Agricultural and Biological Sciences › Aquatic Science

Fish Biology and Ecology Studies

Works Count: 104816

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Description

This cluster of papers focuses on the length-weight relationships, morphology, biodiversity, and biogeography of various fish species, with an emphasis on freshwater ecosystems. It also explores genetic diversity, conservation, and the influence of environmental factors on fish populations.

Keywords

Fish; Length-Weight Relationships; Morphology; Biodiversity; Biogeography; Freshwater; Conservation; Genetic Diversity; Phylogenetic Analysis; Environmental Factors

Inland Fishes of India and Adjacent Countries

1994-08-17

Neil B. Armantrout , P. K. Talwar , Arun G. Jhingram

This text gives a description of the 930 recognised fish species that teem the inland waters of India and adjacent countries. It provides for each species data on diagnostic features, … This text gives a description of the 930 recognised fish species that teem the inland waters of India and adjacent countries. It provides for each species data on diagnostic features, colour, size, geographic distribution, biology and abundance.

Normal Table of Xenopus Laevis (Daudin)

2020-11-13

John C. Gerhart , Marc W. Kirschner

This book is the culmination of an international collaboration of zoologists to describe the embryology of Xenopus, including the origins of the organ systems, with the purpose of promoting the … This book is the culmination of an international collaboration of zoologists to describe the embryology of Xenopus, including the origins of the organ systems, with the purpose of promoting the use of Xenopus as a model amphibian for embryological study.

Tilapiine fishes of the genera Sarotherodon, Oreochromis, and Danakilia /

1983-01-01

Ethelwynn Trewavas

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An account of the fishes found in the river Ganges and its branches /

1822-01-01

Francis Hamilton , Spencer Fullerton Baird , J. D. Swaine

Ratt 'SsMurcena.GANGETIC FISHES.Qn grows to eighteen inches or two feet in length.The under parts are of a white colour, and, where this unites with the brown of the back, the … Ratt 'SsMurcena.GANGETIC FISHES.Qn grows to eighteen inches or two feet in length.The under parts are of a white colour, and, where this unites with the brown of the back, the sides are covered with dots.The head is narrow and long, and ends in a sharp point.The mouth is very wide, and opens straight back.The jams do not protrude in opening, and are blunt and covered by lips.In the fore part of each jaw are about six long sharp teeth.In the sides of the upper jaw there are none; but in those of the under jaw there are many small ones.In the middle of the palate there are three rows.The teeth in the side rows are small and irregularly crowded; in the middle row they are placed at a distance from each other, are large, compressed, and divided into lobes.The eyes are high, large, and oblong, with circular pupils.The xosérils are double, the anterior apertures being tubular.The gill-covers are small.The membrane which ties them down is long and thick, and streaked with several fine rays, which cannot be distinctly numbered, and which leave a small crescent-shaped GANGETIC FISHES.Order II.On account of the number of fins this eel is nearly allied to the fish described by Russell, (Indian Fishes, Vol.I. No. 34,) which wants the dots on the body, and has three apertures on each side of the nose.This eel seldom exceeds a foot in length, and is less disgusting in appearance than most fishes of the kind.The under parts are white.The head is small, oval, and sharpish.The mouth is small.In each nostril there are two apertures; neither of them tubular.There are strong ¢eeth in both jaws.The eyes are small, high, and far forward.There are no gill-covers ; but a very dilatable membrane, which is striated with some slender rays, that cannot be exactly numbered, and leave a small round opening at each pectoral fin.The 6ody is not compressed.'The lateral line runs straight along the middle of the side.The vent is behind the middle.The éat/ tapers to a blunt end.The back jin is behind the middle, and contains thirty-two rays of nearly equal length.The pectoral fins are minute and rounded, and each contains eight rays.The anal fin commences near the vent, and contains fifty rays of nearly equal length.The ¢ad/ fin is rounded, and contains sixty rays.V. Genus.-Macroenatuvs.Fishes of the second order, covered with very minute scales, somewhat like a serpent, armed with prickles before the back and anal fins, and having a fin on the tail.The fishes of this genus were formerly included among the Ophidiums ; and, as the species of both were not very numerous, one genus might, perhaps, have included the whole without inconvenience.While there was only one genus, the specific names aculeatum and armatum, given to two species,The head is half oval, and flat above.The mouth is larger, and the snout shorter than in the other species.The dips are thick, with scarcely any bone; the inferior one is very blunt.In both jaws, which do not protrude in opening, are many sharp teeth, nearly equal in size, and closely imbricated.The Macrognathus .GANGETIC FISHES.29 tongue is blunt, and free from the under jaw.The palate is smooth.The nostrils are single.The eyes are far back in the middle of the head.The gill-covers are scaly.The éail is blunt.The vent is near the middle.The prickles before the back fin are about thirty-seven ; before the anal fin they are two in number.The back, tail, and anal fins can only be distinguished by the rays of the tail being a little longer than the others.Those in the back part are from eighty-three to eighty-five, those in the tail seventeen, and those in the vent part from eighty-eight to ninety.Each pectoral fin contains twenty-one divided rays.2d Species.-MacroGNnaTHUs ACULEATUS.A macrognathus with several eye-like spots on the back fin, -which is distinct from that of the tail.

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The African coelacanth genome provides insights into tetrapod evolution

2013-04-01

Chris T. Amemiya , Jessica Alföldi , Alison Lee +7 more

The discovery of a living coelacanth specimen in 1938 was remarkable, as this lineage of lobe-finned fish was thought to have become extinct 70 million years ago. The modern coelacanth … The discovery of a living coelacanth specimen in 1938 was remarkable, as this lineage of lobe-finned fish was thought to have become extinct 70 million years ago. The modern coelacanth looks remarkably similar to many of its ancient relatives, and its evolutionary proximity to our own fish ancestors provides a glimpse of the fish that first walked on land. Here we report the genome sequence of the African coelacanth, Latimeria chalumnae. Through a phylogenomic analysis, we conclude that the lungfish, and not the coelacanth, is the closest living relative of tetrapods. Coelacanth protein-coding genes are significantly more slowly evolving than those of tetrapods, unlike other genomic features. Analyses of changes in genes and regulatory elements during the vertebrate adaptation to land highlight genes involved in immunity, nitrogen excretion and the development of fins, tail, ear, eye, brain and olfaction. Functional assays of enhancers involved in the fin-to-limb transition and in the emergence of extra-embryonic tissues show the importance of the coelacanth genome as a blueprint for understanding tetrapod evolution.

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The Role of Phosphorus in the Eutrophication of Receiving Waters: A Review

1998-03-01

David L. Correll

Abstract Phosphorus (P) is an essential element for all life forms. It is a mineral nutrient. Orthophosphate is the only form of P that autotrophs can assimilate. Extracellular enzymes hydrolyze … Abstract Phosphorus (P) is an essential element for all life forms. It is a mineral nutrient. Orthophosphate is the only form of P that autotrophs can assimilate. Extracellular enzymes hydrolyze organic forms of P to phosphate. Eutrophication is the overenrichment of receiving waters with mineral nutrients. The results are excessive production of autotrophs, especially algae and cyanobacteria. This high productivity leads to high bacterial populations and high respiration rates, leading to hypoxia or anoxia in poorly mixed bottom waters and at night in surface waters during calm, warm conditions. Low dissolved oxygen causes the loss of aquatic animals and release of many materials normally bound to bottom sediments including various forms of P. This release of P reinforces the eutrophication. Excessive concentrations of P is the most common cause of eutrophication in freshwater lakes, reservoirs, streams, and headwaters of estuarine systems. In the ocean, N becomes the key mineral nutrient controlling primary production. Estuaries and continental shelf waters are a transition zone, where excessive P and N create problems. It is best to measure and regulate total P inputs to whole aquatic ecosystems, but for an easy assay it is best to measure total P concentrations, including paniculate P, in surface waters or N/P atomic ratios in phytoplankton.

Empirical relationships to estimate asymptotic length, length at first maturity and length at maximum yield per recruit in fishes, with a simple method to evaluate length frequency data

2000-04-01

Rainer Froese , C. Binohlan

Empirical relationships are presented to estimate in fishes, asymptotic length (L∞) from maximum observed length (L max ), length at first maturity (L m ) from L ∞ , life … Empirical relationships are presented to estimate in fishes, asymptotic length (L∞) from maximum observed length (L max ), length at first maturity (L m ) from L ∞ , life span (t max ) from age at first maturity (t m ), and length at maximum possible yield per recruit (L opt ) from L ∞ and from L m , respectively. The age at L opt is found to be a good indicator of generation time in fishes. A spreadsheet containing the various equations can be downloaded from the Internet at http://www.fishbase.org/download as popdynJFB.zip. A simple method is presented for evaluation of length–frequency data in their relationship to L ∞ , L m and L opt . This can be used to evaluate the quality of the length–frequency sample and the status of the population. Three examples demonstrate the usefulness of this method. 2000 The Fisheries Society of the British Isles

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Normal table of Xenopus laevis (Daudin)

1995-10-01

J. B. Gurdon

International Introductions of Inland Aquatic Species

1989-05-23

Walter R. Courtenay , R. L. Welcomme

International introductions of inland aqatic speciec , International introductions of inland aqatic speciec , مرکز فناوری اطلاعات و اطلاع رسانی کشاورزی International introductions of inland aqatic speciec , International introductions of inland aqatic speciec , مرکز فناوری اطلاعات و اطلاع رسانی کشاورزی

The selection of suitable indices for the measurement and analysis of fish condition

1989-02-01

Thomas Bolger , P. Connolly

A survey of the studies published in two leading fisheries journals revealed that the analysis and measurement of condition, based on length‐weight data, has been performed using a wide variety … A survey of the studies published in two leading fisheries journals revealed that the analysis and measurement of condition, based on length‐weight data, has been performed using a wide variety of indices and statistical procedures. Eight forms of index were identified which can be categorized into those which measure the condition of individual fish, i.e. condition factors‘, and those which measure the condition of subpopulations as a whole, i.e. regressions of log, 10 weight on log, 10 length and the parameters of such regressions. Analysis of a test data set indicated that both the form of index and properties of the data set size can dictate the patterns of condition observed. The various indices were reviewed in terms of appropriateness, simplicity and statistical correctness. It was concluded that an index should be selected only after a detailed examination of both the underlying assumptions of the index and the properties of the data set.

Behaviour of Teleost Fishes

1993-01-01

Tony J. Pitcher

A Method for Comparing the Precision of a Set of Age Determinations

1981-08-01

Richard J. Beamish , D. Fournier

An index of average percent error is a better estimate of the precision of age determinations than the conventional percent agreement method because it is not independent of the age … An index of average percent error is a better estimate of the precision of age determinations than the conventional percent agreement method because it is not independent of the age of a species.Key words: age determination, aging errors

Measuring Biological Diversity

2004-08-01

J. H. O’Keeffe

Anne E Magurran (2004) Blackwell Science Ltd, Blackwell Publishing ISBN 0-632-05633-9 www.blackwellpublishing.com Soft cover, 260 pages, £32.50 African Journal of Aquatic Science 2004, 29(2): 285–286 Anne E Magurran (2004) Blackwell Science Ltd, Blackwell Publishing ISBN 0-632-05633-9 www.blackwellpublishing.com Soft cover, 260 pages, £32.50 African Journal of Aquatic Science 2004, 29(2): 285–286

The Cichlid Fishes of the Great Lakes of Africa

1973-02-01

Rosemary H. Lowe McConnell , Geoffrey Fryer , T. D. Iles

Methods for Assessment of Fish Production in Fresh Waters

1979-02-01

J. M. Elliott , T. B. Bagenal

Methods for assessment of fish production in fresh waters , Methods for assessment of fish production in fresh waters , مرکز فناوری اطلاعات و اطلاع رسانی کشاورزی Methods for assessment of fish production in fresh waters , Methods for assessment of fish production in fresh waters , مرکز فناوری اطلاعات و اطلاع رسانی کشاورزی

Phyletic Studies of Teleostean Fishes, with a Provisional Classification of Living Forms

1967-09-01

Shelton P. Applegate , Peter Humphrey Greenwood , Donn Eric Rosen +2 more

Cube law, condition factor and weight-length relationships: history, meta-analysis and recommendations

2006-07-07

Rainer Froese

This study presents a historical review, a meta-analysis, and recommendations for users about weight–length relationships, condition factors and relative weight equations. The historical review traces the developments of the respective … This study presents a historical review, a meta-analysis, and recommendations for users about weight–length relationships, condition factors and relative weight equations. The historical review traces the developments of the respective concepts. The meta-analysis explores 3929 weight–length relationships of the type W = aLb for 1773 species of fishes. It shows that 82% of the variance in a plot of log a over b can be explained by allometric versus isometric growth patterns and by different body shapes of the respective species. Across species median b = 3.03 is significantly larger than 3.0, thus indicating a tendency towards slightly positive-allometric growth (increase in relative body thickness or plumpness) in most fishes. The expected range of 2.5 < b < 3.5 is confirmed. Mean estimates of b outside this range are often based on only one or two weight–length relationships per species. However, true cases of strong allometric growth do exist and three examples are given. Within species, a plot of log a vs b can be used to detect outliers in weight–length relationships. An equation to calculate mean condition factors from weight–length relationships is given as Kmean = 100aLb−3. Relative weight Wrm = 100W/(amLbm) can be used for comparing the condition of individuals across populations, where am is the geometric mean of a and bm is the mean of b across all available weight–length relationships for a given species. Twelve recommendations for proper use and presentation of weight–length relationships, condition factors and relative weight are given.

Anaesthetic and Sedative Techniques for Aquatic Animals

2008-05-16

Introduction Stress in aquatic animals The nature of anaesthesia, sedation and analgesia The features of anaesthetic agents and their legal use Factors affecting the response of aquatic ectotherms to anaesthesia … Introduction Stress in aquatic animals The nature of anaesthesia, sedation and analgesia The features of anaesthetic agents and their legal use Factors affecting the response of aquatic ectotherms to anaesthesia Anaesthesia of aquatic invertebrates Anaesthesia of fish I: Inhalation anaesthesia Anaesthesia of fish II: Inhalation anaesthesia using gases Anaesthesia of fish III: Parenteral and oral anaesthesia Anaesthesia of fish IV: Non-chemical methods Anaesthesia of amphibians and reptiles Transportation and anaesthesia Concluding remarks Glossary of nomenclature and structure of anaesthetic drugs Glossary of technical terms Index

Fish and Fisheries of India

1977-03-16

Carl L. Hubbs , V. G. Jhinqran

The genomic substrate for adaptive radiation in African cichlid fish

2014-09-01

David Brawand , Catherine E. Wagner , Yang Li +7 more

Cichlid fishes are famous for large, diverse and replicated adaptive radiations in the Great Lakes of East Africa. To understand the molecular mechanisms underlying cichlid phenotypic diversity, we sequenced the … Cichlid fishes are famous for large, diverse and replicated adaptive radiations in the Great Lakes of East Africa. To understand the molecular mechanisms underlying cichlid phenotypic diversity, we sequenced the genomes and transcriptomes of five lineages of African cichlids: the Nile tilapia (Oreochromis niloticus), an ancestral lineage with low diversity; and four members of the East African lineage: Neolamprologus brichardi/pulcher (older radiation, Lake Tanganyika), Metriaclima zebra (recent radiation, Lake Malawi), Pundamilia nyererei (very recent radiation, Lake Victoria), and Astatotilapia burtoni (riverine species around Lake Tanganyika). We found an excess of gene duplications in the East African lineage compared to tilapia and other teleosts, an abundance of non-coding element divergence, accelerated coding sequence evolution, expression divergence associated with transposable element insertions, and regulation by novel microRNAs. In addition, we analysed sequence data from sixty individuals representing six closely related species from Lake Victoria, and show genome-wide diversifying selection on coding and regulatory variants, some of which were recruited from ancient polymorphisms. We conclude that a number of molecular mechanisms shaped East African cichlid genomes, and that amassing of standing variation during periods of relaxed purifying selection may have been important in facilitating subsequent evolutionary diversification. Genomes and transcriptomes of five distinct lineages of African cichlids, a textbook example of adaptive radiation, have been sequenced and analysed to reveal that many types of molecular changes contributed to rapid evolution, and that standing variation accumulated during periods of relaxed selection may have primed subsequent diversification. The 2,000 or so species of cichlid fish, to be found in the lakes and rivers of Africa's Rift Valley, provide the classic example of adaptive radiations. This large-scale international collaboration has sequenced and analysed the genomes and transcriptomes of five distinct lineages of African cichlids. The data reveal an excess of gene duplications in comparison to other fish species. There is an abundance of non-coding element divergence; accelerated coding sequence evolution; expression divergence associated with transposable element insertions in orthologous gene pairs; and regulation by novel miRNAs. Sequencing data from sixty individuals from six closely related Lake Victoria species point to rapid cichlid speciation associated with genome-wide diversifying selection on coding and regulatory variants, and imply that ancient periods of relaxed purifying selection enabled the accumulation of standing variation, which may have been important in facilitating diversification.

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The Biology of Euphausiids

1969-01-01

J. Mauchline , Len Fisher

Advances in fish science and technology

1981-01-01

Geoffrey Leighton Kesteven

Biological Basis of Freshwater Fish Production

1968-07-01

Reneat M. Darnell

Fishes of the North-eastern Atlantic and the Mediterranean

1987-11-01

N. Daan

Fishes: An Introduction to Ichthyology

1996-12-27

Hayden T. Mattingly , Peter B. Moyle , Joseph J. Cech +1 more

The Evolutionary Biology of the Threespine Stickleback

1995-05-01

John D. Reynolds , Michael A. Bell , Susan A. Foster

The Removal Method of Population Estimation

1958-01-01

Calvin Zippin

A biweekly posttreatment fish census was taken along a 5,600-foot ditch traversing the marsh; enumerations and estimates of the numbers of each species encountered were supplemented by sampling collections. The … A biweekly posttreatment fish census was taken along a 5,600-foot ditch traversing the marsh; enumerations and estimates of the numbers of each species encountered were supplemented by sampling collections. The census was abandoned when progress in repopulation ended its dependability. Repopulation by fishes began slowly about 4 weeks after the kill, was undeniable at 6 weeks, considerable by 8, and climactic at 10. It was initiated by the broad killifish (Cyprinodon v. variegatus), the dominant invader, and included record minimumsized tarpon by the seventeenth week, but large-sized fish of such species as snook were absent, perhaps significantly. The general absence of dead and dying fishes and the scarcity of living fishes in the marsh after 2 weeks and later suggests that much of the fish population commuting between the marsh and adjacent inshore shallows of Indian River was destroyed. LITERATURE CITED

Ontogeny and Systematics of Fishes

1985-05-03

Clark Hubbs , H.-G. Moser , William J. Richards +4 more

Treatise on Invertebrate Paleontology

1950-10-01

Raymond C. Moore

Treatise on invertebrate paleontology , Treatise on invertebrate paleontology , مرکز فناوری اطلاعات و اطلاع رسانی کشاورزی Treatise on invertebrate paleontology , Treatise on invertebrate paleontology , مرکز فناوری اطلاعات و اطلاع رسانی کشاورزی

Ecology of freshwater fish production

1979-07-01

Colin E. Nash

Water quality management for pond fish culture

1983-01-01

Michael B. New

The Evolutionary Biology of the Threespine Stickleback

1994-03-31

Abstract The threespine stickleback is a small fish of temperate coastal and fresh waters that exhibits extraordinary phenotypic diversity. Benefiting from its amenability to observation in the field and manipulation … Abstract The threespine stickleback is a small fish of temperate coastal and fresh waters that exhibits extraordinary phenotypic diversity. Benefiting from its amenability to observation in the field and manipulation in the laboratory, Niko Tinbergen pioneered the threespine stickleback’s use in behavioral studies and established it as a model system in ethology. This up-to-date volume incorporates reviews from active researchers who use studies of the fish to address a broad variety of evolutionary issues, including optimal foraging, armor variation, speciation, and the endocrine basis for correlated behavioral characters. The work demonstrates the value of viewing the biology of a single organism simultaneously from multiple perspectives. Students and researchers in ecology, evolution, animal behavior, and vertebrate zoology will find much of interest in this useful book.

Fishes of Japan : with pictorial keys to the species

2002-01-01

徹次中坊

Population Dynamics of Senilia senilis (Linnaeus, 1758) from the Senegal River Delta, Senegal

2025-06-25

Mag Maguette . Auteur du texte Diop , Alioune Faye , Malick Diouf | American journal of water resources

A new super narrow-ranged endemic Phoxinus minnow (Leuciscidae) from the Caucasus

2025-06-25

Oleg Artaev , И. С. Турбанов , A. A. Bolotovskiy +2 more | Zoosystematics and Evolution

A new species, Phoxinus ayukensis sp. nov. , from the Kuban basin (Northwestern Caucasus) is described. This species has an extremely narrow range of approximately 5–7 km in a seasonally … A new species, Phoxinus ayukensis sp. nov. , from the Kuban basin (Northwestern Caucasus) is described. This species has an extremely narrow range of approximately 5–7 km in a seasonally almost drying stream within the karstic region. The new species has a moderate genetic distance in cytochrome b mtDNA ( p -distance = 0.026 ± 0.005) from geographically and genetically close species in the Kuban basin— P. adagumicus —and differs from all known Phoxinus species by a highly increased number of scales in the lateral series: 87–105 (mean 97.7), differs from other species from Eastern Europe and the Caucasus ( P. adagumicus , P. chrysoprasius , P. colchicus , and P. isetensis ) by an increased frequency of occurrence of seven rays in the pelvic fin (ca. 35%) and an increased number of scales between bases of dorsal and anal fins (32–41, mean 36.7). Morphologically, the new species is the most different from the other Caucasian species, but it is closer to the Northern minnow P. isetensis ; that might be explained by phenotypic convergence caused by adaptation to cold waters. The range of the new species is limited by waterfalls in the upper reach of the Ayuk Stream, where subterranean water outlets probably contributed to its survival. The role of Pleistocene glaciations in shaping the modern distribution and environmental differences in evolutionary divergence of Caucasian Phoxinus is highlighted. Low genetic diversity coupled with extremely limited range within the seasonally half-drying stream suggests a high rank of protection for new species.

Ficha de Myliobatis freminvillei

2025-06-24

Otto Bismarck Fazzano Gadig , Carolus Maria Vooren , Francisco Marcante Santana da Silva +7 more | Datasets - Sistema SALVE - ICMBio

A taxonomic review of Bagarius catfish (Siluriformes, Sisoridae) in the Salween and Irrawaddy rivers, with descriptions of two new species from China and Myanmar

2025-06-24

Yu Zeng , Xin-Rui Pu , Hao-Tian Lei +2 more | Zoosystematics and Evolution

The genus Bagarius is a group of large, benthic, predatory catfishes found in South and Southeast Asia. Two new species of Bagarius , B. protos Zeng & Chen, sp. nov. … The genus Bagarius is a group of large, benthic, predatory catfishes found in South and Southeast Asia. Two new species of Bagarius , B. protos Zeng & Chen, sp. nov. , and B. dolichonema Zeng & Chen, sp. nov. , are described from the Salween River Basin, Yunnan Province, China, and Irrawaddy River Basin, Myanmar, respectively. Bagarius protos and B. dolichonema both differ from B. vegrandis and B. suchus in their large size and the adipose-fin origin being nearly vertical to the anal-fin origin. Bagarius protos most closely resembles B. lica and B. rutilus in overall morphology but can be distinguished from B. lica by the absence of the brow ridge formed by the lateral margin of the frontal and from B. rutilus by the dark yellow (instead of orange) coloration of the fins in life. It further differs from two other congeners in its short filamentous extensions of the pectoral-fin spine. Bagarius dolichonema is morphologically and genetically most similar to B. bagarius ; it can be distinguished from B. bagarius by strong dorsal spines slightly flattened immediately anterior to the adipose fin, distally slender neural spines of the 4 th –6 th vertebrae, and shorter filamentous extensions of the pectoral-fin spine. This new species further differs from three other congeners by its longer filamentous extensions of the pectoral-fin spine and weak notches in the anterodorsal margin of the first dorsal pterygiophores. Molecular phylogeny based on the cytochrome c oxidase subunit I (COI) gene also confirms the validity of these two new species. The estimated K2P genetic distances between B. protos and congenerics range from 8.0% to 12.6%, and between B. dolichonema and congenerics range from 5.7% to 12.1%.

Livelihood Analysis of Magur (Clarias batrachus) Fish Farmers in Kalindi Village of Purba Medinipur District, West Bengal, India

2025-06-23

Abhishek Giri , Shriparna Saxena | Journal of Experimental Agriculture International

Aims: To assess the socio-economic characteristics, motivations, and training levels of rural households engaged in Magur (Clarias batrachus) seed production using low-cost hatchery systems, and to examine the relationship between … Aims: To assess the socio-economic characteristics, motivations, and training levels of rural households engaged in Magur (Clarias batrachus) seed production using low-cost hatchery systems, and to examine the relationship between demographic variables and enterprise orientation. Study Design: Descriptive cross-sectional study using structured surveys and statistical analysis. Place and Duration of Study: Kalindi Village, Purba Medinipur district, West Bengal, India, conducted during the years 2022–2024. Methodology: A purposive survey was conducted among 244 smallholder farmers involved in Magur seed production using low-cost hatchery infrastructure. Data were collected via structured interviews, field observation, and questionnaires covering demographics, education, aquaculture experience, training, and enterprise motivation. Cross-tabulations and chi-square tests were used to analyze relationships among variables such as age, education, family size, and enterprise aim. Results: Among the 244 respondents, 98.4% were male and 43.8% were graduates or higher. While 56.92% had 10–20 years of experience, only 23.1% received formal hatchery training. A vast majority (93.03%) were engaged in seed production to meet household needs, and only 6.97% cited profit maximization. Chi-square analysis showed no significant association between family size or education level and enterprise aim (p = 0.301 and p = 0.274 respectively), but a highly significant association with age group (p < 0.0001), indicating that younger farmers were more commercially motivated. Conclusion: Low-cost hatchery systems provide important livelihood support in rural aquaculture but are predominantly subsistence-oriented. Young, educated farmers show greater commercial interest. Promoting targeted training, market linkages, and inclusive policies could help transform these ventures into sustainable aquaculture enterprises.

Meta-analysis of Growth Characteristics of Deep-Sea Fishes from the Indian Waters: A Conservation Perspective

2025-06-23

N. K. Suyani , A. Kathirvelpandian , T. T. Ajith Kumar +1 more | Thalassas An International Journal of Marine Sciences

Fishery, Growth and Reproductive Biology of Metapenaeus affinis (Decapoda, Penaeidae) in the Iraqi waters

2025-06-23

Abdul-Razak M. Mohamed , Khelud A. Hassan , Jassim M. Abed | International Journal of Environmental Engineering and Development

The study evaluated the fishery, growth and reproductive biology of the Jinga shrimp (Metapenaeus affinis) in Iraqi waters from November 2022 to October 2023. The monthly shrimp landings from Iraqi … The study evaluated the fishery, growth and reproductive biology of the Jinga shrimp (Metapenaeus affinis) in Iraqi waters from November 2022 to October 2023. The monthly shrimp landings from Iraqi marine waters ranged from 57 tons in December 2022 to 407 tons in September 2023, with an annual value of 3,515 tons. 8,021 individuals of M. affinis, ranging from 2.0 to 15.6 cm, were collected from the East Hammar marsh and Iraqi marine waters. The length-weight relationship indicated that males and females exhibited negative allometric growth patterns, with a significant difference between them. The mean values of the relative condition factor were 0.98±0.037 and 1.02±0.043 for males and females, respectively, referring to the healthy condition for both sexes. The growth model for the species was Lt= 16.3 (1- exp (-0.92 (t+0.084))). The overall sex ratio (male: female) was 1:1.41. The length at first maturity (Lm50) was 8.2 cm. The gonadosomatic index (GSI) values fluctuated from 2.14% in June to 4.34% in April for females of M. affinis. These results can assist in fisheries management and conservation of the shrimp species in Iraqi waters.

Comparative Analysis Of Biochemical Constituents In Labeo Rohita (Ham.) From Normal And Alkaline Soil Ponds

2025-06-23

P. N. Dwivedi , Prerna Dhyani , Sharad Pandey +3 more | Journal of Neonatal Surgery

The present study investigates the age-related variations in the biochemical composition of Labeo rohita (Hamilton) under contrasting soil pH conditions. Conducted at the Department of Fisheries and Agricultural Biochemistry, Narendra … The present study investigates the age-related variations in the biochemical composition of Labeo rohita (Hamilton) under contrasting soil pH conditions. Conducted at the Department of Fisheries and Agricultural Biochemistry, Narendra Deva University of Agriculture and Technology, Narendra Nagar (Kumarganj), Faizabad, Uttar Pradesh, the research focuses on fish from a 5-year-old pond with normal soil (pH 7.0) and a newly constructed pond with alkaline soil (pH 9.5). Fish specimens were categorized into four age groups: 6, 18, 36, and 60 months, with age determination following the methodology of Johal and Tandon (1996). Biochemical analyses were performed on muscle tissue to assess moisture, fat, protein, and carbohydrate content. A Complete Randomized Design (CRD) was employed to evaluate the significance of age and soil pH on these parameters. Preliminary findings suggest that both age and environmental factors, such as soil pH, influence the biochemical composition of Labeo rohita. These insights are crucial for optimizing aquaculture practices and enhancing the nutritional quality of fish.

Assessment of reproductive biology of Garra langlungensis (Teleostei: Cyprinidae) from the Langlung River, Nagaland, India

2025-06-21

Sophiya Ezung , Pranay Punj Pankaj | Journal of Fisheries

The stone sucker, Garra langlungensis Ezung, Shaingningam & Pankaj, 2021, is confined to the Langlung River, near Zutovi village in Dimapur district of Nagaland, India. This endemic fish is a … The stone sucker, Garra langlungensis Ezung, Shaingningam & Pankaj, 2021, is confined to the Langlung River, near Zutovi village in Dimapur district of Nagaland, India. This endemic fish is a common food item among the local people. There is scarce information available on this species. Despite its rising exploitation, the lack of data could contribute to its decline and potential loss. The present study involved analysis of 213 specimens from the Langlung River, collected monthly over a period of one year, to determine the sex ratio, gonadosomatic Index (GSI), and fecundity. The sex ratio of males to females was 1:0.43 (deviation from the expected 1:1 ratio), showing a male-dominated population. The monthly assessment of GSI indicated that G. langlungensis breed once a year, with maximum GSI values of 8.1 (male) and 11.5 (female) in April and a short breeding season extending from February to May. Fecundity, based on data from 16 mature fish specimens, was the highest (844 eggs) in 77.9 mm TL (0.56 g) and the lowest (319 eggs) in 55.2 mm TL specimen (0.23 g). A significant correlation between fecundity and ovary weight (r = 0.915) was recorded. This study provides insights into the sex ratio, GSI, and fecundity of G. langlungensis, which facilitate the identification of fish stocks in their natural habitats and the development of appropriate conservation measures.

A Look at the Deadly Shark Attack on an Israeli Diver off the Mediterranean Coast of Hadera, Palestine

2025-06-21

Abdel Fattah N. Abd Rabou , Maha F. Gafar , Aliaa M. Mohanna +7 more | UTTAR PRADESH JOURNAL OF ZOOLOGY

The Mediterranean Sea is home to a considerable number of shark species, some of which have posed a threat to humans. The hot waters discharged from the Hadera (Orot Rabin) … The Mediterranean Sea is home to a considerable number of shark species, some of which have posed a threat to humans. The hot waters discharged from the Hadera (Orot Rabin) power plant in northwestern Palestine attract schools of two large coastal shark species: Dusky Sharks (Carcharhinus obscurus Lesueur, 1818) and Sandbar Sharks (Carcharhinus plumbeus Nardo, 1827) every year from November to May. On Monday, April 21, 2025, a 45-year-old Israeli diver was fatally attacked by sharks off the Mediterranean coast of Hadera. The present descriptive study aims to shed light on this rare deadly incident. The study relied on collecting the necessary data through monitoring websites, news, and social media platforms. The Mediterranean coast of Hadera is characterized by a fascinating phenomenon that attracts many beachgoers, as they approach the shallow and warm waters dominated by predatory sharks. Several possible reasons for the shark attack on the Israeli diver have been listed, including the diver's attempt to feed the shark dead fish for filming, the smell of bleeding fish the diver may have been carrying on his belt, mistaken identity of the sharks, the shark's ability to detect the diver's subtle electrical impulses, the diver's possible sudden movements, loud noises, and frantic swimming that attracted the sharks, behavioral changes in the sharks due to human harassment, curiosity and confusion of the shark, hunger and starvation the sharks may have been suffering from, etc. The incident received unprecedented media coverage locally, regionally, and internationally, and sparked widespread interaction on social media platforms. Many Arab posts praised the shark for carrying out the attack, amid the fierce, destructive, and bloody war Israel has been waging against the Gazans since October 7, 2023. To prevent this incident from happening again, there is a need to manage the Mediterranean coast of Hadera in a way that is safe for humans and sharks.

Breeding and Ontogeny of the Aquarium-Traded Scissortail Rasbora (Rasbora trilineata)

2025-06-20

Krittima Kasamawut , Suriya Udduang , Supalug Kattakdad +4 more | Animals

Fishes of the genus Rasbora in the Cyprinidae family comprise 88 species [...] Fishes of the genus Rasbora in the Cyprinidae family comprise 88 species [...]

SEAWEED (Gracilaria sp.) AS A PHYTOREMEDIAN FOR WASTE WATER FROM INTENSIVE PONDS FOR VANAMEI SHRIMP (Litopenaeus vannamei) IN LUWU REGENCY

2025-06-20

Patahiruddin Patahiruddin , Andi Mi’rajusysyakur Muchlis , Siswati Siswati +2 more | Jurnal Perikanan Unram

Sanitasi lingkungan perairan tambak udang vanamei (Litopenaeus vannamei) akan meningkatkan pertumbuhan udang dan peningkatan ekonomi. Kendala dalam budidaya perairan adalah menurunnya kualitas hasil produksi dan penurunan kualitas air. Dibutuhkan biofilter … Sanitasi lingkungan perairan tambak udang vanamei (Litopenaeus vannamei) akan meningkatkan pertumbuhan udang dan peningkatan ekonomi. Kendala dalam budidaya perairan adalah menurunnya kualitas hasil produksi dan penurunan kualitas air. Dibutuhkan biofilter sebagai fitoremidiasi untuk mengurangi kandungan amoniak yang tinggi dari sisa pakan dan feses. Komponen utama dari teknologi ini adalah rumput laut (Gracilaria sp.) sebagai teknologi hidup yang memberikan layanan dalam mengatasi permasalahan lingkungan. Oleh karena itu, teknologi fitoremediasi dapat digunakan untuk mengelola dinamika unsur hara dan air; Hal ini dapat menghasilkan peningkatan kualitas air yang signifikan serta pemulihan ekosistem yang terdegradasi. Tujuan penelitian adalah untuk mengetahui pengaruh perbedaan kepadatan Gracilaria sp. sebagai fitoremedian dalam sistem budidaya terhadap penurunan kandungan amonia (NH3) limbah air tambak udang di Batu Lotong, Kecamatan Larompong Selatan, Kabupaten Luwu, Sulawesi Selatan. Penelitian Menggunakan Rancangan Acak Lengkap (RAL) dengan 4 perlakuan 3 kali pengulangan. Hasil pengukuran pada percobaan menunjukkan bahwa kandungan amonia (NH3) tertinggi pada perlakuan D (0 g rumput laut) berkisar 0,0074 mg/L - 0,0335 mg/L dan terendah pada perlakuan A (100 g rumput laut) berkisar 0,0032 mg/L-0,0335 mg/L. Laju pertumbuhan spesifik bobot harian rumput laut Gracilaria sp. pada perlakuan A (2,95) % per hari, B (2,59 %) per hari, C (1,81 %) per hari, dan D (0 %) kontrol / tidak diberi rumput laut. Hal ini menunjukkan bahwa perbedaan pemberian kepadatan rumput laut Gracilaria sp. sebagai fitoremedian pada sistem budidaya berpengaruh terhadap penurunan kandungan amonia (NH3) dan laju pertumbuhan spesifik harian rumput laut Gracilaria sp.

Impact of Tetrapleura tetraptera aqueous extract on water quality variables and hatching success of Clarias gariepinus

2025-06-20

I.E. Asuquo , Chukwuma Okereke Ofor | Journal of Aquatic Sciences

The use of ichthyotoxic plants to stupefy fishes is a common fishery practice in tropical regions despite the superiority of modern netting materials and prohibition by law. Though these plants … The use of ichthyotoxic plants to stupefy fishes is a common fishery practice in tropical regions despite the superiority of modern netting materials and prohibition by law. Though these plants derivatives are believed to be nontoxic compared to their synthetic counterparts, they may contain a number of harmful ingredients or their secondary metabolites may have deleterious side effects. This study investigated the physico-chemical parameters of water media exposed to varying concentrations of Aidan, Tetrapleura tetraptera aqueous extract and their implications for the hatching success of Clarias gariepinus. Mature leaves of T. tetraptera were harvested, verified, crushed, and soaked in 6 liters of borehole water to obtain the stock solution. Serial dilutions were prepared from this solution into six treatments with the following concentrations: 75, 50, 25, 12.5, 6.25, and 3.125 ml/l designated as T1 to T6 respectively. The seventh treatment served as the control (without extract). Fertilized egg masses of C. gariepinus were exposed to the different concentrations of the aqueous extract in 15-liter plastic containers for 96 hours, during which period observations were made. Hatching success and water quality variables were determined according to standard procedures. The study revealed significant alterations in physico-chemical parameters, including dissolved oxygen (3.27 mg/l), pH (4.07), conductivity (63.11uS/cm), total dissolved solids (32.1 mg/l), and biochemical oxygen demand (0.67 mg/l) across treatment groups. A dose-dependent effect of T. tetraptera on hatching success was observed, with higher concentrations (T1 and T2) leading to decreased hatching rates. The T6 group exhibited the highest hatching success of 90%, while other treatment groups showed significantly (p<0.05) lower rates, with the highest concentration (75ml/l) resulting in only 10% hatching success. The findings of the present study underscore the potential risks associated with the use of T. tetraptera in capture fisheries. It also highlighted the need for strategic management of plant extracts to ensure the health and viability of fish populations and aquatic ecosystems.

Karyotype Macrostructure in Two Species of Cobitis from Türkiye: A First Report for Cobitis battalgilae and a Re-examination of Cobitis turcica (Cypriniformes: Cobitidae)

2025-06-20

Atilla Arslan , Zafer Alpaslan | Acta Zoologica Bulgarica

Türkiye has a remarkable geography with its rich inland water ichthyofauna, where many endemic species are found, the genus Cobitis stands out as an important biodiversity element. This genus includes … Türkiye has a remarkable geography with its rich inland water ichthyofauna, where many endemic species are found, the genus Cobitis stands out as an important biodiversity element. This genus includes a group of loaches distributed in Europe, Asia and parts of North Africa, usually living in freshwater environments. There are 22 endemic species of Cobitis in Türkiye, distributed in Central, Western and South-Eastern Anatolia. The chromosomal characteristics of C. battalgilae have not been studied, limiting the scope of biological and ecological studies. We employed Giemsa-, C-, and Ag-NOR staining to characterise the karyotype macrostructure of two species of Cobitis from Türkiye, reporting cytogenetic data for the first time in C. battalgilae and reassessing previously known features of C. turcica. The diploid chromosome number in C. battalgilae and C. turcica was 2n = 50 and similar karyotype structures (8 m + 16 sm + 14 st + 12 a; NF = 74) were observed. In both species, there was a secondary constriction on the short arm of autosomal pair 1. Heteromorphic sex chromosomes were not detected. Constitutive heterochromatin (C-bands) was located in the peri/centromeric regions and differed in intensity on some chromosomes. Active Ag-NORs were detected on both homologues and were associated with heterochromatin on the largest metacentric chromosome pair (no. 1) in both species The cytogenetic findings of these two species supported the close relatedness revealed by phylogenetic analysis based on molecular (mitochondrial genes) data.

Jenis Bentos Dan Plankton Pada Sungai Jemile Kabupaten Muara Enim Provinsi Sumatera Selatan

2025-06-20

Putri Anggraini , Eva Suryani , Rita Puspasari +2 more | Environmental Science Journal (esjo) Jurnal Ilmu Lingkungan

Rivers are vital freshwater ecosystems that play an essential role in maintaining environmental balance and supporting aquatic life. The benthic and planktonic communities serve as bioindicators of water quality and … Rivers are vital freshwater ecosystems that play an essential role in maintaining environmental balance and supporting aquatic life. The benthic and planktonic communities serve as bioindicators of water quality and form integral components of the aquatic food web. This study aims to analyze the structure of benthos and plankton communities in the Jemile River, Muara Enim Regency, South Sumatra, and to evaluate their relationship with water quality parameters. The findings revealed the presence of Baetidae larvae, indicating clean and well-oxygenated waters, alongside Chironomidae, which tolerate organically enriched substrates. Among plankton, Brachionus was found as an indicator of eutrophic conditions, and Gyrosigma served as a primary producer. The diversity of organisms observed suggests habitat quality variations influenced by domestic, agricultural, and mining activities around the river. This study highlights the complex ecological dynamics of the Jemile River and underscores the need for continuous monitoring to support sustainable water resource management.

A New Species of the Genus Pethia (Teleostei: Cyprinidae) from the Brahmaputra Drainage, India

2025-06-20

Niti Sharma , Waikhom Vishwanath , MAYANGLAMBAM DISHMA +2 more | National Academy Science Letters

Stock Assessment of Long Whisker Catfish (Mystus gulio): Ensuring the Fisheries’ Sustainability in the Sundarbans Mangrove, Bangladesh

2025-06-20

Md. Tanvir Rahman Ovi , T. K. Sarkar , Dwipika Gope +6 more | Fishes

The world’s largest mangrove, Sundarbans, Bangladesh, is the habitat of the euryhaline catfish Nona Tengra (Mystus gulio). This study aimed to assess the stock status of M. gulio and provide … The world’s largest mangrove, Sundarbans, Bangladesh, is the habitat of the euryhaline catfish Nona Tengra (Mystus gulio). This study aimed to assess the stock status of M. gulio and provide reference points for sustainable fisheries’ management. One-year length–frequency (LF) data were collected from the Sundarbans region of Bangladesh and analyzed using the Length-Based Bayesian Biomass (LBB) method and the Length-Based Spawning Potential Ratio (LBSPR) model. The findings showed healthy biomass (B/BMSY = 1.2), with 57% of the wild stock of this species being harvested (B/B0 = 0.43). The calculated fishing mortality ratio indicated the underfishing conditions (F/M = 0.9). Safe exploitation (E = 0.46) was depicted, as E was smaller than the permitted level of 0.5. The value of capture length (Lc = 12.8 cm) was larger than the optimum capture length (Lc_opt = 10.0 cm) and the optimum length for maximum yield per recruit (Lopt = 12.0 cm) and larger than the maturity length (Lm = 9.16 cm), indicating the capture of mature individuals. The calculated Spawning Potential Ratio (SPR = 48%) was higher than the target reference points (SPR = 40%). This research evaluated the sustainable stock status. Although the margin between Lc_opt and Lm is very narrow, setting the minimum capture size at Lopt would be a conservative buffer to ensure long-term sustainability. The recommended minimum harvest size is 12 cm for M. gulio. Current fishing gear selectivity can ensure the sustainability of M. gulio in Sundarbans, Bangladesh; however, maintaining current fishing practice through careful management is suggested. Further assessments with length-based and other low-data methods should be conducted to refine exploitation estimates and trends.

Integrative taxonomy describes a new species of the genus Sinocyclocheilus (Cypriniformes, Cyprinidae) from the Beipanjiang River, Guizhou Province, southwest China

2025-06-20

Zhi-Xia Chen , Tao Luo , Zeng Qi Zhao +3 more | Zoosystematics and Evolution

We describe a new species, Sinocyclocheilus panzhouensis sp. nov. , from Panzhou City, Guizhou Province, China, using morphological and genetic evidence. Phylogenetic analysis of mitochondrial cytochrome b (Cyt b ) … We describe a new species, Sinocyclocheilus panzhouensis sp. nov. , from Panzhou City, Guizhou Province, China, using morphological and genetic evidence. Phylogenetic analysis of mitochondrial cytochrome b (Cyt b ) and NADH dehydrogenase subunit 4 (ND4) sequences reveals distinct genetic divergence from related species, with genetic distances ranging from 1.7–14.2% in Cyt b and 1.2–12.6% in ND4. Morphologically, S. panzhouensis sp. nov. is characterised by absence of a horn-like structure and indistinct elevation at the head-dorsal junction; body covered with tiny scales, with irregular black markings; wide mouth, 7.8–9.3% of standard length and longer pectoral fin 17.9–30.6% of standard length; last unbranched ray of dorsal-fin with weak serrations along posterior margin; tip of pectoral fins not reaching the pelvic-fin origin; lateral line complete and curved, with pores 71–79; and eight rakers on the first gill arch. This discovery raises the number of Sinocyclocheilus species in Guizhou to 19, with five species found in the Beipanjiang River. This study highlights the need for further surveys in Guizhou to explore the full species diversity of the genus.

Hematological and Histological Effects of Heavy Metals on Fish (Channa punctatus) of Gomati River, Lucknow

2025-06-20

Bharti Gupta , Ramakant Maurya , Pradip Kumar Saini +1 more | Agricultural Science Digest - A Research Journal

Background: Sediment deposition and accumulation expose sediment-dwelling aquatic animals to lead. Heavy metals regulation is urgent and nanotoxicology data is essential for risk assessment. Heavy metal products will likely impact … Background: Sediment deposition and accumulation expose sediment-dwelling aquatic animals to lead. Heavy metals regulation is urgent and nanotoxicology data is essential for risk assessment. Heavy metal products will likely impact the food and feed industry. Classifying essential, non-essential and toxic elements. Methods: Channa punctatus fish from Lucknow, India, were tested for toxicity. Water samples were taken after acclimation, feeding and fasting. Spectrophotometers measured heavy metals. Result: Our experiment shows lead toxicity in Channa punctatus fish, causing haematological changes, organ abnormalities, oxidative stress, antioxidant suppression and increased lipid peroxidation.

THE PSEUDOBRANCH DEVELOPMENT IN EASTERN MOSQUITO FISH GAMBUSIA HOLBROOKI, GIRARD 1859 (CYPRINODONTIFORMES, POECILIIDAE) FROM JADIRIYAH LAKE, BAGHDAD, IRAQ

2025-06-19

Khloud AL-Lehaibe , Entekhab AL-Shuwaili , Ahmed K. Mahdi | Bulletin of The Iraq Natural History Museum

The aim of the current investigation is to study the embryogenesis of the pseudobranchia (PB) in the Eastern mosquito fish Gambusia holbrooki, Girard, 1859 (Cyprinodontiformes, Poeciliidae). Histological sections from 2-4 … The aim of the current investigation is to study the embryogenesis of the pseudobranchia (PB) in the Eastern mosquito fish Gambusia holbrooki, Girard, 1859 (Cyprinodontiformes, Poeciliidae). Histological sections from 2-4 mm long embryos revealed the presumable PB as a cell mass surrounded by a row of squamous cells in the operculum, as well as the formation of cartilage and blood vessels, and the beginning of the formation of its lamellae. In 5-7.75 mm long embryos, a prominent rise appeared in the mass of cells and PB lamellae, along with an increase in melanin deposition around the blood vessels. Moreover, a row of squamous cells encircled the rise from the front and back. At this stage, the parallel arrangement of the cartilage-attached lamellae correlated with increased melanin concentration around the blood vessels. In newborns, the differentiated cells increased similar to that appearing in the adult’s stages.

Biological and genetic structure of Epinephelus costae (Steindachner, 1878) population in Iskenderun Bay, eastern Mediterranean Sea

2025-06-19

Servet Ahmet Doğdu | PeerJ

This study aimed to status of the Iskenderun population of Epinephelus costae, an important fish species in the Mediterranean Sea ecosystem, by providing detailed data on its genetic structure using … This study aimed to status of the Iskenderun population of Epinephelus costae, an important fish species in the Mediterranean Sea ecosystem, by providing detailed data on its genetic structure using mtDNA COI gene region and biological parameters as length-weight relationship, age-growth characteristics, von Bertalanffy growth parameters. A total of 325 specimens were studied from Iskenderun Bay in the eastern Mediterranean (Türkiye), ranging in length from 16.7 to 43.5 cm. For genetic studies using the mtDNA COI gene region, 30 samples were selected from different size groups representing the population. Age 2 represented the majority of the population (31.69%). The value of "b" of the length-weight relationship was higher than "3" (3.0839). The results for the von Bertalanffy growth parameters were observed as L α = 125.8 cm; k = 0.0570 year -1; t 0 = - 2.2410 year. Fulton's condition factor was observed as 1.4120. The growth performance index was calculated as 4.35. The genetic diversity of the population was found to be 0.0332 ± 0.0028. Sixteen haplotypes were observed in the population and haplotype diversity was calculated as 0.9379. Tajima's neutrality test (-0.9437), Fu's Fs Statistic (-0.0340), Strobeck's S Statistic (0.6620), Achaz's Y test (-1.8728), Fu and Li D (1.1570) and F Test (0.4444) were applied to test whether the population is in balance. In conclusion, the biological and genetic analyses carried out within the scope of our study revealed that the Iskenderun population of E. costae is in stable condition.

Đánh giá khả năng chọn lọc theo mắt lưới hình thoi của nghề lưới đáy tại Cà Mau

2025-06-18

Nghiệp Vũ Kế , Lương Nguyễn Trọng | Tạp chí Khoa học - Công nghệ Thủy Sản Trường Đại học Nha Trang

Nghiên cứu đã sử dụng 3 mẫu lưới có kích thước mắt lưới ở đụt lần lượt là 18 mm, 20 mm, 24 mm và lưới đụt ngoài với kích … Nghiên cứu đã sử dụng 3 mẫu lưới có kích thước mắt lưới ở đụt lần lượt là 18 mm, 20 mm, 24 mm và lưới đụt ngoài với kích thước mắt lưới 04 mm tổ chức đánh bắt thử nghiệm 30 mẻ lưới tại vùng biển huyện Ngọc Hiển, tỉnh Cà Mau để thu thập dữ liệu. Quá trình đánh bắt thử nghiệm đã thu được 3.291 cá mối hoa (Trachinocephalus myops) và 4.017 cá thể tôm bộp (Metapenaeus affinis) để phân tích chiều dài, đồng thời sử dụng phương pháp đánh giá khả năng chọn lọc của Wileman để xác định các tham số chọn lọc của 2 đối tượng khai thác. Kết quả nghiên cứu cho thấy, chiều dài cá mối hoa với xác suất 50% (L50) bị đánh bắt của các mẫu lưới M1, M2 và M3 lần lượt là 61,5 mm, 67,5 mm và 71,9 mm; chiều dài tôm bộp (L50) bị đánh bắt tương ứng là 50,7 mm, 61,2 mm và 66,8 mm. Hệ số chọn lọc (SF) được lựa chọn đối với cá mối hoa là 3,42 và tôm bộp là 2,82. Kích thước mắt lưới hình thoi cho nghề lưới đáy phù hợp để khai thác cá mối hoa ứng với L50 là 42 mm và tôm bộp là 36 mm. Từ khóa: Cà Mau, chọn lọc của ngư cụ, kích thước mắt lưới, nghề lưới đáy. Abstract The study utilized 3 net samples with cod-end mesh sizes of 18 mm, 20 mm, 24 mm and 04 mm mesh size of cover, to conduct 30 experimental hauls in Ngoc Hien district, Ca Mau province for data collection. The fishing process yielded 3,291 individual snakefish (Trachinocephalus myops) and 4,017 individual jinga shrimp (Metapenaeus affinis) for length analysis, and the Wileman selectivity method was employed to determine selective parameters of these two target species. The research results show that the fish length of snakefish at 50% capture probability (L50) for net samples M1, M2, and M3 were 61.5 mm, 67.5 mm, and 71.9 mm, respectively, the corresponding lengths (L50) for jinga shrimp were 50.7 mm, 61.2 mm, and 66.8 mm. The selection factor (SF) of the diamond chosen for snakefish was 3.42, and for Jinga shrimp, it was 2.82. The appropriate diamond mesh size for harvesting nakefish corresponding to L50 is 42 mm, and 36 mm for Jinga shrimp. Key words: Ca Mau province, fishing gear selectivity, mesh size, stow net fishery.

Lepidotrigla smithii Regan 1905, a senior synonym of Lepidotrigla kishinouyi Snyder 1911 (Actinopterygii: Teleostei: Triglidae)

2025-06-18

Junya Higuchi , Toshio Kawai | Ichthyological Research

Đánh giá tính chọn lọc và tác động khai thác cá chưa trưởng thành của các cỡ mắt lưới rê phổ biến trong nghề cá ven bờ Phan Thiết, Việt Nam

2025-06-18

Vu Ke Nghiep | Tạp chí Khoa học - Công nghệ Thủy Sản Trường Đại học Nha Trang

Nghề lưới rê ven bờ đóng góp quan trọng vào sinh kế của ngư dân ven biển tại thành phố Phan Thiết, tỉnh Bình Thuận, tuy nhiên, hoạt động này … Nghề lưới rê ven bờ đóng góp quan trọng vào sinh kế của ngư dân ven biển tại thành phố Phan Thiết, tỉnh Bình Thuận, tuy nhiên, hoạt động này đang đối mặt với nguy cơ khai thác quá mức cá nổi nhỏ chưa trưởng thành do việc sử dụng mắt lưới nhỏ, trong khi dữ liệu định lượng về tác động của việc sử dụng lưới với kích thước mắt lưới nhỏ tại địa phương còn thiếu. Vì vậy, nghiên cứu này nhằm đánh giá mức độ khai thác cá chưa trưởng thành và xác định các tham số chọn lọc (chiều dài cá tối ưu, hệ số chọn lọc) của bốn cỡ mắt lưới rê đơn phổ biến (24, 26, 30, 34 mm) đối với bốn đối tượng khai thác chính là cá trích (Sardinella jussieu), cá mòi (Konosirus punctatus), cá nục sồ (Decapterus maruadsi), cá bạc má (Rastrelliger kanagurta). Để thực hiện mục tiêu này, nhóm nghiên cứu đã thu thập dữ liệu của 160 mẻ lưới (trong tháng 04/2022 và tháng 5/2022) và phân tích chiều dài (tính từ đầu mõm đến chẽ vây đuôi) của 6.995 cá thể, đồng thời áp dụng phương pháp Holt (1963) để xác định khả năng chọn lọc. Kết quả phân tích cho thấy một tỷ lệ lớn cá chưa trưởng thành bị khai thác, đặc biệt với lưới có kích thước mắt lưới là 24mm (>98%) và 26mm (>92%), bởi vì chiều dài cá tối ưu của hai cỡ lưới này thấp hơn đáng kể so với chiều dài thành thục sinh dục của các loài nghiên cứu. Ngay cả với lưới có kích thước mắt lưới là 30mm và 34mm, chiều dài cá tối ưu cũng thấp hơn chiều dài thành thục sinh dục đối với hầu hết các loài nghiên cứu (ngoại trừ cá trích ở mức độ nhất định), với hệ số chọn lọc dao động từ 3,5÷3,7. Điều này hàm ý rằng việc sử dụng phổ biến các cỡ mắt lưới rê nhỏ tại Phan Thiết dẫn đến tính chọn lọc kém đối với cá thể non, gây áp lực khai thác nghiêm trọng lên khả năng tái tạo nguồn lợi, do đó nghiên cứu này cung cấp cơ sở khoa học cho việc điều chỉnh quy định quản lý ngư cụ nhằm đảm bảo tính bền vững cho nghề lưới rê ven bờ tại địa phương nghiên cứu. Từ khóa: Cá chưa trưởng thành, kích thước chọn lọc, lưới rê, Phan Thiết, quản lý nghề cá. Abstract The coastal gillnet fishery is crucial for the livelihoods of fishers in Phan Thiet City, Binh Thuan Province. However, this activity faces the risk of overexploiting juvenile small pelagic fish due to the prevalent use of small mesh sizes, while quantitative data on the local impact of such practices remains lacking. Therefore, this study aimed to assess the exploitation level of immature fish and determine the selectivity parameters (optimal length, Lopt; selection factor, SF) for four common mesh sizes of monofilament gillnets (24, 26, 30, and 34 mm) for four key target species: Goldstripe sardinella (Sardinella jussieu), Dotted gizzard shad (Konosirus punctatus), Japanese scad (Decapterus maruadsi), and Indian mackerel (Rastrelliger kanagurta). Data were collected from 160 fishing hauls from April to May 2022, analyzing the fork length (FL) of 6,995 individuals. Holt’s (1963) method was employed to estimate gear selectivity. The results revealed a high proportion of immature fish being caught, particularly by the 24 mm (>98%) and 26 mm (>92%) mesh sizes, as their optimal retention lengths (Lopt) were considerably lower than the length at first maturity (Lm) for the target species. Even with the 30 mm and 34 mm meshes, the Lopt remained lower than the Lm for most species (with S. jussieu being a partial exception), and selection factors (SF) ranged from 3.5–3.7. This implies that the widespread use of small-mesh gillnets in Phan Thiet results in poor selectivity towards juveniles, exerting significant fishing pressure on stock recruitment potential. Consequently, this study provides a crucial scientific basis for revising fishing gear regulations to ensure the sustainability of the local coastal gillnet fishery. Key words: Juvenile fish, Size selectivity, Gillnet, Phan Thiet, Fisheries management

Study of the Physical and Chemical Properties and Accumulation of Heavy Elements in the Fishes and Water of the Tigris and the Lower Zab Rivers in Iraq

2025-06-18

Fatima Hassan Sultan Mohammed , Trifa M. Ahmed | Asian Journal of Environment & Ecology

Estimation and Measurement of some physical and chemical properties and heavy elements of the water and fishes of Tigris and Lower Zab rivers in Iraq. A Cross-Sectional Analytical Study (field … Estimation and Measurement of some physical and chemical properties and heavy elements of the water and fishes of Tigris and Lower Zab rivers in Iraq. A Cross-Sectional Analytical Study (field sampling with repeated measures). The study was carried out during the period between September 2024 and February 2025 in four stations. The samples were collected from the area of confluence of the lower Zab River with the Tigris River and the areas near it using polyethylene pots with a size of 2.25L to measure some physical and chemical properties. The averages of the values of turbidity, pH, nitrates, phosphates, total Alkalinity and potassium ranged between (57.183-72.585), (7.7983 - 7.9683), (1.35083- 1.8193), (1.2563-1.8263), (85.64016- 94.8045), (1.353 -1.4801) respectively As for heavy elements, copper, zinc, lead and iron were measured in water, and the results of the average values of copper, lead and iron in water were between, (0.115783 - 0.1587906) , (0.08913 - 0.1476) , (0.0511-0.1230) , (0.0906 -0.1463) respectively In the fish, four types of fish were collected, namely golden sea bass, Common carp, Grey Mullet and Iraqi Shilag fish, and their average sizes ranged between (13.2325- 65.7475 ) cm and their average weight between (115.4000-1357.1250) g and heavy elements in fish, the average values of copper, zinc, lead and iron ranged between (0.0161 - 0.0283). (0.1063 -0.1735), (0.0044 - 0.070), (0.1171 - 0.1715) respectively. Inconclusion the proportions of physical and chemical properties and heavy elements were differed according to the difference in temperature and the rainfall rates, as well as the impact of the lower Zab River on the Tigris River in that region, which flows into it, so the heavy elements reach fish through the food chain, as heavy elements move from water to phytoplankton. So, the fish and water have a comparable heavy elements ratio.

Alarming decline of fish fauna in the Iranian Caspian Basin

2025-06-18

Asghar Abdoli , Gohar Aghaie | Zoology in the Middle East

The collection of Sri Lankan freshwater fishes reported on by Pieter Bleeker (1863) (Osteichthyes: Cyprinidae, Danionidae, Nemacheilidae)

2025-06-18

Hiranya Sudasinghe , Maurice Kottelat , Rohan Pethiyagoda | Zootaxa

The whereabouts of the types of the six species of Sri Lankan cypriniform fishes described by Pieter Bleeker in 1863 have long remained unknown. These specimens are now reported from … The whereabouts of the types of the six species of Sri Lankan cypriniform fishes described by Pieter Bleeker in 1863 have long remained unknown. These specimens are now reported from the collection of the Naturalis Biodiversity Centre in Leiden, the Netherlands. Here we provide meristic and morphometric data on (as well as photographs of) the type specimens in this collection. These include the three syntypes of Garra ceylonensis, the holotype of Systomus pleurotaenia, the holotype of Devario micronema, one of the three syntypes of Devario lineolatus, and the three syntypes of Schistura notostigma. The five syntypes of Plesiopuntius bimaculatus, though present, are in a very poor state. Devario lineolatus (Bleeker), for which the replacement name D. monticola has previously been proposed, is a junior subjective synonym of D. malabaricus (Jerdon). Devario micronema is the species that occurs in the lowlands of south-western Sri Lanka. An examination of the three syntypes of Schistura notostigma shows it to be distinct from S. madhavai and S. scripta.

Màu sắc bể nuôi – yếu tố quan trọng ảnh hưởng đến sinh trưởng, tỷ lệ sống và màu sắc của cá khoang cổ đỏ (Amphiprion frenatus)

2025-06-18

Nguyễn Đức Khánh Dương , Nguyễn Đức Thọ , Dũng Trần Văn +1 more | Tạp chí Khoa học - Công nghệ Thủy Sản Trường Đại học Nha Trang

Màu sắc bể nuôi là một yếu tố môi trường quan trọng, ảnh hưởng đến sinh trưởng, biến thái, tỷ lệ sống và chất lượng màu sắc của cá. Nghiên … Màu sắc bể nuôi là một yếu tố môi trường quan trọng, ảnh hưởng đến sinh trưởng, biến thái, tỷ lệ sống và chất lượng màu sắc của cá. Nghiên cứu này được thực hiện nhằm đánh giá ảnh hưởng của màu sắc bể nuôi (xanh dương, trắng, trong, đỏ, đen) lên các chỉ tiêu sinh trưởng, biến thái, tỷ lệ sống và hàm lượng carotenoids tích lũy (TCA) ở ấu trùng cá khoang cổ đỏ (Amphiprion frenatus). Kết quả cho thấy bể màu xanh dương và trắng có tác động tích cực nhất đến sinh trưởng và phát triển của cá. Cụ thể, cá được ương trong bể xanh dương đạt tốc độ tăng trưởng đặc trưng về chiều dài (SGRL: 3,77 ± 0,04%/ngày) và khối lượng (SGRW: 5,85 ± 0,09%/ngày), cùng tỷ lệ biến thái (MR3-D20: 58,67 ± 2,40%) và tỷ lệ sống (SR: 17,43 ± 0,33%) cao nhất. Ngoài ra, bể màu xanh dương và trắng giúp cải thiện màu sắc da (L*: 42,90 ± 0,91, a*: 15,11 ± 0,52) và tăng hàm lượng carotenoids tổng số tích lũy (TCA: 39,74 ± 1,29 µg/g; P < 0,05). Ngược lại, cá được ương trong bể đen ghi nhận các chỉ tiêu sinh trưởng, tỷ lệ sống và chất lượng màu sắc thấp nhất, với tốc độ tăng trưởng khối lượng chỉ đạt 4,72 ± 0,07%/ngày, tỷ lệ biến thái MR1-D40 là 28,33 ± 3,38%, và hàm lượng TCA tích lũy chỉ đạt 32,80 ± 1,73 µg/g (P < 0,05). Kết quả này khẳng định rằng việc lựa chọn màu sắc bể nuôi phù hợp, đặc biệt là màu xanh dương và trắng, có thể tối ưu hóa hiệu suất nuôi và chất lượng con giống của cá khoang cổ đỏ. Từ khóa: Màu sắc bể ương, cá khoang cổ đỏ, sinh trưởng, tỷ lệ sống, biến thái, chất lượng màu sắc. Abstract The tank color is a critical environmental factor influencing growth, metamorphosis, survival rate, and skin coloration quality in fish. This study aimed to evaluate the effects of tank color (blue, white, transparent, red, black) on growth performance, metamorphosis, survival rate, and total carotenoids accumulation (TCA) in the larvae of the tomato clownfish (Amphiprion frenatus). The results showed that blue and white tanks had the most positive effects on the growth and development of the fish. Specifically, the blue tank achieved the highest specific growth rates in length (SGRL: 3.77 ± 0.04%/day) and weight (SGRW: 5.85 ± 0.09%/day), as well as metamorphosis rate (MR3-D20: 58.67 ± 2.40%) and survival rate (SR: 17.43 ± 0.33%). Additionally, blue and white tanks improved skin coloration (L*: 42.90 ± 0.91, a*: 15.11 ± 0.52) and increased total carotenoid accumulation (TCA: 39.74 ± 1.29 µg/g; P < 0.05). In contrast, black tanks recorded the lowest growth performance, survival rates, and skin coloration, with specific growth rates in weight of only 4.72 ± 0.07%/day, metamorphosis rate (MR1-D40) of 28.33 ± 3.38%, and TCA accumulation of 32.80 ± 1.73 µg/g (P < 0.05). These findings confirm that selecting appropriate tank colors, particularly blue and white, can optimize rearing performance and seed quality in tomato clownfish. Keywords: Tank color, Amphiprion frenatus, growth, survival rate, metamorphosis, coloration quality.

Ficha de Hyalella caeca

2025-06-17

Alessandra Angélica de Pádua Bueno , Rafaela Bastos Pereira , Tamires Zepon +3 more | Datasets - Sistema SALVE - ICMBio

Novel complete mitochondrial genomes of eight riverine Lamprologus species (Actinopterygii, Cichlidae) suggest in-situ speciation of the blind cichlid L. lethops in the lower Congo River

2025-06-17

Sebastián Jiménez , Naoko Kurata , Melanie L. J. Stiassny +3 more | Mitochondrial DNA Part B

Lamprologine cichlids include nearly 100 species from Lake Tanganyika, but only nine are known from the Congo River, including Lamprologus lethops, the only known blind cichlid. Little is known about … Lamprologine cichlids include nearly 100 species from Lake Tanganyika, but only nine are known from the Congo River, including Lamprologus lethops, the only known blind cichlid. Little is known about its natural history. We characterized the complete mitochondrial genomes of L. lethops and seven related riverine species to infer evolutionary relationships. Genomes were similar in size and structure. Riverine Lamprologus formed two non-sister mitochondrial lineages more closely related to Lake Tanganyika lamprologines than to each other, suggesting past introgression or incomplete lineage sorting. Lamprologus lethops was sister to lower Congo River species. Broader taxonomic and genomic sampling is needed.

Transcriptome analysis of glyptosternum maculatum (sisoridae: siluriformes) provided insights into sexual dimorphism, Xizang, China

2025-06-17

Hong-di He , Mengyu Wu , Zhuangzhuang Wang +2 more | Fish Physiology and Biochemistry

Assessment of Growth and Mortality Parameters of Four Commercial Fish Species from Lekki Lagoon Nigeria

2025-06-17

Tivfa Samuel Gbaior , W. O. Abdul , Umar Alabi +3 more | Mediterranean fisheries and aquaculture research.

This study assessed the growth and mortality parameters of four commercial fish species (Chrysichthys ni-grodigitatus (Lacepède, 1803), Coptodon zillii (Gervais, 1848), Ethmalosa fimbriata (Bowdich, 1825) and Elops lacerta (Valenciennes, 1847) … This study assessed the growth and mortality parameters of four commercial fish species (Chrysichthys ni-grodigitatus (Lacepède, 1803), Coptodon zillii (Gervais, 1848), Ethmalosa fimbriata (Bowdich, 1825) and Elops lacerta (Valenciennes, 1847) from Lekki Lagoon, Nigeria. Fish specimens were collected monthly from five landing sites (Wharf, Agbalegiyo, Ebute-Oni, Ilumofin and Luboye). Specimens were collected us-ing proportional sampling based on the level of fishing activities between January and December, 2022. Es-timation of growth parameters was performed according to the growth equation: Lt = L∞- (1- e-K(t-to)) by von Bertalanffy with the Length Frequency Data Analysis (LFDA) package. The length-converted catch curve model was adopted for the estimation of mortality parameters using FiSAT II software. Results showed that C. nigrodigitatus exhibited the highest growth rate (K = 1.30 yr⁻¹) and exploitation rate (E = 0.83) with an as-ymptotic length (L∞) of 53.94 cm. However, C. zillii exhibits the lowest growth curvature (K = 0.44 yr⁻¹) with L∞ = 39.15 cm and an exploitation rate of 0.42. E. fimbriata showed a rapid growth rate (K = 1.15 yr⁻¹) but low exploitation (E = 0.12), while E. lacerta exhibited moderate growth rate (K = 0.58 yr⁻¹) and low exploita-tion (E = 0.16). It is concluded that C. nigrodigitatus is overfished in the lagoon, which demands a closed season and small mesh size restriction to prevent recruitment overfishing. The low exploitation levels of E. fimbriata and E. lacerta means that these stocks are currently sustainable, but there is a need to monitor them to avoid future over-exploitation.

Preliminary Study on Size Structure and Condition Factor of Oreochromis niloticus (Cichlidae) in the Ayame 2 Man-made Lake, Côte d’Ivoire

2025-06-17

Adou Yedehi Euphrasie , Kassi Georges Blahoua | Journal of Advances in Biology & Biotechnology

The Ayame 2 lake, located in southeastern Côte d’Ivoire, is a tropical lentic ecosystem characterized by strong seasonal fluctuations and pronounced eutrophication, particularly during the dry seasons (December-March and August-September). … The Ayame 2 lake, located in southeastern Côte d’Ivoire, is a tropical lentic ecosystem characterized by strong seasonal fluctuations and pronounced eutrophication, particularly during the dry seasons (December-March and August-September). This study aimed to assess the size structure and condition factor of Oreochromis niloticus, a key economic fish species, in order to better understand its population dynamics and physiological status in this fluctuating environment. A total of 1888 O. niloticus individuals were sampled monthly from January to December 2017 at various artisanal fishing sites around the lake. Total length (cm) and body weight (g) were recorded for each specimen to assign size classes and calculate the condition factor (K). The results revealed a size distribution dominated by intermediate classes ([10.5-12.5[ cm), indicating active recruitment but a reduced number of larger individuals (>22.5 cm). The condition factor varied significantly by month and size class (p < 0.05), with highest values observed during the rainy seasons and marked lows during the dry season. The highest mean K (1.90) was found in the [10.5-12.5[ cm class, while larger size classes showed extremely low values (as low as 0.01). These findings highlight the significant influence of seasonal environmental conditions on the morphophysiology of O. niloticus and underscore the need for integrated management strategies considering size at capture, breeding seasons, and habitat quality.

Population genetics of two endemic loach species, Iksookimia hugowolfeldi and I. longicorpa (Cypriniformes, Cobitidae), illuminate taxonomy, paleo-drainages, and river capture in the southern Korean Peninsula

2025-06-17

Da-Song Choi , Hyo-Jin Kim , Myeong‐Hun Ko +2 more | Zoosystematics and Evolution

Pleistocene climatic fluctuations reshaped the East Asian coastline, facilitating the formation of extensive paleo-river networks that influenced freshwater biodiversity. Here, we examine how the formation of ancient river systems has … Pleistocene climatic fluctuations reshaped the East Asian coastline, facilitating the formation of extensive paleo-river networks that influenced freshwater biodiversity. Here, we examine how the formation of ancient river systems has influenced the population genetic structures of two sister species of freshwater loaches, Iksookimia hugowolfeldi and I. longicorpa , found in the southern Korean Peninsula. We conducted a multi-locus genetic analysis of an extensive sample of 208 individuals from 21 populations across their entire distribution range. According to a phylogenetic tree constructed using nuclear DNA, the two sister species diverged approximately 5.5 million years ago. However, there was a discrepancy between the taxonomic identification of I. hugowolfeldi populations and the phylogenetic result. A wrong species boundary between the two sister species previously assumed and a genetic signature of headwater river capture were found to explain the discrepancy. An overall radiative diversification of multiple allopatric genetic clusters in the sister species highlights the significant influence of geographic barriers in today’s isolated river systems. Simulations of ancient river connections, shaped by fluctuating sea levels, compellingly illustrate how localized reconnections through these historic networks during the ice ages have significantly shaped the population genetic structures of these sister species. The present study identifies the important role of paleo-river systems in facilitating the geographic connectivity of Iksookimia , which provides useful insights into the broader phylogeography of other riverine organisms in the Korean Peninsula and East Asia.

Impact of Wetland Ecosystems on Freshwater Fish Assemblages in the Perlis River Basin, Peninsular Malaysia

2025-06-17

Nurhidayah Azlan-Hisham , Muhamad Syafiq , Mohamad Aqmal-Naser +1 more | Wetlands

Taxonomic revision of Paralaubuca (Cypriniformes, Xenocyprididae), a taxon seemingly in decline

2025-06-17

Weerapongse Tangjitjaroen , Zachary S. Randall , Lei Yang +2 more | Zootaxa

Although eight species names are available for the Southeast Asian genus Paralaubuca, and four names currently are in use, morphological and molecular data support recognition of only three names as … Although eight species names are available for the Southeast Asian genus Paralaubuca, and four names currently are in use, morphological and molecular data support recognition of only three names as valid, P. typus Bleeker, 1864, P. harmandi Sauvage, 1883, and P. barroni Fowler, 1934. Paralaubuca harmandi is easily distinguished from P. typus and P. barroni by having more lateral-line scales (70–87 vs. 51–68), fewer branched anal-fin rays (usually 22–24 vs. usually 24–28), and more scales around the caudal peduncle (usually 26–33 vs. usually 20–26). Paralaubuca typus and P. barroni are morphologically similar but can be separated consistently by number of rakers on the first gill arch, with P. typus having 31–51, and P. barroni having 22–29. Paralaubuca harmandi and P. typus are also separated by a COI genetic p-distance of 6.86–8.79%; molecular data are not available for P. barroni. Paralaubuca typus and P. harmandi have been recorded from the Chao Phraya, Mekong, and Mae Klong River basins, but both species appear now to be absent from the Mae Klong basin, not having been recorded there since 1966. Paralaubuca harmandi appears to be extremely rare in the Mekong River basin, where it has been documented at only two localities and not recorded since 1968. Paralaubuca barroni is found only in the Mekong River basin and documented at only three localities.

Report of the Titan Cardinal fish Holapogon maximus (Boulenger, 1888) from Chennai coast of India, Bay of Bengal

2025-06-16

S. Beura , Bineesh KK | Species

POPULATION CONNECTIVITY OF VULNERABLE BRAZILIAN PARROTFISHES

2025-06-16

Karis Itchel Tuñón Valdés , Juliana Beltramin De Biasi , Natália Carvalho Roos +7 more | Marine Environmental Research

Ảnh hưởng của một số yếu tố trong quá trình sản xuất đến chất lượng surimi từ cá nục thuôn (Decapterus macrosoma Bleeker, 1851)

2025-06-16

Doãn Dũng Lê , Thérèse Truong , Nguyen H. Tran | Dong Thap University Journal of Science

Surimi là chất nền protein dùng để sản xuất thực phẩm mô phỏng, thực phẩm tái cấu trúc, một loại thực phẩm ngày nay đang được ưu chuộng ở nhiều … Surimi là chất nền protein dùng để sản xuất thực phẩm mô phỏng, thực phẩm tái cấu trúc, một loại thực phẩm ngày nay đang được ưu chuộng ở nhiều nước trên thế giới. Quy trình tóm tắt để sản xuất surimi bao gồm thịt cá được xay nhỏ, rửa qua một số lần để loại bỏ chất phiprotein, sau đó phối trộn, nghiền giã với một số loại phụ gia khác như tinh bột, lòng trắng trứng, gelatin, sorbitol…Cho đến nay đã có một số công trình nghiên cứu thử nghiệm sản xuất surimi từ các loại cá khác nhau, nhưng chưa có công trình nghiên cứu nào sử dụng nguyên liệu là cá nục thuôn. Nghiên cứu này nhằm mục đích xác định một số điều kiện tốt nhất để sản xuất surimi từ cá nục thuôn. Thí nghiệm được bố trí để khảo sát nồng độ acid acetic trong nước rửa, tỷ lệ phối trộn lòng trắng trứng, tỷ lệ phối trộn tinh bột trong quá trình phối trộn, khảo sát nhiệt độ và thời gian sấy để tạo ra surimi có cường độ gel tốt nhất. Kết quả cho thấy nồng độ acid acetic trong nước rửa là 0,04% làm cho surimi có chất lượng cảm quan, pH và độ ẩm phù hợp nhất, đạt tiêu chuẩn chất lượng surimi theo TCVN 8682:2011. Ở tỷ lệ phối trộn lòng trắng trứng 4,5%; tinh bột 4,0%, sorbitol 1,0% và STPP 0,2% làm cho surimi có cường độ gel tốt nhất (1.403,9 g.cm). Khi khảo sát điều kiện sấy, surimi có cường độ gel cao nhất ở nhiệt độ sấy 1000C và thời gian sấy 30 phút. Cường độ gel của surimi ở nhiệt độ sấy, thời gian sấy này là 1.265,4 g.cm.

A Study on Cadmium Accumulation in the Fingerlings of Asian Seabass Lates calcarifer (Bloch)

2025-06-16

V. Mohan Raj , A. R. Thirunavukkarasu , M. Kailasam +2 more | Asian Journal of Current Research

Heavy metals remain in the environment for extended periods, taint food chains, and lead to various health issues because of their toxic nature. Organisms face significant dangers from prolonged exposure … Heavy metals remain in the environment for extended periods, taint food chains, and lead to various health issues because of their toxic nature. Organisms face significant dangers from prolonged exposure to these environmental heavy metals. Excessive exposure to heavy metals in marine ecosystems can adversely affect marine life and pose risks to humans who consume seafood. Cadmium a non-essential metal that are toxic, even in trace amounts. One of the key groups for transferring metals to humans is thought to be fish, which are typically found in the lower rungs of the food chain. In this study, we conducted a 60-day experiment to investigate the accumulation of cadmium in various tissues of seabass Lates calcarifer, a commercially important fish species. The study's results show that cadmium concentration in L. calcarifer tissues is highest in liver, followed by gill, and then muscle. The effects of L. calcarifer are influenced by the dosage and duration of administration, with liver, gill, and muscle are being the primary sites of action.

Ficha de Thamnophilus caerulescens cearensis

2025-06-16

Helder Farias Pereira de Araújo , Alexandre M. Fernandes , Antonio Emanuel Barreto Alves de Sousa +7 more | Datasets - Sistema SALVE - ICMBio

Culture performance and financial business of leopard coral (Plectropomus leopardus), humpback (Cromileptes altivelis), and brown-marbled (Epinephelus fuscoguttatus) grouper nursery

2025-06-16

Belinda Astari , Darmawan Setia Budi , Suko Ismi +5 more | Aquaculture Reports

Exploring the Stock Status of Big Eye Scad (Selar crumenopthalmus Bloch, 1793) Fishery after A Lobster Stock Decline in Gunungkidul Waters: A Length-Based Approach

2025-06-16

Tirtadanu Tirtadanu , Andina Ramadhani Putri Pane , Duranta Diandria Kembaren +5 more | Thalassas An International Journal of Marine Sciences

Length-weight relationships of 17 demersal fish species in the Canary Islands (Spain, CE Atlantic).

2025-06-16

Alba Jurado‐Ruzafa , Pablo Martín-Sosa | Vieraea Folia scientiarum biologicarum canariensium

Ten scientific surveys were carried out at ‘Isla de La Palma’ and ‘La Graciosa e Islotes al Norte de Lanzarote’ Marine Protected Areas (MPAs) between 2003 and 2010. Length-Weight Relationships … Ten scientific surveys were carried out at ‘Isla de La Palma’ and ‘La Graciosa e Islotes al Norte de Lanzarote’ Marine Protected Areas (MPAs) between 2003 and 2010. Length-Weight Relationships (LWR) were estimated for 17 fish species using individual fish records collected by fish pots (half an inch mesh size), bottom horizontal longlines (hook size 3/0) and set gillnets (80 mm mesh size). Fish was measured fresh for the total length (to the lower 0.1 or 0.5 cm, depending on the scientific surveys design) and weighted for the total weight (TW, to the 0.1 g). Except for the Myliobatiformes species (with b-values lower than 2.0), the b-value varied between 2.63 and 3.72. All LWRs were obtained from well adjusted linear regressions with R² ≥0.74. In addition, two new maximum lengths were recorded. Data presented herein expand the knowledge base for these species in the Archipelago, where any status assessment of the species affected by the operating fisheries has been possible so far, and remain as datapoor stocks.

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Description of two new species of Chiloglanis (Teleostei, Mochokidae) from the Eastern Zimbabwe Highlands freshwater ecoregion: an overlooked hotspot of rheophilic fishes

2025-06-16

Tadiwa I. Mutizwa , Taurai Bere , Wilbert T. Kadye +2 more | ZooKeys

Growing evidence indicates that species diversity within the genus Chiloglanis Peters 1868 is poorly resolved and major taxonomic revisions are required. By integrating genetic and morphological analyses, this study describes … Growing evidence indicates that species diversity within the genus Chiloglanis Peters 1868 is poorly resolved and major taxonomic revisions are required. By integrating genetic and morphological analyses, this study describes two new Chiloglanis species from the Eastern Zimbabwe Highlands (EZH) freshwater ecoregion, a region that, until only recently, had been poorly-explored in terms of its ichthyological diversity. Chiloglanis asperocutis Mutizwa, Bragança & Chakona, sp. nov. is distinguished from other southern African congeners by a combination of characters, including ridge-like tubercles distributed on the dorsal and lateral surfaces of the head and body giving the skin a conspicuously rough texture, ten closely packed mandibular teeth, deeply forked caudal fin and a high number of primary premaxillary teeth (68–128). Chiloglanis compactus Mutizwa, Bragança & Chakona, sp. nov. , attains the smallest size (&gt; 46 mm SL) of all currently known congeners in southern Africa. It is distinguished from all the other congeners from the region by a combination of characters; the possession of seven pectoral fin rays, conical tubercles distributed across the dorsal and lateral surface of the head and body, eight widely spaced mandibular teeth, a shallow forked caudal fin with rounded lobes, a low number of primary premaxillary teeth (31–53) and fewer dorsal fin rays (5). These two species are distributed in both the Buzi and Pungwe River systems. The study is the first in a series of publications that will provide formal descriptions of a number of deeply divergent lineages (candidate species) identified in previous studies from southern Africa. The persistence of the unique riverine fauna in the EZH is threatened by multiple impacts that are altering the hydrological regime of the rivers and streams as well as habitat degradation and excessive sedimentation from gold panning and agricultural activities.

Report on the present status of ichthyofaunal diversity in and around Brahmapuri, Central India

2025-06-16

Lalit Urkude , Sudhir Bhandarkar , Gopal Paliwal +1 more | Species