Fisheries Management and Ecology最新文献

{"title":"Modeling food web and fisheries dynamics in Lake Baringo, Kenya","authors":"J. Walumona, B. Kaunda-Arara, Cyprian Ogombe Odoli, Pascal Masilya Mulungula, Raburu Philip, B. Kondowe, N. Kobingi, Mugo James Murakaru, Mbalassa Mulongaibalu, Fabrice Amisi Muvundja","doi":"10.1111/fme.12725","DOIUrl":"https://doi.org/10.1111/fme.12725","url":null,"abstract":"Lakes are important in supporting ecosystem services and livelihoods. However, their food webs and ecological functioning are continuously threatened by anthropogenic influences. Food web models have been widely used in studying trophodynamics, fisheries impacts, and ecological functioning of temperate lakes, but less often in Afrotropical lake systems. We used Ecopath mass‐balanced trophic models annually in 1999, 2010, and 2020 to assess trends in ecosystem function, and the impact of fisheries on the Lake Baringo Ecosystem, a shallow freshwater lake in Kenya. Pre‐balance (PREBAL) and Pedigree analyses supplemented Ecopath models. Model input data were from field sampling, published and gray literature. Food web trophic models indicated a bottom‐up grazer and detrital food chains in all 3 years. Odum's ecosystem development indicators (total productivity to total biomass and total respiration ratios; TPP/TB and TPP/TR) showed that the lake was in a low to intermediate developmental stage, with room for bio‐manipulation, and a highly reduced mean transfer efficiency (TE) (6.4%–0.49%) indicated low trophic transfer of internal production. System omnivory (SOI) and connectance (CI) indices that varied among years indicated temporal variation in food web complexity. Indices of system resilience (overhead and ascendency) indicated an increasing potential for the lake to recover from perturbations. The mean trophic level of the catch (MTLc) increased from 1999 to 2010 and decreased in 2020, by fishing down the food chain as fishing pressure increased. Oreochromis niloticus, an endemic cichlid, was the keystone species (KSi >0) controlling community structure, while the lungfish Protopterus aethiopicus, the top predator in the lake, was not a keystone species (KSi <0). We recommend an integrated approach to lake management that incorporates watershed regulations, regulates fishing effort on the keystone species (O. niloticus), and monitors water quality for sustainable management of the Lake Baringo ecosystem.","PeriodicalId":50444,"journal":{"name":"Fisheries Management and Ecology","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141650479","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ecosystem responses to a whole‐reservoir coarse woody habitat addition","authors":"C. C. Fenstermacher, D. S. Radford, A. P. Porreca, G. G. Sass, J. J. Parkos","doi":"10.1111/fme.12728","DOIUrl":"https://doi.org/10.1111/fme.12728","url":null,"abstract":"The addition of coarse woody habitat (CWH) is often used to mitigate the loss of natural structure in aging waterbodies. Ecosystem‐scale effects of large‐scale CWH additions and their influence on fish productivity have been assessed in oligotrophic, natural lakes, but need to be assessed in more ecosystems. Therefore, we tested the effects of an ecosystem‐scale addition of CWH to a eutrophic reservoir using a reference reservoir and data from 4 years before and 4 years after habitat enhancement. Zooplankton and benthic macroinvertebrates did not respond to the addition of CWH, but bluegill (<jats:italic>Lepomis macrochirus</jats:italic>) reproductive productivity and largemouth bass (<jats:italic>Micropterus salmoides</jats:italic>) size structure increased. Positive fish responses that contrasted with a lack of fish population‐level responses after a similar CWH addition in an oligotrophic, natural lake highlight the importance of assessing the efficacy of CWH addition across diverse ecosystems.","PeriodicalId":50444,"journal":{"name":"Fisheries Management and Ecology","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141610492","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Size-based indicators of unexploited deep-sea community in the Colombian Caribbean Sea","authors":"Jorge Paramo,&nbsp;Daniel Pérez","doi":"10.1111/fme.12720","DOIUrl":"10.1111/fme.12720","url":null,"abstract":"<p>Composition, size distribution, structure, and function of deep-sea marine communities must be understood before they are impacted by anthropogenic effects. The deep-sea ecosystem of the Colombian Caribbean Sea is unexploited with no fishing activity ever registered. We quantified the current state of the marine community using body size distribution (size-spectra), size-based indicators, minimum length (L_MIN), maximum length (L_MAX), average length (L_mean), standard deviation of length (L_SD), 10th and 90th percentiles of the length distribution, Shannon–Wiener diversity (<i>H</i>′), and Pielou's evenness (<i>J</i>′) to generate a baseline of potential ecological indicators that contribute to management and conservation of the Colombian bento-demersal community of deep-sea marine ecosystem. Sampling was in the Colombian Caribbean Sea at 58 stations during four samplings in August and December 2009, 21 stations in March and May 2010, and 45 stations from August to December 2020, using the swept area method, at depths of 200–550 m. Catches included &gt;50% families and species of fish, followed by 27 families (30%) and 33 and species (37%) of crustaceans. Chondrichthyes included 14% families and 9–11% species. Cephalopods included 2–3% families and 1–4% species. Size-spectra analysis confirmed expected values for unexploited communities in three sampling years for teleostei, crustacea, and whole community.</p>","PeriodicalId":50444,"journal":{"name":"Fisheries Management and Ecology","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141575899","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of stocking on brown trout angling catch rates in the Czech Republic during 1996–2018","authors":"Luděk Šlapanský, Michal Janáč, Pavel Jurajda","doi":"10.1111/fme.12726","DOIUrl":"https://doi.org/10.1111/fme.12726","url":null,"abstract":"When investigating potential causes of apparent declines in European brown trout angling catch rates over recent decades, fisheries management procedures are rarely considered. Using a 20‐year dataset of brown trout stocking and angling catch rates, we found a significant decline in brown trout angling catch rates in streams of East Bohemia, Czechia, were well predicted by a reduction in the number of brown trout stocked at catchable size (i.e. age‐3+). Increased stocking of smaller sized brown trout, and recent sporadic efforts to stock large brown trout, had no effect on catch rates. Our findings suggest that brown trout catch rates were related to ‘put‐and‐take’ stocking, in which non‐native rainbow trout gradually replaced brown trout in both stocking and catches. Our study stresses the importance of considering historical fisheries management, a sometimes‐neglected factor, when studying angling catches of economically important species.","PeriodicalId":50444,"journal":{"name":"Fisheries Management and Ecology","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141547163","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Collaborative research enhances selectivity in a lake fishery","authors":"Alfred Sandström, Johnny Norrgård, Thomas Axenrot, Henrik Ragnarsson‐Stabo, Malin Setzer, Tomas Jonsson","doi":"10.1111/fme.12723","DOIUrl":"https://doi.org/10.1111/fme.12723","url":null,"abstract":"Size and species selectivity are crucial for developing sustainable fisheries. Our objective was to estimate the selectivity of whitefish fisheries in a large European lake through a collaboration of fishers, regional managers, and scientists. Fishers were given special permits to test, within a common framework and together with scientists, selectivity enhancement strategies adapted to their own experiences. Fishers and scientists jointly tested gillnets and pontoon traps and how fishing depth, soak time, fishing season, and mesh size were affected by bycatches of undersized fish of sensitive species. Results indicated that the selectivity of the fishery could be increased, particularly by targeting whitefish adjacent to spawning sites where spatiotemporal overlap with bycatch species was lower. Proposed changes to the fishery, such as new gear, would be costly initially but could become profitable over time due to a lower cost of handling bycatch. Our findings demonstrated that co‐constructed knowledge can contribute to the governance of aquatic resources.","PeriodicalId":50444,"journal":{"name":"Fisheries Management and Ecology","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141547195","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Interacting effects of density and temperature on growth of wild and hatchery young‐of‐the‐year anadromous brown trout (Salmo trutta L.)","authors":"Adam M. Lejk, Szymon Smoliński, Maksym Łaszewski, Grzegorz Radtke","doi":"10.1111/fme.12724","DOIUrl":"https://doi.org/10.1111/fme.12724","url":null,"abstract":"Stocking can affect population density but may influence fish growth responses to changes in environmental conditions. In a multi‐year field experiment, we investigated the interactive effects of density and temperature on the growth of young‐of‐the‐year anadromous brown trout in streams stocked with wild‐origin hatchery‐reared brown trout. Fish origin was the predominant factor influencing growth rate, thereby highlighting the importance of discriminating between wild and hatchery‐reared individuals. Growth was positively related to temperature (degree‐days) and negatively related to density, with the growth response to temperature modulated by density. Temperature had a more pronounced effect on juvenile growth at low density than at high density. The reduced growth response to temperature caused by density could reduce population resilience and should be considered in management and conservation strategies.","PeriodicalId":50444,"journal":{"name":"Fisheries Management and Ecology","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141547166","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sensitivity of the stock assessment for the Antarctic krill fishery to time‐varying natural and fishing mortality","authors":"Elling Deehr Johannessen, Bjørn A. Krafft, Carl R. Donovan, Rodrigo Wiff, Bruno Caneco, Andrew Lowther","doi":"10.1111/fme.12721","DOIUrl":"https://doi.org/10.1111/fme.12721","url":null,"abstract":"The stock assessment model for the Antarctic krill fishery is a population model operating on daily timesteps, which permits modeling within‐year patterns of some population dynamics. We explored the effects of including within‐year patterns in natural and fishing mortality on catch limits of krill, by incorporating temporal presence of key predator species and contemporary temporal trends of the fishing fleet. We found that inclusion of within‐year variation in natural and fishing mortalities increased catch limits. Fishing mortality had a greater effect than natural mortality despite differences in top‐down predation on krill, and potentially increased catch limits by 24% compared to the baseline model. Additionally, the stock assessment model allowed a higher catch limit when fishing was during peak summer months than autumn. Number of days with active fishing was negatively related to precautionary catch limits. Future stock assessments should incorporate contemporary spatiotemporal fishing trends and consider implementing additional ecosystem components into the model.","PeriodicalId":50444,"journal":{"name":"Fisheries Management and Ecology","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141501761","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Unveiling interconnectedness between marine protected and non‐protected areas in Tanzania: Insights from barred mudskipper (Periophthalmus argentilineatus) population genetic structure","authors":"Cyrus Rumisha","doi":"10.1111/fme.12722","DOIUrl":"https://doi.org/10.1111/fme.12722","url":null,"abstract":"Marine protected areas (MPAs) are globally recognised for their role in safeguarding marine fisheries from the detrimental impacts of human activities and climate change. Tanzania, in alignment with global conservation efforts, has designated 18 MPAs and plans to establish four more in the Southwestern Indian Ocean. However, a critical challenge arises from the lack of a thorough understanding of genetic connectivity between populations in MPAs and non‐protected areas (NPAs). To address this, 151 mitochondrial D‐loop sequences (357 base pairs) of Barred mudskipper (<jats:italic>Periophthalmus argentilineatus</jats:italic>) were analysed to assess genetic connectivity between MPAs and NPAs in Tanzania. The findings revealed a low and insignificant index of genetic differentiation (<jats:italic>F</jats:italic><jats:sub>ST</jats:sub> = −0.0046, <jats:italic>p</jats:italic> &gt; 0.05) between populations in MPAs and NPAs. Furthermore, haplotypes from both MPAs and NPAs did not cluster based on their geographical origins, with over 9 haplotypes shared between these areas. Additionally, the measured haplotype and nucleotide diversities did not differ significantly between MPAs and NPAs (<jats:italic>p</jats:italic> &gt; 0.05). However, MPAs showed a significantly higher number of private haplotypes compared to NPAs (<jats:italic>p</jats:italic> &lt; 0.05). These findings suggest high genetic interconnectedness between populations in MPAs and NPAs, underlining the importance of existing MPAs in preserving local genetic diversity and their potential to replenish depleted NPAs. However, realising the full potential of this interconnectedness necessitates stringent enforcement of sustainable fishing practices to alleviate pressure on fish stocks. It also requires the protection of critical habitats that serve as corridors for fish dispersal, facilitating interconnectedness between MPAs and NPAs.","PeriodicalId":50444,"journal":{"name":"Fisheries Management and Ecology","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141501762","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Willingness to pay for recreational fisheries in Europe","authors":"Ing-Marie Gren,&nbsp;George Marbuah","doi":"10.1111/fme.12719","DOIUrl":"10.1111/fme.12719","url":null,"abstract":"<p>Few studies have acknowledged and quantified the economic contribution in expenditures of recreational fisheries. Additional economic value attributed to fishers' willingness to pay (WTP) for recreational fisheries in excess of expenses was estimated for 33 countries in Europe. Benefit transfer was used in a meta-regression analysis of 184 studies and 1001 observations of WTP per day for recreational fisheries. Most studies of fishing were in the USA, but also in Europe, Australia, New Zealand, South America and Canada. Mixed-effects regression models were estimated with income, climate variables, population density and study characteristics as explanatory variables. Income and temperature positively affected WTP per day. Benefit transfers with these variables and different transfer methods among European countries showed that the estimated total WTP could amount to 11.4 billion USD (purchasing power parity corrected to 2020 prices). Variation in WTP per day was large, and ranged 9–62 USD among countries and transfer methods. For several countries, WTP for recreational fisheries exceeded 0.1% of gross domestic product.</p>","PeriodicalId":50444,"journal":{"name":"Fisheries Management and Ecology","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/fme.12719","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141341264","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Value of data in stock assessment models with misspecified initial abundance and fishery selectivity","authors":"Miren Altuna-Etxabe,&nbsp;Dorleta Garcia,&nbsp;Leire Ibaibarriaga,&nbsp;Quang C. Huynh,&nbsp;Hilario Murua,&nbsp;Thomas R. Carruthers","doi":"10.1111/fme.12718","DOIUrl":"10.1111/fme.12718","url":null,"abstract":"<p>The age-structured assessment model available in the MSEtool R package assesses stock status and exploitation for varying data availability, from limited to rich datasets. We investigated model accuracy in relation to data availability, population exploitation levels, initial population assumption and fishery selectivity misspecification. Estimates were accurate in all conditions when data were available for a stock in an unfished state. However, for estimates to be accurate without complete exploitation data, total catch and abundance index data needed to span more than two stock generations. When the data time series was shorter than two generations, fishery mean lengths spanning one generation improved relative estimates (e.g. depletion), but precise estimates of unfished recruitment required fishery age- or length-structured data.</p>","PeriodicalId":50444,"journal":{"name":"Fisheries Management and Ecology","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141196643","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}