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.     

Filling a blank on the map: 60 years of fisheries in Equatorial Guinea

Despite a scarcity of pertinent information, it has been possible to reconstruct time series of marine fisheries catches for Equatorial Guinea from 1950 to 2010 using per capita fish consumption and population numbers for small‐scale fisheries, catch rates and number of vessels for industrial fisheries and discard rates to estimate the discarded bycatch. Small‐scale fisheries, industrial large‐scale fisheries, domestic and legal and illegal foreign fisheries and their discards are all included. Total catches were estimated at 2.7 million tonnes over the time period considered, of which 653 000 t were caught domestically compared to 187 000 t reported by FAO. This shows that fisheries have more importance for Equatorial Guinea's food security than the official data suggest. In contrast to what is suggested by official figures, fisheries were shown to be strongly impacted by civil and political unrest; notably, they declined overall because of civil and political conflicts, socio‐demographic dynamics, and a growing role of the newly discovered oil resources, which directly and indirectly threaten the food security of the people of Equatorial Guinea.     

Trends,current understanding and future research priorities for artisanal coral reef fisheries research

Artisanal coral reef fisheries provide food and employment to hundreds of millions of people in developing countries, making their sustainability a high priority. However, many of these fisheries are degraded and not yielding their maximum socioeconomic returns. We present a literature review that evaluates foci and trends in research effort on coral reef fisheries. We describe the types of data and categories of management recommendations presented in the 464 peer‐reviewed articles returned. Identified trends include a decline in articles reporting time‐series data, fish catch biomass and catch‐per‐unit effort, and an increase in articles containing bycatch and stakeholder interview data. Management implications were discussed in 80% of articles, with increasing frequency over time, but only 22% of articles made management recommendations based on the research presented in the article, as opposed to more general recommendations. Key future research priorities, which we deem underrepresented in the literature at present, are: (i) effectiveness of management approaches, (ii) ecological thresholds, trade‐offs and sustainable levels of extraction, (iii) effects of climate change, (iv) food security, (v) the role of aquaculture, (vi) access to and control of fishery resources, (vii) relationships between economic development and fishery exploitation, (viii) alternative livelihoods and (ix) integration of ecological and socioeconomic research.     

Artisanal fisheries in urban reservoirs: a case study from Brazil (Billings Reservoir, São Paulo Metropolitan Region)

Billings Reservoir is an urban reservoir located in the São Paulo Metropolitan Region. It supports 101 active artisanal fishermen. To describe this fishery, landings were recorded daily between February 1996 and January 1997 at Colônia (23° 50' 57' S; 46° 40' 02' W). In every landing, a data collector recorded catch, effort, fishing gears and fishing grounds. A total of 147 593 kg of fish were recorded in 3515 fishing trips. The exotic Nile tilapia, Oreochromis niloticus (L.), was the main species exploited (81.4% of the annual catches). Five other species were also targeted: the characid Astyanax eigenmaniorum (Cope) (13.0% of the annual catches); the erythrinid Hoplias aff . malabaricus (Block) (2.1%); the exotic cyprinid Cyprinus carpio L. (Campos & Fernández-Yépez) (2.4%); the curimatid Cyphocharax modestus L. (1.1%); and the pimelodid Rhamdia sp. (0.1%). Two main groups of fishermen were discriminated using Principal Components Analysis; these were associated with the type of fishing gear and fishing strategies, i.e. those who exploited Nile tilapia with cast nets and beating gill nets, and those who exploited other species with set gill nets. Management and maintenance of this fishery should consider the positive top-down effects that Nile tilapia could have in controlling eutrophication and also the social benefits.     

Comparative analysis of artisanal and recreational fisheries for Dentex dentex in a Marine Protected Area

The common dentex, Dentex dentex (L.), is an iconic marine coastal fish in the Mediterranean Sea. This study was performed in the Bonifacio Strait Natural Reserve (BSNR), (NW Mediterranean Sea). The aims were to: (1) evaluate temporal variation of the artisanal fishing of common dentex (2000–2012); (2) compare and quantify catch rates, fishing techniques and catch composition for artisanal and recreational fisheries, and determine the influence of management measures by both activities; and (3) estimate the production of both artisanal and recreational fisheries. Fishery data were collected from different artisanal fishing surveys (onboard fishing vessels and landings) and recreational fishing surveys (roving). The gears with the highest rates of exploitation were longline (3554 g per 100 hooks) and Trolling (351 g boat^?1 h^?1 ±SE), respectively, for artisanal and recreational fishing. This study showed that catches by both activities were quantitatively higher in partially protected areas than outside them. Production estimations suggest that the recreational fishery contributes significantly to fishing mortality and that it can magnify the negative effects of artisanal fisheries. Specific measures are needed for the sustainable fishery management of common dentex.     

Global significance of seagrass fishery activity

Seagrass meadows support fisheries through provision of nursery areas and trophic subsidies to adjacent habitats. As shallow coastal habitats, they also provide key fishing grounds; however, the nature and extent of such exploitation are poorly understood. These productive meadows are being degraded globally at rapid rates. For degradation to cease, there needs to be better appreciation for the value of these habitats in supporting global fisheries. Here, we provide the first global scale study demonstrating the extent, importance and nature of fisheries exploitation of seagrass meadows. Due to a paucity of available data, the study used a global expert survey to demonstrate the widespread significance of seagrass‐based fishing activity. Our study finds that seagrass‐based fisheries are globally important and present virtually wherever seagrass exists, supporting subsistence, commercial and recreational activity. A wide range of fishing methods and gear is used reflecting the spatial distribution patterns of seagrass meadows, and their depth ranges from intertidal (accessible by foot) to relatively deep water (where commercial trawls can operate). Seagrass meadows are multispecies fishing grounds targeted by fishers for any fish or invertebrate species that can be eaten, sold or used as bait. In the coastal communities of developing countries, the importance of the nearshore seagrass fishery for livelihoods and well‐being is irrefutable. In developed countries, the seagrass fishery is often recreational and/or more target species specific. Regardless of location, this study is the first to highlight collectively the indiscriminate nature and global scale of seagrass fisheries and the diversity of exploitative methods employed to extract seagrass‐associated resources. Evidence presented emphasizes the need for targeted management to support continued viability of seagrass meadows as a global ecosystem service provider.     

Global marine fisheries discards: A synthesis of reconstructed data

As part of the global marine fisheries catch reconstruction project conducted by the Sea Around Us over the last decade, estimates were derived for discards in all major fisheries in the world. The reconstruction process derives conservative but non‐zero time‐series estimates for every fisheries component known to exist, and relies on a wide variety of data and information sources and on conservative assumptions to ensure comprehensive and complete time‐series coverage. Globally, estimated discards increased from under 5 million t/year (t = 1,000 kg) in the early 1950s to a peak of 18.8 million t in 1989, and gradually declined thereafter to levels of the late 1950s of less than 10 million t/year. Thus, estimated discards represented between 10% and 20% of total reconstructed catches (reported landings + unreported landings + unreported discards) per year up to the year 2000, after which estimated discards accounted for slightly less than 10% of total annual catches. Most discards were generated by industrial (i.e. large‐scale) fisheries. Discarding occurred predominantly in northern Atlantic waters in the earlier decades (1950s–1980s), after which discarding off the West Coast of Africa dominated. More recently, fleets operating in Northwest Pacific and Western Central Pacific waters generated the most discards. In most areas, discards consist essentially of marketable taxa, suggesting a combination of poor fishing practices and poor management procedures is largely responsible for the waste discarding represents. This is important in an era of increasing food security and human nutritional health concerns, especially in developing countries.     

Drivers of the upper River Amazon giant catfish fishery

Artisanal fishers of the upper reaches of the Amazon River use a variety of tactics to catch giant Brachyplatystoma catfish species: Brachyplatystoma vaillantii Valenciennes, Brachyplatystoma rouseauxii (Castelnau) and Brachyplatystoma filamentosum (Lichtenstein). These catfish are migratory, caught with different gears, by different communities, and influenced by temporal and spatial changes in river conditions. Facing these factors, it was hypothesised that the catfish fishery yields in the headwaters of the Amazon are determined by fishing tactics efficiency, riverscape features and governance basis. Data on catfish yields were collected from two contrasting riverscapes (rapids and floodplains) in the most important Amazonian affluent in Colombia—the Caquetá River. Results indicated that: (1) catfish yield was strongly associated with fishing effort in both riverscapes, (2) seasonal drivers play an essential influence in the high rapids reach, and river level in the low floodplain reach, (3) community strategies affected yield, although the effect is different depending on the gear used as the environment profile affects enforcement. Based on the results, it was concluded that efficient upstream management of these species should combine specific measures for each riverscape with an integrated approach to the river production system that considers catfishes longitudinal migrations and the growth overfishing occurring in the Amazon estuary.     

Historical perspective of artisanal encircling gillnet use at the Brazilian coast: Changes in fishing behaviour is mirrored by dwindling stocks

Managing coastal resources sometimes requires looking into the past, as this provides a baseline against which present conditions may be gauged. The present study evaluated the circumstances that led Brazilian coastal fishers to modify their use of encircling gillnets. Other stressors (i.e. water pollution and habitat degradation) acted synergistically on the fisheries dynamic between 1950 and 2016. Declining catches of several species were observed through fishers' historical perception and through fisheries landing records. Three notable trends in net handling were associated with distinct historical periods. Specifically, pressures from modern fishery practices and gear (e.g. monofilament nets), the adoption of spiral setting arrangements and the increasing use of trammel nets appear responsible for the decline of many stocks. Mullet, seabass, jack and pilchard stocks decreased over time and were associated the changes witnessed in the encircling net operations. These changes occurred in response to overexploitation of fish stocks, to exploit the dwindling fisheries resources. The study also discusses the reasons leading fishers to accept how encircling gillnets ought to be used, their interpretation of such changes and the implications these changes have for fisheries management.     

Community-based management of subsistence fisheries in Samoa

Much subsistence fishing in tropical regions is based in discrete communities which have a high level of marine awareness and some degree of control of adjacent waters. These factors provide an ideal basis on which to motivate communities to manage their own marine resources. A fisheries extension programme in Samoa encouraged each village community to define its key problems, discuss causes, propose solutions and take appropriate actions. Various village groups, including women's and untitled men's groups, provided information which was recorded (as problem/solution trees) on portable white-boards. The extension process culminated in a community-owned Fisheries Management Plan which listed the resource management and conservation undertakings of the community. Undertakings ranged from enforcing laws banning destructive fishing methods to protecting critical marine habitats. Within the first 2 years, the extension process commenced in 65 villages, of which 44 have produced Village Fisheries Management Plans to date. A large number (38) of these villages chose to establish community-owned Marine Protected Areas.     

China's distant‐water fisheries in the 21st century

We conservatively estimate the distant‐water fleet catch of the People's Republic of China for 2000–2011, using a newly assembled database of reported occurrence of Chinese fishing vessels in various parts of the world and information on the annual catch by vessel type. Given the unreliability of official statistics, uncertainty of results was estimated through a regionally stratified Monte Carlo approach, which documents the presence and number of Chinese vessels in Exclusive Economic Zones and then multiplies these by the expected annual catch per vessel. We find that China, which over‐reports its domestic catch, substantially under‐reports the catch of its distant‐water fleets. This catch, estimated at 4.6 million t year^?1 (95% central distribution, 3.4–6.1 million t year^?1) from 2000 to 2011 (compared with an average of 368 000 t·year^?1 reported by China to FAO), corresponds to an ex‐vessel landed value of 8.93 billion € year^?1 (95% central distribution, 6.3–12.3 billion). Chinese distant‐water fleets extract the largest catch in African waters (3.1 million t year^?1, 95% central distribution, 2.0–4.4 million t), followed by Asia (1.0 million t year^?1, 0.56–1.5 million t), Oceania (198 000 t year^?1, 144 000–262 000 t), Central and South America (182 000 t year^?1, 94 000–299 000 t) and Antarctica (48 000 t year^?1, 8 000–129 000 t). The uncertainty of these estimates is relatively high, but several sources of inaccuracy could not be fully resolved given the constraints inherent in the underlying data and method, which also prevented us from distinguishing between legal and illegal catch.     

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.     

Fishing operations and adaptive strategies of small‐scale fishers: insights for fisheries management in data‐poor situations

Small‐scale fisheries' management is complex given its multigear, multispecies nature; despite this, fishing effort has usually been controlled by nominal units, ignoring changes in effective fishing effort. This study aimed to understand the adaptive strategies of small‐scale fishers in San Felipe, Yucatan, Mexico through an analysis of their fishing operations. Minor changes in trip numbers among three seasons were observed, but increases in fishing time, depth and travel costs from one season to another at the operational level were found. It was also evident that high value species at the beginning of the season were gradually replaced by low‐value finfish as the season progresses. The results provide insights for new adaptive management strategies according to fisher's adaptive responses. For instance, using boats or fishing trips as fishing effort units in Yucatan may not be the most appropriated unit for management, as fishers adapt their strategies at different levels.     

Contemporary and emerging fisheries in The Bahamas—Conservation and management challenges,achievements and future directions

The harvest of marine resources has long‐standing cultural and economic importance to The Bahamas and other small island developing states. Tourists and residents place a demand on local marine resources, particularly Caribbean spiny lobster, Panulirus argus (Latreille), queen conch, Lobatus gigas (Linnaeus) and Nassau grouper, Epinephelus striatus (Bloch), and many fishery products are also sold on the global market. Illegal, unreported and unregulated fishing coupled with inadequate regulations and enforcement are the main factors contributing to the decline of Bahamian fisheries along with other anthropogenic impacts. This article reviews the status of fisheries management in The Bahamas using economically and ecologically important species as case studies to highlight conservation successes, knowledge gaps and deficiencies in existing management approaches. The review concludes with an examination of how emerging fisheries and improved conservation management strategies have the potential to improve economic and food security throughout the archipelago.     

When is a fisher (not) a fisher? Factors that influence the decision to report fishing as an occupation in rural Cambodia

In the developing world, the majority of people who fish in inland areas do so primarily for subsistence needs. This suggests that survey or census questionnaires which collect information concerning the occupations of respondents will underreport the number of people who fish, and corollary to this, misrepresent dependence on fishing as a support service for food and supplemental income. This study uses the results of a household survey conducted in 37 villages across Cambodia to quantify the amount of fishing that is done by inland fishers who do not report fishing as a primary or secondary occupation. The study also identifies the household characteristics which influence the decision of an individual who fishes to report fishing as an occupation. Fifty‐eight percent of households whose members engaged in fishing activities did not report fishing as an occupation. Individuals whose household owned farmland, earned off‐farm income and fished primarily for subsistence needs were significantly less likely to report fishing as an occupation. When assessing the importance of fishing to inland rural communities for the purposes of rural planning and policy development, relying solely on census‐style occupation or employment data will misrepresent the contributions of subsistence fishing to household welfare.     

Tracking interactions: Shifting baseline and fisheries networks in the largest Southwestern Atlantic reef system

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Assessment of a fisheries legal framework for potential development of an ecosystem approach to fisheries management in large rivers

Most small‐scale fisheries of large floodplain rivers are still managed under conventional top‐down regulations that limit the application of an ecosystem approach to fisheries (EAF) due to inappropriate legal frameworks. Using the Parana–Paraguay River fisheries (Argentina) as an example, this study examines the extent to which existing provincial legislations can be prepared for the adoption of an EAF. An Ecosystem Fishing Legal Approach (EFLA) framework is proposed based on different criteria across an environmental–ecological, fishing, social, economic and institutional template. Policy Component Scores (PCS) and an Integrated Policy Legal Index (IPLI) were applied to assess the degree of compliance by current provincial legislations to EAF implementation. Cluster analysis was used to recognise the potential for articulating a legal framework at a basin scale. The EFLA framework, which provided an accurate picture of how provinces were poorly prepared to adopt an EAF for the Paraguay–Parana fisheries, and represents a suitable tool that can be adapted and extended to other basins around the world.     

Perceptions of resource users and managers towards fisheries management options in Kenyan coral reefs

Abstract  The perceptions of Kenyan resource users and managers towards gear and area management were examined through face-to-face interviews to identify areas of agreement and disagreement and compare with compliance. Opinions were sought about gears that sustained fish catch, gears discouraged by the government and traditional leaders, and the benefits of area management were sought. There was good agreement among most groups and traditional leaders about the gears discouraged by government, with beach seines and spear guns the most commonly listed. This indicates good agreement between government and traditions, promoted by recent government legislation, but compliance was poor since nearly two-thirds of fishers used these recently prohibited gears. This was due, in part, to lesser agreement concerning gears that promote a sustainable fishery, with spear guns and beach seines scaled low, but moderately supported in this respect by those fishers that use these gears. These gears persist because of the lack of shared evidence about the yields and sustainability of the various gears and social and economic aspects, such as increased competitiveness and decreased costs of the gears. There is evidence that beach seines lower yields but this gear persists because it is more competitive and has lower costs to the user than the other gears. Spear guns also persist because young and poor fishermen, who cannot afford costs associated with other gears, use them. Government employees scaled the benefits of area, and particularly closed area, management, higher than fishers, which is an issue of conflict but, nonetheless, has good compliance because of the long history of closed area management. For both types of management, shared perceptions alone were insufficient to achieve high compliance, and active enabling and enforcement by managers is needed.     

Assessing the influence of gilthead sea bream escapees in landings of Mediterranean fisheries through a scale‐based methodology

Gilthead sea bream (Sparus aurata L.) aquaculture has rapidly spread around the Mediterranean Sea. Fish escapes from sea cages are one of the major problems for the industry and also represent a threat to the marine environment. Fishery catches are also influenced by escape events, being mirrored in increased landings of cultured species. However, within the Mediterranean, studies shedding light on the incidence of escaped individuals in fisheries landings are scarce. Firstly, the present study describes a simple scale‐examination methodology to distinguish escaped from wild S. aurata landed by coastal fisheries. Secondarily, the incidence of escapees is assessed within landings of the species in the western Mediterranean. The scale readings revealed a monthly incidence of escapees between 11.2 and 20.8%, representing 6.8% of the total income derived from these landings. Moreover, morphological differences between wild fish captured near and far from fish farms point towards escape events as a source of potential genetic admixture between cultured and wild genotypes. Socio‐economic and ecological implications of escapees are discussed, and a set of management guidelines proposed, to prevent and/or mitigate the negative influences of escaped fish on the ecosystem and traditional users of the coast such as fisheries.