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Fishing for sustainability: Towards transformation of seagrass-associated small-scale fisheries
Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
2017 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Small-scale fisheries employ many millions of people around the world, and are particularly important in developing countries, where the dependency on marine resources is high and livelihood diversification options are scarce. In many areas of the world however, small-scale fisheries are at risk which threatens the food security and wellbeing of coastal people. Small-scale fisheries management has in many cases been insufficient and new comprehensive approaches are recommended to achieve social-ecological sustainability in the long-term. The aim of this thesis is to analyze empirically how social-ecological elements of seagrass-associated small-scale fisheries in the Western Indian Ocean region can be addressed for a transformation from the current mostly degraded state to more sustainable social-ecological systems and secure future livelihoods. The main method used was semi-structured interviews with local fishers. The main findings show the crucial contributions seagrass-associated small-scale fisheries make to food security and income generation and highlight the need to acknowledge the social-ecological importance of seagrasses in the seascape (Paper I). A discrepancy between low societal gains of the fishing of sea urchin predator fish species and their crucial importance in the food web (in controlling sea urchin populations and the associated grazing pressure on seagrasses) was identified (Paper II). These results suggest catch-and-release practice of sea urchin predator fish species, which could contribute to more balanced predator – sea urchin – seagrass food webs in the long run. The use of illegal dragnets was identified as a major threat to local seagrass meadows (Paper IV). Institutional elements influencing the use of such destructive dragnet were identified to be normative, cultural-cognitive and economic, which constitutes an institutional misfit to the current emphasis on regulative elements in a hierarchical manner (Paper III). Concerning future co-management initiatives, gear restrictions and education were the favoured management measures among all fishers (Paper IV). A majority of fishers were willing to participate in monitoring and controls, and most fishers thought they themselves and their communities would benefit most from seagrass-specific management. These findings highlight the need for actions on multiple scales, being the local-, management-, policy- and governance levels. The suggested actions include: education and exchange of ecological and scientific knowledge, gear management including the cessation of dragnet fishing, strengthening of local institutions, an active participation of fishers in enforcement of existing rules and regulations and an introduction of adequate alternative livelihood options.

Place, publisher, year, edition, pages
Stockholm: Department of Ecology, Environment and Plant Sciences, Stockholm University , 2017. , 69 p.
Keyword [en]
small-scale fisheries, co-management, social-ecological systems, ecosystem services, institutions, transformation, seagrass meadows, destructive gear, food-web interactions
National Category
Ecology
Research subject
Marine Ecotoxicology
Identifiers
URN: urn:nbn:se:su:diva-141052ISBN: 978-91-7649-762-3 (print)ISBN: 978-91-7649-763-0 (electronic)OAI: oai:DiVA.org:su-141052DiVA: diva2:1085468
Public defence
2017-05-05, Vivi Täckholmsalen, NPQ-huset, Svante Arrhenius väg 20, Stockholm, 09:00 (English)
Opponent
Supervisors
Note

At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 1: Manuscript. Paper 4: Manuscript.

Available from: 2017-04-10 Created: 2017-03-29 Last updated: 2017-04-03Bibliographically approved
List of papers
1. Food security and ecosystem service generation of seagrass-associated small-scale fisheries: the case of southwest Madagascar
Open this publication in new window or tab >>Food security and ecosystem service generation of seagrass-associated small-scale fisheries: the case of southwest Madagascar
(English)Manuscript (preprint) (Other academic)
Abstract [en]

Small-scale fisheries play globally a crucial role for food security and poverty alleviation. This is particularly true in developing countries, where people often are to a high extent depending on the resources their surrounding ecosystems have to offer. Many small-scale fisheries around the world are however under pressure, and in the need of better management. A seascape approach including all habitats has been emphasized for marine small-scale fisheries. This study is based on interviews with fishers and investigates the importance of seagrass beds for small-scale fishery households and their food security of in southwestern Madagascar. The three specific aims of this study were to: i) analyze if seagrass-associated fish contributes to subsistence and/or economy of local fishing households, ii) identify and compare seagrass ecosystem goods and services valued by local people in a rural and an urban setting and iii) analyze links between local people and seagrasses in terms of local ecological knowledge, use and traditions. The results show that seagrasses are the most important fishing habitats for most fishers, seagrass-associated fish species are both the most important and most commonly fished species, and seagrass derived fish and invertebrates are highly important daily sources of animal protein. The highest valued seagrass ecosystem goods and services are the provision of fishing grounds and the provision of food and income for the communities in general. These findings illustrate that seagrasses contribute both through subsistence and income generation to food security and wellbeing of coastal people in southwestern Madagascar. Therefore, there is a need to consider seagrass ecosystems in management of small-scale fisheries, to build more resilient small-scale fisheries which can sustain food security for future generations.

Keyword
seascape management, seagrass, provision of fish, ecosystem services, subsistence, income
National Category
Biological Sciences
Research subject
Marine Ecotoxicology
Identifiers
urn:nbn:se:su:diva-141045 (URN)
Available from: 2017-03-29 Created: 2017-03-29 Last updated: 2017-03-31Bibliographically approved
2. Cascade effects and sea-urchin overgrazing: An analysis of drivers behind the exploitation of sea-urchin predators for management improvement
Open this publication in new window or tab >>Cascade effects and sea-urchin overgrazing: An analysis of drivers behind the exploitation of sea-urchin predators for management improvement
Show others...
2015 (English)In: Ocean and Coastal Management, ISSN 0964-5691, E-ISSN 1873-524X, Vol. 107, 16-27 p.Article in journal (Refereed) Published
Abstract [en]

Marine ecosystems generate a wide variety of goods and services, but are globally deteriorating due to multiple drivers associated with anthropogenic activities. Intense fishing pressure can lead to changes in structure and function of marine food webs. Particularly overfishing of predatory species at high trophic levels can cause cascading effects leading to ecosystem degradation, affecting both marine organisms and people dependent on them. In the Western Indian Ocean region, intensive fishing takes place and degradation of coral reefs and seagrass beds has been documented. One reason behind this degradation is overgrazing by increasing numbers of sea urchins. An essential step towards better management is to thoroughly understand the drivers leading to such changes in ecosystems. Against this background, the general aim of this study was to gain understanding about whether sea urchin predators in the WIO region are fished, and to identify the drivers behind the fishing of these species. The study had four objectives: (i) to document if and how predatory fish eating sea urchins are caught in smallscale fisheries, (ii) to assess if, and if so why, sea urchin predators are targeted species, (iii) to assess if and to what degree local ecological knowledge (LEK) on ecological complexity involving sea urchins and their predators (e.g. trophic cascades) is present among local fishers, and (iv) to identify fishers' suggestions for management that can reduce problems linked to sea urchin overgrazing. The results show that all investigated species of sea urchin predators are fished by local small-scale fishers. Most sea urchin predators are not actively targeted, are not popular local food fish, and have minor use and economic importance for fishers. This stands in sharp contrast to their ecological keystone role by controlling sea urchin populations. The fishers' awareness and LEK were weak and partly lacking. Management suggestions targeted mostly the symptoms of food web changes rather than the drivers behind them.

Based on the results we suggest that management of degraded ecosystems, as a result of food web changes, should encompass a wide variety of strategies and scales. Specific suggestions for sea urchin predator management are education of local stakeholders on destructive gear effects and food web complexity, further investigations of catch- and release fishing as well as the use of selective gears.

Keyword
food web changes, fisheries management, overgrazing, small-scale fisheries, social-ecological drivers, LEK, trophic cascades, Kenya, Zanzibar
National Category
Biological Sciences
Research subject
Marine Ecotoxicology
Identifiers
urn:nbn:se:su:diva-141046 (URN)10.1016/j.ocecoaman.2015.01.010 (DOI)
Available from: 2017-03-29 Created: 2017-03-29 Last updated: 2017-03-31Bibliographically approved
3. Destructive gear use in a tropical fishery: Institutional factors influencing the willingness-and capacity to change
Open this publication in new window or tab >>Destructive gear use in a tropical fishery: Institutional factors influencing the willingness-and capacity to change
Show others...
2016 (English)In: Marine Policy, ISSN 0308-597X, E-ISSN 1872-9460, Vol. 72, 199-210 p.Article in journal (Refereed) Published
Abstract [en]

The aim of this study was to empirically assess institutional aspects shaping fishers' behavior leading to unsustainable resource use, by using the example of destructive drag-net fishing in Zanzibar, Tanzania. A broad institutional approach was used to specifically assess institutional factors influencing the fishers' reasons for the current use of destructive drag-nets as well as their willingness- and economic capacity to change to less destructive gears. Different regulative, normative, cultural-cognitive and economic factors (tradition, group-belonging, social acceptance, common practice, identity of drag-net users and weak economic capacity) were identified as critical elements influencing the current use of destructive gears, as well as obstructing changes to other gears. Hence, the importance of addressing all of these factors, matching to the different contexts, rather than focusing on fast-moving regulative measures, is emphasized to increase chances of management success. More promising approaches would be resource allocations to more sustainable fishing gears, well-managed gear exchange programs, as well as alterations of slow-moving normative and cultural factors, e.g. awareness raising on the advantages of more sustainable fishing gears, their traditional and cultural values, information on the actual income they generate, as well as education and an exchange of traditional knowledge on how to use them.

Keyword
Destructive fishing gear, Institutions, Small-scale fisheries, Gear exchange, Fisheries management
National Category
Earth and Related Environmental Sciences Agricultural Science, Forestry and Fisheries
Research subject
Marine Ecotoxicology
Identifiers
urn:nbn:se:su:diva-135237 (URN)10.1016/j.marpol.2016.07.001 (DOI)000383821500021 ()
Available from: 2016-11-10 Created: 2016-11-01 Last updated: 2017-03-29Bibliographically approved
4. Early steps for successful management in small-scale fisheries: An analysis of fishers', managers' and scientists' opinions preceding implementation
Open this publication in new window or tab >>Early steps for successful management in small-scale fisheries: An analysis of fishers', managers' and scientists' opinions preceding implementation
(English)Manuscript (preprint) (Other academic)
Abstract [en]

The chances of fisheries management to achieve positive outcomes increase when fishers and managers agree on the need for management, share preferences for certain management strategies and cooperate on their implementation. This study analyzes fishers’, managers’ and scientists’ opinions on different management measures for seagrass-associated small-scale fisheries in Zanzibar, Tanzania. Areas of agreements as well as disagreements were analyzed to identify common ground and facilitate the initiation of management processes towards more sustainable fisheries. The findings show that most fishers and managers agreed on the need to include seagrasses specifically in future management. There was further agreement on dragnets being the most destructive gears, as well as the use of dragnets being a major threat to local seagrass ecosystems. Gear restrictions excluding illegal dragnets were the favored management measure among all fishers (with fewer dragnet fishers supporting them compared to trap fishers); a result predicted by half of the managers, while the majority of managers advocated the use of temporary closures. Differences between fishers and managers were found concerning seaweed farming, eutrophication and erosion being potential threats to seagrass meadows. Finally, a majority of all fishers were willing to participate in monitoring and controls, and most fishers thought that they themselves and their communities would benefit the most from establishing seagrass management. The results of this study show that co-managed gear restrictions and the inclusion of different key actos in the management process including enforcement are promising starting points for the implementation of management for more sustainable small-scale seagrass fisheries in Zanzibar. 

Keyword
heterogeneity, small-scale fisheries, co-management, environmental governance, seagrass meadows, social-ecological, seascape, gear restrictions
National Category
Biological Sciences
Research subject
Marine Ecotoxicology
Identifiers
urn:nbn:se:su:diva-141048 (URN)
Available from: 2017-03-29 Created: 2017-03-29 Last updated: 2017-03-31Bibliographically approved

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