Aquatic Ecosystem Health and Management最新文献

{"title":"Sex reversal dynamics of Nile Tilapia (Oreochromis niloticus) and impact on growth performance","authors":"Grace Nduku, D. Mirera, Jared Nyabeta","doi":"10.14321/aehm.025.04.68","DOIUrl":"https://doi.org/10.14321/aehm.025.04.68","url":null,"abstract":"Nile Tilapia (Oreochromis niloticus) is one of the most economically important freshwater aquaculture species globally. However, reproduction during grow-out is a major problem that hinders fish growth. Therefore, production of all-male populations of tilapia has been developed to address the problem and is also identified as one of the most effective techniques of increasing tilapia growth. Various methods have been used to produce all males in Nile Tilapia i.e. use of hormone treatment (17- α-methyltestosterone), use of temperature shock and the recent YY technology. The latter two methods have limited documentation and usage in Kenya. The current study compared effectiveness of temperature and hormone sex reversed O. niloticus fry and influence on growth in hapa nets over a period of 3 months. Nile Tilapia fry of 3 days old after egg yolk absorption were sex reversed using hormone for 21 days and temperature shock for a period of 14 days. Hormone use involved making a dose of 60 mg kg-1 of feed while temperature shock involved raising temperature from 28°C to between 30 °C and 34 °C. Analysis of Specific Growth Rate using one-way analysis of variance, ANOVA, showed no significant difference between hormone and temperature induced sex reversed fish (F=0.0975, P=0.7705). Sex reversal efficacy rates of 91.18% and 92.86% were attained using 17- α-methyltestosterone hormone and temperature shock, respectively. The results indicate that temperature shock could be a replacement for Tilapia sex reversal without any negative consequences on growth.","PeriodicalId":421207,"journal":{"name":"Aquatic Ecosystem Health and Management","volume":"77 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124964442","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Market efficiency as indicators of fish market along the middle stretch of River Ganga, India","authors":"Jahanara Shaikh, R. Shrivastava, Dharmnath Jha, Amit Ranjan Pandey","doi":"10.14321/aehm.025.03.55","DOIUrl":"https://doi.org/10.14321/aehm.025.03.55","url":null,"abstract":"The fish market in the state of Uttar Pradesh, India, is not formally organised. Rather, it permeates from a direct fisher market to a wholesale market. Fish caught from the River Ganga are distributed through many intermediaries and are transported to farther regions like Guwahati and Kolkata in the east. The objective of the study is to assess market efficiency and, with this assessment, make recommendations that can be used to improve the livelihoods of the fishers. We accomplish this by investigating market efficiency indicators including production capacity of the area, Percent Share of Fisher in the Consumer's Money, and price stability of fish markets in different districts (including Bulandshahr, Farrukhabad, Kanpur, Fatehpur, Prayagraj and Varanasi). These are the districts that are located on the bank of the River Ganga in the state of Uttar Pradesh. The study consists of interviews with fishers, wholesalers, vendors, auctioneers, and consumers. The study examines 9 wholesalers, 9 retail markets and 1 direct fisher market. The demographic variables of fish sellers viz. age, education, caste, family size, experience and occupation are also studied. Descriptive statistics and cross-tabulation are used for nominal variables to measure and test conceptions and misconceptions of the fish market. Fish selling is carried out through fish market channels including 220 middlemen, 249 retailers, 48 wholesalers, and 72 auctioneers. Together, these individuals make up the channel structure, channel strategy, and channel performance. The high number of middlemen demonstrates that the market structure is inefficient. Higher Percent Share of Fisher in the Consumer's Money was observed for fishes like Labeo rohita (65.8%), Cirrhinus Mrigala (64%), and Labeo Calbasu (64.3%). The average Percent Share of Fisher in the Consumer's Money is 54% and shows the fishers earn little more than half of the revenue generated. The study shows that high-value fish have less price stability and low-value fish have high price stability across the fish market channel, respectively. Our investigation recommends reducing the number of market channels with the application of modern infrastructure in order to increase the quality of products received by the consumer and to increase fisher share in consumer's money.","PeriodicalId":421207,"journal":{"name":"Aquatic Ecosystem Health and Management","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123845307","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ecosystem service trade-offs at small lakes: Preferences of the public and anglers","authors":"J. Meyerhoff, T. Klefoth, R. Arlinghaus","doi":"10.14321/aehm.025.03.01","DOIUrl":"https://doi.org/10.14321/aehm.025.03.01","url":null,"abstract":"Small lakes provide substantial ecosystem services to society, particularly recreational services. These ecosystem services are rarely quantified. It is also unclear whether expectations about desired lake attributes by various user groups and the public at large align. In many landscapes most small lakes artificially originate from sand and gravel mining along highways and close to cities. Using a choice experiment, in samples from north-western Germany we quantified the ecological services provided by these so-called gravel pit lakes and investigated potential conflicts among the preferences of the public and anglers as a specific user group. The same visual choice sets were employed to assess the preferences for different recreational services as well as biodiversity attributes. We also tested whether the presence of anglers at the small gravel pit lakes affected how people from the public valued the services provided by the lakes. Both the public and the anglers valued the presence of endangered fish species and endangered other taxa positively, suggesting that improved conservation of biodiversity would benefit all users. The public and anglers varied in relation to the recreational uses desired at gravel pit lakes. The opportunity to swim was valued positively by the public and negatively by the surveyed anglers. Yet, the presence of anglers did not significantly reduce the value assigned to gravel pit lakes by the public, suggesting the co-existence of anglers and swimmers would be possible. Co-existence could be fostered through establishing separate angling and swimming zones. Our work suggests the presence of local trade-offs in the management of small gravel pit lakes, specifically between swimmers and anglers. However, conservation of endangered species constitutes a common goal that suits the expectations of all.","PeriodicalId":421207,"journal":{"name":"Aquatic Ecosystem Health and Management","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131560164","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Socioeconomic study of traditional fish farmers and trained farmers in the Indian Sundarbans ecosystem","authors":"S. Ghosh, A. Baidya, B. Ghosh, N. Sahu, F. Rahaman, A. Das, K. Das","doi":"10.14321/aehm.025.03.63","DOIUrl":"https://doi.org/10.14321/aehm.025.03.63","url":null,"abstract":"The Sundarbans, major marshy land, and brackish water ecosystem of the West Bengal were inhabited by many species of fishes which were the main dependants of the people living there. The present investigation was conducted using a questionnaire survey, participatory rural appraisal, key informant interviews, and focus group discussion and to assess the present state of production of major cultivable species of Sundarbans like mullet, shrimp, tilapia, mud-crabs, giant prawn and Asian seabass. A socioeconomic and technical survey of 45 trained and 45 traditional practitioners of aquaculture were conducted from May 2017 – April 2018. This study and appraisal intended to compare the socioeconomic relationship between traditional fish farmers and trained aquaculturists in Indian Sundarbans. The modern farmers usually practice the farming systems like Jayantirohu cultivation, white shrimp cultivation, genetically improved farmed tilapia, crabs fattening and crab culture; periphyton based giant prawn cultivation and Asian seabass culture with forage feeding with bait fishes. The trained farmers were enriched with much knowledge and information gained from various training, which the traditional farmers were lacking. It was found average benefit-cost ratio for traditional farming and modern farming system of 1:1.89 for traditional fish farmers and 1:3.13 for trained farmers. It was helping the modern practitioners to earn more profit to suffice their family needs as well as they were now accomplishing more safety, security measures for their family, investing more in their aquaculture practices. The yield of fish culture was affected by pond conditions, family labor engagement, and resource endowment of the fisher family. Linkage with formal financial institutions, subsidized input support from the fishery department, and investment in human resource development of farmers might be some point of intervention to boost fish culture in the coastal zone of West Bengal, India.","PeriodicalId":421207,"journal":{"name":"Aquatic Ecosystem Health and Management","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131296825","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sociocultural ecosystem services of small-scale fisheries: challenges, insights and perspectives for marine resource management and planning","authors":"M. Stithou, M. Kourantidou, V. Vassilopoulou","doi":"10.14321/aehm.025.03.22","DOIUrl":"https://doi.org/10.14321/aehm.025.03.22","url":null,"abstract":"Sociocultural ecosystem services of fisheries, ranging from social cohesion to sense of place, render their contribution to social wellbeing particularly significant especially at local and regional levels. However, this contribution has not received adequate attention among policy-makers since marine management focuses primarily on provisioning services, and conventional economic indicators used to track performance and inform management, do not allow integration of sociocultural parameters. In our analysis, we draw lessons from small-scale fisheries and discuss in more detail attempts and methodologies to capture such aspects and identify avenues through which they can feed into marine management with an emphasis on spatial planning. The inherent difficulty in capturing sociocultural dimensions along with limited efforts to do so thus far, add to a missed opportunity to improve management and advance spatial planning efforts. In this context, we explore the importance of sociocultural ecosystem services in small-scale fisheries along with attempts and methods to capture and incorporate them into management and planning with a focus in the Mediterranean. We argue that sociocultural ecosystem services of small-scale fisheries constitute an essential element of sustainable development and key factor of enhancing the resilience of coastal communities.","PeriodicalId":421207,"journal":{"name":"Aquatic Ecosystem Health and Management","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132729763","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nutrient composition and microbial food safety of a locally-processed fish product in Cambodia","authors":"Qijin Wang, K. Byrd, Chea Navin, S. Thilsted, V. Try, Miratori Kim, M. Lejeune, R. Worobo, S. Than, K. Fiorella","doi":"10.14321/aehm.025.03.73","DOIUrl":"https://doi.org/10.14321/aehm.025.03.73","url":null,"abstract":"Prahoc is a traditional, fermented fish product in Cambodian diets. Fermented products like Prahoc may play a range of beneficial roles nutritionally, culturally, and financially. However, the use of freshwater fish and long-term storage may also pose food safety risks of parasites and microorganisms. We conducted a mixed-methods study of Prahoc to describe the complex risks and benefits of this food that included semi-structured interviews (prahoc-producing households, n=22; small and medium enterprises n=6), production observation, sample collection and analysis of nutrient composition and food safety parameters. Nutrient composition analysis showed that while Prahoc contributes small amounts of zinc, iron, and other key minerals to the diet, it is also very high in sodium (∼101,621 mg kg-1). Food safety analyses showed that while further tests are needed to resolve Listeria monocytogenes, Salmonella spp., and Vibrio risks, all samples were in compliance with the Cambodia Standards for Prahoc, and there was no evidence of parasites. Participants described Prahoc as playing an essential dietary and cultural role, and also making important contributions to household welfare, particularly within households and businesses that sold Prahoc. Despite the potential risks of microbial food safety and high sodium intake, Prahoc production offers benefits by adding value to fresh fish, reducing loss and waste, and preserving the harvest. However, Prahoc production depends on fish availability and is limited by declining access and high prices. Thus, freshwater fisheries management should take into account Prahoc production activities, an important value chain activity that contributes to the livelihoods of rural Cambodian communities.","PeriodicalId":421207,"journal":{"name":"Aquatic Ecosystem Health and Management","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128493172","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Inland fisheries and the four pillars of food security in Sub-Saharan Africa: Assessing current research trends","authors":"Edith Gondwe, Abigail Bennett, Park Muhonda, E. Rice","doi":"10.14321/aehm.025.03.42","DOIUrl":"https://doi.org/10.14321/aehm.025.03.42","url":null,"abstract":"Inland small-scale fisheries provide important ecosystem services in sub-Saharan Africa as a source of nutritious food to over 200 million people and offer avenues for countries to attain Sustainable Development Goal 2. However, there is a dearth of knowledge on the pathways of fish to food security, especially in the case of inland small-scale fisheries, which are often underrepresented in research and policy discussions. We review the literature from 2010 to the present to assess how fish food systems, specifically those associated with inland small-scale fisheries in sub-Saharan Africa, relate to the four pillars of food security: availability, access, utilization, and stability, as well as women's empowerment. We offer an assessment of the extent to which each of these pillars of food security has been thoroughly conceptualized and investigated in the literature, identifying important avenues for future research. Overfishing, post-harvest losses, and trade influences drive fish availability in many contexts. Income benefits from participating in small-scale fisheries were important for attaining access to fish for food security and other important livelihood outcomes. Few studies addressed utilization and stability compared to availability and access pillars. Further, few studies examined how gender shapes outcomes of women's empowerment. The results lead to the proposed research agenda of focusing on all pillars of food security that can enhance the sustainable contribution of inland small-scale fisheries to food security.","PeriodicalId":421207,"journal":{"name":"Aquatic Ecosystem Health and Management","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130686721","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Perceived socio-cultural ecosystem services provided by wild Atlantic Salmon populations in four European countries","authors":"Sophia Kochalski, Carsten Riepe, R. Arlinghaus","doi":"10.14321/aehm.025.03.12","DOIUrl":"https://doi.org/10.14321/aehm.025.03.12","url":null,"abstract":"Atlantic Salmon (Salmo salar) has always been a highly valued migratory fish species in central and northern Europe. Wild populations have declined since the late 19th century, including local extinctions. We conducted an online survey in France, Germany, Sweden and Norway (N = 2 298) to examine the perception of the general public of the socio-cultural ecosystem services provided by this threatened species. Eleven ecosystem services and benefits were operationalized in the form of 13 survey items and grouped by an exploratory factor analysis into three groups: intrinsic-ecological, extractive and aesthetic-educational ecosystem services. Our analysis showed that the general population perceived a wide range of ecosystem services. Intrinsic-ecological and aesthetic-educational ecosystem services were well recognized in all countries. The values of these two categories were determined most strongly by country and respondents' personal values and perception of Atlantic Salmon, e.g. as threatened and belonging to a healthy river. The high level of approval for aesthetic-educational ecosystem services confirmed that Atlantic Salmon can serve as a charismatic flagship species. Extractive ecosystem services received lower ratings than intrinsic-ecological and aesthetic-educational ones, particularly in Germany where no natural populations remain. In Norway, the country with the highest proportion of healthy stocks and a close cultural connection to Atlantic Salmon, all ecosystem service categories were rated significantly higher than in the other three countries. Synergies between the ecosystem services of Atlantic Salmon explain these results: with healthy stocks and their extractive use, the cultural connection is also strengthened, and this contributes to a greater appreciation of Atlantic Salmon for intrinsic-ecological and aesthetic-cultural reasons. Our study underscores how the ecosystem services of Atlantic Salmon perceived by society are co-produced by the ecological state and continued experience of the species by the wider public. Improving the ecological status and increasing public awareness can therefore foster the development of perceived ecosystem services and the value of a species in the public eye.","PeriodicalId":421207,"journal":{"name":"Aquatic Ecosystem Health and Management","volume":"59 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124131422","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of Mekong River biodiversity on the food culture of women and children in Prey Veng, Cambodia","authors":"Mulia Nurhasan, Daream Sok, S. Thilsted, Samnang Nguon, David James, Christian Ritz, S. Sok, Chamnan Chhoun, N. Roos","doi":"10.14321/aehm.025.03.82","DOIUrl":"https://doi.org/10.14321/aehm.025.03.82","url":null,"abstract":"Situated in the heart of the Mekong River basin, the biodiversity of Cambodian freshwaters is high, with around 475 fish species. Fisheries have shaped Cambodian culture, including traditional diets. Fish and other aquatic animals are the main and culturally preferred animal-source foods in a population vulnerable to food insecurity and malnutrition. The food culture of consuming fish with the bones and head is nutritionally valuable, providing high-quality nutrients. The objective of this study was to assess the consumption of fish and other aquatic animals among mothers and their young children, with details on species, types of processing, and parts consumed. We interviewed 100 mothers in Prey Veng Province, Cambodia, on fish and other aquatic animals consumed by themselves and their children (one child per mother) during the preceding rainy season. To support recall of fish consumption, we used 157 cards with pictures of fish and other aquatic animal species and 11 cards with processed fish. Our results showed that species diversity in mothers' diets was higher than that of their children; on average, mothers and children consumed 69 and 14 species of fish, eight and one species of other aquatic animals, respectively, in the preceding rainy season. On average, mothers reported they knew of 113 fish species and 14 other species available in their surrounding environments. Consuming fish with the head and bones is common among mothers but not children. Our study showed that the rich biodiversity of aquatic animals in the Mekong River is reflected in the food culture of mothers, but not in children. Consequently, children in their most critical period, do not harness the nutritional benefits from the rich aquatic biodiversity. We suggest policymakers recommend feeding young children with a larger diversity of aquatic animals and promoting fish processing to allow young children to benefit from the rich aquatic diversity and their nutrient-rich parts.","PeriodicalId":421207,"journal":{"name":"Aquatic Ecosystem Health and Management","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114402115","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The impact of culture on market competitiveness and food security for small indigenous species: An examination of the Dagaa fishery in Lake Victoria, Kenya","authors":"H. O. Onyango, J. Ochiewo","doi":"10.14321/aehm.025.03.34","DOIUrl":"https://doi.org/10.14321/aehm.025.03.34","url":null,"abstract":"The Dagaa fishery accounts for the largest production in Lake Victoria, with many socio-economic benefits to artisanal fishers, traders, and most riparian poor households. However, it has lagged in comparative value to other key endemic species because it is perceived as fish for the poor. This study sought to investigate the influence of Luo socio-cultural perception of Dagaa on the purchasing habits of local Kenyan households. Secondary data from the 2015/16 Kenya Integrated Household Budget Survey was used to conduct a multiple linear regression to test the research hypothesis. Results indicate that being a Luo household in the Lake's basin could reduce consumption of Dagaa by an estimated 0.055 kg per week, whereas a food-poor household is apt to consume 0.062 kg more Dagaa within the basin. We therefore recommend that culture should be considered and mainstreamed in developing technologies and marketing strategies for the Dagaa fishery of Lake Victoria.","PeriodicalId":421207,"journal":{"name":"Aquatic Ecosystem Health and Management","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131557949","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}