The behavioural dynamics of fishers: management implications

In pursuing their livelihood, fishers develop strategies when faced with changes in regulations and other fishery conditions. Changes involve each individual in a decision‐making process governed by his/her own goals or constraints. Despite this reality, the complex dynamics of fishing has usually been ignored in designing management initiatives, which has contributed to management failures in many parts of the world. Fishers have generally been treated as fixed elements, with no consideration of individual attitudes based on their operating scales (geographical, ecological, social and economic) and personal goals. We review existing research on the social, economic and behavioural dynamics of fishing to provide insight into fisher behaviour and its implications for fisheries management. Emphasis is placed on fisher perception, and how fishers develop dynamic fishing tactics and strategies as an adaptive response to changes in resource abundance, environmental conditions and market or regulatory constraints. We conclude that knowledge of these dynamics is essential for effective management, and we discuss how such information can be collected, analysed and integrated into fisheries assessment and management. Particular emphasis is placed on small‐scale fisheries, but some examples from industrial fleets are provided to highlight similar issues in different types of fisheries.     

Dynamics of fishing gear allocation by fishers in small-scale coastal fisheries of Pelabuhanratu Bay, Indonesia

Abstract  Fishing gear usage in small-scale coastal fisheries of Pelabuhanratu Bay, Indonesia was explained by two approaches: temporal fishing gear allocation analysis and adaptive responses of fishers to external factors, especially climate and abundance of target species. Gear usage, with the exception of hand lines and seine nets, was more intensive during the dry season than the rainy season. The decision to use seine nets was governed by seasonal variability in the abundance of Auxis thazard , Lacepède, and Trichiurus spp. to the catch. Sustainable management of fishing activities in Pelabuhanratu Bay requires proportional reductions in the use of lift nets and fixed gillnets across the seasons rather than gear specific effort reductions.     

Quantifying fishing effort: a synthesis of current methods and their applications

The need to accurately quantify fishing effort has increased in recent years as fisheries have expanded around the world and many fish stocks and non‐target species are threatened with collapse. Quantification methods vary greatly among fisheries, and to date there has not been a comprehensive review of these methods. Here we review existing approaches to quantify fishing effort in small‐scale, recreational, industrial, and illegal, unreported and unregulated (IUU) fisheries. We present the strengths and limitations of existing methods, identifying the most robust methods and the critical knowledge gaps that must be addressed to improve our ability to quantify and map fishing effort. Although identifying the ‘best’ method ultimately depends on the intended application of the data, in general, quantification methods that are based on information on gear use and spatial distribution offer the best approaches to representing fishing effort on a broad scale. Integrating fisher’s knowledge and involving fishers in data collection and management decisions may be the most effective way to improve data quality and accessibility.     

Trade‐offs in triple‐bottom‐line outcomes when recovering fisheries

Almost all environmental management comes at an economic cost that may not be borne equitably by all stakeholders. Here, we investigate how heterogeneity in catch and profits among fishers influences the trade‐off among the triple‐bottom‐line objectives of recovering a fish population, maximizing its economic value and distributing restrictions equitably across fishers. As a case‐study, we examine management reform of an ecologically and economically important coral reef fishery operating within the Great Barrier Reef Marine Park. Using a simulation model, we find that total profitability of the fishing industry is 40% lower if recovery plans are equitable when compared to the most economically efficient plan. However, efficient recovery plans were typically highly inequitable because they required some fishers to cease fishing. Equity was defined according to different norms, and the efficiency loss was greatest when catch losses were shared equally across fishers rather than in proportion to their historical catch. We then varied key social, economic and biological parameters to identify cases when equity and efficient recovery would trade‐off most strongly. Recovery plans could be both efficient and equitable when heterogeneity in fisher's catches and individual catch efficiencies was lower. If fishers were homogenous then equitable plans could have maximal economic efficiency. These results emphasize the importance of considering heterogeneity in individual fishers when designing recovery plans. Recovery plans that are inequitable may often fail to gain stakeholder support, so in fisheries with high heterogeneity we should temper our expectations for marked increases in profits.     

Factors influencing fish catch levels on Kenya's coral reefs

Abstract  The factors influencing fish catches on Kenya's coral reefs were studied. Catch data were collected at the species level by counting the number of fish landed at each landing site of each fishing ground. Live coral cover, topographic complexity, fish and sea urchin density, and the number of fishers and gear units used in each fishing ground were compared with catch data. Fishing grounds included one location where only basket traps were allowed, six locations where all gear types were used except beach seines, and three locations where all types of gear, including beach seines, were used. Catch and effort variables were similar across the fishing grounds whereas live coral cover and sea urchin density differed ( P  < 0.01). The sites fished by all types of gear including beach seines had the lowest coral cover (8.4 ± 0.9%) and topographic complexity (1.12 ± 0.01). Catch levels were positively correlated with the number of fishers and fish density but not with the number of gear units deployed or sea urchin density. The number of fishers and live coral cover were the strongest factors determining total catch levels. The results suggest that high levels of fishing effort coupled with the use of destructive gear types, exacerbate the effects of overfishing on Kenya's reefs.     

Narco‐Fish: Global fisheries and drug trafficking

This study analyses drug trafficking associated with fisheries around the globe. Records of vessel interdiction carried out between 2010 and 2017 suggest that the global trade of illicit drugs relies increasingly on fishing vessels. Fishery‐based trafficking is growing. A key obstacle to understanding the scope of this problem is the limited data on activities that are intentionally obscured, such as drug trafficking. Using a Fermi estimation technique for determining unknown values from limited data, we analyse 292 known cases of fishing boats engaged in drug shipment between 2010 and 2017. Results suggest that drug shipment sizes per vessel are becoming smaller over time, even as the total flow of drugs is increasing. Counter‐drug enforcement intensifies this effect, suggesting that drug trafficking networks adapt to interdiction efforts making use of smaller vessels to lower the risk of seizure. The use of fishing vessels in drug trans‐shipment has tripled over the past 8 years to about 15% of the global retail value of illicit drugs. Small‐scale fishers are at risk of turning to drug trade as an economic buffer against poverty, especially in contexts of mounting competition over declining fish stocks or strict marine conservation. At the same time, illicit capital flowing from the narcotics trade into fisheries may be driving over‐capitalization of fisheries and unsustainable resource use, ultimately to the detriment of resource‐dependent coastal communities and marine ecosystems. Future research is needed to better understand whether and how small‐scale fishermen turn to drug trade to counter livelihood risks of various kinds.     

Digital camera monitoring of recreational fishing effort: Applications and challenges

The growing awareness of the impact that recreational fishers can have on fish stocks has highlighted the paucity of information used to inform their management. Most of the available information on the scale and nature of recreational catch and effort has come from intermittent and labour‐intensive surveys that provide fragmented insights into often highly variable fisheries. Digital cameras offer a more cost‐effective means of continuously monitoring trends in recreational fishing effort, and it is surprising that greater use of this approach has not been made to date given its widespread use in other contexts. We share lessons learnt from four early adopter studies in New Zealand, Australia and Germany, where digital cameras have been used to monitor recreational fishing effort. Many of the challenges that we have encountered and overcome were initially unforeseen, and we suggest solutions and strategies to address these issues. We conclude that all aspects of a camera‐based monitoring system should be considered from the outset, to optimize the utility and value of the information they provide over the long term. Aspects to consider include the location and configuration of a camera system, ensuring service continuity, image quality, data storage, image interpretation and ultimately the analysis of any data collected. Robustly designed digital camera monitoring systems can be used to gain greater insight into recreational fishery dynamics, leading to more informed, responsive and effective fisheries management.     

Understanding fishing‐induced extinctions in the Amazon

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Implications of recreational fishing for elasmobranch conservation in the Great Barrier Reef Marine Park

• 1. 309 Great Barrier Reef Marine Park recreational fishers were surveyed to examine recreational catch and harvest of elasmobranchs and to explore recreational fishers' handling behaviour and attitudes.
• 2. Elasmobranchs represented 6% of fishers' total catch of all fish (including released individuals), and 0.8% of fishers' total harvest (i.e. retained individuals) across all survey days. The majority of elasmobranchs caught by fishers were released, primarily because they were perceived as being inedible.
• 3. Recreational fishers' self‐reported handling and release behaviour for elasmobranchs is largely consistent with ‘best practice’ guidelines except that fishers had low use of circle hooks and barbless hooks, and a significant proportion (33%) reported using stainless steel hooks.
• 4. Most fishers had positive attitudes towards elasmobranchs, placing high importance on releasing sharks and rays in good condition (86%), high value on their existence (84%), and low value on catching them (63%).
• 5. Results indicate that post‐release mortality is probably the largest source of recreational fishing mortality of elasmobranchs in the Great Barrier Reef. Future research should be targeted at obtaining better estimates of species‐specific post‐release mortality levels, understanding how post‐release survival can be increased by changing fishing techniques or fisher behaviour, and developing more effective methods of engaging fishers in elasmobranch conservation. Copyright © 2009 John Wiley & Sons, Ltd.

     

Fishers' experiences and perceptions of marine mammals in the South China Sea: Insights for improving community‐based conservation

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An interview‐based approach assessing interactions between seals and small‐scale fisheries informs the conservation strategy of the endangered Mediterranean monk seal

1. Small‐scale fisheries may pose a serious threat to the conservation of marine mammals. At the same time various factors have led to the decline of small‐scale fisheries, often making them unsustainable. Current rates of biodiversity loss and the reduction of fish stocks and fisheries dictate a thorough understanding of fisheries‐related issues and the implementation of effective management actions.
2. The Mediterranean monk seal is one of the most endangered marine mammals on Earth; its survival in the eastern Mediterranean Sea is threatened by negative interactions with fisheries. A nationwide questionnaire survey among fishers and port police authorities was carried out in Greece to describe the main characteristics of small‐scale fisheries, and to understand the nature and assess the magnitude of negative interactions between the monk seal and these fisheries. Questionnaire information was verified by a second round of interviews during landings.
3. The main attributes of the fishers, their fishing boats, and their practices were characteristic of the small‐scale fisheries sector. Overfishing was considered the main reason for fish‐stock reduction, and negative interactions with marine mammals was considered the main issue for the fishing sector.
4. Monk seals were present, caused damage, and got accidentally entangled in fishing gear throughout Greece. Damage to fishing gear was recorded mainly during spring and summer, and on average affected 21% of all fishing trips and 1% of nets deployed during a fishing trip.
5. Based on these results, the implementation of general and specific nationwide fishery management and conservation actions are proposed. These actions are mainly aimed at improving fish stock status, changing the behaviour of the fishers, and mitigating seal–fishery interactions in Greece, while promoting the recovery of the Mediterranean monk seal in the eastern Mediterranean Sea.

     

Effectiveness of shore‐based remote camera monitoring for quantifying recreational fisher compliance in marine conservation areas

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Long‐term changes in fishery resources of an estuary in southwestern Atlantic according to local ecological knowledge

Long‐term changes in the abundance of fisheries resources from the Patos Lagoon estuary and adjacent coastal waters in southern Brazil have been observed. Despite this understanding, it is well known that the perception of pristine state of the environment is susceptible to inter‐generational changes, commonly known as shifting baseline syndrome (SBS). An useful approach in the reconstruction of pristine scenarios and in lack of data, as often occurs in small‐scale fisheries, is the local ecological knowledge (LEK). Temporal changes in the perception of 81 fishers with 1–63 years of fishing about the resources status were analysed. More experienced fishers reported larger catches, heavier individuals and perceived a greater number of species as "scarce" nowadays and "common" at the beginning of their careers proving the existence of a SBS among them. Over time, the number of fishing sites with very high catches decreased and fishing sites shifted from the lower towards the upper estuary. The perception of the fishers corroborated the real decreasing scenario in estuarine fisheries resources shared with industrial fishing in coastal waters. The results reinforce the utility of LEK for reconstruction of biological scenarios when no empirically obtained data are available.     

Thirty years of change and the future of Alaskan fisheries: Shifts in fishing participation and diversification in response to environmental,regulatory and economic pressures

Heterogeneity in human responses and decision‐making can contribute to the resilience of social–ecological systems in the face of environmental, political and economic pressures. In fishery systems worldwide, the ability of harvesters to maintain a diverse portfolio of fishing strategies is important for building adaptive capacity. We used a case‐study approach to examine the complexity of factors that inhibit or promote diversification in fisheries of Alaska, one of the major fishing regions of the world. Through a combination of harvest records and literature review, we explored shifts in participation and portfolio diversity in Alaskan fisheries over three decades. The four case‐studies examined the responses of fishers, fleets and communities to multiple, intersecting pressures, including biological declines, market and price dynamics, fishery privatization and the 1989 Exxon Valdez oil spill. These cases illustrate how stressors acting at multiple scales can encourage or constrain opportunities for diversification, and that these opportunities may be spread inequitably across participants. Overall, we found evidence for reduced participation and increasing specialization in Alaskan commercial fisheries. While numerous factors explain these trends, policies like individual quota systems and the increasing cost of entry into fisheries are forcing consolidation at local to regional scales. A portfolio approach to managing fisheries that reduces barriers to diversification and includes broad representation of resource users and communities in management may help to maintain opportunity and choice for fishers.     

Contribution of marine fisheries to worldwide employment

Marine fisheries contribute to the global economy, from the catching of fish through to the provision of support services for the fishing industry. General lack of data and uncertainty about the level of employment in marine fisheries can lead to underestimation of fishing effort and hence over‐exploited fisheries, or result in inaccurate projections of economic and societal costs and benefits. To address this gap, a database of marine fisheries employment for 144 coastal nations was compiled. Gaps in employment data that emerged were filled using a Monte Carlo approach to estimate the number of direct and indirect fisheries jobs. We focused on estimating jobs in the small‐scale fishing sector. We characterized small‐scale fishing as (i) primarily geared towards household consumption or sale at the local level; (ii) conducted at a low level of economic activity; (iii) minimally mechanized; (iv) conducted within inshore areas; (v) minimally managed; and/or (vi) undertaken for cultural or ceremonial purposes. In total, we estimated that 260 ± 6 million people are involved in global marine fisheries, encompassing full‐time and part‐time jobs in the direct and indirect sectors, with 22 ± 0.45 million of those being small‐scale fishers. This is equivalent to 203 ± 34 million full‐time equivalent jobs. Study results can be used to improve management decision making and highlight the need to improve monitoring and reporting of the number of people employed in marine fisheries globally.     

秘鲁沿岸秘鲁鳀渔场及渔汛分析

秘鲁鳀(Engraulis ringens)是栖息于东南太平洋沿岸的小型中上层鱼类,了解秘鲁鳀渔场和渔汛的状况有助于渔情预报工作的开展进而实现资源的合理利用。利用2005~2014年秘鲁各港口的上岸量数据,以上岸量(landings)、总捕捞努力量(fishing effort)和单位捕捞努力量渔获量(CPUE)为指标分析秘鲁鳀渔场分布及渔汛;结合二因素方差分析(two-factor analysis of variance)探究渔场月份和纬度上的显著性差异;利用分位数的方法,找出各年的旺汛时间。研究表明,每年的4~6月和11~12月为秘鲁鳀的主汛期;主要的捕捞区域分布在7°S~13°S;渔汛的前中期,上岸量和捕捞努力量有着明显的年间差异,而CPUE在渔汛后期年间差异明显。方差分析表明,不同月份和不同纬度对捕捞努力量[ln(effort+1)]有极显著的影响(P0.01);5月为一年中最主要的捕捞阶段。旺汛期分析表明,第一渔汛阶段的旺汛一般在5月出现,而第二渔汛阶段的旺汛一般在11月出现。研究结果有助于对秘鲁沿岸秘鲁鳀渔场及渔汛的认识。     

Illustrating the critical role of human dimensions research for understanding and managing recreational fisheries within a social‐ecological system framework

Effective management of recreational fishing requires understanding fishers and their actions. These actions constitute critical links between social and ecological systems that result in outcomes that feedback and influence recreational fishers' actions and the management of these actions. Although much research exists on recreational fishers and their actions, this research is often disconnected from management issues. One way to help to overcome this disconnect is to illustrate how past research on the social component of recreational fishing fits within an emerging coupled social‐ecological system (SES) framework. Herein, a conceptual SES is first developed with specific attention to recreational fisheries. This SES is then used to illustrate the importance of considering human dimensions research for articulating, studying and ultimately managing key outcomes of recreational fisheries (e.g. fish population conservation, fisher well‐being) using the example of harvest regulations and a brief review of past interdisciplinary research on recreational fishing. The article ends by identifying key research needs including understanding: how factors such as management rules affect the diversity of actions by recreational fishers; how governance and management approaches adapt to changing social and resource conditions; and how recreational fishers learn and share information.     

Identifying potential causes of fish declines through local ecological knowledge of fishers in the Ganga River,eastern Bihar,India

Local ecological knowledge (LEK) can offer insights into fisheries management by describing long‐term changes that are difficult to unravel in data‐poor river‐floodplain fisheries. LEK is derived from complex interactions between fishers’ observations of environmental change and their institutional capacities to manage fisheries. Hence, it is important to understand where and how LEK and formal scientific studies on fish species’ decline could complement each other. In this paper, the causes of decline of 58 fish and two shrimp taxa were identified from LEK data (1999–2019) obtained from river–floodplain fisheries of the Gangetic plains (Bihar, India). Qualitative analyses of LEK were used to generate species‐specific hypotheses and historical insights on their declines. Destructive fishing, overfishing and the Farakka barrage were cited by fishers as the major causes of declines. Potential reasons for these perceptions were explored in relation to fishers’ experiences of conflicts in the region over fishing rights and access.     

Fishermen's perception on the sustainability of small‐scale fisheries and dolphin–fisheries interactions in two increasingly fragile coastal ecosystems in western Greece

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