The Indian Journal of Fisheries is published quarterly by the Indian Council of Agricultural Research (ICAR). Original contributions in the field of fish and fisheries science will be considered for publication in the Journal. The material submitted must be unpublished and not under consideration for publication elsewhere. Papers based on research which kills or damages any species, regarded as threatened/ endangered as per IUCN criteria or is as such listed in the Red Data Book appropriate to the geographic area concerned, will not be accepted by the Journal, unless the work has clear conservation objectives Editorial Board Editors
Central Marine Fisheries Research Institute (on behalf of Indian Council of Agricultural
The copyright of the articles published in Indian Journal of Fisheries vests with the Indian Council of Agricultural Research, who has the right to enter into any agreement with any organization in India or abroad engaged in reprography, photocopying, storage and dissemination of information contained in these journals. The Council has no objection in using the material, provided the information is being utilized for academic purpose but not for commercial use. Due credit line should be given to the ICAR where information will be utilized.
Production, export and competitiveness of fish and fishery products in India: An analysis across technology and policy phases
India's marine product sector has seen significant growth, benefiting consumers, boosting foreign exchange earnings, and supporting livelihoods. This progress is attributed to the research and development (R&D) efforts and the supportive policies. The Government of India has implemented targeted schemes to enhance fish production and exports, drawing from past experiences to inform future strategies. This study identifies five structural breaks in fish production and exports, coinciding with shifts in technology, policy, and institutions. From 1980–81 to 2018–19, national fish production increased annually by 6.3% for inland fish and 2.4% for marine fish. However, production performance varied widely across states. The study examines export performance in terms of growth, instability, and competitiveness, revealing variations across product groups and structural break periods since 1995. Although marine products exports show competitiveness according to revealed comparative advantage (RCA), this advantage has diminished over time. Granger causality analysis indicates a bidirectional causation between fish production and exports, emphasising the importance of comprehensive R&D and policy interventions along the value chain. The study underscores the critical role of enhancing production and value addition through favourable R&D and policies to sustainably boost fish production and its value. Keywords: Fish production, Granger causality, Marine exports, Research and development policy, Structural breaks
Fish production, marine exports, competitiveness, research and development policy, structural breaks, Granger causality
Copyright (c) 2026 Indian Journal of Fisheries https://creativecommons.org/licenses/by-nd/4.0
Structural dynamics of Sri Lankan artisanal tuna fisheries: Evidence from a 73 year time series and econometric analysis
This study employed advanced econometric methods to analyse 73 years (1950-2023) of catch data for skipjack (Katsuwonus pelamis) and yellowfin (Thunnus albacares) tuna from Indian Ocean Tuna Commission (IOTC) database. Bai-Perron tests identified four structural breaks at 1966, 1985, 2005 and 2014 (p<0.01), delineating five developmental phases. Regime switching models revealed differential volatility patterns, with skipjack showing higher volatility. Low volatility regime for skipjack showed mean returns of 0.084 (SD = 0.156, duration 8.7 years) while high volatility regime showed returns of -0.023 (SD = 0.387, duration 4.2 years). Johansen cointegration confirmed long-run equilibrium (trace=23.47, p<0.01) with error correction coefficient -0.31 (half-life 3.2 years). Non-linear ARIMA-GARCH models achieved 42% and 34% MAPE (Mean Absolute Percentage Error) reduction for skipjack and yellowfin respectively versus linear models. These findings demonstrate complex nonlinear catch dynamics, providing robust frameworks for tropical tuna management under changing conditions. Keywords: ARIMA-GARCH models, Econometric analysis, Regime switching, Skipjack tuna, Structural breaks, Yellowfin tuna
Thushani Suleka Madhubhashini Elepathage
Characterization of fish protein concentrate from underutilised red-toothed triggerfish Odonus niger (Ruppell, 1836)
Odonus niger, despite being nutritionally comparable to many commercially important species, continues to remain underutilised in the food sector. Owing to its high content of quality protein, it represents a promising raw material for developing fish protein concentrate (FPC). FPC prepared using a combination method (alkaline sodium bicarbonate washing followed by acetic acid precipitation) was characterised for yield, bulk density (UTBD and TBD), water holding capacity (WHC), oil absorption capacity (OAC), water activity (aw), colour (L*, a*, b*), proximate composition, and amino acid profile. The developed FPC exhibited a proximate composition meeting the requirements mentioned in IS:9808 standards for FPC, containing 89±0.20% crude protein, 9.54±0.10% moisture, 0.36±0.04% crude fat, and 0.31±0.03% ash. A total of 21 amino acids were identified, with essential amino acids including lysine (12.79%), leucine (15.07%) and methionine (13.29%) constituting the major fraction of the total amino acid profile The FPC demonstrated good physicochemical quality with a yield of 13.56±0.38%, UTBD and TBD of 0.65±0.03 and 0.75±0.01 g ml-1, respectively, OAC of 0.79±0.03 g g-1, WHC of 7.96±0.63 ml g-1, aw of 0.40±0.02 and L*, a*, b* values of 76.88±0.36, 3.33±0.53, and 24.43±0.78, respectively. The results demonstrated that the characteristics of the developed FPC were. in agreement with those reported in earlier studies. Therefore converting O. niger into a stable protein preparation represents an effective approach for its optimal utilisation, with potential incorporation into suitable value added food products. Keywords: Amino acid profile, Bulk density, Functional properties, proximate composition, Water activity
Characterisation and evaluation of novel bacterial consortium as a biofloc inoculum for nursery rearing of Labeo rohita and Oreochromis mossambicus
The present study explored isolation, characterisation and formulation of a probiotic bacterial consortium for application as a biofloc inoculum to enhance growth and survivability during seed rearing of rohu (Labeo rohita) and tilapia (Oreochromis mossambicus). Six potential probiotic bacterial strains viz., Priesta aryabhattai, Bacillus cereus, Exiguobacterium indicum, Acinetobacter indicus, Mixta calida, and Bacillus altitudinus, were isolated from autochthonous sources and identified using 16s rDNA PCR, sequencing and phylogenetic analysis. The probiotic potential of these bacterial isolates was assessed through comprehensive in vitro assays along with safety analyses. All the isolates and their combination exhibited antimicrobial potency against important fish pathogens; tolerance to a wide range of pH and bile concentrations and strong adhesion properties including autoaggregation, co-aggregation,biofilm formation capacity, and cell surface hydrophobicity. All the isolates were non-haemolytic, non-pathogenic to fish when at high doses (5x109 cells) and demonstrated significant free radical scavenging activity. Further, all the isolates showed tolerance to ammonia, nitrite and nitrate and ability to grow on fish mucus. The efficacy of the consortium was further validated through fry to fingerling rearing trials in biofloc systems for rohu (L. rohita) and tilapia (O. mossambicus), with jaggery as a carbon source. Fish fry were stocked at one fish per litre and reared for 90 days without water exchange and fed with feed containing 30% crude protein. On termination of the experimental trial, higher survival rates 80% for rohu and 100% for tilapia, were observed in the treatment groups, compared to control groups (71% for rohu and 92% for tilapia. The present study highlights the effective utilisation of a bacterial consortium as biofloc inoculum for seed rearing of rohu and tilapia, along with improved growth performance. The study demonstrated effectiveness of the bacterial consortium as a biofloc inoculum for enhancing seed rearing efficiency in rohu and tilapia. Keywords: Probiotics, Adhesion properties, Growth performance, Rohu, Seed rearing, Survival, Tilapia
Biofloc; Labeo rohita; Oreochromis mossambicus; Probiotics; Survivability; Seed rearing.
Comparative analysis of MHC class II A gene in Trachinotus mookalee and Trachinotus blochii: Molecular identification and in silico characterisation
Trachinotus mookalee and Trachinotus blochii are the two commercially important pompano species successfully farmed in aquaculture, and are susceptible to various infectious diseases. As in higher vertebrates, the major histocompatibility complex (MHC) gene superfamily plays crucial role in the adaptive immunity of teleost fishes by mediating the recognition and presentation of pathogen derived antigens to T cells, thereby contributing to disease resistance. The present study reports the identification and in-silico characterisation of the MHC class II A gene in T. mookalee (Trmo-DAA) and T. blochii (Trbl-DAA). The coding region of the target gene in both species was 1026 bp in length, comprising 4 exons and encoding a polypeptide of 241 amino acids. Phylogenetic analysis revealed that the MHC II A gene of T. blochii is more closely related to Trachinotus ovatus than to T. mookalee. In-silico analysis highlighted that the target gene is involved in the processing and presentation of exogenous antigen, as supported by domain and motif prediction, Gene Ontologies (GO) annotation, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis and STRING-based protein-protein interaction networks. The predicted secondary structure (2D) majorly comprised random coils and β strands, while the tertiary structure (3D) showed the highest similarity to the MHC class II A protein of Lates calcarifer. Ramachandran plot validation suggested that the predicted 3D structure of Trbl-DAA exhibits better stereochemical stability than that of Trmo-DAA. These findings provide valuable insights into the molecular and structural characteristics of MHC class II A genes in Trachinotus species and may support future studies on disease resistance and selective breeding. Keywords: Disease resistance, Indian pompano, Selective breeding, Silver pompano, Snubnose pompano, Trmo-DAA, Trbl-DAA
MHC II A; Silver Pompano; Indian Pompano
Biological insights into the vulnerable Hyporhamphus xanthopterus from Vembanad Lake: Fishery trends and growth parameters
This study examined the fishery characteristics, length-weight relationship (LWR), and condition factor of Hyporhamphus xanthopterus (Valenciennes, 1847), T from Kumarakam region of Vembanad Lake, Kerala, during 2020-2021. This investigation provides the first sex-wise analysis of length–weight relationships (LWR) and season-wise evaluation of condition factor (Kn) for H. xanthopterus population. A total of 657 specimens (304 males and 353 females) were caught employing 18 mm mesh sized gillnets, and measured for total length (TL) and total weight (TW) to estimate growth patterns using the allometric model. Males exhibited isometric growth (b=3.004) (R2 =0.94), while females displayed slightly negative allometric growth (b=2.857) and R2=0.96. When all the individuals are pooled, the estimated growth exponent b was 2.918 (R2=0.96). Seasonal analysis of condition factor indicated statistically significant variation, with higher Kn values observed in both males and females during Season 3 (post-monsoon), likely reflecting ecological influences such as food availability, reproductive activity, and environmental stress. These findings highlight distinct sex-specific growth patterns and seasonal physiological shifts, offering valuable insights into the biology and ecological adaptation of H. xanthopterus. The baseline data provided here can inform future research, resource management strategies, and biodiversity conservation efforts targeting H. xanthopterus and the broader aquatic ecosystem of Vembanad Lake. Keywords: Condition factor, Conservation, Length-weight relationship, Management, Ramsar site
Vulnerable, Ramsar site, Length-weight relationship, Condition factor, Conservation, Management
Assessment of reproductive potential and spawning patterns of Barilius bendelisis (Hamilton, 1807) in tributaries of the Ganga River in the Garhwal Himalayan region
Understanding reproductive strategies is essential for the biological conservation and management of hill-stream fishes in dynamic freshwater ecosystems. The present study investigated the reproductive biology of Barilius bendelisis (Hamilton, 1807), a key cyprinid species inhabiting three different streams and tributaries of the Ganga River viz.: the Song River, Sahastradhara, and Henval River in the Garhwal Himalayan region. The study was conducted from September 2023 to May 2025, covering all major seasons. Key reproductive parameters, including sex ratio, gonadosomatic index (GSI), Dobriyal index (DI), fecundity, and sexual dimorphism, were examined to determine spawning periodicity and reproductive potential. A female-biased sex ratio was consistently observed across all sites, with overall sex ratios of 1:1.14, 1:1.1, and 1:1.45 in the Song, Sahastradhara, and Henval Rivers, respectively. Peak GSI and DI values were recorded during the summer and monsoon seasons, indicating these seasons as the primary spawning period, with DI showing greater precision in identifying spawning periods. Fecundity varied among sites and showed a strong positive correlation with gonad weight, reflecting site-specific reproductive investment. Notably, males displayed prominent breeding tubercles during the spawning phase, serving as markers for sexual dimorphism. Overall, the findings reveal spatial variation in reproductive traits and highlight adaptive strategies of B. bendelisis in Himalayan hill-stream ecosystems. These insights offer a scientific foundation for developing season-specific conservation strategies, regulating fishing pressure during peak breeding periods, promoting the sustainable management of freshwater biodiversity in the Garhwal Himalayas. Keywords: Conservation, Dobriyal index, Fecundity, Gonadosomatic index, Hill-stream ecosystems, Indian hill trout, Sexual dimorphism
Morphological and molecular evidence for range extension and taxonomic validation of Sperata aorides (Jerdon, 1849) in the Western Ghats, India
Sperata aorides (Jerdon, 1849) is a commercially important freshwater catfish endemic to the Cauvery River basin, including its tributary, the Bhavani River. The present study report a range extension of the species to the Bharathappuzha River in Kerala, documenting its previously unrecorded distribution based on morphometric and molecular evidence. Specimens for the study were collected from different river systems in the Western Ghats, including the type locality at Erode, Tamil Nadu. Morphometric comparisons revealed minor variations between populations in head proportions, particularly in interorbital distance (19.5-24.5% vs 15.8-22.1% in HL) and eye diameter (12.0-17.3% vs 8.8-17.9% in HL). Mitochondrial cytochrome c oxidase subunit I (COI) gene sequencing confirmed species identity. Phylogenetic analysis showed that S. aorides forms a distinct clade, with low intraspecific genetic divergence (0.19%) between Cauvery and Bharathappuzha populations and higher divergence (4.61-9.85%) from congeners. These findings confirm the taxonomic validity of S. aorides and extend its known distribution to the Bharathappuzha River in the southern Western Ghats. Keywords: Bharathappuzha, Catfishes, COI gene sequencing, Distribution, Tamil Nadu
Filistriatus arabicus, a new species of threadfin (Polynemidae) from the northern Arabian Sea, India
A new species of threadfin, Filistriatus arabicus n. sp., is described based on three specimens (163-315 mm TL) collected from the coastal waters of Maharashtra (India), Arabian Sea. Filistriatus arabicus n. sp. can be distinguished from congeners by the presence of the following characters - 5 pectoral filaments, pectoral filament length 35.4-37.8% SL, reaching to or extending slightly beyond pelvic fin tip; black anterior lateral line spot absent; first dorsal fin with 8 spines, all spines equally robust; second dorsal fin with one spine and 13-14 soft rays; pectoral fin rays 15-16, length 4.5-4.7 in SL, origin below the lower end of maxilla horizontally; anal fin with 3 spines and 11 soft rays. 6-7 dark stripes along the scale rows above the lateral line, 7-8 scales above the lateral line, and 11-12 scales below the lateral line. Lateral line unbranched, 54-58 lateral line scales; 9-11+11-13 (20-24) gill rakers; upper jaw length 15-15.1% SL; distal margin of dorsal fins and pectorals black and anterior margin of pelvic dusky to black. The mitochondrial DNA (COI) sequence of F. arabicus exhibited a 6.6 to 10.3% sequence divergence from closest congeners. Key words: DNA, Filistriatus, Northern Indian Ocean, Polynemidae,Taxonomy
taxonomy, Polynemidae, DNA, Polydactylus, India, Arabian Sea, northern Indian Ocean
Stock discrimination of Indian sand whiting Sillago sihama (Forsskal, 1775) using truss morphometry along the Maharashtra and Goa coasts of India
The present study aimed to assess the stock structure of Sillago sihama (Forsskal, 1775) along the Maharashtra and Goa coasts using truss morphometric analysis. A total of 180 specimens were collected from six locations including Satpati, Mumbai, Harnai, Ratnagiri, Malvan, and Panaji between September 2024 and May 2025.Twenty truss distances, generated from ten anatomical landmarks, were subjected to statistical analyses comprising ANOVA, MANOVA, Principal Component Analysis (PCA), and Discriminant Function Analysis (DFA) to assess morphometric variation among populations. Nineteen out of twenty morphometric traits showed significant variation among locations. PCA revealed that most variation was concentrated in the caudal and dorsal regions, while DFA correctly classified 78.9% of specimens, with 70.6% accuracy in cross-validation. The distinct clustering patterns suggest the presence of multiple morphometric stocks. These results highlight the presence of significant morphological variability among S. sihama populations and underscore the effectiveness of truss morphometry in stock discrimination for sustainable fisheries management. Keywords: Anatomical landmarks, DFA, Fisheries management, Morphometric traits, PCA, Populations, Truss distances
Schizothorax esocinus (Heckel, 1838) in Dal Lake and Jhelum River: physiological traits and population trends in the Kashmir Himalayas
This study investigated the physico-chemical characteristics of Dal Lake and the Jhelum River along with evaluation of the morphometric traits, biometric growth parameters, biological indices, physiological attributes, and biochemical profiles of Schizothorax esocinus populations inhabiting these freshwater systems. The physico-chemical assessment revealed distinct environmental differences between the two habitats, with Dal Lake characterised by relatively warmer water, greater hardness, near-neutral pH, and comparatively lower dissolved oxygen levels than the Jhelum River. Correspondingly, fish from the Jhelum River exhibited greater body size and weight, whereas individuals from Dal Lake showed comparatively smaller morphometric dimensions. Biometric growth analysis indicated positive allometric growth in both populations, with notable variations in growth patterns between the two habitats. Biological indices differed between sites and sexes, reflecting habitat specific reproductive and metabolic conditions. Although haematological parameters showed no marked genderbased differences; however, site and age-related variations were evident, suggesting the influence of environmental conditions on physiological status. Overall, the findings highlight habitat driven differences in environmental quality and associated biological responses in S. esocinus, providing valuable insights for conservation planning and sustainable fisheries management in the freshwater ecosystems of Kashmir. Keywords: Aquatic environment, Condition factor, Hematological indices, Morphometric traits, Physico-chemical parameters
Growth dynamics of the common sole Solea solea, in the Morroccan Atlantic coastal waters
This study investigated the growth parameters, mortality and exploitation rate among the common sole Solea solea in the waters off the Moroccan Atlantic coast. Monthly samples were obtained from commercial bottom trawl fishing operations in the Safi fishing area, from January to December 2022. A total of 847 specimens were examined, ranging from 13 to 33 cm total length. The length-weight relationships were determined as W= 0.0097 L3.012 for females and W= 0.01089 L2.969 for males. The von Bertalanffy formula was applied to estimate growth parameters, revealing L∞, K, and t0 values for males (L∞=23.98 cm, K= 0.945 year−1, t0=-0.001 years) and females (L∞=23.71 cm, K= 0.884 year−1, t0=-0.002 years). The estimated age ranged from 0 to 8 years. The total mortality (Z), natural (M) and fishing mortality (F) rates were estimated as Z=4.48, M=1.84 and F=2.64 respectively. The estimated exploitation rate (E=0.59), indicated overexploitation of S. solea in the studied fishing area. Based on these results, it is essential to formulate sustainable management strategies to safeguard this marine resource and support the development of fishery plans. Keywords: Exploitation rate, Growth, Management strategy, Mortality, Safi fishing
Preservation of yellowfin tuna (Thunnus albacares) chunks using edible wraps prepared from under-utilised Averrhoa bilimbi fruit juice, infused with chitosan and fish gelatin
The study aimed to investigate the bioactive properties of Averrhoa bilimbi fruit juice, focusing on its antioxidant and antimicrobial activities, and to evaluate its use as edible wraps infused with chitosan and fish gelatin for preserving tuna chunks under chilled conditions (4 °C). The wrap comprised A. bilimbi fruit juice (BJW 50% and BJW 100%) blended with fish gelatin (5%) and chitosan (0.5%). Antioxidant activity increased in a concentration-dependent manner and was positively correlated with the phenolic content of bilimbi juice. In the disc diffusion antimicrobial assay, 100% BJW showed the largest zone of inhibition against Lysteria monocytogenes (24.70±0.01 mm). During refrigerated storage, the psychrophilic bacterial counts in the control, GCW (gelatin-chitosan wrap), and BJW 50% wraps exceeded the acceptable limit of 7 log CFU g-1 by the 12th day of storage. In contrast, the samples wrapped with the BJW 100% remained within the acceptable limits until the 15th day, which corresponded well with the results of the antimicrobial assay, demonstrating the preservative potential of BJW. Similar trends were observed for lipid oxidation and spoilage indicators, Thiobarbituric acid reactive substances (TBARS) and total volatile base nitrogen (TVB-N) values, of the control, GCW, and BJW 50% samples exceeded permissible limits on the 6th day of storage, while BJW 100% treated samples exceeded the limits only after the 15th day. Overall, A. bilimbi juice-based edible wraps effectively maintained the microbiological and biochemical quality of tuna chunks, demonstrating their potential as a safe and effective biopreservative for seafood applications. Keywords: Antioxidant properties, Antimicrobial assay, Chilled storage, Phenolic content, TBARS, TVB-N
Copyright (c) 2025 Indian Journal of Fisheries https://creativecommons.org/licenses/by-nd/4.0
Taxonomic assessment and diversity of sea slugs (Gastropoda: Heterobranchia) along the Karnataka Coast, India
Sea slugs in Karnataka's marine ecosystems have been understudied, resulting in limited documentation. To address this gap, extensive field surveys were conducted across the rocky reefs and off-shore patchy reefs of Karnataka, extending up to a depth of 38 m. During the surveys nine sea slug species were documented, representing four genera (Goniobranchus, Phyllidia, Coryphellina, and Elysia), belonging to four families (Chromodorididae, Phyllidiidae, Flabellinidae, and Plakobranchidae). Six of the nine species recorded are new additions to the sea slug fauna of the Karnataka Coast. By combining data from the current surveys with historical records, an annotated checklist of 36 species of sea slugs found in Karnataka was compiled. Keywords: Annotated checklist, Rocky reefs, Marine ecosystems, Patchy reefs
First successful trial of seaweed (Kappaphycus alvarezii) cultivation in Karnataka, India
This study highlights the successful raft-based cultivation of Kappaphycus alvarezii in the Yadamavinahole Estuary, Uppunda, Karnataka over a period of 72 days during pre-monsoon season (February to April, 2025). A total of 20 net tubes were deployed, yielding 180 kg of fresh biomass and the mean biomass per tube was 8.94 ± 0.10 kg. The growth performance was promising with a specific growth rate of 2.06±0.04% day⁻¹ and a daily growth rate of 2.16 ± 0.03% day⁻¹. Optimal water quality conditions supported consistent growth. The trial success underscores the potential for scalable seaweed farming in the region and provides essential insights for enhancing future commercial cultivation practices. Keywords: Blue economy, Coastal communities, Commercial cultivation, Livelihoods
Seaweed, Kappaphycus alvarezii, Karnataka
Biological parameters of the revalidated cyprinid Osteobrama dayi, endemic to the Godavari River, India
The length-weight relationship is of great importance in fishery assessments. In the present study, we estimated the length-weight relationship (LWR) of a recently re-validated endemic cyprinid, Osteobrama dayi, which is endemic to the Godavari River. The specimens were collected from their natural habitat between 2021 and 2023. The “b” value ranged from 3.29 to 3.50 between pre-monsoon and monsoon season, whereas the “a” value ranged between (-)2.25 and (-)2.53, respectively. This study provides the first report on LWR for O. dayi and records the maximum standard length (26.4 cm) and total weight (728 g), recorded for this species from the wild, along with the condition factor (K). The baseline information on LWR and K for O. dayi will be useful in further studies on the stock management of this endemic species. Keywords: Conservation, Condition factor, Cyprinid, Endemic species, Length-weight relationship, Health status
Range extension of the red-tipped halfbeak Hyporhamphus xanthopterus (Valenciennes, 1847) in the Cauvery River, Western Ghats of India: Integrative taxonomy and resolution of taxonomic misidentifications
This study reports a noteworthy range extension of the freshwater halfbeak Hyporhamphus xanthopterus (Valenciennes, 1847) from the Western Ghats of India, with the first confirmed record from the Cauvery River in Tamil Nadu. This discovery significantly expands the known distribution of the species within Indian freshwater ecosystems. This study presents the first molecular validation of H. xanthopterus from Indian waters, integrating mitochondrial DNA data with detailed morphometric and meristic analyses. The findings contribute to resolving taxonomic ambiguities within the genus Hyporhamphus, provide refined diagnostic criteria for accurate species identification and offer new insights into the biogeographical distribution of this poorly understood taxon. These results establish a valuable baseline for future taxonomic, phylogenetic and conservation-oriented research on freshwater halfbeaks in South Asia. Keywords: Cauvery River, Freshwater ecosystems, Meristic counts, Mitochondrial CO1, Molecular validation, Morphometry
Halfbeak, Freshwater, Vulnerable , Cytochrome oxidase I, Conservation
Fisheries Cooperative Governance Quality Index: A novel methodology for assessing primary fisheries cooperative societies
The governance of cooperative societies is an important facet as it indicates success or failure for any cooperative society. The present study was conducted in the purposively selected Pune District of Maharashtra State with randomly selected 41 Primary Inland Fisheries Cooperative Societies (PIFCSs) for assessing quality of governance using novel Fisheries Cooperative Governance Quality Index (FCGQI). The study found that the majority (51.22%) of PIFCSs had medium governance quality scores (0.56-0.70), followed by 34.15% of PIFCSs showing low (<0.55) level of governance quality. The governance quality in PIFCSs perceived by the executive body (0.57) and the general body (0.55) members was found closely aligned. There were significant opinion differences among the executive body (0.47) and the general body (0.40) members about the quality of leadership in IPFCSs. The quality of governance in selected fisheries cooperatives positively correlated with younger leadership, trained executive body members, availability of basic infrastructure, greater interactions with other organizations and higher levels of women empowerment. The regression model with selected independent factors found best fit (R2=0.78). Ensuring regular staff, basic infrastructure, diversified income generating activities, enhancing women and youth participation, along with building leadership capacity and stronger collaborations with research and development institutions would strengthen fisheries cooperatives and sustain member’s livelihoods. Keywords: Inland fisheries, Leadership, Livelihood, Teaming, Women empowerment
Development of a scale to measure the perception of stakeholders towards marine fisheries governance: A methodological approach from a case study in Andhra Pradesh
This study aims at development of a psychological scale to measure the perception of stakeholders towards the Andhra Pradesh Marine Fisheries Regulation Act (APMFRA). The collection of items included 31 statements covering the dimensions such as zonation, registration, licensing, monitoring, implementation, conservation related fishing regulations, penalty structures and effectiveness. The 31 statements were evaluated by a group of 34 judges representing research, education and extension in the field of fisheries and social sciences, through which 18 statements were selected with relevancy percentage of more than 61 %, and mean relevancy score of more than 1.85. Through t-test item analysis, the final perception scale was constructed with 10 statements with t value of more than 1.75, out of the 18 statements. The scale has demonstrated both reliability and validity, confirming its consistency and accuracy in measuring perceptions of APMFRA. The administration of the scale among the stakeholders would elicit their perception towards the Act, and the areas to be strengthened for effective fisheries governance such as the regulations which are to be strengthened with the incorporation of scientific advisories, technological measures and conflict resolution mechanisms. Keywords: APMFRA, Attitude, Fishing regulations, Governance, Psychological scale
Attitude, perception, governance, marine fisheries, APMFRA, stakeholders, perception scale
Optimisation of retort process parameters and evaluation of heat penetration characteristics of the traditional shrimp dish, Iral kootu
The main objective of this study was to optimise the retort process parameters and evaluate the heat penetration characteristics at the optimised time-temperature for the shrimp dish Iral kootu. Three varieties of shrimps were used for the study: White (Penaeus indicus), Tiger (Penaeus monodon) and Flower shrimp (Penaeus semisulcatus). The dishes were prepared and packed in retort pouches and processed to different time-temperature combinations. Preliminary optimisation was done for processing temperatures of 115 and 121°C for 5, 10 and 15 min. Based on sensory evaluation, 115 and 121°C for 10 min were selected for further optimisation. Commercial sterility tests and sensory evaluations of the products from the second trial indicated that both products are commercially sterile, but the product processed at 121°C for 10 min secured a higher sensory score for all the attributes. Heat penetration characteristics were determined using Ball’s graphical and mathematical methods, at 121°C for 10 min. The estimated total process time (B) was 36 min, with a corresponding lethality value (F0) of 8.89 min and a cook value (C) of 59.35 min. Keywords: Cook value, Commercial sterility, Penaeus indicus, Penaeus monodon, Penaeus semisulcatus, Sensory evaluation
Iral Kootu; optimization; commercial sterility, sensory evaluation; heat penetration characteristics
Antibacterial activity of green-synthesised silver nanoparticles (AgNPs) on major bacterial fish pathogens with emphasis on their extracellular enzymatic and haemolytic activities
Silver nanoparticles (AgNPs) were synthesised using a green synthesis approach using silver nitrate, starch and glucose under optimised conditions. Morphometric characterisation of the green-synthesised AgNPs was carried out by Fourier-transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), dynamic light scattering (DLS), and X-ray diffraction (XRD). The antibacterial, extracellular enzymatic and haemolytic activities of AgNPs were evaluated against nine fish pathogenic bacteria, viz., Aeromonas hydrophila (AH1), Edwardsiella tarda (ATCC15947), Pseudomonas putida (ATCC49128), Pseudomonas aeruginosa (ATCC35072), Pseudomonas fluorescens (PF1), Vibrio alginolyticus (ATCC17749), Vibrio parahaemolyticus (ATCC17802), Escherichia coli (EC1) and Staphylococcus aureus (ATCC6538). Bactericidal activity of AgNPs was assessed using both minimum inhibitory concentration (MIC) and disc diffusion assays. In A. hydrophila, starch hydrolysis was completely inhibited from 72 h onwards in cultures exposed to both 50 μl and 100 μl of AgNPs. Similarly, the haemolytic activity of V. alginolyticus showed a marked reduction from 24 h onwards at both AgNP exposure levels (50 μl and 100 μl). Bacterial sensitivity to AgNPs was found to vary among species, indicating pathogen-specific responses to AgNP treatment. Keywords: Antibacterial activity, Bacterial sensitivity, Minimum inhibitory concentration, Nanomaterials in aquaculture, Virulence factors
Antimicrobial, extracellular enzyme, fish pathogens, silver nanoparticles
Molecular characterisation of the IRAK1 gene and its expression analysis in the Indian catfish Clarias magur, following Aeromonas hydrophila infection challenge
Interleukin-1 receptor associated kinase 1 (IRAK1) is a crucial downstream signaling mediator of the Interleukin-1 (IL-1) and Toll-like receptor (TLR) signal transduction pathways, responsible for sensing invading pathogens or endogenous danger signals and initiating appropriate immune responses. In this study, the partial cDNA sequence of IRAK1 gene was amplified, cloned, characterised and its modulation in response to Aeromonas hydrophila infection was studied in the Indian catfish Clarias magur, a promising fish species for aquaculture in the Indian subcontinent. The magur IRAK1 (mIRAK1) cDNA sequence of 590 bp was obtained by cloning and was found to encode a putative protein of 196 amino acid residues. This protein contains a serine/threonine kinase catalytic domain (STKcD) with activation sites responsible for kinase activity having a calculated isoelectric point (pI) of 6.65 and molecular weight of 21.68 kDa. Phylogenetically, mIRAK1 clustered together well with other members of the catfish family and showed the highest identity with pangasius catfish. Presence of highly conserved elements, including a conserved STKcD domain and cycline-dependent kinase 1 (CDK1) motif, were revealed by multiple sequence alignments in mIRAK1. Basal expression analysis indicated that mIRAK1 was widely expressed in all examined tissues, with the lowest expression in muscle and the highest in liver. Following A. hydrophila infection challenge, mIRAK1 expression was significantly up-regulated in vital immunological organs such as kidney, spleen, intestine and liver at 3 to 24 h post-infection. These results emphasise the critical role of mIRAK1 in host defence mediated by TLR and IL-1 signalling pathways during A. hydrophila infection. Keywords: Basal expression, cDNA sequence, Immune gene expression, TLR and IL-1 signalling pathways
Recombinant expression of soluble gonad inhibiting hormone (GIH) from Penaeus monodon in a bacterial expression system
Successful reproduction of captive shrimp has been the primary goal of commercial breeding program. Gonad inhibiting hormone (GIH), a member of CMG neuropeptide hormone family present within the neural tissue of the eyestalk of crustaceans, exert profound influence on reproductive maturation in shrimps. Present study reports the recombinant expression and purification of the GIH gene, using an Escherichia coli expression system. This is the first report of expressing the recombinant GIH of P. monodon using E. coli expression system in its native soluble form secreted to the media. The purified recombinant peptide is useful in structure and function analysis, which can be used for identifying its interacting partners and elucidating its mode of action. Production of an antibody/antagonist for the GIH would facilitate the development of an immunological tool for induced maturation in shrimp industry. This procedure could replace the physiologically destructive eyestalk ablation technique. Keywords: Escherichia coli expression system, Eyestalk ablation, Immunological tool, Recombinant GIH protein
Penaeus monodon, Gonad inhibiting hormone, recombinant GIH protein, eyestalk ablation, Escherichia coli expression system
Mitochondrial DNA insights into population structure for sustainable management of hilsa fishery
The rapidly declining populations of the Indian hilsa shad Tenualosa ilisha (Hamilton, 1822), a commercially important species in India, necessitate detailed understanding of its population structure, which appears to be shaped by a balance between anadromous mixing and philopatric isolation. In this study, ATPase 8/6 and cyt b gene sequences of mitochondrial DNA were generated and analysed from seven populations of T. ilisha, sampled from Andhra Pradesh, Gujarat, Odisha, and West Bengal. The results revealed significant genetic differentiation among populations from various geographical regions. A total of 12 and 18 haplotypes were reported, with average haplotype diversities of 0.794 and 0.844, and nucleotide diversities of 0.004 and 0.003 for ATPase 8/6 and cyt b, respectively. High haplotype diversity, along with low nucleotide diversity, suggests that hilsa populations may have experienced recent population expansion or gene flow. Analysis of molecular variance (AMOVA) of the ATPase 8/6 dataset showed that 77.55% of the genetic variation was within populations, while 22.45% was among populations. For the cyt b dataset, 90.07% of the variation was found within populations, with only 9.93% variation among populations, indicating greater genetic homogeneity among populations based on the cyt b gene. Given that hilsa ascends rivers annually, there is a strong probability that philopatric migration has facilitated the accumulation of local genetic adaptations and the formation of distinct gene pools across different geographic regions. Therefore, hilsa populations from the northern and western parts of the Bay of Bengal and the Arabian Sea may require distinct restocking programs, fisheries management strategies, and conservation measures to address local genetic differences and to ensure the long-term sustainability of these populations. Keywords: Anadromous fish, ATPase 8/6, Mitochondrial DNA, Philopatry, Tenualosa ilisha.
Seasonal reproductive dynamics in common carp (Cyprinus carpio): Variations in gonadosomatic index and hormonal profiles
This study investigated the seasonal reproductive cycle and hormonal dynamics in common carp (Cyprinus carpio var. communis), emphasising variations in the gonadosomatic index (GSI) and gonadotropin hormones (GtH-I and GtH-II). GSI remained low from late summer to December and peaked in May, reaching 9.5±0.46 in males and 16.3±0.12 in females. GtH-I levels showed minimal fluctuations throughout the year and had no significant correlation with GSI. In contrast, GtH-II exhibited marked seasonal variations, peaking in May (1.26±0.03 IUl-1 in females and 0.36±0.15 IUl-1 in males), with a strong positive correlation with GSI (females: r = 0.91, males: r = 0.84). These findings highlight the pivotal role of GtH-II in regulating gonadal development and reproductive timing in common carp, providing insights into its endocrine control mechanisms. Keywords: Endocrine control, Gonadotropins,GSI, Reproductive cycle,Seasonal variation
Performance of tire track eel (Mastacembelus favus Hora, 1924) fry reared at different stocking densities in composite tanks
This study aimed to evaluate the rearing performance of Mastacembelus favus fry under three different stocking densities: 50, 75, and 100 individuals per cubic meter (ind. m⁻³). The experiment was conducted over a period of 180 days, from September 2022 to March 2023, using 0.5 m³ composite tanks in a completely randomised design with three replicates per treatment. The yolk sac-exhausted fry (1.08 g and 6.54 cm) were reared under the trial stocking densities and fed commercial pellet feed throughout the rearing period. A stocking density of 100 ind m⁻³ had a significantly adverse effect on most of the measured performance parameters, including mean weight, mean length, daily weight gain, daily length gain, survival rate, feed conversion ratio, and productivity (p<0.05). While most performance indicators did not differ significantly between the 50 and 75 ind m⁻³ treatments (p>0.05), productivity at 75 ind m⁻³ was significantly higher than at 50 ind m⁻³ (p<0.05). These findings suggest that a stocking density of 75 ind m⁻³ was optimal for rearing M. favus fry under the study conditions. Keywords: Environmental sustainability, Growth, Productivity, Survival rate, Vietnam
Genetic health of Indian major carps: Assessment of effective population size and rate of inbreeding in fish hatcheries of Tamil Nadu, South India
The present study evaluated the genetic health of hatchery populations of the Indian major carps (IMCs), catla Labeo (=Catla) catla), rohu Labeo rohita and mrigal Cirrhinus mrigala in Tamil Nadu, South India. The study was based on the data collected during the 2023-2024 breeding season from 16 private hatcheries and 3 government hatcheries in Tamil Nadu. The estimated effective population size (Nₑ) ranged from 13 to 640 for catla, 18 to 1015 for rohu and 9 to 474 for mrigal. Correspondingly, inbreeding rates varied from 0.08% to 3.89% in catla,0.05% to 2.75% in rohu, and 0.11% to 5.63% in mrigal, indicating varying levels of genetic risk among hatcheries. Effective ways to control and prevent further accumulation of inbreeding are discussed in this paper, in order to improve the genetic quality and long-term sustainability of captive seed production of IMCs. Keywords: Carp seed, Catla, Hypophysation techniques, Induced breeding, Rohu, Mrigal
Predicting native fish diversity in river Bharathapuzha: Non-linear responses to environmental drivers revealed by Generalised Additive Models
Predicting how biodiversity responds to environmental changes is crucial for effective conservation; however, the functional relationships underpinning diversity metrics often remain obscure. In this study, we developed a robust predictive model for Shannon diversity in fish in the Bharathapuzha River, Kerala, India, a system experiencing significant anthropogenic pressure. Utilising a comprehensive dataset (N=108), we applied Generalised Additive Models (GAMs) to predict Shannon diversity in native fish, a metric chosen for its sensitivity to community evenness in a system impacted by dominant invasive species. Our final model demonstrated an Adjusted R² of 0.171, a deviance explained by 20.7%, and was validated using 10-fold cross-validation (CV-R² = 0.138). Focusing on native species diversity, the model revealed a complex bimodal response to environmental drivers. Native fish diversity exhibited a significant nonlinear relationship with dissolved oxygen and nitrate, reflecting a fundamental longitudinal phase shift from sensitive upstream specialists to tolerant downstream generalists. These findings provide critical management insights; while habitat restoration offers direct, proportional gains in diversity, water quality management requires targeting specific ecological optima to maximise biodiversity benefits. This study underscores the utility of GAMs for developing mechanistically informative predictive models that are essential for guiding effective global river restoration and conservation. Keywords: Fish community, Bioassessment, GAM, Predictive modelling, Water quality
Fishery, growth, mortality and exploitation status of Daysciaena albida (Cuvier, 1830) from Vembanad Lake, a Ramsar site on the southwest coast of India
The fishery, growth, mortality and exploitation status of Bengal corvina Daysciaena albida were investigated from the Vembanad Lake, the largest brackish Ramsar wetland in southern India. D. albida ranks as the fourth important finfish species fished from the lake contributing 3.79% of the total fish production. Our study aimed to analyse the fishery and demographic pattern of D. albida to facilitate the formulation of fishery management options that enhance the livelihoods of artisanal fishermen. The estimated annual catch of D. albida from the Vembanad Lake was 10.84 t The length-weight relationship (LWR) was derived as W = 0.032 TL2.94 (r2 =0.98; SE=0.072). Growth parameters for the species were recorded as - asymptotic length (Lα) = 47.25 cm and growth coefficient (K) = 0.98 y−1. The natural mortality (M) was estimated at 0.83 y−1, and fishing mortality (F) was 1.13 y−1. The exploitation level (E) was calculated to be 0.58 which surpassed the optimum value (E50), indicating overfishing. To safeguard the species from depletion, it is imperative to put in place management strategies, such as regulating mesh sizes, establishing closed fishing seasons, reduction of fishing effort and enforcing catch quotas for fishers. Keywords: Bengal corvina, LWR, Management, Overexploitation, Small-scale fishery
Fishery and biological characteristics of the pearly hairtail Trichiurus auriga (Klunzinger, 1884) in the South-eastern Arabian Sea
The pearly hairtail Trichiurus auriga, a little-known deep-sea ribbonfish, has recently emerged as a commercially relevant resource in southern India due to expanding deep-sea trawling and increasing demand from the fishmeal and fish oil industry. Scientific information on its biology, growth and fishery characteristics remains scarce, limiting management interventions. This study presents the first comprehensive account of fishery trends, age, growth, and reproductive biology of T. auriga using specimens (n=895) collected from the Neendakara (Kerala), Colachel and Jeppiar (Tamil Nadu) landing centres between 2022–2024. Length and body weight ranged between 190–420 mm TL (total length) and 20.8–28.4 g respectively. Length–weight relationship (LWR) parameters indicated negative allometric growth (b = 2.88), though the deviation from isometry was not statistically significant (p>0.05). Sagittal otolith microstructure analysis revealed ages ranging from 107 to 267 days, with corresponding daily growth rates of 1.34–1.85 mm day⁻¹. Female fecundity ranged between 320 and 710 ova, and maturity indicators confirmed sexual maturity at or below 190 mm TL. Large-scale landings and frequent misidentification of T. auriga as juveniles of Trichiurus Lepturus, pose regulatory challenges, particularly in the enforcement of under minimum legal size (MLS) regulations. The findings of the study provide baseline biological information and highlight the need for species-specific identification and management strategies to ensure the sustainable exploitation of this emerging deep-sea fishery. Keywords: Deep-sea trawling, Fecundity, LWR, Maturity stages, MLS, Ribbonfish, Sagittal otolith
Trichiurus auriga, LWR, Sagittal otolith, Fecundity, maturity stages