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The present study assessed the diet characteristics, trophic guild structure, and microplastics (MPs) ingestion by a group of fish sourced from the tidal creeks of the Mumbai coast along the Eastern Arabian Sea. The diet patterns were characterized using gastro-somatic index (GaSI), relative length of gut (RGL), diet overlap (α), diet breadth (B i ), and relative abundance of food items (%IOP), with a special emphasis on MPs contamination. The findings revealed that teleost and shrimps are the most preferred food items for these species. Whereas MPs contribute 5.50% of the total diet composition of the selected fishes. Additionally, we tried to find out the influence of fish size and dietary attributes on MP ingestion, identifying trophic level as a significant factor influencing contamination levels. Using the Polymer Hazard Index (PHI), the potential risks posed by MPs in fish samples were assessed, revealing notable discrepancies among polymers. For instance, polyvinyl chloride showed the highest PHI score of 198.75 and a hazard score reaching the highest risk category (IV), indicating substantial environmental risk. In summary, our findings highlight the impact of fish diet characteristics on MPs contamination and the varying levels of MP risks along the Mumbai coast, categorized according to polymer type from low to high risk., Competing Interests: Declaration of Competing interest The authors declare no competing interests., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Backgroud: The Northeast India, being part of two global biodiversity hotspot namely the Indo-Burma and Eastern Himalayan Hotspots supports a wide variety of rich aquatic biodiversity including fishes. The family Danionidae is a widely diverse group inhabiting the upper colder stretches of river although few are abundant in the lower stretches. The persisting similarity in the morphological appearance and body colouration within the members of this family seeks an integrated method to identify the species correctly., Methods and Results: In the present study, the mt-DNA barcode was generated for correct identification and confirmation of the species. A total of nine mitochondrial cytochrome c oxidase subunit I gene sequences were generated for each species under the study. The pairwise distance values ranged from 0.09 to 9.11% within species and 9.06-32.71% between species. A neighbour-joining tree was constructed based on the Kimura 2 parameter model. Two major groups were observed where Danioninae formed a sister group to the Chedrinae and Rasborinae., Conclusion: The present study is a preliminary work to document and identify the species under the family Danionidae from Brahmaputra basin, Assam, using molecular tools and establish the phylogenetic relationship., (© 2024. The Author(s), under exclusive licence to Springer Nature B.V.)

The present study assessed the trophic status of a medium-sized microtidal estuary, Rushikulya, India using a combination of mutimetric trophic indices (TRIX, TRBIX) and a machine learning approach (Random Forest). A total of 108 samples were considered to build a predictive model for chlorophyll a (Chl a) and 17 response water variables by observing two annual periods (2021-2023) at six sampling sites. Mean values of TRIX (5.04 ± 0.72) and TRBIX (0.17 ± 0.08) reflected that the estuary has a moderate degree of eutrophication with 'good' water quality and 'biomass saturated'. However, the threshold of TRIX represents a transition state from 'moderate' to 'high' eutrophic. Random Forest model reflected that no apparent association between Chl a and water turbidity above 30 NTU and eutrophication in the estuary fluctuated mainly due to PO 4 3- -P along with electrical conductivity. Linear statistical correlations showed high correlation between Chl a and conductivity and a negative correlation between Chl a and dissolved oxygen, unlike PO 4 3- -P., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Fish of the genus Hypselobarbus (Bleeker 1860) are widely dispersed in the rivers of the Western Ghats in India and endemic to southern Indian peninsular freshwaters. These are small- to medium-sized fishes of the family Cyprinidae. Although fish with deformed bodies or body parts are rare in natural waters, this article deals with four abnormal specimens of Hypselobarbus curmuca (Hamilton 1807) collected from the rivers Tunga, Bhadra, and Kali during 2022. The abnormalities observed in four different individuals are pughead deformity, pelvic fin deformity, pectoral fin deformity, and enlarged scales. The morphological comparison of normal individuals of Hypselobarbus curmuca (Hamilton 1807) with abnormal specimens revealed variation. Using the MT-COI gene, species identity was confirmed and the mean genetic divergence between the normal and abnormal specimens was estimated to be less than 1%.

Identifying the breeding grounds of fishes is crucial for the sustainable management of fisheries resources. The present study is aimed at identifying the potential breeding ground of Mugil cephalus along the estuary of the North Mumbai coast. A total of 1197 specimens of M. cephalus, including 546 eggs, 271 larvae, 235 juveniles, and 235 adults, were collected from four sampling stations in the Karanja estuary between January to October 2022. Water quality parameters, plankton dynamics in the estuary, and the reproductive and feeding biology of M. cephalus were also examined. The eggs, larvae, juveniles, and adults were identified using traditional morpho-meristic and DNA barcoding techniques. The results revealed a potential spawning ground of M. cephalus in the Karanja estuary. The results of reproductive biology also confirmed the occurrence of matured fishes during May-July. The abundance of eggs and larvae at the estuary's mouth and the presence of juveniles and mature individuals of M. cephalus dominantly in the Karanja estuary from May to July infer the presence of a spawning site. It is also recorded that M. cephalus spawn in higher salinity (35 ppt) and seawater temperature (33 °C) where the hatching of offspring takes place successfully. This study emphasizes the significance of DNA barcoding in guiding routine monitoring surveys and demonstrates its usefulness when combined with these techniques in identifying fish spawning grounds. The study findings will serve as baseline information to develop effective conservation and management strategies and protect the ideal spawning stock., (© 2023. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Fish frequently shift their distribution ranges as a result of changes in preferred environmental factors. Knowledge on distribution of fish in relation to their environmental optima is crucial for improving the understanding of fishing grounds and planning sustainable exploitation. This study investigated the monthly variability in environmental factors impacting the catch rate and the spatio-temporal distribution patterns of fish along northwest coast of India (NWCI) from 2017 to 2019. The time series images of sea surface temperature (SST), sea surface height anomaly (SSHa), chlorophyll-a concentration (CHL), and euphotic depth (Zeu) indicate close coupling between bio-physical variables in the region. Generalized Additive Model (GAM) applied to the catch rate of mid-water trawlers found that CHL and Zeu were the most influential variables for ribbonfish distribution, while CHL and SST influence squid distribution and SST and SSHa influence cuttlefish distribution. The total deviation explained 37.70 %, 10.70 %, and 22.28 % in the final model for simulating the spatio-temporal distribution of ribbonfish, squid, and cuttlefish, respectively. Environmental factors were significant in the final GAM model (p < 0.05). Spatio-temporal distribution patterns of fishery resources from mid-water trawlers showed that they were related to biophysical changes in the northwest coast of India. The high catch rate was observed in the northern latitudes during the post-monsoon (October), the major fishing season in the region. However, it shrank and shifted to southern latitudes during the winter (January). This study could be adapted to nearby countries in the Arabian Sea region for an effective and useful tool to monitor and manage the fishery resources. Furthermore, it could aid in decision-making for policymakers and resource managers to formulate strategies for holistic marine fishery management and sustainable resource exploitation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

This study investigated the diet composition and microplastic contamination in six fish species collected from the creek area of northeastern Arabian Sea. The results show that the diet of the fish is mainly composed of shrimps, algae, fish, and zooplankton, with microplastics constituting up to 4.83 % (Index of Preponderance) of their diet. The average abundance of microplastics ranges from 5.82 to 7.69 items per fish, and their ingestion is influenced by seasonal variation, gut fullness, and trophic level. Microplastic contamination has no significant effect on the condition factor and hepatosomatic index of the fish species. However, polymer hazard index indicates that microplastic pollution in fish is associated with a low to high risk factor, which might cause potential harm to aquatic lives and higher vertebrates via food chain. Therefore, this study highlights the need for immediate attention and effective regulations to reduce microplastic pollution to protect marine life., Competing Interests: Declaration of competing interest We are declaring that there is no conflict of interest in publishing the manuscript. We also declare that it is not under consideration for publication elsewhere, that its publication is approved by co-author and tacitly or explicitly by the responsible authorities where the work was carried out, and that, if accepted, it will not be published elsewhere in the same form, in English or in any other language, including electronically without the written consent of the copyright holder., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

The present study reports site-specific data on the seasonal variation in microplastic abundance and characteristics in coastal sediments along the North Eastern Arabian Sea, India. The abundance of MP in coastal sediments ranged from 4400 to 15,300 items/kg dry weight (DW), with the dominance of the size ranging between 100 and 500 μm. In the studied sediment samples, fibers were the most dominant form, followed by fragments. Ten different microplastics polymers were recorded during the study with dominance of polyethylene, polyester, polyamide and all the recorded plastic items in the sediments were denser than water, except polyethylene. The mean abundance of MP in sediments was significantly higher in the monsoon season. During this season, freshwater flow increases to the sea, which brings a higher concentration of microplastics from catchment areas. For a better insight, more time-series data and research are required to assess the source of MP pollution, understand spatial-temporal variations in MP abundance and their possible hazardous impacts on marine organisms and the environment., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. No financial interests/personal relationships., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

In this study, the microplastics (MPs) abundance, characteristics and their variations across three popular beaches of highly populated and largest megacity of India were documented using clams as an indicator species. The abundance of MPs in clams was 77.39 MPs items/g in soft tissue parts and 198.82 items/individual, while in coastal waters and sediments the abundance was 537.5 ± 95 items/L and 10,568.3 ± 3053.3 items/kg respectively. The observed higher microplastic diversity integrated (MDII) indicates numerous sources contributing to microplastics pollution and higher microplastic index (MPI) indicates greater bioavailability of MPs to clams. The bulk of the microplastics recovered from clams (55.78 %), coastal sediments (52.27 %) and coastal sea waters (54 %) belong to the <100 μm size range, and were identified as LDPE and polypropylene, polyamide and polystyrene. This investigation tried to validate the potential trophic transfer concerns associated with clam intake to both human health and marine ecology., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Microplastics (MPs) are anthropogenic pollutants which can adsorb toxic substances from surrounding water and absorb into the fish body. During the present study, MPs were observed in water, sediment, and gastrointestinal tracts of marine biota samples collected from the coastal waters of Mumbai, India. The mean abundances of MPs recorded in water samples 372 ± 143 items/liter and 9630 ± 2947 items/kg dry weight (DW) in sediment samples. The mean abundance of MPs in pelagic fish species varied from 6.74 ± 2.74 to 9.12 ± 3.57 items/individual and in the demersal species the values ranged from 5.62 ± 2.27 to 6.6 ± 2.98 items/individual. Shape-wise, four type of MPs were observed in the surface waters, sediments and all studied species, predominantly fibers, followed by fragments, pellets/beads, and films. Seven different colors of MPs (red, blue, black, translucent, brown, green, and yellow) were observed from studied samples. MPs of size below 250 μm formed the dominant size in the surface water, sediments, and biota samples except Bombay duck and Malabar sole fish. Based on Raman spectroscopy analysis, eleven types of plastic polymers identified from all studied samples. Thus, presence of MPs in studied biota indicates the transfer of MPs through interlinked food chain/web to higher trophic levels and the occurrence of MPs in the fish gut underlines the necessity of more studies on processing interventions for reducing the microplastic contamination in fish for human consumption., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Background: The taxonomic status and geographical distribution of M. tengara are vague. No genetic diversity and phylogenetic study have been done till now to resolve its identity and distribution. In the present study, an integrated taxonomic approach has been applied to clarify the taxonomic status, identity, and distribution of bagrid catfish, Mystus tengara., Methods and Results: Comparative morphometric evaluation of M. tengara identified in the present study from distant geographical locations revealed variations of the traits in response to body length and environment, without significant genetic distance. The observed morphometric traits of M. tengara were found to be overlapping with available morphometric traits of M. tengara, M. carcio and M. vittatus. Maximum likelihood and Bayesian phylogenetic analysis based on mitochondrial cytochrome c oxidase (COI) gene also could not resolve their identity, and five paraphyletic clades comprising of M. tengara, M. vittatus, and M. carcio from India, Nepal, and Bangladesh were observed. Morphological and genetic evidence along with comparative evaluation of M. tengara, from its type locality, we consider M. tengara identified in the present study to be true, with its distribution extending from North East India to West Bengal, North India, Central India, Northern peninsular India, and Bangladesh., Conclusion: The observation of paraphyletic subclades and evaluation of genetic distance between subclades reveals the presence of four cryptic species. Further confirmation on the identity of M. vittatus and M. carcio, by an integrated taxonomic approach based on fresh specimens collected from the type locality, is required., (© 2021. The Author(s), under exclusive licence to Springer Nature B.V.)

The mangroves are well known for their ecological services and livelihood support to humankind. The mangrove forest is experiencing extreme pressure due to anthropogenic activities, mainly the debris pollution posing great harm to the mangrove ecosystems. The abundance, sources, and composition of surficial and trapped debris items in the six contiguous mangrove regions of Mumbai were studied by the belt-transect and quadrats method. A total number of 3526 surficial debris items (368 kg) were collected from twenty belt transects. The estimated mean surficial debris was 8.8 ± 3.4 pieces/m 2 with a weight of 920 ± 317 g/m 2 . The mean trapped debris was 35 ± 10 pieces/tree and 2514 ± 758 g/tree. Plastic (62.4%) includes carry bags and food wrappers mainly. Shoreline/recreational activity-based debris (38.9%) and other items (32.7%) contributed significantly to the total debris pollution. The study provides evidence that the mangrove ecosystem acts as a natural filter and trap for coastal water debris. The trapped debris is a potential risk to the mangroves due to the barrier created on the canopy surface for the incident solar radiation utilized for photosynthesis. By conducting the cleaning programs in the mangrove vegetation stretches, the ecological disturbances to the mangrove ecosystems can be minimized. Further, the regular removal of trapped debris will complement coastal pollution management. The data generated from this study will help the policymakers and resource managers about the effective control and management of debris pollution in the mangroves region., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Accumulation of microplastics (MPs) in marine organisms poses an imminent environmental threat and health risk due to the possibility of trophic transfer of accumulated MPs in ecologically important food chains. In this context, a field-level study was conducted on the fishing grounds of the north eastern part of the Arabian Sea through experimental fishing, and the gastrointestinal tracts (GT) of three different species of shrimps (n=180) were examined for the incidence of microplastics. The results showed that all shrimp caught from the fishing grounds had significant levels of MPs in the gastrointestinal tracts. A total number of 1220 microplastic items were recorded from the pooled samples, with an average of 6.78 ± 2.80 items per individual. The gastrointestinal tract showed an average number of 70.32 ± 34.67 MPs per gram of the gut material. The MPs with the size range of 100-250 μm were the most abundant form found in the shrimp species analyzed. Among the colored MP particles, black color was the most dominant (30.16%) form of MP. Fibers, fragments, pellets, beads, and films were the common morphotypes; however, fibers showed an occurrence of 39.40%, 47.39%, and 41.89% in the GTs of Metapenaeus monoceros, Parapeneopsis stylifera, and Penaeus indicus, respectively. In the present study, six types of plastic polymers were identified from the GTs of the studied samples. The findings confirm the presence of microplastics in the natural habitats of shrimps beyond the coast and indicate that shrimps caught from these coastal fishing grounds contain MPs in their gut. The findings underline the immediate scientific intervention for the microplastic reduction in the marine environment., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Anthropogenic marine litters or microplastics (MPs) accumulation in marine organisms is an emerging environmental threat. In this background, the gastrointestinal tract of Coilia dussumieri (n = 150) was studied in the samples collected from the fishing grounds of the north east coast of Arabian Sea through experimental fishing. Out of the total 150 specimens collected, all showed the incidence of microplastic particulates in the guts. The average abundance of MPs was found to be 6.98 ± 2.73 items/individual whereas gastrointestinal tract recorded with an average number of 28.84 ± 10.13 MPs/g in the gut material. The dominant MPs were found in the size range of 100-250 μm and of fibers type mostly blue in color. The prevalence of MPs in Coilia dussumieri is a matter of serious concern due to its ecological consequences due to trophic transfer in the connected food chains and probable threats to the health of human beings consuming the fish., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

A new fish species, Stolephorus tamilensis sp. nov., is described from the East coast of India. The major distinguishing characters are 5-6 small needle-like pre-pelvic scutes on belly; maxilla tip pointed, reaching to border of operculum, concave and indented in the preoperculum; 25-28 gill rakers on lower lobe of the first branchial arch; dorsal fin without spine; 17-19 anal-fin rays. Moreover, S. tamilensis sp. nov. present higher average genetic divergence values at mitochondrial cytochrome c oxidase subunit I and 16S rDNA loci in comparison with congeners. Also, nucleotide diagnostic characters exclusive to S. tamilensis are identified. Neighbor-joining analysis revealed close relation between S. tamilensis  and S. andhraensis.

This study analyzes the trophic structure of fish assemblages in a well-mixed tropical estuary, Zuari, located in southwest coast of India. A total of 224 fish species were collected between September 2013 and August 2016 from 324 sampling events from 9 sampling stations using surface and bottom set gillnets. The sampling events were designed to cover three major seasons such as the pre-monsoon, monsoon, and post-monsoon. For each sampling event, abiotic variables such as temperature, salinity, dissolved oxygen, and transparency of the water were recorded. The data obtained for abundance of fish species was subjected to cluster analysis and non-metric multidimensional scaling. The results defined six spatio-temporally varying groups (clusters) within Zuari estuary. Canonical correspondence analysis demonstrated that temperature, salinity, dissolved oxygen, and transparency were important in determining the fish assemblages in Zuari. The estuarine resident species were abundant in the inner zone (riverine side) of the estuary, where the salinity and temperature recorded lower dimensions compared to middle and outer zones (marine side). However, the inner shallow zone of the estuary was not a preferred habitat for the migrating marine species. Majority of the fish species preferred middle and outer zones and post-monsoon and pre-monsoon seasons for inhabiting the estuary. The present study furnishes a reference data for the spatio-temporal dynamics of fish assemblages in tropical monsoonal estuaries.

The present work deals with assessment of baseline radionuclide concentration in marine organisms around selected coasts of Maharashtra, India. This baseline study highlights concentrations of natural and fallout radionuclides in finfish and shellfish species found in the surrounding seawater. Water and fish samples were collected, processed, and analyzed for 238 U, 226 Ra, 228 Ra, 232 Th, 40 K, and 137 Cs by high-resolution gamma spectrometry. 238 U, 226 Ra, 228 Ra, 232 Th, 40 K, and 137 Cs concentrations were found to be in the range of ≤1.5, ≤2.0, ≤0.4, ≤1.5, ≤8.0 to 258, and ≤0.2 Bq/kg, respectively. The seasonal study revealed the maximum concentration in premonsoon season. Activity concentrations were higher in pelagic fish than those in demersal fish. A higher concentration factor was reported in shellfish than in finfish., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Gobiids constitute a major proportion of fish population in both tropical and temperate freshwater as well as marine ecosystem. Due to their small size, cryptic ecology and ambiguous morphological characters, gobiids diversity was not documented completely. In this study, DNA barcodes were generated for 11 species of gobiids, collected from the Ashtamudi Lake, India. The mitochondrial COI gene was amplified using universal primers and the resulted 650 bp amplicon was sequenced. The COI barcodes clearly distinguished all the species with high inter-specific genetic distance values than intra-specific values based on K2P (Kimura 2 Parameter) model. The average genetic distance (K2P model) within species, genus and family was 1.2%, 22.2% and 25.3%, respectively. In addition to barcode-based species identification system, Nucleotide Diagnostic (ND) characters specific for species were identified. The Neighbor-Joining tree revealed distinct clusters shared by the species of same genera.

Identification of elasmobranchs by conventional taxonomy is difficult due to similarities in morphological characters. Species-specific molecular markers are good choice for identifying species irrespective of it's life stage. Recently, mitochondrial cytochrome c oxidase subunit I (COI) gene got global recognition as a barcode gene to discriminate all animals up-to species level. In this study, mitochondrial COI partial gene was used to develop DNA barcodes for 18 species of elasmobranchs (10 species of sharks and 8 species of rays). The COI barcodes clearly distinguished all the species with high interspecific distance values than intraspecific values. The average interspecific and intraspecific distance values are 8.6% and 0.3% for sharks, respectively and 12.4% and 0.63% for rays, respectively using K2P method. The Neighbor-Joining tree showed distinct clusters shared by the species of same genera. The COI barcodes were also used to estimate allopatric divergences for selected species across broad geographical locations and found that Sphyrna lewini, Aetobatus narinari and Neotrygon kuhlii have cryptic diversity.

The elasmobranchs (sharks, rays and skates) being the extant survivors of one of the earliest offshoots of the vertebrate evolutionary tree are good model organisms to study the primitive vertebrate conditions. They play a significant role in maintaining the ecological balance and have high economic value. Due to over-exploitation and illegal fishing worldwide, the elasmobranch stocks are being decimated at an alarming rate. Appropriate management measures are necessary for restoring depleted elasmobranch stocks. One approach for restoring stocks is implementation of conservation measures and these measures can be formulated effectively by knowing the evolutionary relationship among the elasmobranchs. In this study, a total of 30 species were chosen for molecular phylogeny studies using mitochondrial cytochrome c oxidase subunit I, 12S ribosomal RNA gene and nuclear Internal Transcribed Spacer 2. Among different genes, the combined dataset of COI and 12S rRNA resulted in a well resolved tree topology with significant bootstrap/posterior probabilities values. The results supported the reciprocal monophyly of sharks and batoids. Within Galeomorphii, Heterodontiformes (bullhead sharks) formed as a sister group to Lamniformes (mackerel sharks): Orectolobiformes (carpet sharks) and to Carcharhiniformes (ground sharks). Within batoids, the Myliobatiformes formed a monophyly group while Pristiformes (sawfishes) and Rhinobatiformes (guitar fishes) formed a sister group to all other batoids.

Comparative study has been done to examine the biodiversity and ecological status of the intertidal region of Tata Institute of Fundamental Research (TIFR), Bandstand and National Centre for Performing Arts (NCPA) rocky beaches in Mumbai, West coast of India. A total of 50 species of intertidal organisms were recorded from these shores. Shannon and Simpson's diversity index, Margalefs richness index and Pielou's evenness index indicated different level of ecological state of the shore in different months. Dendrograms and 2-D non metric MDS ordination from Bray-Curtis similarity matrix of occurrence of intertidal organisms from these sites showed highest similarity and combination pattern of occurrence between Nerita oryzarum and Planaxis sulcatus in TIFR and Bandstand shore. Nerita oryzarum and Tactarius malaccanus at NCPA shore. Abundance/biomass comparison (ABC) method of determining level of disturbance also pointed towards the polluted status of these shores. Study concludes that though these beaches are highly disturbed due to anthropogenic activities, they still support a rich intertidal biodiversity which need immediate attention for protection and conservation.

In the present study, a survey of Mahim creek and Bay area was undertaken that indicated absence of fauna, particularly molluscs from the area, which was a repository in the past. During bioassay experiments of Mahim creek water, the clams G. divaricatum and C. antiquata could not open their valves in 100% creek water and died within 12 hrs of exposure. The 96 hrs LC50 values of Mahim creek water for G. divaricatum and C. antiquata were found to be 20% and 40% respectively during summer and 38% and 57% respectively during rainy season. When two sets of the clams were transplanted at Mahim creek, they died within 12 hrs. These experiments suggest the extreme level of pollution in the area. This level of pollution is responsible for transforming the area into barren locality in terms of fauna, specially the rich molluscan diversity. However, Gorai creek was found to be comparatively very less polluted and it still serves as breeding and nursery ground for various fishes and prawn species. Hence it must be protected and conserved.