Loading...
Thesis
Browse
57 results
Search Results
ThesisItem Open Access Comparative Studies on Biodiversity and Ecopath Modeling of Closed and Open Beels of Assam(West Bengal University of Animal & Fishery Sciences, Kolkata, 2021) Gogoi, Rinku; Behera, S.; Borah, B. C.; Das, Sudhir Kumar; Nagesh, T.S.; Chand, B.K.The Study was conducted in the Borsola (Open) and Potiasola (Closed) beels of Jorhat District of Assam from June 2015 to January 2017 to assess the biodiversity and trophic status of the lakes by using ECOPATH model. A total of 38 finfish species and two shellfish species (one prawn and one mollusc) were recorded from the Borsola beel and a total of 34 finfish species and two shellfish species were recorded from the Potiasola beel during the study. Among the finfish, families encountered Cyprinidae dominated with 42% of the total species recorded followed by Bagridae (8%), Channidae (8%), Siluridae (5%), Mastacembelidae (5%) and Notopteridae (5%) in Borsola beel, whereas Cyprinidae dominated with 38% of the total species recorded followed by Channidae (9%), Bagridae (6%), Siluridae (6%), Osphornemidae (6%) and Mastacembelidae (6%) in Potiasola beel. A total of 26 phytoplankton species were identified at Borsola beel from all four sites throughout the study period belonging to seven groups of phytoplankton and a total of 22 phytoplankton species were identified at Potiasola beel from all the three sites throughout the study period belonging to six groups. Among the various groups of phytoplankton of Borsola beel, the population density of Chlorophyceae (31.92%) was the highest throughout the study period, which was followed by Zygnematophyceae (27.08%), Cyanophyceae (23.44%), Bacillariophyceae (6.69%), Euglenophyceae (6.44%), Nostocaceae (4.44%) and Ulvophyceae (1.84%). Whereas, in case of Potiasola beel, the population density of Zygnematophyceae (32.86%) was found to be the highest followed by Chlorophyceae (32.85%), Cyanophyeceae (14.30%), Euglenophyceae (12.11%), Bacillariophyceae (4.87%) and Trebouxiphyceae (3.01%). A total of 16 zooplankton species were identified at Borsola beel from all four sites throughout the study period belonging to four groups of zooplankton. Whereas, a total of 13 zooplankton species were identified at Potiasola beel from all the three sites throughout the study period belonging to six groups. Among the various groups of zooplankton of Borsola beel, the population density of Cladocera (49.57%) was the highest throughout the study period, which was followed by Copepoda (38.13%), Crustacea (11.13%) and Gastropoda (1.17%). Whereas, in case of Potiasola beel, the population density of Cladocera (44.72%) was found to be the highest followed by Copepoda (30.29%), Crustacea (11.64%), Decapoda (5.14%), water mites (4.75%) and Protozoa (3.46%). During the study period, a total of 28 species of macrophytes were recorded from the Borsola beel, whereas, a total of 25 macrophyte species were recorded from the Potiasola beel. In case of Borsola beel emergent species contribute (36%) to the total macrophytes followed by marginal (25%), submerged (21%) and floating type (18%), while in case of Potiasola beel emergent species contribute (40%) to the total macrophytes followed by submerged (28%) and floating (20%) and marginal (12%), respectively. During the study period, a total of 19 species belonging to 10 families of water birds were recorded from the Borsola beel. Whereas, a total of 13 water bird species belonging to 6 families were recorded from the Potiasola beel. From the above study, it was found that the Borsola (open) beel is richer in biodiversity than that of the Potiasola (closed) beel because of entrance of the different species from the adjoining beel and the River Brahmaputra. All physicochemical parameters of water (water temperature, pH, transparency, electrical conductivity, total dissolved solids, dissolved oxygen, total hardness, total alkalinity) studied i.e. were within the normal range in both the beels. Soil parameters (pH and organic carbon) were also recorded in the productive range in both the beels. Ecopath with ecosim analysis revealed that all indices (Total primary production/total respiration (TPP/TR), Finn’s Cycling Index (FCI), System omnivory index (SOI), Connectance Index (CI), Ascendency and Overhead Index) indicated that both the wetland ecosystems are ‘immature’, making it more fragile and susceptible for possible disturbances. This indicates that the primary production can support much more herbivore fauna than the present one. The study confirms that both the Borsola and Potiasola beels need immediate attention for their conservation and measures should be taken on urgent basis in order to intercepting the increasing trend of eutrophication and restoration of water quality and integrated management of the oxbow lake ecosystems. Species enhancement, cage culture (particularly in Borsola beel), pen culture and developing a comprehensive and sustainable management policies involving Government Officials are the need of the hour not only to enhance the fish production but also to maintain the ecological integrity of both the wetlandsThesisItem Open Access MOLECULAR TAXONOMY, BIOLOGY AND STOCK ASSESSMENT OF ARIUS JELLA DAY, 1877 OF WEST BENGAL COAST(West Bengal University of Animal & Fishery Sciences, Kolkata, 2022) Canciya, J; Nagesh, T.S.; Mahapatra, B.K.; Das, Sudhir Kumar; Behera, S.; Abraham, T.J.; Das, S.K.The present study was undertaken to study morphometry, DNA barcoding, length-weight relationship, food and feeding habits, reproductive biology and stock assessment of Arius jella Day, 1877, commonly known as Blackfin sea catfish. A total of 908 samples with a size range of 52-257 mm total length and 2.1-184.6 g total weight were collected and studied from February 2021 to July 2022 (except the fishing ban period of the West Bengal coastal water) on monthly basis in the coastal water of West Bengal, India. Analysis of 21 morphometric characters in A. jella revealed that standard length has the highest growth rate increment in relation with the total length (R2= 0.943; p<0.01). Among the meristic characters, fin formula of A. jella occurring in West Bengal coast could be written as: D.1/7, P.1/9-10, V. 6, A. 14-16, C. 15-21. DNA barcoding of A. jella cytochrome oxidase subunit 1 (COI) gene was done and submitted to the NCBI (Acc. No. OP315319). The length-weight relationship for the species is estimated as W = 0.000025L3.252 from the pooled samples and ‘t’ test indicated that the species exhibited positive allometric growth. The gut content analysis of A. jella revealed that the species is highly carnivorous in nature, mainly feeding on crustaceans and molluscs. The mean gastrosomatic index (GaSI) value for both the sexes fluctuated from the minimum (3.971± 1.10) in March 2021 to the maximum (7.772± 1.25) in August 2021. The total length at which 50% of the species attained maturity was estimated to be 144 mm and 158 mm for males and females, respectively. The gonadosomatic index (GSI) of A.jella showed that the fish matured throughout the year with two peak recruitments, a major spawning peak occurring in March to April and a minor peak in October to November. The month wise distribution of sex ratio indicated the marginal dominance of males over females except in the months of February, April, June and November. The male to female sex ratio was 1:0.9. The absolute fecundity ranged from 20 to 68 ova/individual. The relative fecundity of the fish ranged from 0.125 to 0.22 ova/body weight of female fish. The growth parameters found to be L∞ = 307 mm, K = 0.78 year-1, t0 = 0.0862 year. The growth performance index (Φ′) was 2.88. The lifespan (tmax) for this population was estimated at 4.17 years and the value of optimum catchable length (Lopt) was found at 186.4 mm. In addition, the total mortality (Z), natural mortality (M) and fishing mortality (F) rates were estimated at 3.61, 1.42 and 2.19 yr-1respectively, and exploitation ratio (E) was 0.61. The maximum exploitation (Emax) rate was obtained as 0.586 from the relative yield per recruit (Y/R) study and it is lower than the estimated E (0.61) value. Estimates of the reference points (MSY and fMSY) from present study considerably indicated fishing pressure for marine catfish in the study area exploitation has reached the maximum sustainable yield (MSY) level. The level of exploitation increasing from the current fishing pressure is not advisable for stock replenishment and its sustainability.ThesisItem Open Access ICHTHYOFAUNAL DIVERSITY AND ECOLOGICAL STATUS OF BANSABATI BEEL, MURSHIDABAD DISTRICT, WEST BENGAL(2023) Mondal, Argya Kamal; Srinivasan, Nagesh T.; Bhakta, Dibkar; Das, Sudhir Kumar; Behera, Samarendra; Abrahanm, T. J; Das, Bipul KumarThe research was carried out in an open wetland called Bansabati beel in the Murshidabad district of West Bengal from December 2020 to November 2021 to evaluate the fish diversity pattern, ecological status, trophic condition and fish-based Index of Biotic Integrity (IBI). Knowledge of fundamental aspects of ichthyofaunal diversity and eco-fishery status is essential not only to maintain a healthy aquatic ecosystem but also to develop effective management and conservation strategies. Fishes were sampled on monthly basis to study species composition, abundance, trophic guild and diversity. Fish diversity was analysed using diversity indices such as species richness index, Simpson’s diversity index, Shannon- Wiener’s diversity Index and Pielou’s evenness index. A total of 42 fish species belonging to 21 families were recorded with the Cyprinidae family contributing the most. The beel has a great deal of promise in the native and ornamental fish trade owing to their rich diversity. Carnivorous fish species dominated the trophic guild, followed by planktivores. One fish species was found to be ‘Endangered’, three fish species were found to be ‘Vulnerable’ and three fish species were found to be ‘Near Threatened’ categories of IUCN Red List. Various diversity indices revealed that the beel has moderate to high fish diversity and evenness. The impact of anthropogenic stress on fish assemblage integrity, the index of biotic integrity (IBI), was assessed utilizing the fish community structure with 12 metrics. Traditional IBI scores (5-3-1) showed that the ‘reference site’ had a high fish assemblage and the highest integrity compared to other sites. With an average IBI score of 43.33, the Bansabati beel could be categorized as ‘marginally impaired’. The study demonstrates that fish assemblage might serve as potential indicators of anthropogenic stress and its effect. Monthly analysis of physico-chemical parameters of water and soil revealed that all parameters studied were well within the tolerable limits of freshwater fishes. Overall mean value of Carlson’s trophic state index (53.85) of the Bansabati beel suggested that floodplain wetland may be classified to be in the ‘transition phase’ from ‘mesotrophy to eutrophy’. Among the various groups of phytoplankton, Chlorophyceae was the most dominant followed by Cyanophyceae, Bacillariophyceae and Euglenophyceae. During the study period, a total of eight species of macrophytes were recorded. The study suggested protecting the habitat by limiting the amount of human interference, scientific intervention and involvement of stakeholders in order to maintain diversity and to get sustainable ecological benefits from it.ThesisItem Open Access STUDY ON BIOCHEMICAL AND TEXTURAL PROPERTIES OF SURIMI AND SURIMI BASED PRODUCT FROM SUTCHI CAT FISH (Pangasianodon hypophthalmus, Sauvage, 1878)(Kolkata, 2017) Chatterjee, Dipankar; Chowdhury, Dr. S.; Ghosh, Dr. S.; Dora, Prof. K.C.; Das, Prof. B. K.; Sahu, Prof. S.ThesisItem Open Access IMPACT OF PERIODICAL FEED RESTRICTION ON GROWTH OF FINGERLINGS OF Anabas testudineus (BLOCH, 1792) WITH DIFFERENT PROTOCOLS(Kolkata, 2017) Mandal, Abhrajyoti; Das, Prof. S. K.; Mukhopadhyay, Dr. D. P.; Behera, Prof. S.; Nagesh, Prof. T. S.; Rout, Prof. S. K.; Talwar, Prof. N. A.ThesisItem Open Access Studies on Natural breeding and embroyonic deveiopment of an indigenous ornametal fish trichogaster lalius (hamilton, 1882) in acptive condition(Kolkata, 2017) Saha, Shibam; Behera, Prof. S.; Kumar, Dr. S. Munil; Das, Prof. S. K.; Nagesh, Prof. T. S.; Ghosh, Prof. T. K.; Mondal, Dr. A.ThesisItem Open Access STOCK STRUCTURE ANALYSIS OF Clupisoma garua (Hamilton, 1822) ALONG THE MIDDLE AND LOWER STRETCHES OF GANGA RIVERINE SYSTEM USING TRUSS NETWORK ANALYSIS AND OTOLITH MORPHOMETRY(Kolkata, 2016) Biswas, IPSITA; Nagesh, Dr. T. S.; Mukhopadhyay, Dr. P. K.; Das, Prof. S. K.; Behera, Dr. S.; Abraham, Prof. T.J.; Talwar, Dr. N. A.; A.M., Dr. SajinaThesisItem Open Access STOCK STRUCTURE ANALYSIS OF Clupisoma garua (Hamilton, 1822) ALONG THE MIDDLE AND LOWER STRETCHES OF GANGA RIVERINE SYSTEM USING TRUSS NETWORK ANALYSIS AND OTOLITH MORPHOMETRY(Kolkata, 2016) BISWAS, IPSITA; Nagesh, Dr. T. S.; Mukhopadhyay, Dr. P. K.; Das, Prof. S. K.; Behera, Dr. S.; Abraham, Prof. T.J; Talwar, Dr. N. A.; A. M., Dr. SajinaThesisItem Open Access BIOMETRICS AND ECOLOGY OF CIRRHINUS MRIGALA (HAMILTON) OF PANCHASAYAR WATERBODY.(Kolkata, 2007) Iangrai, Babetjanai; Behera, Dr. S.; Hazra, Anshuman; Das, Dr. S. K.; Nagesh, Dr. T.S.; Das, Dr. G.; Chattopadhyay, Dr. N. R.
