A comparative analysis between recreational and artisanal fisheries in a Mediterranean coastal area

The biological impact and the social characteristics of different artisanal (professional) and recreational fishing techniques on the marine resources of a coastal Mediterranean area were compared. Data were from artisanal and recreational surveys carried out between 2006 and 2010. Competition between recreational (particularly spear fishing) and artisanal fishers for the natural resources is important as 52% of the 98 species surveyed were caught by both types of fishers. A total of 87 species were caught by all artisanal fishing gears together (of which 84% were retained and 16% discarded). Recreational fishing caught 58 species of which none was systematically discarded. The two fishing techniques that raise major environmental concerns are spear fishing (very selective in terms of species and/or sizes and high intrinsic vulnerability of catches) and trammel netting (highest number of species discarded and highest number of species endangered). Important challenges from the social standpoint were found that need to be taken into account in the management of coastal fisheries in the Mediterranean Sea including: progressive disappearance of the artisanal fisheries, ageing of the artisanal fisher populations and decline in the number of fishing gears used by artisanal fishers.     

Biological implications of recreational shore angling and harvest in a marine reserve: the case of Cape Creus

• 1. Recreational shore fishing along the coast of the marine reserve of Cap de Creus (NW Mediterranean) was studied in 2007 and 2009 based on roving creel surveys (on‐site angler surveys during which anglers' harvests are examined by the survey clerk). The study aimed to assess the biological impacts of this leisure activity on coastal fish stocks and the potential risks arising from the use of exotic baits.
• 2. Recreational shore fishers employ seven different fishing techniques, of which the bottom fishing rod (a fishing rod whose hooks, together with the bait, lie on the bottom or near it by means of a heavy weight) is by far the most widely used method (nearly 90% of observations). In total, 25 fish species were identified in the catch from the bottom fishing rod.
• 3. The estimated annual shore fishing catches (c.3 tons) are much lower than those obtained by recreational boat and spear fishing (c.20 tons each), and those from commercial (artisanal) fishing (c.50 tons). The weighted mean vulnerability index and trophic level values in the catch from the bottom fishing rod are 52.2 and 4.03, respectively.
• 4. A minimum of 43% of the baits used by the shore anglers were live, non‐native species (mostly polychaetes).
• 5. Overall, results highlight the impact of shore angling on coastal fish communities of a protected area and the increasing environmental risks arising from the use of exotic marine baits, which constitute a potential and unregulated vector of introduction of non‐native species in the Mediterranean. Copyright © 2011 John Wiley & Sons, Ltd.

     

Biological and socioeconomic implications of recreational boat fishing for the management of fishery resources in the marine reserve of Cap de Creus (NW Mediterranean)

A survey of coastal recreational boat fishing was conducted in summer 2006 in the marine reserve of Cap de Creus (NW Mediterranean) to assess the biological and socioeconomic implications of this leisure activity. Recreational boat fishers employ four different fishing techniques: bottom fishing rod, fluixa, trolling and surface fishing rod. Although the targeted species depend on the fishing method used, a total of 33 fish species were identified in the catch (8 were pelagic or benthopelagic and the rest were demersal). Fishing effort was high since fishers fished an average of 4 h/day, 8 days/month and nearly 6 months/year. Apart from the highly varied exploitation of the fauna, recreational fishing in Cap de Creus has a large economic effect on the local economy since the majority of fishers were visitors who were spending holidays in one of the villages belonging to the Park, where most of expenditures related to angling activities were made. Overall, results highlight the pressure that recreational boat fishing exerts on fish communities, particularly on littoral, demersal ones. Considering these biological and socioeconomic implications, the competition between recreational and artisanal fishers for littoral resources and the low level of compliance with the current sport fishing regulations, the implementation of a comprehensive management strategy in Mediterranean costal areas is needed.     

Changes in a coral reef fishery along a gradient of fishing pressure in an Indonesian marine protected area

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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.     

A socio-economic perspective on gear-based management in an artisanal fishery in south-west Madagascar

Abstract  Artisanal fisheries are important socially, nutritionally and economically. Poverty is common in communities dependent on such fisheries, making sustainable management difficult. Poverty based on material style of life (MSL) was assessed, livelihoods surveyed and the relationship between these factors and fishery data collected using a fish landing study were examined. Species richness, diversity, size and mean trophic level of catches were determined for six fishing gears in an artisanal fishery in south-west Madagascar. There was little livelihood diversification and respondents were highly dependent on the fishery. No relationship was found between poverty and gear use. This suggests that poverty does not have a major impact on the nature of the fishery; however, this study was dominated by poor households, so it remains possible that communities with more variation in wealth might show differences in fishing methods according to this parameter. The fishery was heavily exploited with a predominance of small fish in the catches. Beach seines caught some of the smallest fish, overlapped in selectivity with gill nets and also had the highest catch per fishers. Thus, a reduction in the number of beach seines could help reduce the catch of small fish and the overlap in selectivity among gears.     

Direct interaction between wild fish aggregations at fish farms and fisheries activity at fishing grounds: a case study with Boops boops

Coastal aquaculture installations concentrate large numbers of wild fish species of both ecological and economic importance, including schools of bogue, Boops boops (L.), in high abundance and biomass. The aggregated species consume large quantities of the easily available pellets lost from cages. As a consequence, the physical condition of farm‐associated wild fish is increased and their physiology is altered. These changes may influence local fisheries as many of these aggregating species are targeted by fishers. We assess whether local fishers catch wild fish that have previously aggregated at fish farms by comparing the body condition, trophic indexes, diet overlap and the fatty acid (FA) composition of B. boops obtained from local fish markets and around fish farms. Bogue captured by trammel‐nets and around fish farms facilities presented a similar biological condition, as well as high quantities of pellets in the gut, and their FA profile was affected by vegetal‐derived FAs. In contrast, bogue captured by trawlers were not influenced by fish farms, as they consumed natural trophic resources. We conclude that artisanal fishers exploit these aggregated fish populations once they have dispersed away from farms, and benefit from a ‘biomass export’ from fish farms at a local scale.     

Understanding fishing‐induced extinctions in the Amazon

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Relationships between catch and effort in Fijian multispecies reef fisheries subject to different levels of exploitation

Abstract The catch-per-unit-effort (CPUE) and value-of-catch-per-unit-effort (VPUE) of reef-associated fish species from six Fijian native fishing grounds ( qoliqoli ) subject to different fishing intensities were determined using records of fishing activity from a voluntary logbook scheme. Line and spear fishing techniques were used for more than half the total fishing time (h person^-1 d^-1) in all qoliqoli , and yet the favoured technique in a given qoliqoli was frequently less efficient (lower CPUE) than other techniques. The popularity of relatively ineffective fishing methods implies that fishermen did not always attempt to maximize their catch rates. To compare fishing effort in different qoliqoli , all effort was rescaled on the basis of its recorded efficiency (measured as multispecies CPUE) and expressed as hours equivalent to boat-based spear fishing over coral by day to catch fish for sale. Total fishing intensity in the six qoliqoli ranged from 72 to 4310 h km^-2 reef year^-1. The relationship between catch and effort was linear at all fishing intensities, suggesting that the qoliqoli were all fished on a sustainable basis. Furthermore, whilst there was a significant difference in CPUE and VPUE between the one or two qoliqoli with lowest fishing intensity and all the others, there were no significant differences between these other qoliqoli in terms of the VPUE of the saleable multispecies boat catch or the CPUE of species from piscivorous and carnivorous genera ( Epinephelus, Lethrinus and Plectropomus ) which the fishermen prefer to catch.     

Fisheries catches and the carrying capacity of marine ecosystems in southern Brazil

The carrying capacity of marine shelf ecosystems in southern Brazil for harvestable species is analyzed by (1) quantifying the amount of available primary production appropriated by fisheries catches, (2) evaluating the trend in the mean trophic level of fisheries, and (3) simulating the ecosystem effects of “fishing down the food web” in an intensively exploited shelf region. Fisheries utilize ca. 27 and 53% of total primary production in the southern and south-eastern shelf regions, respectively. Regional variation in the carrying capacity appropriated by fisheries results from differences in the primary production, catch volume and trophic transfer efficiencies. Overall, fisheries landings do not display a trend of decreasing trophic level with time due to the collapse of the sardine fishery and the recent increasing of offshore fishing for higher trophic level species, mainly tunas and sharks. However, the simulations show that fishing down the food web through fisheries that target small pelagic planktivorous fishes, while at first increasing catches in intensively exploited regions, has the potential of decreasing yields, by interrupting major energy pathways to exploited, high-trophic level species. The consequences of these results to the design of precautionary measures for future fishing policies are discussed.     

Interactions between fisheries and cetaceans in the Thracian sea (Greece) and management proposals

Greek fisheries (purse seine, trawling and small‐scale coastal, by order of importance) mostly operate in the Thracian Sea, which despite its relatively small size relative to the Aegean Sea (≈4.4%) is the most productive region in Greek waters due to its elevated nutrient concentration. The Thracian Sea is also vital to several species of cetaceans, mainly bottlenose dolphin, Tursiops truncatus (Montagu), and common dolphin, Delphinus delphis L. The area has been proposed as a potential cetacean conservation hotspot. For this reason, the interactions between fishing activities and local cetacean populations have been investigated through reports of stranded dolphins, interviews with fishers, surveys and detailed dolphin stomach content analysis. Reports of stranded cetaceans and interviews with fishers revealed cases of cetacean entanglement in fishing nets, as well as frequent dolphin damage to fishing nets. Necropsy stomach analysis of stranded dolphins revealed a preference for fish and cephalopods of low commercial value, indicating a low trophic overlap between cetaceans and commercial fisheries. Recommendations for the management of fisheries–cetacean interactions in the Thracian Sea are provided.     

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.     

Complexity of applying minimum legal sizes (MLS) of retention in an indigenous coral reef fishery

Abstract Retaining coral reef fish for subsistence during commercial fishing is a common practice for indigenous fishers in the Torres Strait, Australia, despite being inconsistent with legislation. Fisher access point surveys were completed between 2004 and 2006 on three islands in Torres Strait to characterise this subsistence practice and assess the level to which it undermines current minimum legal fish sizes. Approximately 15% of the annual total catch was retained for subsistence during commercial fishing. Notably, subsistence catch of the most commercially valuable species almost entirely comprised individuals smaller than the minimum legal sizes. The higher proportions of undersized individuals of valuable species retained during commercial fishing on some of the islands were most likely associated with an increase in professionalism of the fishers. These results demonstrate how the intended outcomes from a management strategy can be undermined when the specific operational conditions of the fishery are not considered. Successful implementation of management arrangements in indigenous communities ultimately depends on the sociocultural conditions of the communities and their understanding and adherence to the rules. A productive way forward for the management of this fishery is greater engagement of indigenous communities and managers in co‐management arrangements.     

The nexus of fun and nutrition: Recreational fishing is also about food

Recreational fishing is a popular activity in aquatic ecosystems around the globe using a variety of gears including rod and line and to a lesser extent handlines, spears, bow and arrow, traps and nets. Similar to the propensity to engage in voluntary catch‐and‐release, the propensity to harvest fishes strongly varies among cultures, locations, species and fisheries. There is a misconception that because recreational fishing happens during non‐work (i.e. leisure) time, the nutritional motivation is negligible; therefore, the role of recreational fishing in supporting nutrition (and thus food security) at regional, national or global scales is underappreciated. We consider the factors that influence whether fish will be harvested or released by examining the motives that underlie recreational fishing. Next, we provide an overview of the magnitude and role of recreational fishing harvest in supporting nutrition using regional case‐studies. Then, we address issues such as contaminants and parasites that constrain the ability of fish harvested by recreational fishers to be consumed. Although recreational fishing is foremost a leisure activity, the harvest of fish for personal consumption by recreational fishers has contributed and will continue to contribute to human nutrition by providing an accessible, affordable and generally highly sustainable food source, notwithstanding concerns about food safety and possibly overfishing. Attempts to better quantify the role of fish harvested by recreational fishers and the relative contribution to overall food security and personal nutrition will provide resource managers and policymakers the information needed to guide management activities and policy development.     

Temporal dynamic and economic valuation of recreational fisheries of the lower Cuiabá River,Brazilian Pantanal

Fisheries are the most common ecosystem service that fish provide to human populations, yet recreational fisheries are often overlooked when evaluating such services. Here, the socioeconomic profiles of fishers, the composition of their catches and catch per unit effort (CPUE) are described, to estimate the economic value of the recreational fishery on a stretch of the Cuiabá River in the Brazilian Pantanal. Questionnaires were used to obtain socioeconomic information and fishing yield from fishers for 2013 and 2014. Additionally, a census on the number of fishers and fishing platforms along the sampled region was conducted in 2018. This recreational fishery mostly involves middle class adult males, based mostly in the Cuiabá city metropolitan region. They invested, on average, US$41.1 (SD = US$16.5, median = $35.2) per fishing visit, catching around 19 fish species. Overall, mean CPUE from the recreational fishery was 42.20 fish/fisher.day (17.4 kg/fisher/day). Annual economic value of this recreational fishery was estimated at around US$1.8 million, which highlights the importance of this activity to the local economy. Greater environmental conservation efforts are recommend to ensure the long-term viability of this ecosystem service.     

舟山渔场禁渔线以外海域单拖网鱼类群落结构变动分析

根据2010年2月、5月、9月和11月对舟山渔场禁渔线以外海域渔业资源底拖网调查数据,对该海域鱼类群落结构的季节变化进行了分析。调查中共捕获鱼类80种,隶属于13目,49科,59属,其中以鲈形目最多（30种）。Simpson多样性指数（C）、Shannon-Wiener多样性指数（H＇）和Pielou均匀度指数（J＇）均呈现出9月以后逐渐升高、随后下降、5月基本达到最低点的趋势,而Margalef丰富度指数（D）在5月较高,表明5月鱼类种类丰富度较高。资源生物量曲线（ABC）的结果受优势种影响较大,2月质量优势度曲线位于数量优势度曲线之上;5月质量优势度曲线与数量优势度曲线相交;9月和11月数量优势度曲线位于质量优势度曲线之上。营养级-平均体质量关系曲线斜率的绝对值5月最小,9月最大,表明经过伏季休渔以后,9月鱼类平均体质量有所增加,特别是高营养级鱼类,而经过持续捕捞以后,至5月鱼类平均体质量整体降到较低水平。     

渔获物平均营养级在渔业可持续性评价中的应用研究进展

高强度的捕捞努力量和渔业管理不力等因素导致全球范围内传统渔业资源的衰退,近年来渔获物平均营养级(MTL,mean trophic level)作为以生态系统为基础的渔业管理评价指标被普遍应用。本文在广泛收集国内外相关文献资料基础上,系统地介绍了MTL在渔业资源评价中的研究进展。已有研究显示,MTL能够利用已知渔获数据来分析,且参数化较为简便,在评价渔业可持续性中优势明显。受以渔获量作为生态系统指标、营养级(TL,trophic level)随体长的变化、渔获统计数据质量、低TL种类的过多捕捞和海域环境富营养化等因素的影响,在评估渔业资源利用状况时,需将MTL与剔除TL小于3.25物种下的3.25MTL、渔业均衡指数(FIB)等营养指标综合分析。此外,综合运用多指标,将营养指标与渔获组成、中上层鱼类与底层鱼类产量的比值、市场价格等指标结合分析,有助于掌握引起MTL变动的因素,更加全面地掌握捕捞活动下鱼类群落结构的实际变化状况。     

Trap mesh selectivity and the management of reef fishes

The regulation of mesh size has frequently been proposed as a management measure for fish traps, the predominant gear used by the reef fish fisheries in the Caribbean. Studies on trap mesh selectivity show that mesh size is a determinant of catch rates and the size at which fish recruit to fish traps. Mesh size also affects the species composition in fish traps, probably through size selectivity. Other factors also affect catch rates, and the fish size and species composition in traps, for example, soak time, trap design, trap size, species body shape. Given the variety of growth rates and maturity schedules of reef fish commonly taken in fish traps in the Caribbean, no single mesh size will optimise the yield or protect against recruitment overfishing for the entire range of exploited species. Preliminary data suggest that the fishing power of traps may decrease with increased mesh size. This would reduce the effective fishing effort and thus mortality on fully recruited size classes. Studies indicate that the mesh sizes currently in use in most Caribbean countries are too small, and that a minimum mesh size of at least 3.8–5.1 cm would be required to optimise yields for local consumption. Comparative fishing experiments indicate that an increase in mesh size in areas of high fishing mortality typically results in a reduction in catch per trap. Thus increasing trap mesh size can be expected to result in short‐term loss in revenue for fishers. However, no studies have examined the times that would be required for catches to return to the levels prevailing before the increase of mesh size, and thereafter, for fishers to recover the losses incurred during the transition period. To provide managers with an estimate of the impacts that mesh‐size regulation could have on fishers, the recovery time of catches and the financial recovery times for fishers should be modelled for a hypothetical assemblage of 10–15 reef fishes using available information. These studies would enable managers to plan for the implementation of mesh‐size increases and to communicate the potential benefits to fishers in quantitative terms.     

Marine recreational fishing and the implications of climate change

Marine recreational fishing is popular globally and benefits coastal economies and people's well‐being. For some species, it represents a large component of fish landings. Climate change is anticipated to affect recreational fishing in many ways, creating opportunities and challenges. Rising temperatures or changes in storms and waves are expected to impact the availability of fish to recreational fishers, through changes in recruitment, growth and survival. Shifts in distribution are also expected, affecting the location that target species can be caught. Climate change also threatens the safety of fishing. Opportunities may be reduced owing to rougher conditions, and costs may be incurred if gear is lost or damaged in bad weather. However, not all effects are expected to be negative. Where weather conditions change favourably, participation rates could increase, and desirable species may become available in new areas. Drawing on examples from the UK and Australia, we synthesize existing knowledge to develop a conceptual model of climate‐driven factors that could impact marine recreational fisheries, in terms of operations, participation and motivation. We uncover the complex pathways of drivers that underpin the recreational sector. Climate changes may have global implications on the behaviour of recreational fishers and on catches and local economies.     

Management challenges of small-scale fishing communities in a protected reef system of Veracruz, Gulf of Mexico

Abstract  Socioeconomic characterisation of fishing activities in the Veracruz Reef System National Park was used to develop a management system which balances the community's livelihood, and the conservation needs of the protected area. A survey was applied to four sectors of the fishing community: the fishers, fishers' wives, retailers and local population. The survey determined their perceptions about: (1) fishing as a lifestyle; (2) economic alternatives; (3) perspectives about the future; (4) environment; and (5) knowledge of the National Park as a protected area. Fishers devoted an average of 27 years fishing, investing an average of 12 h per day giving a regular income of 15–20 US$. Most interviewed (60%) were full-time fishers, with fishing the only family income source. Fishers are predominately educated to primary school level (64%).The main problem faced by fishers and the communities were economic opportunities but 89% believed that mariculture could be an alternative income source. There was strong ecological awareness, with 75% aware of the decline in fisheries resource and 62% knowing about the role of protected areas. There was divided opinion about future perspectives. Inefficient organisation and communication between authorities and fishers were identified as obstacles to co-management. Discussion on alternative incomes and a proposal involve fishers in co-management initiatives are presented.