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Humans increasingly dominate Earth's natural freshwater ecosystems, but biomass production of modified ecosystems is rarely studied. We estimate potential fish total standing stock in USA reservoirs is 3.4 billion (B) kg, and approximate annual secondary production is 4.5 B kg y-1. We also observe varied and non-linear trends in reservoir fish biomass over time, thus previous assertions that reservoir fisheries decline over time are not universal. Reservoirs are globally relevant pools of freshwater fisheries, in part due to their immense limnetic footprint and spatial extent. This study further shows that reservoir ecosystems play major roles in food security and fisheries conservation. We encourage additional effort be expended to effectively manage reservoir environments for the good of humanity, biodiversity, and fish conservation.

Freshwater fisheries in developing regions provide livelihoods and nutrition for millions of people worldwide. These fisheries are frequently data poor, which limits fisheries management. The seasonal Cambodian dai platform fishery on the Tonle Sap River is one of the best monitored inland fisheries in Southeast Asia, yet catch sampling is limited and there is no fishery-independent monitoring. A monitoring system is needed to characterize fish migration and mortality, be cost effective, and be deployable in areas with minimal infrastructure. We integrated a Simrad wide-band transceiver mini echosounder (200 kHz), solar power, and an Internet of Things communications module as an autonomous, automated monitoring package for the deployment on upstream and downstream commercial fishing platforms. The solar panel and controller supply direct current power to the echosounder, communications module, and battery for power during dark hours. Echosounders are programmed to sample at 1 Hz for 15 min every hour. The communications module is a built cellular endpoint that accesses a local wireless network to transmit raw data files to a data server. Data are downloaded from the server for processing and analysis. This expandable system provides a flexible management tool that can be deployed at any location with wireless communication capability. [ABSTRACT FROM AUTHOR]

The history of freshwater fish production and consumption in Thailand were reviewed in the late 1970s. While aquaculture had a history of more than a century in the country it had only started to expand relatively recently because of the abundance of wild fish in former times. Historical aspects of freshwater capture fisheries and freshwater aquaculture in Thailand, and the development of irrigation in Central Thailand which played an important role in facilitating the development of inland aquaculture in the country were reviewed. While dam construction led to the demise of the flood plain capture fishery, it provided a controlled water supply necessary for the subsequent development of aquaculture. The study informed the development of education and research in aquaculture at the Asian Institute of Technology (AIT). More recent developments in Thai aquaculture are outlined. Malnutrition in developing countries and fish in the Thai diet at the time of the study were also reviewed. [ABSTRACT FROM AUTHOR]

Abstract Humans increasingly dominate Earth’s natural freshwater ecosystems, but biomass production of modified ecosystems is rarely studied. We estimate potential fish total standing stock in USA reservoirs is 3.4 billion (B) kg, and approximate annual secondary production is 4.5 B kg y−1. We also observe varied and non-linear trends in reservoir fish biomass over time, thus previous assertions that reservoir fisheries decline over time are not universal. Reservoirs are globally relevant pools of freshwater fisheries, in part due to their immense limnetic footprint and spatial extent. This study further shows that reservoir ecosystems play major roles in food security and fisheries conservation. We encourage additional effort be expended to effectively manage reservoir environments for the good of humanity, biodiversity, and fish conservation.

Abstract Globally there is already a lot of pressure on water resources because of climate change, economic development, as well as an increasing global populace. Many rivers originate in the mountains, where snowfall fluctuations and the global climate’s inherent unpredictability affect the hydrological processes. Climate change sensitivity has been recognized in recent years and would affect hydropower, such as humidity, cloudiness, and precipitation, that are considered; global warming emerges as one of the most important contributors to climate change. The Yangtze River supports rich biodiversity and provides important ecosystem services for human survival and development. In addition, climate changes, particularly short-term and long-term precipitation and temperature fluctuations, influence the snow regime and the hydrological development of river flow response at the basin and sub-basin scales. More precise this review focused to understand the hydropower potential, freshwater fisheries, and hydrological response of snow dynamics in snow-dominated basins.

Globally there is already a lot of pressure on water resources because of climate change, economic development, as well as an increasing global populace. Many rivers originate in the mountains, where snowfall fluctuations and the global climate's inherent unpredictability affect the hydrological processes. Climate change sensitivity has been recognized in recent years and would affect hydropower, such as humidity, cloudiness, and precipitation, that are considered; global warming emerges as one of the most important contributors to climate change. The Yangtze River supports rich biodiversity and provides important ecosystem services for human survival and development. In addition, climate changes, particularly short-term and long-term precipitation and temperature fluctuations, influence the snow regime and the hydrological development of river flow response at the basin and sub-basin scales. More precise this review focused to understand the hydropower potential, freshwater fisheries, and hydrological response of snow dynamics in snow-dominated basins. [ABSTRACT FROM AUTHOR]

Recreational fisheries represent a socially, ecologically, and economically significant component of global fisheries. The U.S. Inland Creel and Angler Survey Catalog (CreelCat) database includes inland recreational fisheries survey data across the United States to facilitate large‐scale analyses. However, because survey methods differ, a statistical method capable of integrating these surveys is necessary to assess patterns and relationships across regions. Here, we developed a hierarchical generalized linear mixed modeling approach to estimate the relationship between daily recreational fisheries catch and effort based on waterbody, socio‐economic, and ecological covariates. We applied this approach to CreelCat data on lentic waterbodies and found that recreational fisheries catch and effort were non‐linearly related (i.e., catch per unit of effort declined as effort increased), where effort varied regionally and by waterbody area, median county age, and distance to nearest primary road. This modeling approach could be used to inform data‐poor regions or waterbodies, make comparisons across spatial scales, and, with the inclusion of socio‐economic and ecological factors, inform management techniques in an era of shifting demographics and landscapes. [ABSTRACT FROM AUTHOR]

The history of freshwater fish production and consumption in Thailand were reviewed in the late 1970s. While aquaculture had a history of more than a century in the country it had only started to expand relatively recently because of the abundance of wild fish in former times. Historical aspects of freshwater capture fisheries and freshwater aquaculture in Thailand, and the development of irrigation in Central Thailand which played an important role in facilitating the development of inland aquaculture in the country were reviewed. While dam construction led to the demise of the flood plain capture fishery, it provided a controlled water supply necessary for the subsequent development of aquaculture. The study informed the development of education and research in aquaculture at the Asian Institute of Technology (AIT). More recent developments in Thai aquaculture are outlined. Malnutrition in developing countries and fish in the Thai diet at the time of the study were also reviewed. [ABSTRACT FROM AUTHOR]

Freshwater fisheries and biodiversity have substantial economic, socio-cultural, and ecological value, but face severe and mounting anthropogenic threats. Canada's freshwater fisheries are not exempt from this, and provide excellent opportunities to better understand these overlooked and undervalued systems. Using expert and chain-referral sampling, we surveyed practitioners from across Canada about the management of freshwater fisheries. We used a mixed methods approach to identify and describe in detail many important aspects of the above processes, including 10 persistent and innate challenges in (1) bureaucratic sprawl, (2) lack of priority, (3) scope, (4) competing interests, (5) political inconstancy, (6) socio-ecological complexity, (7) limited tools, (8) geographies and scale, (9) reactivity, and (10) intersectoral frictions. Many of these challenges defy conventional problem solving (e.g., advocacy, basic science), leading to chronic incapacity and triage management in some freshwater fisheries. We highlight opportunities to increase management capacity, using innovation where conventional solutions fall short (e.g., using novel technologies to increase management scope). Achieving sustainability in Canadian freshwater fisheries will require ingenuity and supportive contributions beyond those that currently exist. [ABSTRACT FROM AUTHOR]

The government has supported the development of freshwater fisheries or local fisheries via the Fisheries Statistics Group, Fisheries Development Policy and Planning Division of the Department of Fisheries. In the development of local areas, freshwater fishing is encouraged for a group of 3 species of fish: Tilapia, Catfish and Tapia. The problems encountered by freshwater fisheries are water quality and feeding procedures in freshwater fisheries that provide food with not actual proportional. Consequently there are increasing labor costs and deteriorating water quality. We found a way to manage fish feeding automatically and check water quality through the application of MQT technology to manage work and to monitor the data to suit freshwater fishing, providing quality of growth and proper control of the amount of food supplied, thereby reducing food costs. The research was divided into two parts: hardware and software. Hardware was an M.C.U. node with a relay used to control the motor. In addition, there was a PH sensor module and waterproof temperature sensor. Python programming served as a platform for developing applications used to communicate with users. The results showed that Farmers were satisfied because the good quality of water provided survival rates of catfish in the nursery which increased from the original 92% to 100% after the trial and also reduced the labor cost of taking care of the nursery catfish for 1,725 baht/month. This was possible because information can be checked and controlled through an application as can the remaining time for other occupations. [ABSTRACT FROM AUTHOR]

The history of freshwater fish production and consumption in Thailand were reviewed in the late 1970s. While aquaculture had a history of more than a century in the country it had only started to expand relatively recently because of the abundance of wild fish in former times. Historical aspects of freshwater capture fisheries and freshwater aquaculture in Thailand, and the development of irrigation in Central Thailand which played an important role in facilitating the development of inland aquaculture in the country were reviewed. While dam construction led to the demise of the flood plain capture fishery, it provided a controlled water supply necessary for the subsequent development of aquaculture. The study informed the development of education and research in aquaculture at the Asian Institute of Technology (AIT). More recent developments in Thai aquaculture are outlined. Malnutrition in developing countries and fish in the Thai diet at the time of the study were also reviewed.

Enhancing understanding of community assembly rules hinges on shared conceptualizations that operate across scales and levels of ecological organization. Knowledge of the biogeography of life‐history strategies is especially limited but crucial for building fundamental information on the relationships between trait diversity and species richness.The goals of this study were to (i) demonstrate how life histories can be classified using a previously identified triangular continuum of evolutionary trade‐offs; (ii) test whether spatial and temporal heterogeneity in species abundances is linked to life‐history strategy; (iii) compare species‐area relationships across the primary life‐history strategist groups and (iv) explore how species life‐history niche spaces are shaped by ecosystem size and landscape architecture.Fish communities were sampled in 40 lakes that varied widely in volume; 11 lakes were sampled annually for 28 or 42 years. Seventy‐one species were classified as equilibrium, periodic or opportunistic strategists, and species‐area curves were quantified and compared among strategy types.As predicted by life‐history theory, relative abundances of opportunistic strategists were extremely variable over space and time, whereas abundances of equilibrium and periodic strategists were more stable. Small lakes were often dominated by only one species, usually an opportunistic strategist. Species richness increased with ecosystem size, but larger ecosystems were increasingly inhabited by equilibrium, and then, periodic strategists. Richness of periodic species increased with ecosystem size at a faster rate compared with opportunistic species showing that colonization‐extinction points fundamentally vary by strategy. Similarly, life‐history niche space increased with ecosystem size in accord with species‐area relationships but showed saturation behaviour. Niche space became increasingly crowded in large lakes, particularly in lakes with higher hydrologic connectance.Ecosystem size mediates the assembly of communities through effects on environmental stability, hydrology and life‐history filtering. This finding provides novel insights into community assembly at multiple scales and has broad conservation applications. Because ecosystem size filters towards orthogonal and inverse life histories, conservation actions (e.g. fish stockings) that do not consider life‐history and community filtering rules will probably fail. [ABSTRACT FROM AUTHOR]

Environmental DNA methods have emerged as a promising tool in fish diversity studies and fishery management in various aquatic ecosystems. However, eDNA metabarcoding of fish communities in small hydropower dam reservoirs has received limited attention. In this study, we tested whether eDNA metabarcoding was an appropriate approach for the characterization of fish communities and fishery stock assessment by comparing its results with combined capture-based fishing methods and hydroacoustic surveys, which involved species detection and abundance/biomass evaluation. Our results indicated that the species detection performance of eDNA metabarcoding was basically similar to that of traditional capture-based fishing gear. However, it was also noteworthy that the eDNA method failed to cover all species detected by capture-based method, although some additional species were found. Besides, although we observed a significant correlation between site occurrence and sequence abundance for fishes, an effort to quantitatively establish a correlation between eDNA sequence counts and fish abundance/biomass was unsuccessful. Therefore, our study suggested that eDNA metabarcoding was an important supplementary tool to traditional capture-based fishing methods for the investigation and biomonitoring of fish diversity in small hydropower dam reservoirs. Further studies on the mechanisms of eDNA production, persistence, transportation and degradation in reservoirs might facilitate the interpretation of fish abundance and biomass from eDNA data.

Environmental DNA methods have emerged as a promising tool in fish diversity studies and fishery management in various aquatic ecosystems. However, eDNA metabarcoding of fish communities in small hydropower dam reservoirs has received limited attention. In this study, we tested whether eDNA metabarcoding was an appropriate approach for the characterization of fish communities and fishery stock assessment by comparing its results with combined capture-based fishing methods and hydroacoustic surveys, which involved species detection and abundance/biomass evaluation. Our results indicated that the species detection performance of eDNA metabarcoding was basically similar to that of traditional capture-based fishing gear. However, it was also noteworthy that the eDNA method failed to cover all species detected by capture-based method, although some additional species were found. Besides, although we observed a significant correlation between site occurrence and sequence abundance for fishes, an effort to quantitatively establish a correlation between eDNA sequence counts and fish abundance/biomass was unsuccessful. Therefore, our study suggested that eDNA metabarcoding was an important supplementary tool to traditional capture-based fishing methods for the investigation and biomonitoring of fish diversity in small hydropower dam reservoirs. Further studies on the mechanisms of eDNA production, persistence, transportation and degradation in reservoirs might facilitate the interpretation of fish abundance and biomass from eDNA data. [ABSTRACT FROM AUTHOR]

Beyşehir Lake, located in one of the important karstic discharge basins of the Anatolian Plate, is Turkey's largest freshwater lake with a surface area of 650 km2, and is a very important wetland in terms of bio-ecological, socio-economic, and cultural aspects. Although the first records on Beyşehir Lake fishery date back to the 1910s, the first scientific findings on fisheries began in the 1950s. Although it is challenging to reach reliable data about the fishery of Lake Beyşehir, the main processes that have been effective in fishing from the 1950s to the present are: i) used fishing gear and methods, ii) changes in the trophic structure of the lake, iii) foreign fauna elements entering the lake, iv) the lake water level changes, v) fishermen's socio-economic and awareness level, vi) fisheries management strategies. The lake's catch yield was nearly 3 kg/ha in the 1950s, and it was determined as 13.34 kg/ha in 2021. While there have been significant changes in the fauna in the intervening time, it has been determined that there has been a substantial increase in the number of fishermen with the increasing amount of catch. Today, 23 fish species, 14 of which are endemic, live in the lake, which is at the mesotrophic-eutrophic level in terms of trophic status. The average catch amount between 2010 and 2021 was 669.051 kg/year. 67.41% of this amount was composed of Carassius gibelio (Prussian carp), 20.17% of Sander lucioperca (pike-perch), and 12.42% of Cyprinus carpio (carp). In 2021, the last fishing season, 75.41% of the caught species were Prussian carp, 21.47% pike-perch, and 3.11% carp. 385 fishermen are actively fishing in the lake, and according to the data of 2021, it has been determined that the fishermen have earned 13,970 TL/year in return for 2.252 kg/year of catch. As another result of this study, it has been understood that the most significant factor in the fishing ecosystem of Beyşehir Lake is untimely and excessive fishing. [ABSTRACT FROM AUTHOR]

Aquatic ecosystems are strongly affected by global change. Fishers hold local ecological knowledge (LEK) that is especially relevant for improving our understanding of aquatic ecosystems that experience major environmental changes while also providing crucial ecosystem services. This research explores the perceptions of the ecological changes in Laguna Lake (Philippines) among local fisherfolks. In 2019, we conducted 30 semi-structured interviews with fisherfolks with up to 60 years' experience. They reported catching 31 fish species and one shrimp genus as a staple food and income source, with more than one-third of the species being exotic or introduced. The fisherfolks noted repeated fish kill events and dramatic changes in their catch such as fewer and smaller fish. Also noticeable were the widespread catch of knifefish, a comparably newly introduced species, and the fact that all native fish species were reported to be less often caught now than in the past. This included the reduced catch of talilong (mullet), dalag (snakehead), and ayungin (silver perch). Locals emphasized various drivers behind these changes, which are linked to one another in complex interrelationships. Invasive species, the deterioration of fish habitats, and increased water turbidity were cited as the main drivers. Interviewees highlighted an additional link between declining catches and the loss of aquatic plant diversity, which has been understudied in Laguna Lake and has not been the focus of regional policy efforts. The empirical evidence provided by the fisherfolks enhances earlier existing scientific evidence of this aquatic ecosystem as well as highlights the importance of contributions coming from different knowledge systems. [ABSTRACT FROM AUTHOR]

Spawning of invasive smallmouth bass (Micropterus dolomieu) was studied in 2020 and 2021, in Lake Nojiri, Nagano, Japan. Male smallmouth bass began nest construction once water temperatures reached 14°C, and eggs progressed to fry dispersal in approximately 2 weeks. The main spawning season was in late May through early June, with a smaller second peak of nests in late June through early July. Nests were constructed primarily under dock cover, and nest size and depth were positively correlated with male body size. Of the nests that received eggs, nearly all progressed successfully to fry dispersal. Time lapse videos of male guarding behavior revealed that as nests progressed, males rotated less and were suspended off the bottom substrate. Similarly, the presence of egg predators was determined by experimental removal of guarding males. Freshwater gobies (Rhinogobius kurodai) were the only egg predators observed and arrived on all nests in the egg stage. However, only a handful of gobies visited each nest, the total number of eggs predated was low, and eggs or alevins in the progressed stage were rarely predated. These results indicate that in Lake Nojiri, smallmouth bass spawning is highly successful and egg predators appear to have minimal effect on egg survival. The stable smallmouth bass fishery without stocking at this lake is likely a product of these favorable spawning conditions. The lack of native egg predators may also be a driving factor in the continued spread of smallmouth bass throughout Japan. [ABSTRACT FROM AUTHOR]

Stream fishes are increasingly threatened by consequences of climate change that will alter stream habitats. Conservation of stream ecosystems will be more effective if management actions retain or restore essential structures and functions that promote ecosystem resilience to disturbance.This study developed a method for assessing the resilience of stream fish habitat in Michigan, USA. Three sub‐indices comprising different components of resilience were derived using information on natural landscape features, human impacts and habitat heterogeneity. These sub‐indices were combined into a single overall index to broadly characterize resilience.Mapping sub‐indices show that stream resilience based on natural features varies across Michigan, whereas resilience reduced by human impacts decreases from north to south, corresponding to patterns in human population density and land use. Higher stream resilience occurs in the Upper and Northern Lower Peninsulas of Michigan which have more natural features and fewer human impacts, although some resilient streams also occur in the Southern Lower Peninsula, suggesting that there are opportunities in every part of the state for protecting resilient streams.Resilience index scores combined with modelled distributions of a fish species of conservation importance show locations where specific conservation action would be most effective in protecting or improving habitat for this species.The assessment of Michigan stream resilience provides new information for supporting conservation strategies and action in relation to expected changes caused by climate change. It also offers an approach that can be applied in other regions. [ABSTRACT FROM AUTHOR]

Inland fisheries make substantial contributions to food security and livelihoods locally, regionally, and globally but their conservation and management have been largely overlooked by policy makers. In an effort to remedy this limited recognition, a cross-sectoral community of scientists, practitioners, and policy makers from around the world convened a high-level meeting in 2015 at the Food and Agriculture Organization of the United Nations headquarters in Rome, Italy to develop recommendations for sustainable inland fisheries management. This meeting resulted in the production of the Rome Declaration, outlining ten key steps needed to achieve responsible inland fisheries. When the Ten Steps were conceived, they were framed in a global context because inland fisheries around the world face similar challenges, and it was hoped that these large-scale and ambitious steps would draw the attention of regional or international bodies for greater investment in their proper management. Most inland fisheries, however, are managed at a local (often community, watershed, or waterbody) scale with the "on-the-ground" practitioners, managers, assessment biologists, and stewardship officers responsible for achieving the promise of the Ten Steps. Here, we reflect on the relevance of the Ten Steps to practitioners using six regional case studies from around the globe (North America, South America, Europe, Asia, Australia, and Africa) to identify the extent to which existing efforts align with the Ten Steps and where there are opportunities to do more. Learning what is effective from local/regional actions should better inform a more global "action plan" and provide tangible guidance for implementation recognizing that global guidance needs to be informed by and acted upon by local practitioners. We conclude by considering the common challenges, synergies, and other emergent properties that arise from these case studies, and use these as a path forward to advancing responsible management of inland fisheries through the Rome Declaration. Of particular importance is the need to balance the high-level aspirational goals of the Ten Steps with the local cultural, socio-economic, and institutional realities that ultimately influence how humans interact with fisheries resources and aquatic ecosystems. This assessment provides valuable information on how to refine and implement the Ten Steps recognizing that success will require coordinated efforts among on-the-ground practitioners, scientists, stakeholders, rightsholders and international decision makers. [ABSTRACT FROM AUTHOR]

The recent increase in Cormorant numbers in the UK and the increasing use of inland feeding sites by the birds have created conflicts at many freshwater fisheries. Information on the prey composition of Cormorants foraging at such sites is important in understanding these conflicts and in providing a sound basis for management. Two subspecies of Great Cormorant, the continental subspecies Phalacrocorax carbo sinensis and the Atlantic subspecies Phalacrocorax carbo carbo occur in the UK and forage sympatrically. This study presents information on the winter diet of over 1400 Cormorants shot at inland fishery sites over an eleven-year period. A wide range of prey species were identified, but five fish species compromised almost 80% of the prey items recorded by number, and most prey items were small (≤10 cm). Dietary differences, in terms of the species, sizes and number of fish consumed, were apparent between birds of different sex and subspecies, consistent with the differing sizes of the birds. The largest birds (male P. c. carbo) tended to consume fewer, larger fish and the smallest birds (female P. c. sinensis) more, smaller items. Bird size also appears to influence foraging site selection, with male P. c. carbo more likely to forage on fisheries, such as put-and-take trout fisheries, where larger prey items were available. [ABSTRACT FROM AUTHOR]

The time-tested Indigenous fishing knowledge (IFK) of Fiji and the Pacific Islands is seriously threatened due to the commercialization of fishing, breakdown of traditional communal leadership and oral knowledge transmission systems, modern education, and the movement of the younger generations to urban areas for work and/or study. Consequently, IFK, which has been orally transmitted for generations, has either been lost, not learned by the current generation, or remains undocumented. This study focuses on the critical need to conserve and include IFK as a basis for assessing the conservation status of ecologically and culturally keystone fisheries species as a basis for planning site-specific management of marine and freshwater fisheries in Fiji and the Pacific Islands. The study reviews studies of the last two and a half centuries on IFK from Fiji and elsewhere in the small oceanic islands of the Pacific, as a basis for the conservation, documentation and intergenerational transfer of this knowledge as the foundation for sustainable fisheries management. The study also reviews: the nature and conservation status of IFK, itself; and the conservation status of species considered to be of particular ecological and cultural importance; reasons for the loss of species/taxa and associated knowledge and practices; and actions that can be taken to address this loss.

Hydroelectric dams often have significant impacts on freshwater fisheries. Major impacts are known to be driven by changes in river hydrology and fish ecology, but the role of governance arrangements in mitigating or exacerbating fisheries impacts from hydropower development is less understood. This study presents an analysis of stakeholder perceptions about the effects of hydroelectric dam implementation on fisheries governance arrangements in the Madeira River basin, Brazil. Semi-structured interviews were conducted with 50 stakeholders representing the fishers and fish traders, government, non-governmental organizations, and the private sector. Fishers, non-governmental, and private sector agents perceived hydropower development to be the strongest factor driving fisheries decline or change over the past 10 years, while government staff perceived overfishing to be an equally or even more important factor. Most stakeholders affirmed that fisheries governance arrangements have weakened in the face of hydropower development, and that these arrangements have been insufficient to effectively mitigate or compensate for negative impacts on fisheries. Fishers, non-governmental and private sector agents saw lack of opportunities to participate in fisheries governance as a major contributing factor, while government staff emphasized lack of qualified personnel, lack of trust between agencies, and control over the decision-making process held by hydropower companies. Perspectives on other implications of governance arrangements were shared across stakeholder groups. These included increased conflicts; lack of interaction and coordination between agencies; the fragility of fishers’ social organization; lack of trust and reciprocity between organizations; and power imbalances between stakeholders. The results show that hydropower development impairs and changes relationships between diverse players involved in fisheries governance, which can exacerbate existing weaknesses and negatively affect fishery sustainability. Drawing from the perspectives and comments of the various stakeholders who participated in the study, we provide recommendations to improve freshwater fisheries governance in the Madeira River basin and in the Brazilian Amazon.

The fisheries of Lake Tanganyika play an important role in food security in Central and Eastern Africa. Conservation of these valuable fish stocks will benefit from documenting the ideas, opinions and observations of stakeholders. Knowledge of the perceptions and an understanding of the concerns and struggles of stakeholders of these fisheries can provide policy-makers with recommendations for more suitable fisheries management. We did 1018 interviews with stakeholders, in one close-ended and three semi-open ended surveys. Factor analysis revealed seven clusters of opinions. Linear-mixed effects models identified common grounds and differences in opinions between groups of stakeholders about strategies in fisheries management. Stakeholders of the fisheries indicated challenges due to weather or climate variability, a noticeable decrease in fish abundance and size, and an increase in the price of fish. Fishermen experienced a lack of safety on the lake, including aggression and dangerous weather conditions, and hardly had access to safety gear and infrastructure. Landing site officials, state employees who monitor the beaches, mentioned capture of juveniles and declining catch-rates as the biggest threats to the fisheries. None of the groups of stakeholders attributed the problems in the fisheries to overfishing or overpopulation. We found similarities in opinions over a wide range of stakeholder groups, with many stakeholders asking for better and fair enforcement of existing legislation. State employees were more positive than the other groups towards creating more strict regulation of the fisheries. The results presented offer focuspoints for policy-makers to improve the management of the Lake Tanganyika pelagic fisheries. [ABSTRACT FROM AUTHOR]

Exopalaemon modestus (Heller, 1862) and Macrobrachium nipponensis (De Haan, 1840) (Palaemonidae) are ecologically and commercially important fishery resources in the Three Gorges Reservoir (TGR), China, and co-occur in demersal habitats. Little information is available on their biology. We compared the reproductive traits of both species on the upper, middle, and lower sections of the TGR. Both species differed in mean size at maturity, which increased from upper to middle and lower sections. Sex ratios were significantly biased toward females, but no significant differences were observed among the three sites for either species. Both species displayed an obvious trade-off between embryo size and fecundity, with the size of embryos being the smallest but with the highest fecundity at the upper section, followed by the middle and lower sections. Exopalaemon modestus spawned from early April to late September, with a peak in May and June, whereas M. nipponensis spawned from late April to early October with a peak in June and July. The spatially distinct reproductive traits, which were concordant across species, are likely related to differences in habitat characteristics such as water flow. We suggest that management strategies should account for the reproductive biology of the two species in order to maintain a sustainable fishery in the reservoir. [ABSTRACT FROM AUTHOR]

The role of aquatic resources to food security is both promising and constrained since the global seafood consumption is increasing while marine fisheries approach the limit of what it can produce. In Sweden, the seafood consumption per capita is higher than the European and world average but the current dietary advice is to increase consumption. Freshwater fisheries have in general been paid less attention in food security discussions. Carp fishes (Cyprinidae) in Sweden have lost their historical value and are currently, both understudied and underutilized. Here we use a combined environmental assessment approach to examine the environmental sustainability of current and potential cyprinid fisheries. We found that current commercial fisheries for Swedish cyprinids in lakes have an average carbon footprint of 0.77 kg CO2e per kg of edible product, substantially smaller than most of the popular marine and terrestrial protein sources consumed in Sweden today. This could be even lower if cyprinid resources were better utilized than currently. The cyprinids however exhibited different vulnerability to fishing pressure and are today associated with data deficiencies. Hence, it is currently uncertain how much food for human consumption they can contribute to. Improved consumer interest and management attention is needed, but to the Swedish diet, cyprinids offer a promising opportunity for future more sustainable and nutritious food systems. [ABSTRACT FROM AUTHOR]

Inland capture fisheries provide food for nearly a billion people and are important in the livelihoods of millions of households worldwide. Although there are limitations to evaluating many of the contributions made by inland capture fisheries, there is growing recognition by the international community that these services make critical contributions, most notably to food security and livelihoods in rural populations in those low‐income countries with extensive freshwater resources. With the increasing appreciation of the key role of inland fisheries to the health and well‐being of human populations globally, the Food and Agriculture Organization of the United Nations and Michigan State University convened the 2015 global conference, Freshwater, fish, and the future – cross‐sectoral approaches to sustain livelihoods, food security, and aquatic ecosystems. What emerged from the interactions between inland fisheries' scientists, resource managers, policymakers and community representatives from across the world was a forward‐looking call to action culminating with the 2015 Rome Declaration "Ten Steps to Responsible Inland Fisheries" (FAO & MSU, Rome declaration on responsible inland fisheries: 5735E/1/06.16). Four years after this landmark conference and declaration, we seek to advance discussion on the "Ten Steps," namely what successful implementation looks like, assess current examples of implementation, suggest potential signals of progress and provide some specific, indicative examples of progress for each step. While there are promising signs of progress, we conclude that there remains a strong need to galvanize momentum for sustained action to ensure that inland fish and fisheries are accounted for and incorporated into broader water resource management discussions and frameworks. [ABSTRACT FROM AUTHOR]

• Stage structured mortality rates result from fish life history and human behavior. • Large females in sexually dimorphic species are favored by release of large fish. • Relaxed regulations may result in lower adult female mortality rates via increased male harvest. • Integrating life history and human behavior into models provides insight for modern conservation. Human behavior shapes modern ecosystems but is difficult to parse into parameters for ecological models. We used Bayesian models of human behavior, a stage-structured population model, and a novel mortality integration approach to ask how human decisions affect animal population dynamics and conservation outcomes in the context of recreational fishing. Walleye (Sander vitreus) are a broadcast-spawning freshwater fish with large, slow-maturing females and small, fast-maturing males. We observed that simpler and less restrictive fishing regulations outperformed more complex and stricter regulations at conserving equilibrium adult female abundance and overall population abundance while still facilitating large harvests. This outcome was possible because angler behavior within the least restrictive regulation concentrated harvest on juveniles and adult males. Our findings indicate that, counter to intuitive expectations, moderate regulations can acheive conservation objectives when we account for the interaction of regulatory policy, human behavior, and animal life history. We suggest that integrating models of human behavior with models of animal life history and population dynamics will provide essential insights for conservation in ecosystems increasingly shaped by human decisions. [ABSTRACT FROM AUTHOR]

In the New Zealand landscape, the mahika kai sites (resource gathering areas) are marked through place names, which act as central reference points (whai take) for a wider ecosystem catchment area and indicate changes over time. The traditional ecological knowledge, awakened through place names, informs and influences the way Māori realise cultural, social, environmental, and economic aspirations and practices (past and present). This paper will draw from a research project in Te Wai Pounamu (South Island), New Zealand that utilises traditional ecological knowledge (TEK) surrounding the place name, Matainaka, which indicate places where Kāi Tahu (South Island Māori tribal group) gathered whitebait (īnaka, Galaxias maculatus): an important fresh water species. A major focus of the research project is the knowledge around socio-cultural tipping points that will impact directly on the future cultural, social and economic sustainability within a specific catchment location, the Waikōuaiti River. The river has spawning and fishing sites for the īnaka mahika kai and comes under the mana whenua (recognised traditional authority) of the Māori tribal group, Kāti Huirapa Rūnaka ki Puketeraki. Traditional ecological knowledge kōrero (speech) explains the importance of Matainaka and its contribution to the surrounding catchment area, and - in contemporary times - works alongside that of scientific knowledge. The project merged TEK and science to find ways to improve future planning and adaptation for habitat restoration and modification, and to lessen impacts on īnaka spawning sites from the expected impacts of climate change. [ABSTRACT FROM AUTHOR]

Freshwater social-ecological systems are shaped by site-specific characteristics, environmental change and annual fluctuations, and the actions of resource users and managers. Our primary aim is to analyze the relative effects of these multifacted forces on fishery productivity and biodiversity using the case of community-managed protected areas within Cambodia's rice field fisheries, known as community fish refuges. Our secondary aim is to take advantage of fixed-effects regression models, a rigorous approach that is common in other disciplines, yet novel to analysis of social-ecological system productivity, and allows comparison of each site to itself across time using observational data. We analyze the relative associations of site characteristics, annual fluctuations, biophysical modifications (e.g., deepening, creation of inlet/outlets, etc.), and governance capacity (i.e., community committee meeting intensity, fundraising to support illegal fishing patrols, etc.) with fish biomass and biodiversity within 40 refuges over three years. We find that seasonal and site-specific effects within this system relate strongly to biomass and species richness patterns. We also find an association between biomass and biodiversity and some elements of governance capacity building. Our findings suggest that in this setting solutions tailored and responsive to the local context may be most appropriate given the strong interannual and site-specific drivers. Methodologically, the dynamism and site specificity of such systems befits within-site comparisons over long time horizons to appreciate the factors that drive biomass and biodiversity. [ABSTRACT FROM AUTHOR]

Prochilodus lineatus (Val.) is one of the main target species of South American freshwater fisheries. The following null hypotheses regarding juvenile recruitment of P. lineatus were tested: (a) recruitment is not determined by variations in larval abundance and (b) recruitment is not determined by variations in discharge. For this purpose, variations in abundance of larvae in main channel drift and monthly captures of juveniles in a floodplain lake of the River Paraná were examined weekly between 2009 and 2016. Mean annual abundances of larval densities and CPUE of juveniles were correlated with a set of hydrometric variables. A positive correlation was found between the abundance of juveniles with high and persistent flood pulses. By contrast, larval abundance was not correlated with juvenile abundance. Pronounced contrast was found in the recruitment of P. lineatus between years of high and low discharge, which supports the hypothesis that floods are the main determining factor for recruitment of this species. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agricultural Economics & Social Sciences is the property of Egyptian National Agricultural Library (ENAL) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: The long‐term evolutionary effects of fishing on maturation schedules can depend on gear type, the shape of the gear type's size‐selectivity function, and the size and age structure of a population. Our goal was to better understand how environmentally induced differences in somatic growth influence the evolutionary effects of size‐selective fisheries, using lake whitefish (Coregonus clupeaformis) in Lake Huron as a case study. Using a state‐dependent optimization model of energy allocation parameterized for lake whitefish, we show that fishing with gill nets (bell‐shaped selectivity) and trap nets (sigmoid‐shaped selectivity) can be potent agents of selection on size thresholds for maturity. Compared to trap nets and large mesh (114 mm) gill nets, small mesh (89 mm) gill nets are better able to buffer populations from fishing‐induced evolution by safeguarding large, fecund fish, but only when overall fishing mortality is low and growth rates sufficiently fast such that fish can outgrow vulnerable size classes. Regardless of gear type, and all else being equal, high fishing mortality in combination with low growth rates is expected to intensify the long‐term evolutionary effects of fishing. [ABSTRACT FROM AUTHOR]

We analyze the invisibility of fisheries and inadequacy of fishers’ participation in the process of hydropower development in the Amazon, focusing on gaps between legally mandated and actual outcomes. Using Ostrom’s institutional design principles for assessing common-pool resource management, we selected five case studies from Brazilian Amazonian watersheds to conduct an exploratory comparative case-study analysis. We identify similar problems across basins, including deficiencies in the dam licensing process; critical data gaps; inadequate stakeholder participation; violation of human rights; neglect of fishers’ knowledge; lack of organization and representation by fishers’ groups; and lack of governmental structure and capacity to manage dam construction activities or support fishers after dam construction. Fishers have generally been marginalized or excluded from decision-making regarding planning, construction, mitigation, compensation, and monitoring of the social-ecological impacts of hydroelectric dams. Addressing these deficiencies will require concerted investments and efforts by dam developers, government agencies and civil society, and the promotion of inter-sectorial dialogue and cross-scale participatory planning and decision-making that includes fishers and their associations. [ABSTRACT FROM AUTHOR]

Freshwater social-ecological systems are shaped by site-specific characteristics, environmental change and annual fluctuations, and the actions of resource users and managers. Our primary aim is to analyze the relative effects of these multifacted forces on fishery productivity and biodiversity using the case of community-managed protected areas within Cambodia's rice field fisheries, known as community fish refuges. Our secondary aim is to take advantage of fixed-effects regression models, a rigorous approach that is common in other disciplines, yet novel to analysis of social-ecological system productivity, and allows comparison of each site to itself across time using observational data. We analyze the relative associations of site characteristics, annual fluctuations, biophysical modifications (e.g., deepening, creation of inlet/outlets, etc.), and governance capacity (i.e., community committee meeting intensity, fundraising to support illegal fishing patrols, etc.) with fish biomass and biodiversity within 40 refuges over three years. We find that seasonal and site-specific effects within this system relate strongly to biomass and species richness patterns. We also find an association between biomass and biodiversity and some elements of governance capacity building. Our findings suggest that in this setting solutions tailored and responsive to the local context may be most appropriate given the strong interannual and site-specific drivers. Methodologically, the dynamism and site specificity of such systems befits within-site comparisons over long time horizons to appreciate the factors that drive biomass and biodiversity.

Copyright of Journal of Agricultural Science & Technology (1008-0864) is the property of Journal of Agricultural Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We analysed the effects of decadal and annual hydrologic fluctuations on freshwater fisheries catches in the Middle Paraná River for a period of six decades from the 1930s to the 1980s. The climatic fluctuations in this period strongly affected the hydrology of the Middle Paraná River and the characteristics of its flow regime. The magnitude of floods as well as maximum, minimum and mean water levels increased progressively from 1930s until the 1980s concomitantly with increasing frequency and intensity of El Niño Southern Oscillation events that resulted in differentiation of distinct hydrological periods. The flood pulses were significantly more frequent and of greater magnitudes during the 1970s and 1980s. These large floods resulted in increased commercial fish catches in the 1980s, possibly because of enhanced recruitment. Specifically, large floods increased the commercial fish catches 2 years later. This effect was stronger for species that use floodplain habitats as areas of reproduction and larval nurseries, such as Prochilodus lineatus. We conclude that the natural flow regime of the Paraná River and perhaps other large subtropical rivers must be preserved in order to sustain their productive fisheries. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This work deals with all the relevant statistic data regarding fisheries of Republic of Croatia, including freshwater fisheries data (aquaculture of fish and other aquatic organisms, commercial and sports fisheries), marine fisheries data (mariculture, commercial fisheries, small–scale fisheries and processing of fish and other marine organisms), as well as data about import and export of fish and fish products and the data about financial subventions in fisheries. The total freshwater fish production in 2007 was 5,797 tons (4,151 tons of warm–water species and 1,646 tons of cold–water species). Total areas and production areas in 2007 was 5,558.66. Total catch of freshwater fish in 2007 was 697 tons. The total marine fish species production in 2007 was 4,000 tons, production of tuna 4,180 tons, mussels 3,000 tons and oysters 1,000,000 pieces. The catch of marine fish was increased by 6.09% comparing to 2006 (increase was noticed for white and blue fish species). During 2007 there were no significant changes regarding the number of commercial fishermen comparing to the last two years, while the number of small–scale fishermen increased 0.4 % comparing to the last year. The total production of fish products in 2007 was 15,349 tons, which is 11.6 % less comparing to 2006.

This work deals with all the relevant statistic data regarding fisheries of Republic of Croatia, including freshwater fisheries data (aquaculture of fish and other aquatic organisms, commercial and sports fisheries), marine fisheries data (mariculture, commercial fisheries, small–scale fisheries and processing of fish and other marine organisms), as well as data about import and export of fish and fish products and the data about financial subventions in fisheries. Regarding aquaculture (freshwater fish farming) in 2005 there have been noticed production increase in coldwater fish species. The total freshwater fish production in 2006 was 6,328 tons (4,599 tons of warm–water species and 1,729 tons of cold–water species). Total areas and production areas were decreased comparing to 2005 in all categories of production areas. Total catch of freshwater fish in 2006 was 674 tons. The total marine fish species production in 2006 was 3,500 tons, production of tuna 6,700 tons, mussels 3,500 tons and oysters 1,000,000 pieces. The catch of marine fish was increased by 9.21% comparing to 2005 (increase was noticed for white and blue fish species). During 2006 there were no significant changes regarding the number of commercial fishermen comparing to the last two years, while the number of small–scale fishermen decreased 1% comparing to the last year. The total production of fish products in 2006 was 17,362 tons, which is 2.46% more comparing to 2005.

This work deals with all the relevant statistic data regarding fisheries of Republic of Croatia, including freshwater fisheries data (aquaculture of fish and other aquatic organisms, commercial and sports fisheries), marine fisheries data (mariculture, commercial fisheries, small–scale fisheries and processing of fish and other marine organisms), as well as data about import and export of fish and fish products and the data about financial subventions in fisheries. Regarding aquaculture (freshwater fish farming) in 2005. there have been noticed slight production increase (both warmwater and coldwater fish species). The total freshwater fish production in 2005. was 6,199 tons (4,776 tons of warm–water species and 1,423 tons of cold–water species). Total areas and production areas were decreased comparing to 2004. (in all categories of production areas except for consum–fish production areas, where a slight increase has been noticed). Total catch of freshwater fish in 2005. was 656 tons. The total marine fish species production in 2005. was 3,000 tons, production of tuna 4,000 tons, mussels 2,500 tons and oysters 800,000 pieces. In mariculture sector there has been noticed the biggest increase in fish–fry production (43.39% comparing to 2004., in 2005. it was 10,000,000 pieces). The catch of marine fish was increased by 8.50% comparing to 2004. (increase was noticed for white and blue fish species). During 2005. there were no significant changes regarding the number of commercial fishermen comparing to the last two years, while the number of small–scale fishermen decreased 3.80% comparing to the last year. The total production of fish products in 2005. as 16,945 tons, which is 31.65% more comparing to 2004. In this sector the most significant is the increase of salted fish production, which was 56.11% more than 2004. The value of import in 2005. was higher than the value of export, which represents the only exception in last decade. The capital investments model is most similar to the financial subventions model which is applied in EU countries, and in 2004. there have been 20.44% more financial means payed for this purpose.

This work deals with all the relevant statistic data regarding fisheries of Republic of Croatia, including freshwater fisheries data (aquaculture of fish and other aquatic organisms, commercial and sports fisheries), marine fisheries data (mariculture, commercial fisheries, small–scale fisheries and processing of fish and other marine organisms), as well as data about import and export of fish and fish products and the data about financial subventions in fisheries. Regarding aquaculture (freshwater fish farming) in 2004 there have been noticed slight changes comparing to 2003. The total freshwater fish production in 2004 was 5,618 tons (4,259 tons of warm–water species and 1,359 tons of cold–water species). Total areas and production areas were increased comparing to 2003 (total areas 1.94% and production areas 5.42%). Total catch of freshwater fish in 2004 was 567 tons. The total marine fish species production was increased cca. 20% comparing to 2003. Mussels farming, which is slightly increasing since 1999, during 2004 was decreased, while oysters farming were stagnating. The catch of marine fish was increased by 9.74% comparing to 2003. The biggest increase is noticed regarding catch of demersal and other fish species. As well as the increase of the total catch, the number of commercial fishermen and fishing vessels was also increased in 2003. The number of fishermen who fish for their own consumption (without the right to sell fish–small scale fishermen) in 2004 was 13,700. The total production of fish products in 2004 was 14,270 tons, which is 24.89% less comparing to 2003. Along this decrease, there has been also noticed an increasing trend of the production assortments, specially salted anchovy. The value of import in 2004 was higher than the value of export, although the export/import balance was higher in amount on the import side. Financial subventions payments in 2004 were 67.21% higher comparing to the first year of payments (1997). The highest percentage (32.03%) was paid for the processing of fish in the areas with more difficult commerce conditions.