Journal of Fisheries (University of Rajshahi)
Not a member yet
287 research outputs found
Sort by
Molecular characterization based on cytochrome C oxidase I gene of the family Channidae from different riverine systems of Odisha, India
Get PDFThis study focuses on four Channa species from the northern part of the Eastern Ghats in India: Channa punctata (Bloch, 1793); Channa striata (Bloch, 1793); Channa marulius (Hamilton, 1822) and Channa gachua (Hamilton, 1822). The aim is to determine whether their molecular divergence aligns with their morphological distinctiveness. The molecular analysis based on mitochondrial COI gene sequences revealed distinct clusters for each species and genus, with K2P distances ranging from 17.28 – 27.96%. Notably, C. marulius was positioned in a distinct clade separate from the C. punctata, C. striata, and C. gachua groups. Channa gachua clustered with Channa rara and Channa kelaartii, suggesting a close evolutionary relationship. Channa punctata and C. striata also clustered together, reinforcing their status as sister species. Species delimitation using the Assemble Species by Automatic Partitioning method identified 10 partitions, with the most reliable delimitation showing a clear separation of Channa species of Odisha. These findings align with recent analyses and confirm that the molecular divergence among the four species is consistent with their morphological differences. The study underscores the importance of molecular methods in resolving taxonomic ambiguities and understanding species diversity. It provides a foundational molecular database for Channa species, supporting future research on genetic divergence and contributing to conservation and aquaculture efforts
Assessment of biomonitoring potential of contamination and bioavailability of heavy metals using red blood cockle Tegillarca granosa: Experimental field-based transplantation study
Get PDFThis study evaluates the potential of red blood cockle Tegillarca granosa as a biomonitor for heavy metal contamination in coastal environments, with a focus on the differential bioaccumulation patterns across three sites: Teluk Kemang (TK), Pasir Panjang (PP), and Port Dickson (PD). Four major findings emerged from the analysis. First, T. granosa demonstrated significant variations in metal accumulation, with PD exhibiting the highest concentrations of Zinc (Zn), Copper (Cu), and Iron (Fe). This confirms the species' sensitivity to varying pollution levels and highlights PD as the most contaminated site among the three. Second, strong correlations between metal levels in the environment and their accumulation in the cockle’s soft tissues underscored its effectiveness in reflecting the bioavailability of contaminants, particularly for Zn and Cu. This finding validates the use of T. granosa as an effective bioindicator of environmental metal exposure. Third, the study highlighted the role of cockle shells as indicators of long-term exposure, with consistently higher metal concentrations observed at PD. This suggests persistent environmental contamination in this area and demonstrates the value of shell analysis in assessing chronic pollution. Finally, the stepwise multiple regression analysis revealed complex interactions between environmental media and bioaccumulation processes, emphasizing the need for a comprehensive approach to biomonitoring. These interactions indicate that bioaccumulation in T. granosa is influenced by multiple environmental factors, necessitating an integrated monitoring strategy. These findings support the use of T. granosa as a reliable indicator species for monitoring heavy metal pollution and assessing ecological risks in coastal ecosystems
Maiden study on fish diversity of the Diring River in Baksa District, Assam, India
Get PDFThe Northeast India has several natural water resources that support a variety of aquatic fauna. However, many parts of the region have remained unexplored for ichthyofauna. Research on the diversity of fishes in large water bodies has received significant attention from many researchers in the region. In contrast, studies on small stream rivers are very scant. Therefore, the present study aims to record the diversity of fish fauna in the small stream Diring River of Baksa District, Assam. In this survey, 27 species of fishes were recorded from five study sites. The dominant family was Cyprinidae, comprising 48% of the total fish species. The conservation status of the majority of species was Least Concern (88.8%) followed by Near Threatened (3.7%) and Vulnerable (3.7%). However, conservation status of 3.7% of the fish species was not evaluated by IUCN. The Shannon diversity index ranged from 1.5 to 2.6, the evenness index from 0.84 to 0.98, and the richness index from 1.1 to 2.6, indicating a good status of ichthyofaunal resources in the study sites. Since there were no existing records on the fish diversity of the Diring River, this maiden study might serve as baseline information for further research
First record of Telestes pleurobipunctatus (Stephanidis, 1939) in freshwater of Al-Bireh Dam, Wadi Al-Ayoun, Hama, Syria
Get PDFDespite a large number of studies on freshwater fish fauna in Syrian aquatic habitats lack of data exists for many. This study was conducted in Al-Bireh Dam, located in Wadi Al-Oyoun region, Hama Governorate of Syria and recorded Telestes pleurobipunctatus (Stephanidis, 1939) (Cyprinidae) for the first time. In April 2023, thirteen individuals of the species were caught using local fishing methods. The species is characterised by the presence of a dark band on the sides of the body extending from the front of the snout to the end of the caudal fin, and an orange spot at the base of the pectoral fin. This research sheds light on the qualitative composition of the fish fauna in Al-Bireh Dam Lake, as the species T. pleurobipunctatus is recorded for the first time in Syrian freshwaters
Zinc in commercial marine fish from Peninsular Malaysia: Biomonitoring, health risks, and UNSDGs’ connection
Get PDFThe present study aimed to determine the human health risk (HHR) of zinc (Zn) in forty species of marine commercial fishes sourced from Peninsular Malaysia and available between April and May 2023. These species exhibited concentrations of Zn ranging from 24.1 to 153 mg kg–1 dried weight. These values fell below the maximum allowable limits established by seafood safety guidelines, indicating that the fish are valuable sources of the essential element. The Zn target hazard quotient values were below 1, suggesting that consuming fish containing Zn poses no non-carcinogenic risks. Additionally, it was discovered that the computed estimated weekly Zn intake values were lower than the established provisional allowable weekly Zn intake. It can be inferred that ingesting fish from Peninsular Malaysia would not expose consumers to any detrimental consequences regarding Zn levels. Although this is true, on-going surveillance via Fish Watch (biomonitoring of metal pollution using fish) is imperative to safeguard the well-being of consumers who significantly depend on commercial marine fish imported from Peninsular Malaysia. The study contributes to the achievement of the United Nations Sustainable Development Goals, particularly Goal 3 (Good Health and Well-being) by promoting safe consumption, Goal 12 (Responsible Consumption and Production) through sustainable fishing practices, and Goal 14 (Life Below Water) by emphasizing the importance of protecting marine ecosystems
Stock assessment of rosy barb, Pethia conchonius (Hamilton, 1822) in Dal Lake of Kashmir Himalayas
Get PDFFor management of fish stocks, assessing the various parameters of population dynamics are regarded as being extremely important. Under this backdrop the population dynamics parameters viz. growth, mortality and recruitment of Pethia conchonius, inhabiting the Dal Lake of Kashmir Himalayas were analysed using FiSAT II software. The analysed specimens were collected from five different sites within the lake and exhibited a total weight range of 0.3 to 6.4 g and a total length range of 3.1 to 7.8 cm. The relative condition factor for the fish was reported to be 1.11. The growth parameter i.e., asymptotic length, age at zero length, growth performance index and growth constant were reported to be 10.0 cm, –0.75 years, 1.48 and 0.30 year–1 respectively. The total mortality of 1.49 year–1, consisting of natural mortality of 0.88 year–1 and fishing mortality of 0.61 year–1 was reported. An exploitation rate of 0.41 is suggestive of a less exploited state of the fish. The length at first maturity was found to be higher than the length at first capture, a condition that can disturb the stock, as such the utility of a net with relatively larger mesh size is advisable. The current research on the population dynamics of P. conchonius can be used as the baseline data for its management practices
Stock assessment of Nemipterus japonicus (Bloch, 1791) in Tha-Bawt-Seik coastal area, Dawei, Myanmar
Get PDFThe stock assessment of the threadfin beam, Nemipterus japonicus, collected from the Tha-Bawt-Seik of the Andaman Sea in Myanmar were analysed from January to December 2018. The purpose of this study is to evaluate the condition of the N. japonicus population. For all 1866 specimens, the asymptotic length (L∞), growth rate (K) and growth performance index (Ǿ) were 22.05 cm, 1.4 year–1 and 2.833 respectively. There were 4.89 year–1, 2.47 year–1 and 2.41 year–1 for the total mortality rate (Z), natural mortality rate (M) and fishing mortality rate (Z) respectively. The maximum exploitation rate (Emax) was 0.703, while the exploitation rate (Ecurrent) was 0.49. There were two main recruitment pulses in the pattern of continual recruitment. When the dry season began, threadfin beams became one of the principal species in Tha-Bawt-Seik. The outcomes of the study showed that while the N. japonicus stock is currently safe; there are signs of growth overfishing and any rise in the existing pace of exploitation is likely to exacerbate this issue
Temporal changes in glochidia larval occurrence and condition index in freshwater mussels, Lamellidens marginalis (Lamarck, 1819) collected from a wetland of Bangladesh
Get PDFInformation on glochidia larval occurrence and release time from the brooding mussels are crucial for the development of larval rearing system or commercial collection of juveniles from the wilds. We report monthly changes in glochidia larval occurrence and condition index (CI) in freshwater mussel, Lamellidens marginalis, collected from a wetland in Bangladesh. Specimens were drawn monthly over a year from October 2021 to September 2022. Lamellidens marginalis females displayed glochidia larvae in the supra-branchial chamber over ten months from March to December. No glochidia larva was reported in females during January and February when the water temperature remained below 18°C. All females carried glochidia larvae during March and April, indicating no larval shedding at this time. The percentage of females containing glochidia larvae dropped suddenly in May (22.22%), suggesting that glochidial release from the gill chamber to the environment was initiated by May. Larval presence in only some females (22% to 86%) at each sampling date from May to September implied an extended glochidial discharge period till September when the water temperature was above 24°C. The CIs varied from 0.36 to 0.79, with two distinct peaks in December and March when all females carried glochidia larvae. In conclusion, monthly changes in larval occurrence and discharge could be primarily related to temperature and the existence of larvae in mussels could affect the CIs in L. marginalis
Bioaccumulation of iron (Fe) and lead (Pb) in various body tissues of Telescopium telescopium in Peninsular Malaysia: Implications for biomonitoring and sustainability
Get PDFHeavy metal contamination in marine environments poses a significant threat to aquatic ecosystems and human health. This study investigates the accumulation patterns of iron (Fe) and lead (Pb) in seven different body tissues (cephalic tentacle [CT], digestive caecum, foot, gill, mantle, muscle, and remaining soft tissues) of Telescopium telescopium collected from Peninsular Malaysia. Using heat map visualization and correlation analysis, we examined the relationships between Fe and Pb levels in various body tissues. High positive correlations were observed in Fe levels between the foot- CT (r = 0.86), and Pb levels between the muscle and CT (r = 0.95). Factor analysis highlighted the complex interplay of environmental and physiological factors influencing metal accumulation. Our findings underscore the importance of considering multiple tissues for accurate biomonitoring of metal pollution in marine environments, particularly in the context of sustainability and, environment, social and governance considerations
Impacts of flooding on rural communities in Bangladesh
Get PDFFlooding is a regular phenomenon in many countries, including Bangladesh, causing severe damage to communities. Despite widespread impacts, most studies focus on a single community. This study examines the impacts of flooding on three key rural Bangladeshi communities: agriculture farmers, fish farmers, and fishermen. Data were collected from three flood-prone areas: Roumari Upazila (Kurigram district), Chauhali Upazila (Sirajganj district), and Char Bhadrasan Upazila (Faridpur district). The mean age of respondents varied across groups (LMM: F = 21.2, p < 0.001), but not across study sites. The mean education level was 6.9 ± 4.9 years, with fish farmers having the highest schooling at 7.4 years. Monthly income varied across groups (LMM: F = 174.3, p < 0.05). Most respondents (84.7%) received financial loans from non-government sources. Flooding negatively affected agricultural and fish farmers, who lost their crops. However, fishermen experienced a positive effect, with increased fishing days and duration, leading to higher fish harvests during floods (LMM: all p < 0.05). The study also highlights respondents’ expectations to minimize flood impacts. The findings of this study are crucial for understanding the variation in flood impacts on key communities in rural Bangladesh and can inform effective flood management planning