Local perceptions on the state of the pelagic fisheries and fisheries management in Uvira,Lake Tanganyika,DR Congo

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.     

Managing rivers for fisheries and livelihoods: how can we do it better?

The growing attention being given to improving water productivity at the catchment level has given rise to increased interest in the contribution of aquatic ecosystems and in particular fisheries to reducing rural poverty and improving food security. There is growing recognition that these natural resources have an important role to play in pro-poor water management in many of the world's river basins, but that capacity to optimize these benefits is constrained by a lack of appropriate technologies and tools to do so. The present paper provides an overview of the current state of understanding of these issues and identifies a number of challenges to be addressed, namely the need to: (i) build wider understanding of the value of river fisheries; (ii) understand the water requirements for sustaining river fisheries; and (iii) develop governance arrangements that bring fisheries to the decision-making table. It concludes by distilling from recent reviews of river fisheries valuation, environmental flows, and governance, a set of specific directions that need to be taken in order to meet these challenges.     

Food‐web patterns and diversity in tropical fish communities

The food webs for three Sri Lankan reservoirs, Minneriya (ancient and shallow), Udawalawe (young and shallow) and Victoria (young and deep), were compared. The species richness of the fish communities was highest in Minneriya (30 species), intermediate in Udawalawe (21 species) and lowest in Victoria (18 species). The fish species belonged to 11 families, with Cyprinidae dominating the community in terms of both abundance and species richness. The daily quantity of food consumed per fish species was used to distinguish weak from strong trophic interactions in these food webs. The fish community consumption pattern was characterized by a few strong interactions and many weak ones. The number of major consumers (i.e. contributing >5% of the total fish community consumption) for each reservoir was small and similar for all three reservoirs. Dawkinsia singhala and Amblypharyngodon melettinus were the two major consumers in all three reservoir food webs. Puntius chola was a major consumer in Minneriya and Victoria, although not in Udawalawe, where it fed less on detritus than for the other two food webs. The fish community fed mainly at the bottom of the food web, primarily on algae, macrophytes and detritus in all three reservoirs, with very little piscivory occurring. The average food‐web length was measured as the mean trophic index weighted for the consumption rates of the various fish populations that together comprised the fish community. The average food‐web length in these three Sri Lankan reservoirs relatively short, compared with most other tropical lake/reservoir food webs in Asia and Africa for which relevant data were available. Furthermore, traditionally unexploited species (Oreochromis mossambicus; O. niloticus), in contrast to species of commercial fisheries interest, are major role players in the trophic dynamics of reservoir ecosystems. Thus, based on this study, the potential of their exploitation should be considered in the management of reservoir fisheries.     

Achieving water security in Nepal through unravelling the water-energy-agriculture nexus

ABSTRACT

This article investigates water security in Nepal from the perspective of the water-energy-agriculture (food) nexus, focusing on pathways to water security that originate in actions and policies related to other sectors. It identifies promoting development of Nepal’s hydropower potential to provide energy for pumping as way to improve water security in agriculture. Renewable groundwater reserves of 1.4 billion cubic meters (BCM), from an estimated available balance of 6.9 BCM, could be pumped to irrigate 613,000 ha of rainfed agricultural land in the Terai plains, with a potential direct economic gain of USD 1.1 billion annually and associated benefits including promotion of energy-based industry, food security and local employment. Governance also plays an important role in addressing water security. We conclude that a nexus-based approach is required for effective water management and governance.     

An overview of the current status of Lake Victoria fishery: Opportunities, challenges and management strategies

Lake Victoria is African's most important source of inland fishery production, exhibiting an annual catch of ≈500 000 mt. The lake moderates local climate, serves as a means of transport, and a source of human food and raw material for the fishmeal industry. The introduction of Nile perch transformed the fisheries from a locally based artisanal fishery to a national and international capital investment industry. The fisheries produce an annual income of $US 600 million, providing employment opportunities for over 3 million people. Although the benefits of transforming the fishery of Lake Victoria appear to be quite remarkable, the negative impacts of this development are even more dramatic. Several challenges face the lake fishery, including environmental degradation, the introduction of exotic species, overfishing, and a fish export ban. Nutrients inputs into the lake have resulted in eutrophication and increased algal blooms. Deteriorated water quality and increased anoxia have caused the displacement and decline of some fish species. Exotic tilapiines have hybridized, displacing the indigenous fish species. Nile perch predation has caused the disappearance of once abundant native fish species. The once complex food web is now dominated by Nile perch. Unhygienic fishing methods have led to several fish export bans, while water hyacinth invasion in the lake has affected water quality, fishing and transportation possibilities. The current top‐down management and use of different regulations by the riparian states have been a major drawback to sustainable management of the lake. There is a need for a paradigm shift, in which the lake is considered to be one ecosystem and relevant stakeholders are involved in the decision‐making process.     

Taxonomic status of fish parasites in Kenyan inland water systems and their significance on the freshwater fisheries and aquaculture productivity within the region

Fish are a resource with great economic, nutritional and recreational benefits to humans on a global scale. In Kenya, fish represent an important source of food and income through trade and employment to many communities. In fact, fish are an important alternative source of animal protein, especially in famine‐tolerant arid and semi‐arid regions such as Turkana, Marsabit, Pokot and Baringo Counties, where annual drought periodically hampers traditional livestock keeping destitute. Kenya freshwater fishes have remained vulnerable to a variety of parasites and related diseases. Approximately 119 fish parasites have been reported in the country, with about 83 being identified to species level and 35 to genus level. Out of the reported parasites, 77% were detected in wild fish, 8% in farm fish and 15% in both wild and farmed fish. The parasites identified by various studies include protozoa (7), myxozoa (7), nematode (20), monogenean (33), digenean (16), cestoda (15), acanthocephalan (6) and crustacean (15). The highly commercialized fishes, such as Oreochromis niloticus and Clarias gariepinus, harbour the highest number of parasites, which greatly hinder fisheries and aquaculture productivity through retarded growth, mechanical damages, reduced reproduction rates and increased mortality of the fish hosts. Thus, there is need for adequate information on the taxonomy and ecology of these parasites as a basis for developing appropriate management and policies to control them. This review article is meant to provide an overview of the distribution, occurrence of fish parasites and their impacts on inland water fisheries and aquaculture in Kenya, while also highlighting the available gaps warranting further studies, with the goal of developing appropriate and accurate control measures to improve the region's fisheries and aquaculture productivity and food security.     

How influential is the role of oligotrophication on the integrity of fish assemblages in the littoral zone?

Food web theory predicts that one of the consequences of oligotrophication is the decline in fisheries following the establishment of nutrient-deficient conditions and low biogenic production. However, emerging evidence suggests that more complex trophic interactions, induced by plankton composition, dietary diversification, temporal and spatial heterogeneity, variations in fish age and size structure can lead to ecosystem responses that deviate from theoretical predictions; especially in the shallow littoral zone. In this study, two end-to-end modelling strategies are used to characterize potential food web structural shifts and overall ecosystem productivity in response to oligotrophication. Our modelling strategy draws upon empirical and theoretical evidence from the Bay of Quinte, a semi-enclosed embayment in northeastern Lake Ontario that has been subjected to phosphorus (P) abatement strategies in the 1970s. We first show that the role of food abundance has been a primary factor shaping fish production, but the fish community gradually responded to the reduced availability of pelagic staples of their diet by displaying greater reliance upon alternative sources, including benthic and other autochthonous (or even allochthonous) food items. Our analysis further suggests that degree of diet overlap between competing trophic guilds can significantly modulate realized biomass levels. The composition of the autotrophic community is another major confounding factor that can induce significant variations from the predicted food web productivity patterns in response to oligotrophication. Overall, our analysis suggests that the proposed reduction of the ambient total phosphorus levels may not necessarily trigger a significant decline in fish biomass in the Bay of Quinte.     

Some aspects of reproduction and feeding habits of Nile tilapia (Oreochromis niloticus) in three dams in Uasin Gishu County,Kenya

Knowledge of the fisheries status of dams within Uasin Gishu County was needed prior to the government's plan to introduce fish and fisheries in the area. The dams were constructed in the 1950s and stocked with tilapia for local consumption, recreation and control of macrophytes. The Nile tilapia (Oreochromis niloticus) was selected for the present study due to its establishment success and popularity in the Kenyan market. Water samples were collected at subsurface levels for phytoplankton analysis and compared with the phytoplankton found in the stomachs of O. niloticus, revealing the food preference of the fish in a natural environment. Fish samples were collected with gillnets and beach seines. The results of the present study identified the most important food items for the fish were Chlorophyceae (green algae), Bacillariophyceae (diatoms) and Cyanophyceae (blue‐green algae). The fish exhibited a relative condition factor of about 1.00, indicating their robustness or well‐being in the dams. The LM₅₀was reached at 18–20 cm class interval, which coincides with the most critical breeding biomass needing some kind of protection for sustainable management of the fishery.     

Water security and the pursuit of food,energy, and earth systems resilience

ABSTRACT

This article addresses the emergence and interrelation of food, energy, and water security in terms of resource use and the ensuing societal and environmental outcomes. For decades, food security and energy security have been well-accepted, operational concepts. Water security is the latest entrant, yet the implications of water insecurity for food, energy and earth systems resilience have not been adequately considered. This article examines how and why this is so – particularly with growing water scarcity and insecurity that may compete with energy and food security – and emphasizes the critical need to link water-energy-food nexus approaches to earth systems resilience.     

Selecting indicators to assess the fisheries of Lake Malawi and Lake Malombe: Knowledge base and evaluative capacity

The provision of management information on the fisheries of Lakes Malawi and Malombe has been characterised by top–down controlled single species steady-state assessment techniques originating from single gear industrial fisheries but applied to an open access highly diverse and adaptive small-scale multispecies and multi-gear fishery. The result has largely been an unhappy marriage with uncertainties blamed more on the data than the process, although the data collection generally is detailed and comprehensive on catch and effort parameters. An extensive literature review of primary and grey literature on ecosystem drivers, exploitation pressures, and fish population and community states shows that Malawi has the necessary knowledge base for expanding their assessment into multi-causal and exploratory indicator-based methods that can assist in better understanding and more disciplined use of existing data and monitoring systems. Selection and ranking of a suite of indicators focusing on the major fisheries in the Southeast arm of Lake Malawi and Lake Malombe were done by a group of Malawian fisheries researchers and management advisers, thereby testing a framework of scoring criteria assessing an indicator's acceptability, observability, and relatedness to management. Indicators that are close to raw observational data and that require limited permutations and few assumptions appear to be preferable in the Malawian context. CPUE-based assessments can improve the utility of data and information in communicating developments and processes and evaluate fisheries management policies.     

Difficulties of fishing at Lake Naivasha,Kenya: is community participation in management the solution?

Unlike other lakes in tropical regions, Lake Naivasha exhibits low fish species diversity. The fishery is based on introduced fish species that are not native to the lake. The lake ecosystem is very fragile, as reflected in its fluctuating fish catches. The fishery almost completely collapsed in 2001, due partly to mismanagement and ignorance about needed conservation measures. The Kenyan government, like many governments around the world, recognized the need to involve fishers and other stakeholders, in order to ensure better management of the lake fisheries resources. Also referred to as collaborative management (co-management), this management approach provides the opportunity to share responsibility for managing the fishery resources between the government and the community. A total ban on fishing was imposed in February 2001, lasting for 1 year, to allow lake fish stocks to recover. This study analyses the co-management process for Lake Naivasha, and discusses the role played by the community during the fishing ban, as well as the successes and challenges encountered, and the tribulations and perceptions of the fishers regarding the new management strategy. It also comprises the first documentation of community participation in fisheries management begun for Lake Naivasha in the year 2001.     

When free-riders become the agents for change—migrant fishers,institutional resilience,and adaptive fisheries management in Malawi

Fisheries co-management in Malawi has not achieved the successes anticipated. Mobility of fisherfolk is frequently blamed for the poor effectiveness of local institutions, and this often leads to calls for access limitation. However, recent research in Malawian water bodies suggests that fisher mobility increases livelihood sustainability for all lakeshore residents involved, and is well adapted to these contexts of fluctuating and uncertain fisheries. Therefore, the abilities of fisherfolk to move into and out of different local fisheries can arguably be judged to enhance fisheries resilience overall. In addition to these benefits, we present data from two ethnographic case studies to illustrate the positive impacts that migration has had on some of Malawi's more successful fisheries co-management institutions (known as Beach Village Committees or BVCs).Despite preexisting concerns regarding unsustainable local fishing practices, local stakeholders were unwilling or unable to address these challenges until conflicts with migrant fisherfolk prompted changes. In some cases, the ability of migrants to circumvent BVC regulations has highlighted the BVC's lack of local legitimacy. Additionally, when threatened with losing benefits to “outsiders,” local stakeholders are more willing and able to come together and take corrective action. We therefore argue against policies limiting access to local fisheries as these remove valuable catalysts for adaptive institutional learning in decentralized natural resources management.     

Impacts of Nile Perch,Lates niloticus,introduction on the ecology,economy and conservation of Lake Victoria,East Africa

Nile perch were secretly introduced into Lake Victoria in the 1950s, and officially in the 1960s, amid unresolved controversy. Proponents were of the view that the introduction would improve fisheries production and sport fishing. Although the former objective was achieved, the side effects were dire, including extinction of many native species, especially the ecologically important haplochromines, because of predation. The introduction also changed the habitat, trophic dynamics and water clarity. The change in water clarity is thought to be responsible for hybridization of haplochromines, further contributing to the loss of species diversity among cichlids. The establishment and expansion of the Nile perch also altered the fishery and socio‐economic settings characterizing the lake. A local economy which, until the early 1980s, was based on native fish species has been replaced by an export‐oriented exotic fish processing industry that destroyed the once‐cherished traditional resource. Other socio‐economic issues associated with Nile perch include the high HIV/AIDS prevalence among fishers, and border conflicts attributable to the migratory and transboundary nature of the fishery resource. Conservation measures for the fishery should include establishment of co‐management units that have so far registered both successes and challenges. Other efforts include establishment of the Nile perch Fisheries Management Plans that focus on curbing overfishing and eradicating illegal fishing.     

Burbot Consumption and Relative Abundance in the Apostle Islands Region of Lake Superior

Burbot (Lota lota), are native Lake Superior piscivores that share similar habitat and food resources with other predators including lean and siscowet lake trout (Salvelinus namaycush). To better understand their ecological role in the fish community, we combined fisheries assessment information from 1970 to 2002 with a bioenergetics model to estimate their predatory impact in the Apostle Islands region of Lake Superior. Relative abundance declined in the Apostle Islands region from 3.41 fish/1,000 m in 1978 to 0.27 fish/1,000 m in 1998. Fishing mortality was minimal based on creel estimates and observed bycatch in the commercial fishery. Burbot < 400 mm consumed a higher fraction of small prey items such as Mysis relicta, fish eggs and sculpins (Cottidae) while larger burbot were almost exclusively piscivorous. Overall diet composition (by mass) was represented primarily by Coregonus spp. (64%) and rainbow smelt (Osmerus mordax) (17%). We estimated the burbot population size in the Apostle Islands between 1970 and 2000 at 56,541 to 1,585,035 age 1+ fish. This population consumed between 56 and 1,584 metric tonnes (0.13 to 3.54 kg/ha) of prey. Increases in both lean and siscowet lake trout abundance have likely contributed to the decline in burbot abundance through predation and/or competition for food resources. Given the current burbot population in the Apostle Islands, this species is unlikely to control production of prey fish or invertebrate taxa.     

Summary and conclusions from the SIWI Seminar for Young Water Professionals Drainage basin security--implications of virtual water trade and agricultural subsidies at regional, national and local levels.

This is a summary of the Young Water Professionals Seminar involving more than 50 young people from all over the world working with water. The presentations and following discussion were very lively and were about how subsidies and trade barriers imposed by the developed countries are influencing the income-generating capacity of millions of people in the developing world. Even though this is a very complex issue not easily resolved during the seminar it was also clear that there are some fundamental problems that need to be addressed. The importance of looking for solutions at different levels (i.e. local, regional, national) was highlighted as well as the policy of double standards, preaching free trade but only for the benefit of overdeveloped countries themselves. Further it was discussed how to achieve basin security through food security, and managing water for food security. The conclusion was that win-win solutions would be made if agricultural subsidies were to be completely removed.     

Water Security Assessment: Integrating Governance and Freshwater Indicators

A new approach is developed for assessing water security status: the Water Security Status Indicators (WSSI) assessment method. The WSSI has four innovative aspects which address important gaps in the literature. First, it was developed in cooperation with end-users, whose participation enabled the design of a user-friendly assessment method. Second, this method is designed to be implemented at the local scale (small scale watershed or sub-watershed). Third, the WSSI is multivariate: it integrates variables pertaining to water quality and water quantity as they relate to aquatic ecosystems and human health. Fourth, the method provides concrete outputs for incorporation into water decision-making processes. In this paper, we document the WSSI assessment method and its application in a community in British Columbia (Canada), including the incorporation of community input into the development and application of the WSSI, and the integration of WSSI results into community water governance.     

The Lake Michigan Charter Fishing Industry: a Product of Love and Taxes

Little is known about the Lake Michigan charter fishing industry. This study was conducted to describe Lake Michigan charter fishing boat operators and their customers and to evaluate the industry's financial status and local economic impact. Field work in 1973 revealed 98 charter operators working on Lake Michigan from Wisconsin ports. From a geographically proportionate sample, 44 extensive interviews were completed. The industry generated $670,000 in sales in 1973. Low average sales and profits do not provide financial incentives to entrepreneurs. Financial opportunity, however, appears to have played a minor role in the decision to enter business. Major motivations appear to be tax advantages and life style rewards. A profile of charter customers was developed through a mail survey of a sample of 483 charter customers. Catch data were collected from operators surveyed. Catch varied with the proportion of operator income obtained from charter fishing, Port communities were affected economically by the industry. Applying a community multiplier of 2.16 to the $1.6 million of direct expenditures yields an economic impact of $3,456,000 on Wisconsin's Lake Michigan community in 1973. The industry is also important in that it provided fishermen with access to the Great Lakes lake trout and salmon fisheries. Without that access, these fisheries would be largely reserved for the wealthy.     

Tonle Sap Lake,Cambodia: A perspective on its transborder hydrological and resources governance

Tonle Sap Lake is the largest freshwater lake in South East Asia, being situated at the heart of the Mekong River Basin. Governance of the lake over the recent past has been weak and overly complex, and the basin governance structure has changed over time in terms of its fisheries management framework. The governance framework initially focused on the commercial exploitation of fish resources, but has more recently switched to a community‐based fisheries management, biodiversity conservation and open access model. This study discusses how the water flows occurring between the Mekong River and Tonle Sap Lake complicate the governance of the lake, and particularly its fisheries, biodiversity, land and water management activities. The establishment of the Tonle Sap Authority (TSA) in 2007 sought to address the governance challenges facing the lake. The current study concludes, however, that the TSA alone is not sufficient and that global, regional and national stakeholders must make an effort to ensure the water flows between the lake and the Mekong River are themselves considered a core governance issue for the Tonle Sap.     

Identifying Water Security Issues at the Local Level

Abstract

Water security has been traditionally thought to be an issue for developing countries. In the United States, the Clean Water Act has made water quality and watershed management increasingly relevant to community decision makers. However, the extent to which local stakeholders perceive and understand water scarcity and quality constraints in the United States remains uncertain. The reported research uses a series of focus groups to evaluate their efficacy and for learning from local beneficiaries about local water security concerns for mid-Michigan's Red Cedar River. In Michigan, it appears that the water security issue is water quality. The findings show that focus groups are effective data collection tools and that Michigan stakeholders recognize water security problems, causes, and potential solutions.     

西南地区河流灌溉发展规划研究

西南地区河流一般地跨多个不同的气候带,差异大且各具特色,灌溉规划不仅要在总体上统筹区域粮食安全、农民增收和生态安全问题,还要因地制宜,突出重点。所研究的流域在西南地区具有较强的代表性,分析了其灌溉发展现状与发展需求,探讨了既符合现代流域综合规划要求,又契合西南地区实际情况的流域灌溉发展模式。灌溉发展规划实施后,该地区农田水利建设的状况将得到改善,水资源供需矛盾也将得到缓解,而且,粮食安全将得到保障。