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To monitor the changes in fish biodiversity and to elucidate the factors responsible for these changes, the landings composition (LC) over the past 30 years in the Nile-Delta lakes was quantitatively analyzed. The LC data indicates a shift in target species towards demersal opportunistic species. A significant difference (P < 0.001) between two main intervals highlighted in both PERMANOVA and PCA plot; the first interval (1991–2002) is dominated by Tilapia and rare species, while the second interval (2003−2020) is dominated by the opportunistic catfish and mullet species. Noticeable declines in species richness and landings of rare species were observed, where rare taxa either have been overexploited or they may be positively affected by increasing pollution levels than do other dominated species such as Tilapia. In contrast, opportunistic fish species such as catfish and mullet, have flourished in such polluted water due to their ability to tolerate seasonal pollution-related hypoxia.

Rivers networks represent hierarchical dendritic habitats within terrestrial landscapes and differences in connectivity and land use influence dispersal, and consequently biodiversity patterns. We, therefore, measured variation in water chemistry and fish abundance and related these to a number of landscape characteristics (e.g., wetland, urban, wooded, and agricultural) in the River Klaralven and its 30 permanently flowing tributaries. We hypothesized that these environmental attributes would differ between tributary and main stem habitat and that these differences would be driven by landscape attributes including land use. We found considerable intertributary variation in temperature and nutrient levels, and between the tributaries and the main stem. Generally, water temperature was lower in the tributaries, whereas nutrient levels were higher in the tributaries. The lower water temperature has implications for coldwater fishes, and we found two fishes, burbot and lamprey, associated with coldwater tributaries. We also found an inverse relationship between water quality and anthropogenic land use. Protecting tributaries with low anthropogenic impact will likely become increasingly important with ongoing global warming as they can function as thermal refugia for coldwater fishes. Hence, this study underscores the need to evaluate water courses at regional scales to identify spatial refuges and ensure connectivity.

Rivers networks represent hierarchical dendritic habitats within terrestrial landscapes and differences in connectivity and land use influence dispersal, and consequently biodiversity patterns. We, therefore, measured variation in water chemistry and fish abundance and related these to a number of landscape characteristics (e.g., wetland, urban, wooded, and agricultural) in the River Klaralven and its 30 permanently flowing tributaries. We hypothesized that these environmental attributes would differ between tributary and main stem habitat and that these differences would be driven by landscape attributes including land use. We found considerable intertributary variation in temperature and nutrient levels, and between the tributaries and the main stem. Generally, water temperature was lower in the tributaries, whereas nutrient levels were higher in the tributaries. The lower water temperature has implications for coldwater fishes, and we found two fishes, burbot and lamprey, associated with coldwater tributaries. We also found an inverse relationship between water quality and anthropogenic land use. Protecting tributaries with low anthropogenic impact will likely become increasingly important with ongoing global warming as they can function as thermal refugia for coldwater fishes. Hence, this study underscores the need to evaluate water courses at regional scales to identify spatial refuges and ensure connectivity.

Aim: Greenland is one of the places on Earth where the effects of climate change are most evident. The retreat of sea ice has made East Greenland more accessible for longer periods during the year. East Greenland fjords have been notoriously difficult to study due to their remoteness, dense sea ice conditions and lack of infrastructure. As a result, biological monitoring across latitudinal gradients is scarce in East Greenland and relies on sporadic research cruises and trawl data from commercial vessels. We here aim to investigate the transition in fish and marine mammal communities from South to Northeast Greenland using environmental DNA (eDNA). Location: South to Northeast Greenland. Methods: We investigated the transition in fish and marine mammal communities from South to Northeast Greenland using eDNA metabarcoding of seawater samples. We included both surface and mesopelagic samples, collected over approximately 2400 km waterway distance, by sampling from Cape Farewell to Ella Island in August 2021. Results: We demonstrate a clear transition in biological communities from south to northeast, with detected fish and mammal species matching known distributions. Samples from the southern areas were dominated by capelin (Mallotus villosus) and redfish (Sebastes), whereas northeastern samples were dominated by polar cod (Boreogadus saida), sculpins (Myoxocephalus) and ringed seal (Pusa hispida). We provide newly generated 12S rRNA barcodes from 87 fish species, bringing the public DNA database closer to full taxonomic coverage for Greenlandic fish species for this locus. Main Conclusions: Our results demonstrate that eDNA sampling can detect latitudinal shifts in marine biological communities of the Arctic region, which can supplement traditional fish surveys in understanding species distributions and community compositions of marine vertebrates. Importantly, sampling of eDNA can be a feasible approach for detecting northward range expansions in remote areas as

Rivers networks represent hierarchical dendritic habitats within terrestrial landscapes and differences in connectivity and land use influence dispersal, and consequently biodiversity patterns. We, therefore, measured variation in water chemistry and fish abundance and related these to a number of landscape characteristics (e.g., wetland, urban, wooded, and agricultural) in the River Klaralven and its 30 permanently flowing tributaries. We hypothesized that these environmental attributes would differ between tributary and main stem habitat and that these differences would be driven by landscape attributes including land use. We found considerable intertributary variation in temperature and nutrient levels, and between the tributaries and the main stem. Generally, water temperature was lower in the tributaries, whereas nutrient levels were higher in the tributaries. The lower water temperature has implications for coldwater fishes, and we found two fishes, burbot and lamprey, associated with coldwater tributaries. We also found an inverse relationship between water quality and anthropogenic land use. Protecting tributaries with low anthropogenic impact will likely become increasingly important with ongoing global warming as they can function as thermal refugia for coldwater fishes. Hence, this study underscores the need to evaluate water courses at regional scales to identify spatial refuges and ensure connectivity.

Rivers networks represent hierarchical dendritic habitats within terrestrial landscapes and differences in connectivity and land use influence dispersal, and consequently biodiversity patterns. We, therefore, measured variation in water chemistry and fish abundance and related these to a number of landscape characteristics (e.g., wetland, urban, wooded, and agricultural) in the River Klaralven and its 30 permanently flowing tributaries. We hypothesized that these environmental attributes would differ between tributary and main stem habitat and that these differences would be driven by landscape attributes including land use. We found considerable intertributary variation in temperature and nutrient levels, and between the tributaries and the main stem. Generally, water temperature was lower in the tributaries, whereas nutrient levels were higher in the tributaries. The lower water temperature has implications for coldwater fishes, and we found two fishes, burbot and lamprey, associated with coldwater tributaries. We also found an inverse relationship between water quality and anthropogenic land use. Protecting tributaries with low anthropogenic impact will likely become increasingly important with ongoing global warming as they can function as thermal refugia for coldwater fishes. Hence, this study underscores the need to evaluate water courses at regional scales to identify spatial refuges and ensure connectivity.

Rivers networks represent hierarchical dendritic habitats within terrestrial landscapes and differences in connectivity and land use influence dispersal, and consequently biodiversity patterns. We, therefore, measured variation in water chemistry and fish abundance and related these to a number of landscape characteristics (e.g., wetland, urban, wooded, and agricultural) in the River Klaralven and its 30 permanently flowing tributaries. We hypothesized that these environmental attributes would differ between tributary and main stem habitat and that these differences would be driven by landscape attributes including land use. We found considerable intertributary variation in temperature and nutrient levels, and between the tributaries and the main stem. Generally, water temperature was lower in the tributaries, whereas nutrient levels were higher in the tributaries. The lower water temperature has implications for coldwater fishes, and we found two fishes, burbot and lamprey, associated with coldwater tributaries. We also found an inverse relationship between water quality and anthropogenic land use. Protecting tributaries with low anthropogenic impact will likely become increasingly important with ongoing global warming as they can function as thermal refugia for coldwater fishes. Hence, this study underscores the need to evaluate water courses at regional scales to identify spatial refuges and ensure connectivity.

Aim: Greenland is one of the places on Earth where the effects of climate change are most evident. The retreat of sea ice has made East Greenland more accessible for longer periods during the year. East Greenland fjords have been notoriously difficult to study due to their remoteness, dense sea ice conditions and lack of infrastructure. As a result, biological monitoring across latitudinal gradients is scarce in East Greenland and relies on sporadic research cruises and trawl data from commercial vessels. We here aim to investigate the transition in fish and marine mammal communities from South to Northeast Greenland using environmental DNA (eDNA). Location: South to Northeast Greenland. Methods: We investigated the transition in fish and marine mammal communities from South to Northeast Greenland using eDNA metabarcoding of seawater samples. We included both surface and mesopelagic samples, collected over approximately 2400 km waterway distance, by sampling from Cape Farewell to Ella Island in August 2021. Results: We demonstrate a clear transition in biological communities from south to northeast, with detected fish and mammal species matching known distributions. Samples from the southern areas were dominated by capelin (Mallotus villosus) and redfish (Sebastes), whereas northeastern samples were dominated by polar cod (Boreogadus saida), sculpins (Myoxocephalus) and ringed seal (Pusa hispida). We provide newly generated 12S rRNA barcodes from 87 fish species, bringing the public DNA database closer to full taxonomic coverage for Greenlandic fish species for this locus. Main Conclusions: Our results demonstrate that eDNA sampling can detect latitudinal shifts in marine biological communities of the Arctic region, which can supplement traditional fish surveys in understanding species distributions and community compositions of marine vertebrates. Importantly, sampling of eDNA can be a feasible approach for detecting northward range expansions in remote areas as

Co-management is increasingly recognized as an effective model for managing fisheries, but little information exists on whether co-management can produce effects in species other than the target species. Fishery co-management in the tropics, where fish diversity is high and fish catches tend to be multispecies, is prone to produce assemblage-wide effects via alterations in the food web and changes in the overall capture of non-target species. Here, we assessed the effects of co-management for the species Arapaima sp. in relation to the structure and composition of the overall fish assemblage in floodplain lakes of the central Amazon Basin. These floodplain lakes are managed under a system of zoning of fishing activities. We used data from surveys of six floodplain lakes, including two lakes of each of three categories (lakes where fishing is prohibited, limited-access lakes, and open fishing lakes). The surveys were carried out before and after implementation of co-management, through gillnet fishing. The study area was the lower Solimoes River, in the Amazon Basin, Brazil. Statistical models showed significant changes in the composition and structure of the fish assemblages after the implementation of the co-management, regardless of the zoning category. Through regulation of gear use and fishing practices, co-management allowed the colonization of species that had not been present before, which lead to higher richness and consequently increased fish sizes, abundance and biomass. Species of sedentary habits, migrants of short and medium distances, with commercial importance benefited the most from co-management. In the results presented in temporal scale, it was possible to observe a potential spillover effect being provided by the lakes where fishing is prohibited (no-take zones) and those of limited access that benefited those open to fishing. Thus, co-management had positive effects in the structure and composition of fish assemblages in all lakes, regardless of

This report provides an assessment of the results of a five-year collaboration between WorldFish and the Fisheries and Animal Resources Development Department (F&ARD) that was intended to support implementation of the State Fishery Policy of Odisha. The assessment critically examines progress, achievements, and learning with the WorldFish cooperation, covering various dimensions of fisheries and aquaculture productivity. poverty alleviation, food security and nutrition, household resilience, and women’s empowerment.

Co-management is increasingly recognized as an effective model for managing fisheries, but little information exists on whether co-management can produce effects in species other than the target species. Fishery co-management in the tropics, where fish diversity is high and fish catches tend to be multispecies, is prone to produce assemblage-wide effects via alterations in the food web and changes in the overall capture of non-target species. Here, we assessed the effects of co-management for the species Arapaima sp. in relation to the structure and composition of the overall fish assemblage in floodplain lakes of the central Amazon Basin. These floodplain lakes are managed under a system of zoning of fishing activities. We used data from surveys of six floodplain lakes, including two lakes of each of three categories (lakes where fishing is prohibited, limited-access lakes, and open fishing lakes). The surveys were carried out before and after implementation of co-management, through gillnet fishing. The study area was the lower Solimoes River, in the Amazon Basin, Brazil. Statistical models showed significant changes in the composition and structure of the fish assemblages after the implementation of the co-management, regardless of the zoning category. Through regulation of gear use and fishing practices, co-management allowed the colonization of species that had not been present before, which lead to higher richness and consequently increased fish sizes, abundance and biomass. Species of sedentary habits, migrants of short and medium distances, with commercial importance benefited the most from co-management. In the results presented in temporal scale, it was possible to observe a potential spillover effect being provided by the lakes where fishing is prohibited (no-take zones) and those of limited access that benefited those open to fishing. Thus, co-management had positive effects in the structure and composition of fish assemblages in all lakes, regardless of

Dataset: Gill Net Catch Data, Vertebrate caught with gill net in Sabine Lake, Galveston Bay, Matagorda Bay, San Antonio Bay, Aransas Bay, Corpus Christi Bay, Upper Laguna Madre, and Lower Laguna Madre from 1986 to 2018 (except in Sabine Lake sampling begun in 1986). For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/828794, NSF Division of Ocean Sciences (NSF OCE) OCE-1656923

Dataset: Gill Net Catch Data, Vertebrate caught with gill net in Sabine Lake, Galveston Bay, Matagorda Bay, San Antonio Bay, Aransas Bay, Corpus Christi Bay, Upper Laguna Madre, and Lower Laguna Madre from 1986 to 2018 (except in Sabine Lake sampling begun in 1986). For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/828794, NSF Division of Ocean Sciences (NSF OCE) OCE-1656923

Dataset: Gill Net Catch Data, Vertebrate caught with gill net in Sabine Lake, Galveston Bay, Matagorda Bay, San Antonio Bay, Aransas Bay, Corpus Christi Bay, Upper Laguna Madre, and Lower Laguna Madre from 1986 to 2018 (except in Sabine Lake sampling begun in 1986). For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/828794, NSF Division of Ocean Sciences (NSF OCE) OCE-1656923

Sponges have recently been proposed as ideal candidates to act as natural samplers for environmental DNA due to their efficiency in filtering water. However, validation of the usefulness of DNA recovered from sponges to reveal vertebrate biodiversity patterns in Marine Protected Areas is still needed. Additionally, nothing is known about how different sponge species and morphologies influence the capture of environmental DNA and whether biodiversity patterns obtained from sponges are best described by quantitative or qualitative measures. In this study, we amplified and sequenced a vertebrate specific 12S barcode with a set of universal PCR primers (MiFish) for metabarcoding environmental DNA from fishes, to unveil fine-scale patterns of fish communities from natural-sampler DNA retrieved from 64 sponges (16 species) located in eutrophic and well-preserved coral reefs in Nha Trang Bay (central Vietnam). Ninety tropical fish species were identified from the sponges, corresponding to one third of the total local ichthyofauna reported from previous extensive conventional surveys. Significant differentiation in fish communities between eutrophic and well-preserved environments was observed, albeit eutrophication only explained a modest proportion of the variation between fish communities. Differences in efficiency of capturing fish environmental DNA among sponge species or morphologies were not observed. Overall, the majority of detected fish species corresponded to reef-associated small-sized species, as expected in coral reefs environments. Remarkably, pelagic, migratory, and deep-sea fish species were also recovered from sponge tissues, pointing out the ability of sponge natural sampled DNA to detect fishes that were not permanently associated to the biomes where the sponges were sampled. These results highlight the suitability of natural samplers as a cost-effective way to assess vertebrate diversity in hyper-diverse environments.

Typified by heterogeneous habitats, large rivers host diversified communities throughout their course. As the spatial organisation of fish communities within these ecosystems remains little studied, longitudinal gradients and spatial heterogeneities of fish diversity were analysed in the large temperate St. Lawrence River, Canada. We used two distinct datasets obtained from either seine nets or gillnets from governmental standardised fish surveys (1995–2012) consisting of a total of 299,662 individuals from 76 fish species captured in 1,051 sites. Results from diversity indices and multivariate analysis revealed a gradual downstream increase in taxonomic diversity, and a gradual change of the community structure along the river. In addition, we observed different fish communities within fluvial lakes and corridors and found significant differences in fish community structure between opposite shores. The fish communities described along the river using seine nets are spatially more heterogeneous than when described using gillnets. This discrepancy is likely resulting both from the more mobile species targeted by gillnets and sampling sites located farther from the shallower shoreline habitat targeted by seine nets. The organisation of fish communities stresses the need to implement science-based policies and actions to preserve biodiversity and restore communities distributed over large heterogeneous ecosystems.

A study was conducted to determine the ichthyofaunal diversity in Bankura district of West Bengal. The area is traversed by major and minor rivers, feeder channels, numerous ponds, bills, reservoirs which have made this drought-trodden district as the highest producer of aquatic products within the state. Field survey was conducted in randomly selected local markets covering twenty-two blocks of Bankura. Fish sampling was carried out using various conventional fishing gears. The entire region harbours a wide variety of aquatic fishes. A total number of 92 indigenous fish species belonging to 30 families were identified during this study. The Cyprinidae family dominated the population with its 36 varieties followed by Channidae, Siluridae and Bagridae. Sonamukhi block situated in Shali basin; Sarenga and Raipur of Kangsabati basin; Dwarkeshwar and seven bundhs- enriched Bishnupur were the major habitats of small indigenous fishes. This paper also denotes presence of 12 globally endemic freshwater fish species viz. Hypophthalmichthys molitrix, Cyprinus carpio, Labeo nandina, Tor khudree, Chitala chitala, Bagarius bagarius, Wallago attu, Ompok pabda, Ailia coila, Anguilla bengalensis, Parambassis lala, Oreochromis mossambicus. The substitution of native Clarias batrachus with invasive African catfish C. gariepinus was observed in various local markets. Some traders even promote illicit farming of this banned species for their own profit. As a consequence, the indigenous, nutritionally-enriched C. batrachus is becoming more endangered.

Understanding environmental biodiversity drivers in freshwater systems continues to be a fundamental challenge in studies of their fish assemblages. The present study seeks to determine the degree to which landscape variables of Amazonian floodplain lakes influences fish assemblages in these environments. Fish species richness was estimated in 15 Amazonian floodplain lakes during the high and low-water phases and correlated with the areas of four inundated wetland classes: (i) open water, (ii) flooded herbaceous, (iii) flooded shrubs and (iv) flooded forest estimated in different radius circular areas around each sampling site. Data were analyzed using generalized linear models with fish species richness, total and guilds as the dependent variable and estimates of buffered landscape areas as explanatory variables. Our analysis identified the significance of landscape variables in determining the diversity of fish assemblages in Amazonian floodplain lakes. Spatial scale was also identified as a significant determinant of fish diversity as landscape effects were more evident at larger spatial scales. In particular, (1) total species richness was more sensitive to variations in the landscape areas than number of species within guilds and (2) the spatial extent of the wetland class of shrubs was consistently the more influential on fish species diversity.

Les activités humaines ont profondément transformé les paysages aquatiques des grands fleuves en modifiant l’hétérogénéité et la connectivité de leurs habitats. Ces transformations ont mené à la disparition et au déclin de plusieurs espèces de poissons jadis abondantes. Malgré les actions entreprises afin d’atténuer l’érosion de la diversité ichtyologique, certaines populations de poissons sont encore en situation précaire. Ce constat témoigne de la nécessité de mieux comprendre en quoi les caractéristiques et modifications du paysage aquatique influencent l’organisation spatiale des commmunautés de poissons afin ultimement de définir des unités de gestion écologique. La présente thèse vise à mieux comprendre le rôle des caractéristiques hydromorphologiques et des modifications anthropiques sur l’hétérogénéité et la connectivité du paysage aquatique à différentes échelles spatiales et organisationnelles dans le fleuve Saint-Laurent (Québec, Canada). Partant d’une perspective à l’échelle de la portion fluviale portant sur la diversité des communautés de poissons, cette thèse se consacre ensuite, à une échelle spatio-temporelle plus fine, à l’accès aux habitats vitaux d’une espèce structurante pour la communauté. En effet, la connectivité entre les habitats assurant la survie des jeunes stades de vie du grand brochet (Esox lucius) vise à mieux comprendre le rôle des caractéristiques hydromorphologiques et des modifications anthropiques sur le déclin de cette espèce emblématique. Sur l’ensemble de la portion fluviale du Saint-Laurent (~350 km), un échantillonnage gouvernemental standardisé des communautés de poissons (1995-2013) a été analysé grâce à la combinaison d’analyses univariées sur les indices de diversité et d’analyses multivariées sur la structure d’abondance des espèces. Les analyses révèlent des résultats contrastés selon les indices utilisés et soulignent l’importance de considérer plusieurs facettes de la diversité. En effet, seul l’indice de diversité t

For decades, global climate change has directly and indirectly affected the structure and function of ecosystems. Abrupt changes in biodiversity have been observed in response to linear or sudden modifications to the environment. These abrupt shifts can cause long-term reorganizations within ecosystems, with communities exhibiting new functional responses to environmental factors. Over the last 3 decades, the Gironde estuary in southwest France has experienced 2 abrupt shifts in both the physical and chemical environments and the pelagic community. Rather than describing these shifts and their origins, we focused on the 3 inter-shift periods, describing the structure of the fish community and its relationship with the environment during these periods. We described fish biodiversity using a limited set of descriptors, taking into account both species composition and relative species abundances. Inter-shift ecosystem states were defined based on the relationship between this description and the hydro-physico-chemical variables and climatic indices defining the main features of the environment. This relationship was described using generalized linear mixed models on the entire time series and for each inter-shift period. Our results indicate that (1) the fish community structure has been significantly modified, (2) environmental drivers influencing fish diversity have changed during these 3 periods, and (3) the fish-environment relationships have been modified over time. From this, we conclude a regime shift has occurred in the Gironde estuary. We also highlight that anthropogenic influences have increased, which re-emphasizes the importance of local management in maintaining fish diversity and associated goods and services within the context of climate change.

For decades, global climate change has directly and indirectly affected the structure and function of ecosystems. Abrupt changes in biodiversity have been observed in response to linear or sudden modifications to the environment. These abrupt shifts can cause long-term reorganizations within ecosystems, with communities exhibiting new functional responses to environmental factors. Over the last 3 decades, the Gironde estuary in southwest France has experienced 2 abrupt shifts in both the physical and chemical environments and the pelagic community. Rather than describing these shifts and their origins, we focused on the 3 inter-shift periods, describing the structure of the fish community and its relationship with the environment during these periods. We described fish biodiversity using a limited set of descriptors, taking into account both species composition and relative species abundances. Inter-shift ecosystem states were defined based on the relationship between this description and the hydro-physico-chemical variables and climatic indices defining the main features of the environment. This relationship was described using generalized linear mixed models on the entire time series and for each inter-shift period. Our results indicate that (1) the fish community structure has been significantly modified, (2) environmental drivers influencing fish diversity have changed during these 3 periods, and (3) the fish-environment relationships have been modified over time. From this, we conclude a regime shift has occurred in the Gironde estuary. We also highlight that anthropogenic influences have increased, which re-emphasizes the importance of local management in maintaining fish diversity and associated goods and services within the context of climate change.

World heritage site-Sundarbans were declared as the world’s 560th Ramsar Wetlands site in 1992. Sundarbans ecosystem supports rich fisheries diversity and also natural biodiversity hot spot, because it is natural habitat of many endangered species. The Sundarbans is a home to a variety of faunal species, the total of 1586 species has been recorded which includes 481 Vertebrate species (30%), 1104 Invertebrate species (70%). Mangroves are the nursery and breeding grounds for several commercially important species of aquatic fauna like fish, shrimps and prawns etc. Mangrove ecosystems are of great ecological significance in the tropical and sub-tropical coast. Sundarbans mangrove provides a variety of ecosystem services. However, the Sundarban mangrove forest is the most threatened habitats in the world, increased population with few alternative livelihood opportunities poses a serious threat as it is the main cause of mangrove destruction. The total value of Sundarbans is not recognized and therefore often neglected in development planning. As a result Sundarbans conservation issue is getting less importance at the national level. The study reveals that major ecosystem services of Sundarbans are timber, fuel wood, fish, ecotourism, cyclone and storm protection, biodiversity, and habitat for flora and fauna. Timber, fuel wood and fish are more economical provisioning services in Sundarbans. It is noticed that there is decreasing tendency of overall revenue collection from the mangrove over the period of 2001-02 to 2009-10. The attention from national and international communities is needed for sustainable management and conservation of the Sundarbans. The study suggests that further research on total economic value of Sundarbans is needed for providing comprehensive scientific information for policy as well as for decision makers.

For decades, global climate change has directly and indirectly affected the structure and function of ecosystems. Abrupt changes in biodiversity have been observed in response to linear or sudden modifications to the environment. These abrupt shifts can cause long-term reorganizations within ecosystems, with communities exhibiting new functional responses to environmental factors. Over the last 3 decades, the Gironde estuary in southwest France has experienced 2 abrupt shifts in both the physical and chemical environments and the pelagic community. Rather than describing these shifts and their origins, we focused on the 3 inter-shift periods, describing the structure of the fish community and its relationship with the environment during these periods. We described fish biodiversity using a limited set of descriptors, taking into account both species composition and relative species abundances. Inter-shift ecosystem states were defined based on the relationship between this description and the hydro-physico-chemical variables and climatic indices defining the main features of the environment. This relationship was described using generalized linear mixed models on the entire time series and for each inter-shift period. Our results indicate that (1) the fish community structure has been significantly modified, (2) environmental drivers influencing fish diversity have changed during these 3 periods, and (3) the fish-environment relationships have been modified over time. From this, we conclude a regime shift has occurred in the Gironde estuary. We also highlight that anthropogenic influences have increased, which re-emphasizes the importance of local management in maintaining fish diversity and associated goods and services within the context of climate change.

For decades, global climate change has directly and indirectly affected the structure and function of ecosystems. Abrupt changes in biodiversity have been observed in response to linear or sudden modifications to the environment. These abrupt shifts can cause long-term reorganizations within ecosystems, with communities exhibiting new functional responses to environmental factors. Over the last 3 decades, the Gironde estuary in southwest France has experienced 2 abrupt shifts in both the physical and chemical environments and the pelagic community. Rather than describing these shifts and their origins, we focused on the 3 inter-shift periods, describing the structure of the fish community and its relationship with the environment during these periods. We described fish biodiversity using a limited set of descriptors, taking into account both species composition and relative species abundances. Inter-shift ecosystem states were defined based on the relationship between this description and the hydro-physico-chemical variables and climatic indices defining the main features of the environment. This relationship was described using generalized linear mixed models on the entire time series and for each inter-shift period. Our results indicate that (1) the fish community structure has been significantly modified, (2) environmental drivers influencing fish diversity have changed during these 3 periods, and (3) the fish-environment relationships have been modified over time. From this, we conclude a regime shift has occurred in the Gironde estuary. We also highlight that anthropogenic influences have increased, which re-emphasizes the importance of local management in maintaining fish diversity and associated goods and services within the context of climate change.

Fish species abundance, seasonal variation and condition factor (k) was assessed in this study between October 2012 and September 2013. Samples collected from Erinle reservoir were identified and sorted out into species, the morphometric parameters of each sample were measured using a measuring board graduated in cm and weighed using a Mettler balance (P 1210 model). Fulton’s condition factor (k) was calculated using the equation K=100W/L. Fish species identified were twelve: Alestes macrolepidotus, Chromidotilapia guntheri, Oreochromis niloticus, Sarotherodon galilaeus, Tilapia mariae, Tilapia zillii, Clarias gariepinus, Chrysichthys auratus, Hepsetus odoe, Mormyrus rume, Marcusenius senegalensis and Schilbe mystus. The species belong to seven families from a total of 561 fish samples with varying degree of abundance. S. galilaeus had the highest abundance of 55.08% of the total samples collected while C. gariepinus had the lowest abundance of 0.18% as only one sample was collected during the study period. Abundance of fish species was higher during the dry season than the raining season with 360 and 201 fish samples respectively. A. macrolepidotus, C. gariepinus and M. senegalensis were not observed during the raining season. Mean condition factor (k) showed the reservoir was favourable for all species except C. gariepinus, C. auratus, H. odoe, M. rume and S. mystus as their K-value was <1.0. The study concluded that Erinle reservoir can support fisheries provided anthropogenic influence is properly monitored and regulated by relevant authorities.

Lucknow a capital of Uttar Pradesh has vast potential of fish faunal diversity and offers considerable scope of inland fisheries development. Aquaculture activities in rural for most of the fisherman area. In order to establish fish faunal diversity of Lucknow a preliminary, data have been collected with the help of local fish farmers and market survey. Various lentic and lotic water bodies of different locations of the district for 9 months during 2014-2015 have been collected. During the study period, 83 fish species belonging to 58 Genera, 21 Families and 8 Orders have been identified. Cypriniformes was found the dominated Order with 56 species (68%) followed by Perciformes 9 species (11%) and Clupeiformes 6 species (7%). The present study showed that Lucknow possesses rich fish diversity but proper conservation measures are required to maintain sustainability and richness of the species diversity of the district.

Fish survey of river Ujh, an important clean water tributary of the river Ravi, in Kathua  district,  has revealed  the presence of 42 fish species belonging to 5 orders, 10 families and 27 genera. Fish fauna is dominated by Cypriniformes (27 species), followed by Siluriformes (10 species), Synbranchiformes (2 species), Perciformes (2 species) and Beloniformes (1 species). Fishing methods commonly employed include cast net, rod and hook, pocket net, poisoning, hand picking, stick, sickle and simple cloth. Fish diversity is fast depleting due to over exploitation, illegal fishing methods and fishing during breeding season.  There  are  great  prospects  of  increasing  fish  production  in  this  river  by  stocking  various  carps  in seasonal Ujh barrage at village Jasrota.

Fish survey of river Ujh, an important clean water tributary of the river Ravi, in Kathua  district,  has revealed  the presence of 42 fish species belonging to 5 orders, 10 families and 27 genera. Fish fauna is dominated by Cypriniformes (27 species), followed by Siluriformes (10 species), Synbranchiformes (2 species), Perciformes (2 species) and Beloniformes (1 species). Fishing methods commonly employed include cast net, rod and hook, pocket net, poisoning, hand picking, stick, sickle and simple cloth. Fish diversity is fast depleting due to over exploitation, illegal fishing methods and fishing during breeding season.  There  are  great  prospects  of  increasing  fish  production  in  this  river  by  stocking  various  carps  in seasonal Ujh barrage at village Jasrota.

Fish species abundance, seasonal variation and condition factor (k) was assessed in this study between October 2012 and September 2013. Samples collected from Erinle reservoir were identified and sorted out into species, the morphometric parameters of each sample were measured using a measuring board graduated in cm and weighed using a Mettler balance (P 1210 model). Fulton’s condition factor (k) was calculated using the equation K=100W/L. Fish species identified were twelve: Alestes macrolepidotus, Chromidotilapia guntheri, Oreochromis niloticus, Sarotherodon galilaeus, Tilapia mariae, Tilapia zillii, Clarias gariepinus, Chrysichthys auratus, Hepsetus odoe, Mormyrus rume, Marcusenius senegalensis and Schilbe mystus. The species belong to seven families from a total of 561 fish samples with varying degree of abundance. S. galilaeus had the highest abundance of 55.08% of the total samples collected while C. gariepinus had the lowest abundance of 0.18% as only one sample was collected during the study period. Abundance of fish species was higher during the dry season than the raining season with 360 and 201 fish samples respectively. A. macrolepidotus, C. gariepinus and M. senegalensis were not observed during the raining season. Mean condition factor (k) showed the reservoir was favourable for all species except C. gariepinus, C. auratus, H. odoe, M. rume and S. mystus as their K-value was <1.0. The study concluded that Erinle reservoir can support fisheries provided anthropogenic influence is properly monitored and regulated by relevant authorities.

Fish species abundance, seasonal variation and condition factor (k) was assessed in this study between October 2012 and September 2013. Samples collected from Erinle reservoir were identified and sorted out into species, the morphometric parameters of each sample were measured using a measuring board graduated in cm and weighed using a Mettler balance (P 1210 model). Fulton’s condition factor (k) was calculated using the equation K=100W/L. Fish species identified were twelve: Alestes macrolepidotus, Chromidotilapia guntheri, Oreochromis niloticus, Sarotherodon galilaeus, Tilapia mariae, Tilapia zillii, Clarias gariepinus, Chrysichthys auratus, Hepsetus odoe, Mormyrus rume, Marcusenius senegalensis and Schilbe mystus. The species belong to seven families from a total of 561 fish samples with varying degree of abundance. S. galilaeus had the highest abundance of 55.08% of the total samples collected while C. gariepinus had the lowest abundance of 0.18% as only one sample was collected during the study period. Abundance of fish species was higher during the dry season than the raining season with 360 and 201 fish samples respectively. A. macrolepidotus, C. gariepinus and M. senegalensis were not observed during the raining season. Mean condition factor (k) showed the reservoir was favourable for all species except C. gariepinus, C. auratus, H. odoe, M. rume and S. mystus as their K-value was <1.0. The study concluded that Erinle reservoir can support fisheries provided anthropogenic influence is properly monitored and regulated by relevant authorities.

Fish species abundance, seasonal variation and condition factor (k) was assessed in this study between October 2012 and September 2013. Samples collected from Erinle reservoir were identified and sorted out into species, the morphometric parameters of each sample were measured using a measuring board graduated in cm and weighed using a Mettler balance (P 1210 model). Fulton’s condition factor (k) was calculated using the equation K=100W/L. Fish species identified were twelve: Alestes macrolepidotus, Chromidotilapia guntheri, Oreochromis niloticus, Sarotherodon galilaeus, Tilapia mariae, Tilapia zillii, Clarias gariepinus, Chrysichthys auratus, Hepsetus odoe, Mormyrus rume, Marcusenius senegalensis and Schilbe mystus. The species belong to seven families from a total of 561 fish samples with varying degree of abundance. S. galilaeus had the highest abundance of 55.08% of the total samples collected while C. gariepinus had the lowest abundance of 0.18% as only one sample was collected during the study period. Abundance of fish species was higher during the dry season than the raining season with 360 and 201 fish samples respectively. A. macrolepidotus, C. gariepinus and M. senegalensis were not observed during the raining season. Mean condition factor (k) showed the reservoir was favourable for all species except C. gariepinus, C. auratus, H. odoe, M. rume and S. mystus as their K-value was <1.0. The study concluded that Erinle reservoir can support fisheries provided anthropogenic influence is properly monitored and regulated by relevant authorities.

Fish survey of river Ujh, an important clean water tributary of the river Ravi, in Kathua  district,  has revealed  the presence of 42 fish species belonging to 5 orders, 10 families and 27 genera. Fish fauna is dominated by Cypriniformes (27 species), followed by Siluriformes (10 species), Synbranchiformes (2 species), Perciformes (2 species) and Beloniformes (1 species). Fishing methods commonly employed include cast net, rod and hook, pocket net, poisoning, hand picking, stick, sickle and simple cloth. Fish diversity is fast depleting due to over exploitation, illegal fishing methods and fishing during breeding season.  There  are  great  prospects  of  increasing  fish  production  in  this  river  by  stocking  various  carps  in seasonal Ujh barrage at village Jasrota.

Fish survey of river Ujh, an important clean water tributary of the river Ravi, in Kathua  district,  has revealed  the presence of 42 fish species belonging to 5 orders, 10 families and 27 genera. Fish fauna is dominated by Cypriniformes (27 species), followed by Siluriformes (10 species), Synbranchiformes (2 species), Perciformes (2 species) and Beloniformes (1 species). Fishing methods commonly employed include cast net, rod and hook, pocket net, poisoning, hand picking, stick, sickle and simple cloth. Fish diversity is fast depleting due to over exploitation, illegal fishing methods and fishing during breeding season.  There  are  great  prospects  of  increasing  fish  production  in  this  river  by  stocking  various  carps  in seasonal Ujh barrage at village Jasrota.

Fish species abundance, seasonal variation and condition factor (k) was assessed in this study between October 2012 and September 2013. Samples collected from Erinle reservoir were identified and sorted out into species, the morphometric parameters of each sample were measured using a measuring board graduated in cm and weighed using a Mettler balance (P 1210 model). Fulton’s condition factor (k) was calculated using the equation K=100W/L. Fish species identified were twelve: Alestes macrolepidotus, Chromidotilapia guntheri, Oreochromis niloticus, Sarotherodon galilaeus, Tilapia mariae, Tilapia zillii, Clarias gariepinus, Chrysichthys auratus, Hepsetus odoe, Mormyrus rume, Marcusenius senegalensis and Schilbe mystus. The species belong to seven families from a total of 561 fish samples with varying degree of abundance. S. galilaeus had the highest abundance of 55.08% of the total samples collected while C. gariepinus had the lowest abundance of 0.18% as only one sample was collected during the study period. Abundance of fish species was higher during the dry season than the raining season with 360 and 201 fish samples respectively. A. macrolepidotus, C. gariepinus and M. senegalensis were not observed during the raining season. Mean condition factor (k) showed the reservoir was favourable for all species except C. gariepinus, C. auratus, H. odoe, M. rume and S. mystus as their K-value was <1.0. The study concluded that Erinle reservoir can support fisheries provided anthropogenic influence is properly monitored and regulated by relevant authorities.

Data from EU-Spain (Instituto Español de Oceanografía) bottom trawl surveys in the NAFO Regulatory Area (2002–2011) were analyzed to examine patterns on the South of Grand Banks (NAFO Div. 3NO) of groundfish assemblage structure and diversity in relation to depth. The 1160 hauls from the slope surveys spanned between 38 and 1460 m in depth. We focused on the 28 most abundant species, which made up 92.6% of the catch in terms of biomass. Assemblage structure was strongly correlated with depth. For the most part, changes in assemblages seem to be fairly continuous, although there were more abrupt changes at 300 m. Five assemblages were identified. Two shallow assemblages were found in the shelf. Assemblage I (Shallow) comprises the strata with depths lesser than 150 and include yellowtail flounder (Limanda ferruginea), American plaice (Hippoglossoides platessoides), Northern sand lance (Ammodytes dubius), moustache sculpin (Triglops murrayi), capelin (Mallotus villosus) and web sculpin (Hemitripterus americanus). Assemblage II (Shallow) includes the strata with depths between 151 and 300 m and comprises Atlantic cod (Gadus morhua), American angler (Lophius americanus), wolfish (Anarichas lupus) and thorny skate (Amblyraja radiata). Assemblage III (Intermediate) contains the depth strata between 301 and 600 m. Redfish (Sebastes spp.), spotted wolfish (Anarhichas minor), Arctic eelpout (Lycodes reticulatus), Northern wolfish (Anarhichas denticulatus), white hake (Urophycis tenuis), witch flounder (Glyptocephalus cynoglossus) and longfin hake (Phycis chesteri) were included in the intermediate assemblage. Finally, we found two deep clusters: Assemblage IV (Deep) contains the depths between 601 and 1000 m, and Assemblage V (Deep) the depth strata greater than 1001 m. Greenland halibut (Reinhardtius hippoglossoides), marlin-spike (Nezumia bairdii), roughhead grenadier (Macrourus berglax) and spinytail skate (Bathyraja spinicauda) formed Assemblage IV. Snubnosed spiny eel (

Laster stream is a major tributary of river Mandakini, which in turn is a major tributary of river Alaknanda. Stream traverses a distance of ~40 km before joining with river Mandakini at Suryaprayag (Tilwara) in Rudraprayag district (Uttarakhand), India. Present study reports existence of twenty one indigenous fish species belonging to eight genera, three families and two orders from the Laster stream. Schizothorax richardsonii (Cyprinidae family) was the dominating species followed by S. plagiostomus, Barilius sp., Tor sp., Noemacheilus sp., Pseudecheneis sp., Glyptothorax sp. The distribution pattern (diversity and abundance) of these species had negative co-relation with the increase in stream altitude. Habitat conditions in the stream varied considerably from headwater to main stream. Present study also describes the habitat specificity of fish assemblage. Maximum species diversity (18 species) was recorded from pool habitat and was the most preferred habitat. Least species diversity (09 species) was recorded from cascade habitat. Riffle and rapid habitat recorded no difference in species diversity.

Fish as a group, from biodiversity view point has the highest species diversity among all vertebrate taxa. Present communication deals with the reassessment of ichthyofaunal diversity of the river Bhilangna and its two sub tributaries, the Balganga and the Nailchami of Bhagirathi river system in Garhwal Himalaya. The observation made during study showed the occurrence of 22 fish species belonging to 2 orders, 3 families and 9 genera from varying habitat of falls, cascades, rapids, riffles and pools in various sections of river Bhilangna and its tributaries. Schizothorax richardsonii, S. plagiostomus are dominate species in the riverine segment of river Bhilangna while Cyprinus carpio (common carp) is the dominate species in impoundment segment of river Bhilangana (reservoir area). The comparison of results of present study with earlier reports revealed that fish fauna has decreased with passage of time in the Bhilangana river system which may be due to degradation and fragmentation of riverine habitat caused by various developmental activities, changes in the natural flow pattern of river, indiscriminate fishing by the use of destructive and unscientific fishing methods, and other natural calamities.

The present study was conducted to assess the current freshwater fish biodiversity status of an unexplored river Ghaghara, a major tributary of river Ganga in Uttar Pradesh, India. Altogether, 62 species of fish representing 48 genera and 24 families were described. The various diversity index packages have been used to assess the fish diversity and diversity is also correlated with habitat variables. The Cypriniformes was recorded to be the most predominated order, contributing to 41.8% of fish species followed by Siluriformes (36.4%). The study shows that this river supports considerable percentage of food fish (79.0%), aquarium fish (48.4%), highly priced fishes (33.9%) and also sport fish (9.7%). The threat status as per current IUCN Red List criteria showed that most of the species are under lower risk least concern (LRlc) category, however, Indian assessment shows that about 23% fish species under threatened list (EN= 4, VU=10). Several anthropogenic activities like barrages, waste water dumping, over fishing, sedimentation, change in land use pattern etc. were found responsible to threaten the fish diversity. As the threats to fish biodiversity in the Ghaghara river are slowly becoming serious and conservation of fishes has become urgent, and integrated and sustainable fisheries management plan should therefore be developed.

Khandwa is one of the districts of the state M.P. The Moghat reservoir is situated three Kilometers away in the Northwest area of Khandwa town on 210 49` 36`` N latitude and 760 20`56`` E longitudes. It is a man made reservoir built in 1897. The present study aims to   identify   the   fish fauna  presented in reservoir   and  to  give an initial  idea  about fish production  of Moghat reservoir of Khandwa M.P.

The present investigation was undertaken to study the fish diversity of Sogane and Santhekadur tanks, Shimoga. About 17 fish species were identified in these tanks which were represented by 4 orders, 11 families and 14 genera. The family Cyprinidae dominated the other groups of fish in both the tanks. The study of fish fauna of an aquatic body is useful for planning of fisheries development. The water quality analysis of these tanks was analyzed to study its influence on fish.

Since the 1960’s the crown-of-thorns starfish, Acanthaster planci¸ has devastated coral reefs. There are many competing theories about the causes for these outbreaks of A. planci. One of the leading theories is that it is an anthropogenic cause. As a result, Marine Protected Areas (MPA) may be a way to protect coral reefs from outbreaks of A. planci by removing anthropogenic effects and allowing the reef to protect itself. Coral reef health was assessed using fish population diversity, percent live coral reef coverage and density of A. planci. Lowest live coral reef coverage was 42.97% with 80.70% the highest. Highest Simpson’s 1-D diversity index value was 0.47 for outside of a MPA with 0.82 the highest index value for a site inside an MPA. Density of A. planci were found to be 12.5 per hectare, which is below outbreak densities. No significant differences were found in any metrics for inside or outside MPAs.

Since the 1960’s the crown-of-thorns starfish, Acanthaster planci¸ has devastated coral reefs. There are many competing theories about the causes for these outbreaks of A. planci. One of the leading theories is that it is an anthropogenic cause. As a result, Marine Protected Areas (MPA) may be a way to protect coral reefs from outbreaks of A. planci by removing anthropogenic effects and allowing the reef to protect itself. Coral reef health was assessed using fish population diversity, percent live coral reef coverage and density of A. planci. Lowest live coral reef coverage was 42.97% with 80.70% the highest. Highest Simpson’s 1-D diversity index value was 0.47 for outside of a MPA with 0.82 the highest index value for a site inside an MPA. Density of A. planci were found to be 12.5 per hectare, which is below outbreak densities. No significant differences were found in any metrics for inside or outside MPAs.

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