
文摘Accurate species identification is a key component of biodiversity research.DNA barcoding is an effective molecular method used for fish species identification.We aimed to study the DNA barcoding of fish in Zhoushan coastal waters,explore the differences and applicability of two gene fragments(12S rRNA and COI)of DNA barcoding in fish species identification,and established a comprehensive fish barcoding reference database.Two hundred and eighty-seven captured fish samples from Zhoushan coastal waters were identified using morphological characteristics and DNA barcoding.A total of 26412S rRNA sequences(belonging to eight orders,31 families,55 genera,and 66 species)and 188 COI sequences(belonging to seven orders,30 families,48 genera,and 58 species)were obtained.The lengths of the 12S rRNA sequences ranged from 165 to 178 bp,and the guanine-cytosine(GC)content was 45.37%.The average 12S rRNA interspecific and intraspecific genetic distances(K2P)were 0.10%and 26.66%,respectively.The length of the COI sequence ranged 574–655 bp,and the content of GC was 45.97%.The average 12S rRNA interspecific and intraspecific genetic distances(K2P)were 0.16%and 27.45%,respectively.The minimum interspecific genetic distances of 12S rRNA and COI(1.23%and 1.86%)were both greater than their maximum intraspecific genetic distances(2.42%and 8.66%).Three molecular analyses(NJ tree,ABGD,and GMYC)were performed to accurately identify and delineate species.Clustering errors occurred when the 12S rRNA sequences were delimited using the NJ tree method,and the delimitation results of ABGD and GMYC are consistent with the final species identification results.Our results demonstrate that DNA barcoding based on 12S rRNA and COI can be used as an effective tool for fish species identification,and 12S rRNA has good application prospects in the environmental DNA(eDNA)metabarcoding of marine fish.
文摘Analysis of stomach contents of samples of clupeid fiishes (Japanese anchovy, half-fin anchovy, zunas’ scaled sardine, rednosed glassnose and tapertail anchovy) collected from the catches of a 1982-1984 fishery resource survey showed they are zooplanktonivorous. Similar food groups, such as copepoda, Chaetognatha, Amphipoda and Mysidacea were found in the stomach. Dietary similarity coefficients were studied to evaluate the degree of similarity in the dietary species-pairs.Sea-sonal variation is discussed.